Valdez Stol Record breaker build blog

[Tim C]

I have airbrushed a cote of Cub yellow on the rudder as a test of the paint and colour.

Just as Ferrari’s have to be red, Land Rovers Green ( despite my current one being blue!), Cubs need to be Cub Yellow. Cub yellow is a much disputed colour, but widely accepted that Lockhaven yellow is the correct colour. Using a colour chip found on the internet I converted the code to one that Homebase can use in there Dulux colour paint machines, £3 and I was in possession of a 250ml pot of Lockhaven yellow, well the Dulux equivalent .

For spraying I mixed up some paint with 10% of Floetrol and thinned with Lidl window cleaner to a consistency the would spray with my airbrush, I was pleased with the colour, which looks correct in my eyes, and it flowed and sprayed on well, it’s only one coat so far, it will probably need 3 thin coats to provide an opaque finish, no primer is used, I will finish of with a final coat of Matt clear WBPU to seal the surface.

 

 

Edited By Tim C on 09/04/2019 14:35:20

[Tim C]

Not a lot of progress this week due to major plumbing disaster, water coming up through kitchen tile floor due to burst pipe in the screed, eeek!

anyway manage to finish of the tail group and get it hinged ready for covering, I do like the mini hinges from Banggood

Edited By Tim C on 13/04/2019 09:13:36

[Dwain Dibley.]

Hi Tim,

Great Blog........

What weight covering did you use, there are 15g, 25g and 35g per sq M available at free flight supplies.

Thinking of using this on my Cessna 120, so I can use a chrome paint ???

Cheers

D.D.

[Tim C]

Covering in Polyspan. I use the 25gm version, I have trialled the heavier 35gm type, but concluded no real benefit, this version has a threads running one way as extra strength, this hinders shrinking as is more uni directional, and tear strength is only improved across the material, not much different the other way.

stage 1 is to cut out a piece of material, make sure shines side up, I use a circular cutter, easier than scissors.

[Tim C]

Next is to coat the balsa in glue, I use impex, brushed on slightly diluted and left to dry.

[Tim C]

Tacking with iron, then seal down all the edges, shrinks well around the curves

Cover with the polyspan, just place over the top shiny side up and tack withe iron, I use about 130c

[Tim C]

I then run to iron to seal the trimmed edges, and a quick run to shrink the covering, all ready for the top side covering.I use a double edge razor blade for trimming, just tape over 1 edge to protect the fingers

[Tim C]

I am getting behind with both building and posting on the blog. A plumbing disaster, bust hot water pipe in the solid floor in the kitchen and a holiday away caused work to stall.

I have nearly finished the wings, and have been working on the flaps and ailerons. I designed a flap hinge which I printed on my ANET A 8, this gives a slotted flap, it will be screwed and glued on final assembly. The pics show the trial version. I used a M2 hex bolt and nut for the pivot.

[Tim C]

More detail of the hinge

[Tim C]

Hinge in action

[Stuart Quinn-Harvie 1]

Well done for getting this far with a flooded house. All looking good so far. Will the hinges be available to purchase or the files to download? ( for a fee of course )

[Tim C]

I will post up a link to download the STL files for the parts I use, so far it’s the end rib and flap hinge.

[Tim C]

Link to the Rib and Flap STL files

One Drive link to STL's

[Tim C]

As I am awaiting the glue to dry on my Li’l cub slats, I came across this old article on slats in RC models.

8

[Peter Miller]

Based on how mine flies I must have got it right. I did know about the equal openings not being correct.

[Tim C]

While progress on the airframe continues, I have been fiddling (and learning3D design).

This is my cartoon attempt at a 3D printed dummy motor for the Cub. It not printed as a single part but a kit of bits glued together. The crankcase is a snug  fit over the motor X mount, and I will sort out a rear mounting tab in due course.

I have still the cooling ducts and inlet and exhaust pipes to do, but they will wait until I got it mounted up on the firewall so I get a better idea of proportions and sizes, test prints of the various parts look promising.

 

Edited By Tim C on 14/05/2019 15:45:38

[Steven S]

Tim - are you building your version to the plans at just under 1:6 scale? And are you going to make all your 3D parts available to us? I am getting ready to build one also and am following your progress. I have been following the pictures on your album, very nice work so far.

Edited By Steven Shaw on 14/05/2019 16:41:09

[McG 6969]

... splendid work all over, Tim.

Cheers

Chris

[Tim C]

I have posted up a link in an earlier post to a one drive share with the STL files so far, i will add the motor files in due course.

They are to fit the standard version of the plan.

if anyone wants the 123D files to mod the parts I can make these available

[Stuart Quinn-Harvie 1]

Thanks for the link, Tim

[Tim C]

If anyone using the 3D printed rib profile, this is not quite as on the plan, I made the top spar vertical so I could add webbing, and the TE is 1/8 rather than 1/4 , the plastic part makes an excellent template to cut the other ribs.

[Tim C]

[Tim C]

As the crankcase came of the printer

After rubbing down, 2 coats of Halfords auto primer and 2 coats of dulux airbrushed on, will finish with coat of lacquer. Cylinders just temp awaiting finishing, just stuck on with double sided tape for the moment.

[Peter Miller]

That looks very good!

[Tim C]

A bit more done on the dummy motor, faked carbon effect on the cooling vent, LH one awaiting finishing