PB Models Chevron

Cloud Models

RM Test Report

24. Wing repair
Finish not as good as the original, as I didn't want to remove too much covering. The Profilm join is hidded by some cut vinyl chevrons. (Do you see what I did there)
24. Fuselage repair
With the structure sound, it was a matter of several rounds of polyester filler and sanding, followed by top coat and Klasscote clear as fuel proofer / laquer
23. Fuselage repair
I made a fibre glass nose ring and with the engine fitted centred it and glued it in place. This then gave me the shape and position of the nose which was re built with glass cloth and polyester resin (No foam to worry about here and polyester is cheaper than epoxy)
22. I broke it
No picture of the wings before I started the repair, but here you can see the initial repair. The front was crushed and the wing bolt holes were torn out. Gorilla glue did the trick of filling out the crushed foam inside the wing.

I glued all the bits back to retain the shape, filled with epoxy filler, and wrapped more glass cloth with epoxy. I uses a double thickness at the mounting holes.
21. I broke it
I did an outside loop (bunt) from the top, I got round to about 10 o'clock when the engine died. By the time I got to the top I had zero airspeed, and it fell out of the sky. Wasn't sure whether I was going to repair or not so put it to one side for a few weeks. The nose was completely gone and there were stress cracks all the way down the fuse.
20. Fuselage completion
Completed model waiting maiden flight.
19. Fuselage
Engine fitted, I copped out on the cockpit, I opted to spray the inside of the canopy lightly with car lexan spray. Would have liked a different colour but blue is all I had.
18. Fuselage completion
Fuselage sprayed is metalic base and Klass Kote clear epoxy top coat. rear end showing the elevator servos.
17. Fuselage spraying
Fuselage primed and flatted back with 600 grit wet & dry.
16. Canopy
Careful repeated marking and small cuts to get the canopy to fit the mounded frame.
15. Tailplane & Fin
A couple of old draughting squres used to set the fin at 90 degrees, and a shot of the completed rear end with the servo holes.
14. Tailplane & Fin
Tailplane aligned and glued, followed by careful making out and cutting for the fin.
13. Wings
Completed wing fitted and aligned to the fuselage, clamped and drilled through as one, for the wing mount. I like 2 wing bolts it prevents the wing from twisting in the seat. That said there is little change of movement as the wing is a snug fit into the fuselage.

1/2" dowel used to make hardpoints for the aileron horns, there will be nothing showing on the top wing surface.

Covered in white Profilm, ready for trim.
12. Tailplane & Fin
Both the tailplane / elevator and fin / rudder were glued together, the moving control portions with a tack of white glue. They were then shaped and sanded to shape, and then the contols are separated.

I'm going to use a servo for each elevator half - makes it easier because of the geometry, and this worked well on my Curare.
11. Problems with kit
Now this is a shame and does show where the eye has been taken off the ball. There is an issue with the saddle clamps and undercarriage wire.

Firstly the saddle clamps don't fit the undercarriage, and secondly the wrong type of clamps were supplied for the main undercarriage.

From the plan the main undercarriage blocks have a recess for the wire, in this case flat saddle clamps are fine, but in this kit the mounting block don't have this recess so need shaped clamps the undercarriage, but flat ones are supplied.

There are shaped saddle clamps supplied I think for the nose leg, but the undercarriage is a substansial 6SWG and the supplied clamps are 8.

Its not a biggy but the quality of the rest of the kit is so good I was supprised at this slip up.
10. Engine Mounting
Mount glued in with the engine and spinner mounted, at this stage the glue on the firewall is still wet allowing me time to align the spinner to fit the fuselage. It was then left 24 hours to cure. Once set I was able to remove the engine & mount and I mixed some more epoxy with micro balloons and with some gentle heat ran some more glue into the joint.
9. Engine Mounting
Engine mount offset from centre to allow for right thrust and still have the prop on the centre line. I dry fitted F1, engine mount , engine and spinner to make sure it all lined up. When I was happy it did, I reassembled with a slow setting epoxy. Aralide 24 hr being my glue of choice.
8. Tailplane
There seems to be a small issue at the rear between the supplied fuselage and the plan. The fuselage at point A & B where the tailplane fits is shallower than that shown on the plan, this means that the thickness of the decking at point C is almost zero. So rather than use the supplied 18mm ssquare block to make this decking I've used some 1/2" sheet, and put the larger block in the wood box for another day.

Its easier to shape the decking with the sacraficial dummy tailplane placeholder than with the actual tailplane fitted.
7. Fuselage
Preliminary cutout for the engine in the glass fibre fuselage, Note I have cut a hole in the cockpit floor to aaid access The second pic is of the rear decking manufacture, I have a dummy piece the same thickness as the tailplane with the block to be shaped on top. There is a discrepancy between the plan and the supplied fuselage. More on this above.
6. Wing correction
Cutting the ailerons to suit the plan, and not checking the position of the now straightened servo holes mean that there isn't enough room to fit the aileron horns. Should have make the ailerons an inch or so longer. I have fixed this, but have to tack the off cut to the aileron, this was fitted on the outboard side so there is no stress on it from a hinge.

Third image shows the centre section glassing with epoxy, also note I have glassed the wheel mounting blocks to the veneer wing skins.
5. Tail bits
Tailplane and fin built over plan and sheeted
4. Wing
Centre section with the tip parallel, no misalignment. Do make sure the wings are upside down.
3. Wing
As per my other builds this is how I join the wings - it is important that the tips are parallel, to achieve this I draw a line through the centre of the wing tip and glue a parallel piece of wood to give the desired dihedral. The wings are joined with the top surface flat to give a small natural dihedral, so the tip pieces just touch the thickest part of the tip section.

With the wings on a perfectly flat surface hold down the tips; what this does is it makes sure the tips are parallel but more importantly they are exactly in the same plane. Any errors will now be at the centre join. There is nothing you can you about this, but the errors will have a lesser effect than at the tips. I'd suggest that if there is more than 5mm error between the 2 panels you request another pair from the manufacturer.

I'm please to say that there was no error at all, 2-3 mm is usual so these panels are exceptional.
2. Wing
Although a bit blury you can see the pre cut hole for the wing servos. I have changed the orientation to put the servo 90 degree to the aileron, just something I like to do to make the set up geometry easier. I mentioned this to Paul Bardoe, and he is going to look at correcting this.

The next shows the undercarriage mounting plate epoxied in place and the servo wells at 90 degrees and sheeted.

For the top undercarriage mount I have increased the hole depth and topped the ply mount off with balsa. The balsa will sand easier to match the veneer sheeting.
1. The kit
Just arrived - PB re kit of the Chevron. Initial thoughts are its a very good kit. Initial thoughts are its a very good kit. I've only opened the box and un wrapped the fueslage, but liking what I see so far.

You get: Gel coat finished GF fuselage that is supurb quality A pair of foam wings with the veneer around the leading edge, and cut outs for servos and undercarriage mountings. A selection of balsa which looks well matched A limited hardware pack with good quality horns / wing joining bandage / undercarriage mounts / screws an a length of mylar Canopy wrapped to keep it free from scratches A rolled plan which looks to be a copy of the original (there is even mention of Sprengbook servos). Cool.

There are no instructions - not a real problem as this is not a beginners model, but migh proove helpful if its your first go at a kit build. I'll be starting the build slowly over the next few weeks, as I have some other models to complete (I know I say this every time).