Log Entries

Project Location: Australia

Entry Date Summary Description
Entry Date Summary Description
2009-12-02 First part Made my first part today, Jeepee!
SNX-F08-11, a simple piece, the aft attach angle required on the flap detend angle, made out of 1x1x.125 angle.

Edit 24/12/2009: Had to make this part again, I noticed I cut off part of the wrong leg and therefore made a mirrored version of this part.
Oh well first part, first mistake, sure it won't be the last.
2009-12-03 More fuselage angle parts Finished SNX-F10-06, hook mount, goes on to the seat belt attach assembly.
Cut some other 1x1x.125 angle to required lengths, SNX-F14-7L, SNX-F14-2L, SNX-F13-6R.
2009-12-04 Cutting 1x1x.125 angle Decided to change strategy and first cut all the angle to their required lengths with a compound mitre saw.
Finished most of the 1x1x.125 angle today, only two more 10ft pieces to cut.
2009-12-05 Cutting 1x1x.125 angle Finished cutting all the 1x1x.125 angle to the required lengths.
2009-12-06 Cutting angle Cut all of the 2.5x2.5x.1875 and 2x2x.1875 to required lengths
2009-12-08 Wing attachment blocks Cut the 4 wing attachment blocks, W11-03 out of a 12x1x1.25 aluminum bar. As expected my rather cheap compound mitre saw struggles a bit cutting thick piece of aluminum and the cuts end up a bit rough, therefore I cut the pieces just a little long so I have some margin to clean up the ends pieces afterwards.
2009-12-11 Cutting 1.5x.1.5x.125 angle Cut all the 1.5x.15x.125 angle to the required lengths
2009-12-13 Cutting 2x.2x.125 angle Cut almost all of the 2x2x.125 angle to the required lengths today, only a few more pieces remaining.
2009-12-14 CAD drawing Did not feel like cutting angle today so I decided to play with AutoCAD, re-drawing SNX-F08-08 placing 3 flap positions instead of 2.
2009-12-16 finished cutting the 2x2x.125 angle Finished cutting the 2x2x.125 angle to the required lengthsas well, and with that, I've finished cutting to length all the angle I have for now.
The only angle I'm still missing is the 2.5x2.5x.125 angle since my supplier does not stock this, I'll try to find it elsewhere and start shaping parts in the mean time.
2009-12-17 CAD drawing Did some more design work on my modified version of the flap detent angle, F08-08.
After checking with other builders on the Yahoo Sonex groups if my 3-flap position modification was ok, numerous builders pointed out that it's a good idea to also put "safety nibs" on each position to prevent the flap handle from coming out of the selected position, regardless of whether you stick with the std 0-10-30 configuration or a 0-10-20-30 configuration.
So here's my design with "safety nibs".

