R

roee

Well Known Member
I'm having trouble fitting the flap actuator weldment and plastic bushings.
The distance between the end sections of the weldment (the area that's not
powder coated) is 3/16" longer than the distance between the inboard faces
of the plastic bushings in the fuselage. Or stated differently, 3/16"
of the powder coated area would have to insert into the bushings to fit in
the fuselage. Now, it's not the powder coating per se that's causing a
problem. It's the weld fillet which also ends right where the powder
coating ends. So the weld fillet is what prevents the tube from going
further into the plastic bushing.

Has anyone else run into this issue? Anyone talk to Van's about it?
Suggested solutions?

I don't want to grind down the welds and make them weaker. I'm thinking
maybe machine out the plastic bushings to clear the welds, but I'm not so
enthusiastic about that either... I want to first identify the source of
the misfit.

P.S. Would someone send me some measurements so I can compare to mine? I
want to know the distance between the inboard faces of your bushings, and
the distance between the outboard edges of the outboard weld fillets on the
tube.

Thanks!
-Roee
 
distance between *outboard* faces of bushings is approx 41 5/8 on mine... (you can figure out distance between inboard faces from this measurement). I didn't have that problem you described.
 
That sounds right

Thanks Radomir. The bushings are each 3/4" thick, so the distance between the inboard faces is approx 40 1/8".

Yep, that's consistent with mine (actually yours is even slightly narrower than mine). So I'm confident that the bushing blocks are positioned correctly, which I was pretty sure of anyway because they're just centered with the pre-punched holes in the bulkhead.

So that brings us back to the weldment. The measurement above means that the distance between the outboard ends of the weld fillets must be 40 1/8" or less. On my weldment it's about 40 3/8". So that would indicate I have a bad weldment?..

Radomir (or anyone else)- what is that measurement on your weldment? Or alternatively, how much clearance is there between the weld fillets and the bushing blocks?

Thanks,
 
I put mine in 2 nights ago and no problem like that. I did notice that the center block, F-680 appears to be backwards on the drawing. If I installed as per the drawing, the front end would be suspended over the aft seat floor.

Speaking of the aft seat floor, the plans tell you that the edge can be over or under the baggage floor, builders' option. Put it OVER so the flap block fits better. The cut out portion of the block will fit nicely as drawn if the seat floor is over the baggage floor but, will need additional trimming and fitting if you do it vice-versa. I learned the hard way.

Also learned the F-680 is not as easy to install as it looks. As a result of the non-parallel nature of the underlying structure, the anchor nut is a real bi-otch. Ultimately, I had to tap the anchor nut so I could insert the bolt for use as a clamp. Now I need to get some AN3H-22A bolts so I can safety wire the heads as the anchor nut lost most of its drag.

Scratching my head over the F-680 delrin block.

Jekyll
 
I agree that this may be a bad weldment... my blocks are VERY close to the weld filet.... almost touching 'em...

You may want to check the arms that extend back and hold flap pushrods. Here's a measurement -- 39 5/8 - this is outboard to outboard faces of the "fingers" that hold flap pushrod (flat areas that is used to bolt the rod-end on the weldment side). Hopefully I described well what I measured. Wondering if yours is just too wide there?


PS. If this is a bad weldment, I'd return it and have them exchange for another one..
 
I looked at mine again last night and the weld fillet does touch the delrin. As other have said, the fit is tight but, I expect it to loosen up with age and use.

Jekyll
 
Resolution

Thanks all for the replies.

After carefully studying the measurements and consulting with Van's, I concluded that all the basic measurements were correct, but the welds were sloppier than normal and extended further than they should have. I ended up beveling out the bushing blocks slightly (Van's agreed this was ok), which did the trick. I used a 45 deg router bit from home depot at 3000 RPM, worked great.
 
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