Pieter Visser's X350

[Pieter001]

This morning I sanded the inside area on the vertical spar planks where I had put the flox bead and did the 4 layers of 410 bi-ax E glass layups, finished with peel ply. It worked out perfectly
The glass cut pattern for this is simple: measure the middle from top of front spar plank down the trough and up to the top of the rear spar plank. Mine was 24cm here and then the length was 120cm and at the ends it was 11cm. So this one draws out and cut to. Remember to make the center 24cm 16cm long, as this goes over the ply wood load spreaders
I also like to have center lines on the glass, which I find make it easier to lay the cloth correctly, as I mark the center line on the spar stubs (on the packaging tape) before the layup and hence all the black lines one sees.

I made sure to again level the wings with zero incidence and aligned with the laser, as well as checked the dihedral, before I did this layup.

[Pieter001]

I've removed the spar box and cleaned up the edges in preparation for the plywood load spreader and final UD layups. I managed to put the spar box back on the wings without too much trouble

Spar box cleaned up and ready for spacers and UD

[Christiaan van Zyl]

Looking good Pieter! Keep it UP!

[Pieter001]

Thanks Christiaan, will do

Really want to get the air frame done this year, so 2018 is going to be a busy one!

I've cut all the glass needed for the top of the spar box, fabricated the plywood load spreader and rounded and sanded the area on the spar planks where the final 4 layers of 410gr bi-ax have to go. Tomorrow I need to trim the plywood a little to fit perfectly and then cut the foam and do the layups. This is going to be a quite a task and I look forward to getting it done!

Cut plywood to lengths, but need to even it out a little after this stack has cured

Sanded, rounded the top plank edge and cleaned all areas for the final layups

[Pieter001]

I had some time and trial fitted the elevator pulley brackets. I used the 8mm eye bolt meant for the wing tie down points, as I'm still waiting for my AN hardware to arrive. Seems A-Spruce is struggling to source and supply me rivets, which is on the same order

To drill the holes in the fuss from the top, I made a little paper template by tracing the bracket onto the paper and marking the holes. I then cut out the template and pierced holes with a pen in it where the bolts should go. Making sure the right side is up, I then stuck the template in the position where I wanted it on the fuss and used a silver pen to mark the bolt holes on the carbon layer on the fuss. Initially I drilled 4mm holes and used 4mm bolts and nuts to trial fit, but it was perfectly aligned first time. I then removed one bolt at a time and drilled the open hole to 6mm and then reamed it to 1/4", immediately fitting the AN4 nut and bolt, before moving onto the next 4mm bolt. This ensured everything fit like a glove

[Pieter001]

Today was d-day for the top part of the spar box and I am really happy to have completed this step. Took a little sanding and shaping to get the plywood and polystyrene to fit just right. Found the RH side polystyrene had a low spot, so added a bit of flox between 2 layers of UD to take up some of this low spot, which worked well, but it's hard to get the flox layered evenly.

All said and done, I'm happy to have this completed and the job looks pretty good in the end

Flox used liberally to bed the load spreader down

Polystyrene fillers shaped

Finished with peel ply

[Pieter001]

I've encountered a problem with my LH wing bolt, which is stuck in the wing spar box... Now before anyone thinks this is a Epoxy in the wrong place issue, rest assured it is not

I've removed the wing bolt from the wing box after the last layups were done, but while doing so, I noticed the nut seemed to come loose, so I used a pair of pliers to assist with the removal of the bolt. What has happened was that the weld behind the nut was not sufficient to keep the nut from "slipping" over this, but in doing so, it destroyed the nut thread I discovered.

I originally thought to just screw it tight and to have the weld redone, so I screwed it tight again (wing box removed) and after a re-think, decided to take it apart again, but then the nut came away clean from the bolt and revealed the stripped thread etc. So now the bolt is stuck and tomorrow I'll take it to an engineering shop to sort it out. Sadly, I have precious few tools at this time

Bolt stuck in tight position with nut and washer off

[Pieter001]

As I'm not working on the wings, I potted around with odds and ends, as I only had 1.5 hrs of time today and I actually wanted to do the aileron bell crank layups, but that will take at least 3 hrs I estimate.
I rust proofed the 304 stainless bumper washer and small washer, which is used in the elevator pulley assembly and floxed them in place. Carbon is great, but it causes corrosion, unlike fiber glass, hence the rust protection

I also used an angle grinder and drill (have no lathe) to trim 8mm stainless long nuts down to 12mm, which with eye bolts will be tie down secure points under the wings near the tips.

Lastly, as I had some resin left after the wee bit used for floxing the washers, so I sanded the fuss around the cockpit where the ballistic cables should run, made a micro mix and started filling in this angle. I won't be installing a ballistic system.

Rust proofed washers and prepped long nuts for wing eye bolts

Washers floxed in place

Micro to square the ballistic cable rail

[Pieter001]

Frustratingly, not much happening at the moment. I'm still waiting to get the wing bolt sorted.

As I've put the new carbon V-stab fin skins on, I refitted the rudder and started trimming the skins to suit. I've placed an order for 0.25mm x 50mm Teflon (PTFE) tape (R2860.00) equivalent for 30m roll ! Plan is to put this on the end of the fin skin to prevent chafing on the rudder. I'm also toying with the idea of using this to make aileron and flap gap sealer

I did do the aileron bell crank bracket layup today. Used 9 layers 300gr bi-ax carbon and 3 layers 410gr bi-ax e glass, where I started with peelply, 1 glass, 4 carbon, 1 glass, 5 carbon, ended with 1 glass and peelply. As carbon causes corrosion, the layup is started with glass and ended with glass to help prevent any chemical corrosion. This is a very strong and thick layup!!

Aileron bell crank bracket layup

[Pieter001]

I got my wing bolt back today
Started making the aileron bell crank bracket from the carbon & glass layup. I measured the holes from the back ridge at 79mm by pressing the layup flush with the wall and measuring from the wall. I then drilled this hole in the drill press (just bought one this week ) through both sides of the layup. Then measured and cut the layup using the angle grinder with a 1mm steel disk. Finally used a flapper disk to smooth the curves. Came out pretty well
Tomorrow we'll change the wings over to start the bottom of the spar box. Going to be a busy weekend