I also drew the pivot angles for the idler assembly in AutoCAD, F10-18R/L, the next piece I will work on.
The reason I make these CAD drawings beforehand is that I plan to print, these, cut them out and spray glue them on the angle to define my cut lines and drill positions, rather than draw them directly on the angle (the spray glue easily comes off with warm water afterwards).
I only plan to do this for the more complex shapes, for those I think this technique is easier and a more accurate, off course for the simple pieces this is a bit of an overkill.
2009-12-20 F10-18 Shaped, deburred and pilot drilled the idler pivot angles, F10-18R/L.
2009-12-20 F08-08 Shaped and deburred the flap detent angle, F08-08, this was the most difficult piece so far. This is also the first time I don't stick to the plans, like many others have done, I've put 3 flap positions instead of 2.
2009-12-22 CAD drawing Did some more CAD drawing today, F14-11 and F08-10, cut them out and spray glued them on the angle.
2009-12-24 finished F08-10 and remade F08-11 Finished F08-10, and when opening the F08 drawing I noticed that I cut the wrong leg off F08-11 (my very first part) so I had to make that one again.
2009-12-25 F14-11L/R Made F14-11L/R, the left and righthand gear attach angles.
2009-12-27 Various wing angles Finished W11-09 (2x), the vertical stiffener angle; W11-10L/R, tie down fittings left and righthand; and W11-11 (2x), outboard stiffener angles.
2009-12-28 F22-06, F03-05L/R and F03-06L/R Worked for 4.5 hours today and was able to finish 5 more fuselage parts: F22-06, F03-05L, F03-05R, F03-06L and F03-06R.
F03-06L/R were the first angle parts I made that required to reform the angle itself, in this case from 90 to 86 degrees. There are several methods to do this, I chose the mallet & vice method.
2009-12-29 L05-07 Finished the brake handle pivot angle, L05-07. As usual I first drew the part in AutoCAD, printed and spray glued it to the angle, and then cut it out. I find I draw quicker in AutoCAD the straight on the piece.
2009-12-29 W11-08 Made the first of the 2 wing upper stiffener angles, W11-08. I also drew the end attachment angles, W11-05, in AutoCAD, and printed them, ready to be and spray glued to the angle and cut.
2009-12-30 W11-08/2 and W11-05 Finished the second of the two wing upper stiffener angles, W11-08. Also completed both wing end attachment angles, W11-05.
2009-12-31 F10-19, F14-12L and F14-12R Finished 3 more parts today, made out of 2x2x.125 angle this time.
F10-19 attach angle and F14-12L/R left and right hand seat belt attach angles.
The seat belt attach angles were more difficult then they look.
2010-01-02 F15-04L/R Parts are getting more and more difficult. Made only two parts in 3.5 hours today, F15-04L/R, the left and right hand rudder pedal mount angles.
2010-01-03 CAD drawing Did some more CAD dawing today, F22-05, F23-03 and F23-04.
These last two parts need the angle opened to 95 degrees. I had a first go at this using just my bench vice. Bad idea, broke the vice axle. It is still partly usable but will now open no further then 4cm, I will have to buy a better vice.
2010-01-04 F23-03 and F23-04, opening angle Had a second go trying to open the angle of the parts F23-03 and F23-04.
I don't have a new vice yet but I am still able to use the old one to clamp just 1 leg of the angles. After doing some research on the Sonex yahoo groups, this, in combination with a crowbar, is all I need (for now).
I clamped the angle with one leg in the vice and squeezed the crowbar between the angle and the vice, then it just requires a little force pushing the crow bar up until the desired angle is reached, worked perfectly.
After this procedure the legs of the angle are not perfectly straigt anymore but slightly concave. This is normal and acceptable since the angle can and will not bend on the thickest part of the material, but you can get rid of this almost completely by removing material from the apex of the angle on the
outside. It's purely a cosmetic finishing touch but never the less, this is what I did. Again I have thank the people on the Sonex yahoo groups for sharing this little trick.
2010-01-05 F22-05 Finished F22-05, the aft shear web aft attach angle. First piece I had to cut a half circle out of the angle, not easy but I took my time so all went ok.
2010-01-06 continued F23-03 and F23-04 Continued working on the two pieces that cost me a bench vice trying to open the angle to 95 degrees. I have not finished these pieces yet but I am close, only a little bit of final finishing remains.
I also installed a new bench vice today, a much stronger (and more expensive) one, I tried opening / closing some scrap pieces of angle and this went like nothing using this vice. Lesson learned: cheaper tools will eventually cost you more in the end (I already had learned this lesson before but it seems I need to be reminded every so often).
2010-01-07 finally finished F23-03 and F23-04 Today I finally finished the two parts that triggered a lot of swearing on my behalf and cost me a bench vice, F23-03 and F23-04.
However, the result is quite nice I would say, removing some material from the apex of the angle with the belt sander and scotch-brite wheel really makes the 95 degree angle look perfect, you can’t see any concave bits on the legs and the amount of material removed is not noticeable either.
Those Sonex yahoo groups really are a valuable source of information.
2010-01-08 T03-03 (2) Finished both T03-03 tail main spar attach angles.
These angles had to be closed to 80 degrees, no problem with my new vice.
2010-01-16 T12-05 After a week away on a business trip it took a little time to get back in to it. Finished one part today, T12-05
2010-01-17 W13-02L/R Made the left and right hand root rib attach angles today. These angles have to be adjusted before trimming, the left hand angle has to be opened to 93.9 degrees, the right hand angle has to be closed to 86.1 degrees. No problems adjusting the angles this time, all went very smooth.
2010-01-18 W20-02 and W20-03 Started working on the main root wing attach angles, W20-02 and W20-03. 2 are required of each so 4 parts in total.
I drew the templates in AutoCAD today, printed and cut them.
The W20-02 angles need to be opened to 93.9 degrees and the W20-03 angles need to be closed to 86.1 degrees so I did this first before cutting.
I then spray glued the templates on and started cutting out the exact shape with the bandsaw.
That's all for now clocked about 2 hours today, I'll try to finish these angles tomorrow.
2010-01-19 continued W20-02 and W20-03 Continued on the main root rib attach angles W20-02 and W20-03. All 4 pieces are formed, cut to size, sanded and deburred, all that remains is drilling the 3/32" and 1/8" pilot holes.
2010-01-20 finished W20-02 and W20-03 Finished the 4 root rib attach angles today W20-02 and W20-03.
Drilling the holes took longer then expected, 1.5 hours today.
2010-01-23 W21-03, W21-04, W21-06 and W21-07 Made the 4 bellcranck pivot assembly angles today, W21-03, W21-04, W21-06 and W21-07. The parts are completely finished apart from the drilling for the pivot bushings, this can only be done when the assembly is put together with the spacer blocks in between.
2010-01-26 W11-07 and W11-03 Finished 2 more root attach angles, W11-07. Also shaped the 1 of the 4 wing attach blocks, W11-03 which go on the same root attach assembly.
2010-01-27 W11-03 continued Finished shaping the 3 remaining wing attach blocks, W11-03.
2010-01-28 F14-07 R and L Worked on F14-07R and 14-07L today, left and right hand rudder pedal angles.
I finished the right hand angle but the left hand angle has only been cut and drilled, it still needs final finishing.

These are the first of the longer angles to make. I started with all the shorter angles because if I make a mistake on those, I know I will still have enough raw angle to remake them and not have to order new pieces. Now that I have a bit of experience, I'll start making the longer ones.
2010-01-30 finished F14-07L Finished the left hand rudder pedal angle today 14-07L. It just needed some cleaning up on the scotch-brite wheel and pads. The right hand version was already finished yesterday.
2010-01-30 drawing F14-02L/R and F14-13L/R Drew F14-02R/L in AutoCAD, cut them out and spray glued them on the raw angles.
Also drew F14-13R/L on the angle, these are pretty straight forward, CAD paper templates required here.
2010-01-31 F14-02L/R and F14-13L/R Finished more fuselage angles today, F14-02L/R and F14-13L/R.
2010-02-01 started F14-08L/R Started working on F14-08L/R, drew the parts in CAD and spray glues them to the piece, also reshaped the angles to the required 86.1 degrees.
2010-02-02 continued F14-08L/R I was not quite happy with how the reshaping of the left hand angle to 86.1 degrees turned out so I've re-worked this one a bit. This proved to be more difficult then the initial closing of the angle, in the end it turned out fine though.
Also rough cut the left hand angle today.
2010-02-06 Finished F14-08L/R Finally finished the two fwd wing attach angles, F14-08L/R, I'm quite pleased with the result
2010-02-07 Nearly finished F14-09L/R Nearly completed the aft wing attach angles F14-09L/R today. I just need to drill a few holes to complete these parts.
These angles have to be opened to 93.9 degrees again which is a challenge with such long angles. After some research on the Sonex Yahoo groups I decided to use the "pipe" method, this worked well.
2010-02-08 Finished F14-09L/R Drilled the holes and did some final cleaning up of the aft wing attach angles F14-09L/R.
2010-02-11 Realy finished F14-09L/R and also finished F16-10 After looking at the drawing for F14-09L/R again, I notices I forgot to drill the holes on the wider side of the angle, so I did these first today.
I also completed F16-10, a fuselage lower forward cross tie.
2010-02-13 Finished F16-09 Finished F16-09 this morning, th fuselage upper forward cross tie.
2010-02-13 Started working on W11-01 (2) Drew the lower spar angles in AutoCAD, printed them and spray glued them on the pieces this afternoon.
I will cut the angles tomorrow.
These are quite complex shapes on 3/16 thick angle so this will realy test my bandsaw skills, looking forward to it.
2010-02-15 W11-01 continued Rough cut both W11-01 angles, the main spar lower stiffener angles, also filed deburred and final finished one of the two angles. These parts are critical structural angles so I have to take my time, make sure they are 100% perfect. I'll finish the second angle tomorrow.
2010-02-16 Finished W11-01 Finished the W11-01 angles, the main spar lower stiffener angles.
One of the two was already nearly completed yesterday, today I filed deburred and final finished the second of the two angles and gave both a final cleanup with the scotch-brite pads.

