Center spar wing bolts for RV-10

PrescottB787 · #1 07-25-2018, 03:41 PM

I?m building the fuselage before the wings and had to order the center spar with the fuselage kit. . I don?t have the wing bolts for the center spar (the bolts and nuts come with the wing). I was wondering if anyone did this and what bolts and nuts they use? Is a smaller size ok? Or, should I order the nuts and bolts from Vans that fit exactly? Appreciate any help.

Ken

ctennis · #2 07-25-2018, 03:50 PM

Quote:

Originally Posted by PrescottB787

I?m building the fuselage before the wings and had to order the center spar with the fuselage kit. . I don?t have the wing bolts for the center spar (the bolts and nuts come with the wing). I was wondering if anyone did this and what bolts and nuts they use? Is a smaller size ok? Or, should I order the nuts and bolts from Vans that fit exactly? Appreciate any help.

Ken

I too am building the -10 fuse before the wings, and am not to a step where I need bolts yet, but from building an -8 before I will say you definitely don't want to put the final bolts in until the last step. They're close tolerance, and a very tight fit. It's very difficult to get them back out without using hammers and taps.

Use some temporary bolts from the hardware store for fitting things until the final time you want to do the installation.

PrescottB787 · #3 07-25-2018, 03:55 PM

So everything lines up well enough for when you put the permanent bolts in??

Mike S · #4 07-25-2018, 04:05 PM

Are you talking about the bolts that are outboard of the fuse ------ that attach the wing to the carry through? These are close tolerance bolts, and it is good to only use them on final assembly

Or (as I suspect), the bolts that attach the carry through to the interior of the fuse tub?

PrescottB787 · #5 07-25-2018, 04:10 PM

Yes, that?s correct. Just worried about them not being aligned when I put the wings on.

Ken

Mike S · #6 07-25-2018, 04:19 PM

Read ahead in the plans, pretty sure I remember this being addressed.

IIRC----Basically you make up wooden spacers that simulate the wing spar stubs, then assemble the carry through, then build it into the fuse tub.

PrescottB787 · #7 07-25-2018, 04:54 PM

On Page 28-9 it refers to page 44-11 for the hardware. It?s the final nuts and bolts for the wings. They supply spacers for now and I assume after it is assembled I make the wooden spars?

ctennis · #8 07-25-2018, 05:12 PM

Yeah, my recommendation is to not use the final bolts at this point. It will be painful to get them back out again, and you will also want to have some "temporary" hardware for fitting the wings once or twice before you put the actual final hardware in.

The bolts are

NAS1309-58 (9/16 diameter, 3 10/16 grip length)
NAS1306-58 (3/8 diameter, 3 10/16 grip length)

Cheapo grade bolts and nuts from the hardware store will work just fine here, imho. The match hole drilling with keep parts nicely lined up, and the only real critical piece is the space between the spars, which the spacers do a nice job of holding for you.

On the -8 you have to build you own spacer out of wood, and to a 1/32 of an inch!

terrye · #9 07-25-2018, 06:12 PM

Well if the RV-10 plans still specify a wooden spacer, they should re-think it. This spacer sets the distance between the spar carrythrough halves so the wing spar can slide in during final assembly. I machined mine out of delrin (or acetal) plastic so the material was dimensionally stable and didn't swell from absorbing water. Measure the wing spar thickness then add .005-.010" for the spacer thickness.

flion · #10 07-25-2018, 06:26 PM

You should have aluminum spacers (and a machinist friend of mine mic'd them with the plastic on and off - definitely peel the plastic before using them). Use common bolts for now and replace with your close-tolerance bolts at final assembly. See section 44 of the plans, especially pages 44-3 (where modified hardware bolts are used as drift pins) and 44-11 (which discusses the installation of the NAS bolts. You should ream only as a last resort and only after as many of the bolts as possible are already inserted. If a bolt won't go, first try other bolt positions. Definitely do not ream if you don't have bolts in both the top and bottom positions. Better still, don't ream at all but exercise extreme patience. Those spar sections have been carefully manufactured.