These angles are 3/16" thick, thicker then most of the angles I've been cutting so far which are 1/8" thick.
They are also quite complex in shape so they will have been good practice for when I start working on the 3/16" thick tail spar angles T03-02 and T06-03, pieces also known as the "spars from hell" in the Sonex builders community.
2010-02-17 Started working on F13-06L/R Started on the forward fuselage lower longerons F13-06L/R. I cut the pieces filed and deburred today. They just need to be pilot drilled and cleaned up a little now.
2010-02-18 Finished F13-06L/R Finished the forward fuselage lower longerons, F13-06L/R, today. Not very difficult pieces but the longest I've made so far.
2010-02-20 Started working on F13-03L/R Drew layout of F13-03L/R straight on the angles and marked all hole locations.
2010-02-21 Continued working on F13-03L/R Continued on F13-03L/R today, the forward fuselage upper longerons.
There are some tricky bits to these, an oval shaped hole for the canopy bow has to be made in both, and the left longeron requires 2 slots for the canopy hook angle.
So far so good, hopefully finish them tomorrow.
2010-02-23 Panel design #1 Probably way too early but I could not help myself from having a first go at designing the panel.

The main idea is keep it light,
MicroAir transponder & radio with Stratomaster Velocity instruments will do nicely in this case
2010-02-24 Still working on F13-03L/R Not much more to report, hopefully I can finish these parts tomorrow.
2010-02-27 Finished F13-03L/R Finally finished F13-03L/R. The canopy bow oval holes and the 2 slots for the canopy hook angles took more time and effort to make then expected.
2010-03-01 T03-02 Finally started on one of the 2 horizontal tail spar angles, T03-02.
These angles are also known by Sonex builders as the "spar angles from hell".
They will sure test my bandsaw skills.
For the moment I've only started drawing the layout on the rough cut angle.
2010-03-03 Continued working on T03-02 Did some more drawing work on T03-02 today
2010-03-04 Continued working on T03-02 Rought cut the AFT horizontal tail spar, T03-02.
As expected, this requires a bit of bandsaw skills, it went alright though.
Next filing, deburring and finishing.
2010-03-05 Continued working on T03-02 Started filing work on T03-02.
Every time I use that Vixen file, I must recognise it's power. It is the most powerfull tool in my arsenal.
2010-03-06 Finished T03-02 Finally finished T03-02 the first of the 2 "spar angles from hell".
In total this part took about 10 hours but it turned out great.
Always take your time, would be the key message here, think before making every cut.
2010-03-07 T06-03 Started working on the forward horizontal tail spar fitting, the second and most difficult of the 2 "spar angles from hell".
2010-03-10 Continued working on T06-03 Did a lot of filing work on T06-03 today, and still have more to do.
2010-03-11 Continued working on T06-03 Did more filing grinding and deburring work on T06-03 today.
Hopefully I can get it ready to do the 22 degree bends (with a 1/2 radius) this weekend, which is the most difficult part.
2010-03-13 More work on T06-03 Did another 4 hours work on the horizontal tail forward spar fitting angle.
The angle is now formed filed and deburred, which is necessary to prevent cracks when bending.
I drilled most pilot holes on the angle except from the ones which are close to the bend line and I also drilled the 13/16” holes at the end of the cut outs but did not do the cuts yet.
(I got this strategy from Eric Witherspoon’s site, it seemed logical)

I practiced the 22 degree bend with a ½” radius on some scrap metal as well.
Some people choose to make a special bending tool for this job, others seem equally successful using a much simpler method, I chose something in between.
The method I chose is squeezing the part between a piece of 1” steel pipe, and wooden V-block in my bench vice.
This method worked very well on the scrap pieces, let’s hope it works just as well on the real piece.
2010-03-14 Bending T06-03 Bending the horizontal tail forward spar fitting to the required 22 degrees went smoothly, no problems, just make sure everything is nicely lined up.
2010-03-14 Finished T06-03 After bending T06-03 all I had to do was cut out the legs to the holes which were already drilled before bending.
Off course filing, deburring and finishing took a bit of time on this piece as well.
2010-03-15 Discarding T06-03 After a closer inspection I’ve decided I will remake T06-03.
The 22 degree bends did not turn out perfect, to say the least.
It seems one of the bends is not completely straight and both are not a tight ½” radius.
I drew de bend around the steel pipe in AutoCAD and immediately it became clear what happened, once you start bending the actual angle gets in the way of the pipe and this it will move away from the theoretical brake line.
You can see this clearly on the image attached, when the piece is still straight, the steel pipe would be nicely positioned on the brake line and right against the angle, but once we introduce the bend, the pipe has to overlap with the angle in order to stay on the brake line as shown.
I should have thought this one through a bit more, 10+ hours of work down the drain...

For now I will continue making some other parts while I reconsider how I will do the bends.
2010-03-15 Drawing F08-09, L05-05 and C04-07 I am not keen to start straight away on a new T06-03 so I've decided to make some easier parts first, the control levers:
- F08-09 the elevator trim lever
- L05-05 the brake lever
- C04-07 the brake lever

These are made out of flat 1/8 and 3/16 material, I have not ordered my flat material yet but I have more then enough scrap from cutting legs off the angles that will do nicely for these parts.

Today I drew the templates for these three levers in CAD.
2010-03-16 L05-05 Cut filed and deburred L05-05, the brake lever.
I will do the optional finger grooves as well, I think it looks too much like a stick without them.
Later, I will also cover the handle with "grip dip" to give them a rubber coat.
2010-03-17 L05-05 Finished L05-05 today, the brake handle (with the optional finger grooves).
This is the first of the 3 control levers I started earlier this week to be finished.
2010-03-18 F08-09 and C04-07 Cut, filed, deburred and final finished the elevator trim lever and the flap handle, they only need a few bends to be finished now.
2010-03-19 Finished F08-09 and C04-07 Did the bends on F08-09 and C04-07 the flap handle and elevator trim lever.
2010-03-20 F26-02L/R and F26-03L/R Made the AFT fuselage right hand and left hand upper and lower longerons today. These parts are simple, they just need a little corner cut off the legs but because they are so long (almost 3m) they are difficult to work with. The angels had a few dents as well so took some cleaning up on the scotch-brite wheel.
2010-03-21 C02-03 Since I'm now completely finished with all the angle stock I initially bought and I'm still waiting for my 2.5x2.5x.125 angle to arrive, I'm continuing whatever scrap .125 and .1875 aluminium I cut from the angle pieces I've already made, to make some of the flat .125 and .1875 parts.
The pieces I made this morning were the 2 rudder cable adjusters, C02-03, easy straight forward pieces to make.
2010-03-21 F26-05L/R Made 2 more pieces from some left-over scrap 3/16 aluminium, cut from one of the angles. F26-05L/R, the AFT fuselage left hand and right hand upper vertical splice plates.
2010-03-22 F26-07L/R Made the AFT fuselage left hand and right hand lower vertical splice plates today.
These parts are very similar to the upper vertical splice plates I made yesterday, they also require a 13.6 degree bend but difference is that these ones have a curved shape as well.

O yeah, if all goes well my 2.5x2.5x.125 angle should arrive tomorrow.
2010-03-24 F03-04, F10-20 and F10-21 Made more 3/16" thick flat pieces from the scrap cut off the 3/16 angle today, 3 spacer blocks, F03-04(2) and F10-20, and the elevator idler plate F10-21.
Today the last of my angle arrived, the 2.5x2.5x.125, but I wont be working with it for another 4 weeks. The day after tomorrow I'll go on hollidays overseas for 3.5 weeks so the project will not progress during that time, these will be the last pieces I've made for a little while.
2010-04-28 Cutting 2.5x.2.5x.125 angle After a 4 week overseas trip today was my first day back working on the project.
I cut all the 2.5x.2.5x.125 angle which I received just before my holiday to length.
These are the last of the angle parts I have to make and it seems there are a few complex shapes amongst them.
2010-04-29 Started F16-04 Started working on F16-04, a support angle on the aft tunnel web assembly. The part was shaped filed and deburred, it still needs the holes drilled and final finished.
2010-05-01 Finished F16-04 Started working on F16-04, a support angle on the aft tunnel web assembly. Just needed holes drilled and a final cleanup.
2010-05-01 F16-06L/R Made F16-06R/L, Left hand and right hand vertical angles that go on the aft tunnel web assembly.
2010-05-01 F10-05L/R Made F10-05L/R, left and right hand seat belt attach brackets.
These are the third set of pieces I've finished today, I needed a good productive day after the 4 week break I've had recently.
2010-05-02 Started F15-01L/R Started working on F15-01L/R, left and right hand upper motor mount angles. These are quite complex in shape to make.
Today I rough cut both the angles with the bandsaw and started filing and deburring them.
2010-05-08 Finished F15-01L/R Finished the left and right hand upper motor mount angles, F15-01L/R.
2010-05-08 F15-02L/R After making the upper motor mount angles I decided to continue and make the lower motor mount angles as well, these parts are also made out of 2.5x2.5x.125 angle and are similar in complexity.
2010-05-09 F15-12L/R Made 2 angle clips today, F15-12L/R. Fairly easy pieces compared to the last ones I made.
2010-05-14 Drawing D02-14 I decided to add the extra a second set of notches to the canopy sliding latch, an easy modification that allows you to leave the canopy partially open while taxiing.
This is not my invention of course, many others have done this before me, however it did take me about an 2 hours to draw the part in AutoCAD until I was happy with it.
2010-05-15 Made F15-07L/R, Left and right hand flap drive mounts. Made F15-07L/R, Left and right hand flap drive mounts.
Nearing the end of the angles, only 1 more piece to go (D02-14) and then I'll have finished all the angle parts.
2010-05-15 D02-14 Finished D02-14 this afternoon, the canopy sliding latch.
This was quite a complex part to make with the extra notches but turned out alright.
This was the last of the angle parts (I think), on to the flat parts.
Regarding the flat parts, I have a surprise there which I unveil once it arrives, should be in the coming week.
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. I recently met a guy from Dandenong who was scratch building a Sonex (# 309) but gave up because he didn't have the time anymore.
This person owns a sheet metal engineering company and thus has access to CNC machines and such to professionally make all his parts rather then scratch build them by hand.
He 3D-modelled all the Sonex flat parts in CAD and uploaded the stuff into the machines and let them do the work.
At the time he made his parts, the Sonex kit wasn't available so this was quite a nice thing to have.

All the parts he made are all the parts I was going to make next, the flat parts; the parts he was going to make next are the parts I've already made, the angle parts.
This worked out great!

Anyway, long story short, after having the parts lie around for many years he finally decided to sell them (very painful decision for him but a wonderful thing for me), and I immediately decided to go check them out and buy them if they were ok.

I've been working on this deal for a few months but since I had the overseas trip recently it took a bit of time.
I paid a deposit before my trip to make sure he would hold the parts for me and last week I finally went over there to see the parts, they looked great and so off course bought them straight away.

Today was the big day, delivery day, the parts arrived at my house!

This will really take years off my project and the parts are made with a precision I could never achieve by hand, it's almost as good as buying a kit, in some respect even better!
Rather then making flat parts for another year or 2, I will be able to start assembly very soon now.

The pictures will tell the rest.
There's an airplane puzzle in my garage!
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures.
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures.
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures.
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures.
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures
2010-05-18 Bought nearly all flat 6061-T6 aluminium parts, CNC-machined / laser cut, holes pre-punched, folded where required. More pictures.
2010-05-22 Making storage space for my new Aircraft puzzle Spent all day today clearing some space under the house and making shelves to store all my newly acquired aircraft pieces.
It’s taking more time than expected but needs to be done, they can’t remain on the floor in my garage.
2010-05-23 Finished making storage space and stored away the pieces Finished making all my shelves under the house today and moved all the pieces down today.
It took all weekend but I’m glad I got it done, back to the real work now.
2010-05-27 D02-13 Since I don't have all the tools yet to attack my new machined flat stock, I decided to continue making some of the thicker flat parts which I still need to make out of the scrap pieces cut from the 1/8" angle. Here's another simple piece, a canopy latch handle D02-13.
2010-05-27 F13-04 Made 2 more pieces made out of scrap cut from the 1/8" thick angle, F13-04 (2 copies).
2010-05-29 F15-08 Only 2 very simple parts today, F15-08.
Basically 2 rectangles, 2" x 0.5" made out of 1/8" thick aluminium.

I've decided to keep making parts for as long as I can before getting to assembly, although I'm not sure if I will last very long, there aren't many parts left to make and I'd realy like to have some airplane looking pieces in my garage soon as well...
2010-05-30 F15-14 2 more easy pieces today, F14-14, doubler support plates.
Not as simple as the 2 rectangles yesterday but not that difficult either.
2010-05-30 F23-08 And 2 more rather easy pieces while I'm at it, F23-08 which will be the seat belt fittings.
2010-06-03 F26-08 Made 2 rudder stop plates, F26-08, again very easy pieces.
2010-06-03 L05-06 This one is the brake handle stop plate.
I'm actually not sure if I will be using the std brake handle at all, I might go for a toe brake set-up in which case I won't need this piece and the handle I already made.
2010-06-05 W13-03 These must be the smallest pieces I've made so far, apart from the 1/8" radius rounded edge, not much to them.
2010-06-05 F14-02 Again, very easy pieces, just so many, took me 4 hours to finish them all!
I had to make 20 of these little rectangle bastards. They are spacers that go between the wing main spars and the ribs, 10 on each wing.
2010-06-07 F15-06 These ones are some of the laser-cut parts I bought from the guy in Dandenong, they are the flap access doublers.
The parts are nearly finished as they come, all they need is some deburring and final finishing.
2010-06-07 F15-11 2 more parts I bought laser-cut, just some final deburring on the scotch-brite wheel and a good clean-up with the scotch-brite pad is all they needed.
2010-06-08 W04-07 I discovered some of 0.90 thick flat the parts I bought were made out 0.125 thick material. Luckely there aren't many and I've got more then enough 0.90 thick spare material to make these and there were more 0.90 parts I still needed to make anyway. Today I started on the aileron counterbalance plates, W04-07, there are 4 of these.
2010-06-09 Continued W04-07 Continued working on the 4 aileron counterbalance plates.
All 4 have been cut and 2 have been deburred, they will all still need the holes drilled. Since I have the uncorrect .125 thick parts I can use as templates, this work goes rather fast.
2010-06-10 Finished W04-07 Finished the 4 aileron counterbalance plates, W04-07. As mentioned before these piece were already made but at .125 thick not 0.90 as required, they're ok now. The .125's will be used as scrap to make smaller pieces later in the project I'm sure.
2010-06-11 W04-04 Made the 2 aileron drive plates today, W04-04.
Again these are pieces that were incorrectly made before out of .125 thick material and not .90 thick as the plans require.
Pretty easy to re-make them since I can use the .125 thick versions as templates as seen in the picture.
There are a few more of these parts made out of .125 instead of .90 but not many. I'll be re-making them over the next few days.
2010-06-12 F15-09 and F15-10 Made 2x 2 fresh 0.90 thick parts today (no re-makes this time).
The lower and upper gear gusset plates, F-15-09/10.
2010-06-13 F07-07 Made the 2 instrument panel corner plates this morning, F07-07L/R.
These parts were also parts I had to re-make because they were originally made out of .125 thick plate and not the required .90 thickness.
The 3/16" hole in the left hand coner plate is where the throttle will be, exiting!
2010-06-13 F10-24 2 0.9 thick gusset plates this afternoon, F10-24.
Fairly simple pieces to make.
2010-06-14 F07-06 Made 2 cross tie plates this morning, these hold the instrument panel and glareshield to the fuselage.
These were new parts, no re-makes this time.
2010-06-15 F10-25 Made 2 very easy rectangular pieces this evening, F10-25, gusset spacers. Didn't even bother to take pictures this time.
2010-06-16 F16-07 Nearly finished with the 0.90 thick flat parts, just one more set to make.
Made 2 shear plates that go on the forward fuselage floor tonight, F16-07.
2010-06-17 F22-07 Made just 2 more very easy rectangular 0.90thick flat pieces, nothing exiting, again not really worth getting the camera out for these.
2010-06-19 F14-10 These are the last pieces that were originally made at the wrong thickness (.125 instead of .90) and had to me re-made.
F14-10, gussets that go on the forward fuselage side panels. Fairly easy pieces but there are just a lot of them, 12.
I found the easiest way to make them was to use a .125 piece as template which was drilled and clecoed to the 0.90 thick plate with 2 holed, then the remaining holes were drilled and the shape was drawn.
2010-06-20 W10-05 W10-05, 2 main spar doubler webs.
These are more parts that I bought laser cut with holes pre-punched (luckely these were made out of the correct thicknes), all they needed was a clean up of the edges on the belt sander and scotch-brite wheel.
With these I've finished all of the 0.90 thickness parts, on to the remaining .125 parts
2010-06-20 F03-03 F03-03, 2 fittings that go on the rear spar carry through assembly.
Again, pre-made, all these needed was a clean-up of the edges.
2010-06-27 W10-03 The main spar center webs, W10-03, parts were bought so only needed the edges cleaned up with sanding belt/paper and scotch brite wheel/pads.
2010-06-27 W13-04 W13-04 2 doubler support plates.
1 of these came with the parts I bought and just needed a clean-up of the edges but for some reason there was only one, maybe it was never made, maybe it got lost. Anyway, I had to make the second one from scratch. Used the first one as a template.
Those big oval holes are always a challenge, you can't drill them because they're not round and too big for a drill. I used my dremel tool with a router extension, works alright but as I found before, you have to hold the dremel tool quite well and be very carefull not to let it get away from you.
2010-06-27 F20-08 Another splice plate, this one holds the 2 forward turtle deck formers together I believe.
Again, this part came with the ones I bought so it only needed some sanding and scotch-brite work.
2010-06-27 F20-09L/R These 2 still needed to be made from scratch. They're attach plates that also go on the forward turtle deck formers.
These needed a 30 degree bend in them which is always a bit tricky, but no drama's this time.
2010-06-28 T09-03 Very simple rectangle, no need to take a picture.
This spacer is only temporary but will be removed on final assembly of the tail, I'll see how that works when I get to it.
2010-06-30 T12-02 Another .125 flat piece.
This is the vertical tail main spar forward strap, nothing fancy.
Only W06-04 and W21-11 remaining and I'll be done with the .125 flats as well.
2010-07-03 W21-11 Made the 2 aileron belcrank plates this morning, W21-11.
2010-07-03 W06-04 Made the 2 flap drive plates this afternoon.
The flap ribs I bought already had the holes drilled so I used those as template, normally you work the other way around drilling the pilot holes in the drive plates but this works as well.
With these 2 I've completed all of the .125 thick flat parts, on to the .190 flat parts.
2010-07-05 channel I noticed I don't have all the ribs for the H/V tail so I will need some channel stock to make these.
This morning I attempted forming the channel over a form block but I'm not happy with the result, I'll either have to get a bending brake or buy the channel from Sonex.
2010-07-05 Cutting .190 flat parts I've only got a 1'x1' piece of .190" plate so I tried to utilise it as best I can. These pictures show about 2 hours of bandsaw cutting. Ready for sanding, filing and deburring.
I could not fit T12-01 and T12-07 on this piece so I'll have to order another 2'x1' piece of .190" plate, in the mean time I can keep busy finishing these.
2010-07-09 F26-04L/R and F26-06L/R I made the left and right hand, upper and lower splice plates today that connect the forward and aft fuselage sections. Unfortunately I made a mistake, I made 2 F26-04L's instead of mirroring them, I should know better by now.
I've got no more .190 thick plate to remake it at this time but I've got some on order since I still needed more for H-Stab T12-01 and T12-07, hopefully it will arrive next week.
2010-07-10 CAD drawing T12-01 Spent some time doing CAD again this morning, drawing T12-01.
Hopefully I receive my remaining .190 thick plate later this week so I can start working on this piece.
2010-07-10 T13-03 T13-03 the rudder drive horn, this part needs a 5.2 degree bend in a tricky place, if you're not careful the bend line will offset on one side. I did foresee this though and with a little more hamering on one side then the other, it all worked out great.
2010-07-10 W13-01L/R It's been a productive day, I also managed to finish the left and right hand aft spar attach plates.
The oval holes are the difficult part here. I used a router bit on my dremel tool to rough cut the holes and then used a half round file and sandpaper to finish them off.
Turned out quite nice.
2010-07-15 drilled and clecoed main spar assembly to 3/32 I'm still waiting for the .190 and .060 plate and sheet I ordered so in the mean time I have started assembling my first part, the H-Stab main spar assembly.
Today I drilled the assembly to 3/32 and clecoed it together, quite a change from cutting out parts.
2010-07-17 F26-04R, T12-01 and T12-07 Yesterday I received my .190 plate and .063 sheet I had ordered so today I started making the last 3 .190 thick parts, F26-04R (the one I screwed up before), T12-01 abd T12-07. All 3 parts are rough cut and still need some filing, sanding, deburring and finishing.
2010-07-18 F26-04R Finished F26-04R, the right hand upper horizontal splice plate.
This part was a re-make, I accidentally made 2 left hand versions before. As shown on the picture, I now now have a left and right hand version.
2010-07-18 T12-01 Finished the vertical tail main aft strap, T12-01.
Little more complex then the parts I've been making recently but nothing like the H stab spar fittings.
2010-07-18 nearly completed T12-07 Filed, sanded and deburred T12-07 the vertical tail forward attach fitting, only needs a 35 degree bend now.
2010-07-18 more work on the main spar assembly Drilled and clecoed the 2 angles on the main spar assembly.
2010-07-19 Finished T12-07 Tonight I bent T12-07, the horizontal tail forward attach fitting.
It went really well, I'm getting quite good at these bends.
I used the same method I used for T06-03, V-block, 1" pipe in the vice, this resulted in a perfect 35 degree bent with a 1/2" radius.
With this last bend I've completed all the .190 thick flat parts, on to the .063 thick parts (there aren't many).
2010-07-25 Drilling the forward spar assembly Drilled and clecoed the forward spar assembly today, it still needs a few clips which I will need to make first.
2010-07-26 T06-06 Made 2 .032" thick clips, T06-06, that need to go on the H-tail forward spar assembly I've been working on.
I received my new 30" bending brake yesterday and these were good pieces to test the brake, even though they are small pieces so I could have just bent them in the vice as I've been doing so far.
2010-07-28 T06-05 Made 2 more clips that will go on the H-tail forward spar assembly, 0.063 thick this time. These clips look easy but I had to make 5 to get 2 I was happy with, the 1/8" radius bend was the problem. I bent them over a 1/4" screwdriver in the vice, but the first tries I always dented the aluminium doing this, making it thinner at the bend, this would make the piece less string so I could not live with this, had to re-make them.
2010-07-31 Installed clips Installed the clips I've been making this week, T06-05 and T06-06, on the H-Tail skeleton.
2010-07-31 T04-01 and T04-02 Not all of the H-Tail ribs were present in the pieces I bought from the guy in Dandenong, T04-01/02 (2 of each) were missing so these had to made by hand, a good test for my new bending brake and my bending skills.
2010-07-31 T04-05 Formed one of the H-Tail tip ribs, these pieces were supplied with the pieces I bought along with form blocks, the forming I still have to do myself. I found the trick is to do a little at a time, don't rush.
This is the first time I got to use my fluting pliers, pretty easy, again a little at a time.
2010-08-01 T04-05 (2) Made the second of the 2 H-Tail tip ribs tonight.
2010-08-01 T04-06 Made the 2 H-Tail leading edge ribs as well tonight, fairly easy once you get the hang of forming ribs. The pictures show the process.
2010-08-02 Started the H-Tail skeleton assembly Started clamping together the H-Tail skeleton and drilled the tip ribs to the main spars.
2010-08-04 remake T04-05 and T04-06 I was not happy with how I drilled & clecoed the tip ribs, T04-05, to the H-Tail main spar so I decided to remake those. While I'm at it I also found my form blocks formed the leading edge ribs, T04-06, a little wide (1-2mm or so), I would have tried them on first but while I'm remaking parts I might as well remake them as well (I'll have to rework the form blocks for these first though).
Tonight I cut all these parts, now they have to be formed again.
2010-08-07 finished remaking T04-05 and T04-06 It took me a few attempts before I was totally satisfied with the shape and size of the H-Tail ribs, T04-05 and T04-06 but I finally have 2 sets I'm happy with.
I had to make my form blocks just a little smaller to get the right size.
2010-08-07 Attached T04-05 to H-Tail skeleton After remaking the tip ribs they had to be re-attached to the skeleton, I'm quite happy with the outcome this time.
2010-08-09 Skeleton, installing ribs Drilled & clecoed 3 more sets of ribs on the H-Tail skeleton, only the centre set remains to do.
2010-08-11 Skeleton, installing final ribs Drilled and clecoed the last 2 ribs to the H-Tail skeleton, I also had a first go at fitting and clamping one of the skins to the tail, seems to fit perfectly, very encouraging.
2010-08-15 Skeleton installing tip ribs Drilled and clecoed the leading edge ribs on the skeleton today.
2010-08-18 Skinning Started skinning the H-Tail, this is quite easy but it took a bit of time measuring, squaring and aligning, again and again and again...
Since this is the first skin I've had to attach on this project I wasn't that confident yet and wanted to make absolutely sure all was correct, it was.
2010-08-21 Skinning (2) Attached the other side of the left H-Tail skin to the skeleton and updrilled all the external holed to #30.
2010-08-24 Skinning (3) I took the LH skin back off the H-Tail to bend it a bit more, I found there was too much force required to pull the skin against the ribs, even the clecoes were not able to keep the skin tight against the tip rib, after a bit more bending it fits much better.
I did the same to the RH skin and attached it to the skeleton, did not finish this job tonight though, needs a few more holes and clecoes on the bottom side, I'll do those tomorrow night.
2010-08-25 Finished skinning, attached piano hinge Finished drilling and clecoing the skins to the H-Stab tonight, I also attached the piano hinge half for the elevators to the assembly.
2010-09-04 updrilling skeleton After being away on a business trip for a week I got right back in to it.
Took the skins back off the H-Stab skeleton and updrilled the skeleton to #30.
2010-09-04 deburring Deburred all the holes in the H-Stab skeleton.
2010-09-05 Priming parts Primed all the parts of the H-Stab skeleton. I've decided to use a Tempo zinc phosphate primer with a PreKote base.
This is different from my initial strategy which was a zinc chromate primer with an alodine base.
I did already buy 500g of alodine 1200S but after reading about the toxicity of these chromate based products and the hassle of disposing of the stuff when you're done with it, I decided to use a more environmental (and builder-) friendly option.
Here's the process, clean all the ink off the parts with acetone, clean the parts with dishwashing detergent, dry, apply the PreKote and scrub in with a scotchbrite pad, apply PreKote again before the first layer dries, rinse with water before second layer of Prekote dries, dry, prime within 24h.
The PreKote process is quite time consuming but still better then the alodine option which requires 2 more steps.

I think I might have been a bit too generous with my primer (which comes in rattle cans) but I hear that's a common mistake, by the time I got to the last parts I got the hang of it and applied a lighter coat.

Now it's a matter of letting the parts dry and then I'll be pulling my very first rivets of the project, exiting!
2010-09-10 First rivets I pulled my first rivets tonight.
I had my neighbour, who is also my SAAA technical councillor (quite handy), come over to check out the few practice rivets I had first pulled in a piece of scrap aluminium to find the ideal PSI setting for my pneumatic rivet gun. Seems around 40 PSI is the best setting for my gun.
My TC was happy with what he saw and so we went on and pulled the first rivets of the project on the H-Stab forward spar assembly.
Actually nothing to it, it seems the riveting goes quite fast compared to all the preparation that has to be done beforehand.
2010-09-11 Riveting the skeleton Finished riveting the H-Stab skeleton this afternoon, like I said before, riveting goes quick, a lot quicker then all the preparation that has to be done to get to the riveting stage.
2010-09-12 deburring skins Deburred all the holes in the H-Stab the skins tonight, but before I could do that I had to take off the plastic protection, this took me about an hour, very frustrating job, goes a little easier when heating up with a hair dryer but still...
Anyway, the skins are now ready to be cleaned, prekoted and primed (on the inside that is, I'm planning on polishing the outside).
2010-09-15 Priming skins Scuffed, cleaned, PreKoted and primed the insides if the H-Stab skins tonight.
2010-09-18 Riveting the skins (1) Finally pulled the skins over the H-Tail skeleton for the last time and riveted them permanently.
Got Nathalie & Jur (my wife and a good friend from Belgium on a visit) to help me achieve this major milestone.
With this finished the first airplane looking part (up till now you could not tell whether I was building a plane or a boat).
2010-09-18 Riveting the skins (2)
2010-09-18 Riveting the skins (3)
2010-09-22 Making ribs Made the ribs for the elevators and the rudder tonight
2010-09-23 Drive assembly Drilled and clecoed the rudder drive assembly together.
2010-09-26 Clecoed elevators Drilled and clecoed the ribs to the elevators
2010-09-27 Continued elevator assembly Installed the drive horn assembly and the piano hinge halfs on the elevator assembly. I still need to make and install he trim tab on the assembly and then I can start updrilling to #30.
2010-09-29 Started working on the elevator trim tab Drew the trim tab in CAD, spray glued it to the aluminium and cut it out tonight.
2010-09-30 Finished the elevator trim tab Finished the trim tab tonight.
The previously cut out shape was deburred and bent as required.
I made the piano hinge, drilled clecoed and then riveted it to the trim tab, done. Too easy!
2010-10-03 Attached trim tab to elevators Drilled and clecoed the trim tab assembly to the elevator assembly.
2010-10-03 Updrilling elevators to #30 Updrilled one side of the elevators to a #30 drill size.
2010-10-04 Finished updrilling the elevators Finished updrilling the elevators to #30 drill size this morning.
I've also taken the assembly apart again so I can start deburring this afternoon.
2010-10-04 Deburring Deburred the elevator skins, ribs, hinges and horn.
First off course I had to pull the plastic protection off all the aluminium parts which takes ages.
Next: PreKoting & priming
2010-10-08 Priming parts Acetoned, detergent cleaned, prekoted and primed my elevator parts this afternoon.

While I was waiting in between prekote & primer for parts to dry I started polishing my H-Stab as well. It started to look quite good but then my cheao ebay car polisher broke, oh well it only cost me $35 incl. shipping, I'll go look for a better one tomorrow.
2010-10-10 Riveting Assembled and riveted the right elevator, I can't do the left one yet since I'm waiting for an anchor nut I ordered, this nut goes on the inside of the leading edge rib on the left elevator.
2010-10-11 Polishing Did some more polishing work on the H-Stab while I'm waiting for an "anchor nut" to finish my elevators.
Wow, this is indeed slow I've now only done the top side with the Nuvite F grade once, I'll have to go over again with the F grade I think and the with the C grade, hell of a job but I already like the results.
2010-10-16 Rudder drive horn assembly I'm still waiting for an anchor nut to be able to finisj my elevators so I started working on the rudder.
I finished the rudder drive horn assembly today. I had to re-make T12-04 3 times, first time I cut too far into the piece, second time it looked ok but when I wanted to drill & cleco it to the assembly I realized I had mirrored the piece, third time was ok.
2010-10-18 Rudder assembly Drilled and clecoed the rudder together this morning.
2010-10-18 updrilling rudder Updrilled the rudder assembly to #30 and taken it appart again for deburring.
I started peeling off the plastic protection from the aluminium as well but only got halfway with that, that's a hell of a job...
2010-10-18 Peeling! Grrr! Spent more then an hour peeling off the protective plastic from the rudder skin and ribs to get ready for deburring
This is a painfull job anyway but it seemed to be extra painfull this time, not sure why.
Usually it goes a little easier using a blowdryer but that did not help to much this time, in fact around the stamps from the mill on the aluminium where the plastic sticks the most the blowdryer actually made the job worse because it made the plastic tear.
Anyway, the job is done now, on to deburring...
2010-10-19 deburring Deburred the rudder skin ribs and other components tonight, ready to clean, prekote & prime.
2010-10-21 Polishing I received my new polisher today, after breaking 2 cheap ($35) car polishers I decided to buy a heavy duty automotive polisher off ebay.
The wool pads alone for this polisher cost more then the old cheap polishers but it's well worth it, I polished one more side of the H-Stab tonight with the F grade, seems to go much easier then with the cheap polishers (but still a hell of a job though).
2010-10-23 Priming Cleaned all the rudder parts with acetone to remove the ink, then with detergent, treated the parts with PreKote and finally primed all the parts.
2010-10-23 More polishing While I was waiting for my PreKote treated rudder parts to dry, I did another polish pass with the F grade on one of the H-Stab sides. Soon I'll have to move to the C grade, I don't seem to get much improvement anymore with the F Grade.
2010-10-24 Tail tip ribs Made the ribs for the fibreglass tail tips this afternoon.
First had to make form blocks out of wood and then cut the ribs and form them over the blocks.
2010-10-25 Elevator horn assembly continued The anchor nuts required to finish the elevator horn assembly finally arrived today so I got straight in to it and drilled/countersunk the holes for the nut in the assembly.
I also primed the bare steel after that and I will probably also use duralac for extra protection of the steel.
Finally I'll be able to finish the elevator assembly.
2010-10-27 riveting Clecoed the rudder and drive assembly back together and started riveting tonight.
2010-10-28 Riveting Finished riveting the rudder tonight.
This will now be stowed away under the house until I finish the V-Stab.
2010-10-30 Assembly and riveting Finished the elevator assembly this morning.
The parts had been sitting there for a while ready to be assembled but I was waiting on an anchor nut that fits on the inside of one of the root ribs so could not assemble until I received this nut, which happened this week.
2010-10-30 Polishing Polished the whole H-Stab with the C-Grade now.
I'm still debating if I'll continue to the final S-Grade already or wait until assembly, most people wait just till just before assembly since you'll have to lightly touch it up anyway then.
Anyway, the results already look amaizing.
2010-10-31 Fitting Started fitting the H-Stab tips, this is harder then I thought.
2010-11-03 Fitting Continued fitting the tips.
As many builders before me, I finally decided the tail tips do not fit well enough to slide between the skin and outer rib so like all those builders before me I decided to slide a piece of .032" metal between the skin and rib instead and attach the rib this way, much better fit.
I completely fitted the left rib, dilled to 3/32", still need to complete the right rib though.
2010-11-06 Fitting I took the H-Tail tips back off today.
after matching the elevators I noticed the tips are sticking out passed the elevators about 1/4".
I could live with this but I decided I'll reduce the tips in width about 1/2" which will automatically decrease in length.
I'm starting to hate this fibreglass work, realy messy.
I'm glad I chose to build an aluminium plane with little fibreglass rather then a full fibreglass plane.
2010-11-10 Fitting More fitting work, I think I got them just right now, I had to remake the aluminium extensions again, I now just neet to trim out 1/8" for elevator clearance.
2010-11-14 trimming and drilling Trimmed the H-Stab fiberglass tips and drilled and clecoed them to the tail. Finally they seem to fit nicely. Hopefully this goes a bit quicker on the V-Stab.
2010-11-16 up-drilling and deburring Up-drilled the tips and aluminium attachments to #30, took everything apart and deburred the attachments.
2010-11-18 cleaning prekoting and priming Cleaned the H-Stab tip attachments with acetone then with detergent. Prekoted them and finally primed them.
2010-11-20 putty Some of the holes drilled in the fiberglass H-Stab tips had some inperfections on the surface around so I fixed these up with some miliput putty.
2010-11-21 Riveting attachments Riveted the attachments for the tips to the H-Stab, I will now just do a final polish of the entire H-Stab before attaching the tips. I'll paint the tips later though, I could have painted them now before attaching but then the rivets won't be painted along.
2010-11-23 Polishing Before I put the tips on I will polish the H-Stab one more time with the C grade, tonight I did the left bottom side, I also had to work out a few scratches I made when fitting the tips.
2010-11-24 Polishing Polished the right bottom side of the H-Stab with the C grade one more time
2010-11-26 Polishing Polished the left and right top side of the H-Stab one final time with the C grade.