spar building...rivet spacer

[Gary Wallace]

any recommendation on rivet spacing while building the spars....have you guys used aircraft spruce rivet spacer or measure them and mark them by hand. I noticed the specs on the rivet spacer at aircraft spruce say max 1 inch spacing...dang close the the 1.06 or whatever..slips my mind..any recommendations here would be appreciated. thanks gary

[Chris In Milwaukee]

I plan to use a rivet fan/spacer. Measure out the bigger intervals, and then use the fan to fill in the rest. It's actually pretty easy if you drill right through the fan itself.

[mswain]

I bought the 20 hole fan before building my wings on the advice of another builder. I used it extensively while building the wings and spars. Its well worth the money. I measured mine tonight and the holes are 1 7/8" when fully extended.. The Spruce info is wrong.

[S Lathrop]

I took the time to draw out the spar in AutoCad.

I used a rivet spacing 1.0268 inches. That number will have all the critical locations line up exactly on the rivet holes. The plans give a spacing of 1.026 and by the time you get to the outer end, the rounding error adds up to a significant number. I made a drill fixture from a steel strip, 1/8 thick, 18 inches long and the width of the cap strips. The holes were 1/8". The drill fixture was narrowed on the ends to the width of the rear cap strip so I could use it for the rear spar as well.

I drilled all the cap strips and the spar web individually. I setup a drill press with so I had a table to support the parts as I drilled.

This may sound like a lot of work but once the tooling is made and drill press is setup the job really flies. I also did not have to do any more layout work because every thing is laid out on the rivet holes. That is the way the drawings are laid out as well.

Anything on the wing that had to be drilled more than once, I took the time to make a similar drill fixture.

I used a CNC mill to machine the drill fixture and all the plates that are riveted to the spar. I also made sure that the front and rear spar had the rivet holes lined up.

[Chewie]

I think the basis of the rivet spacing was Bob choosing the desired number of rivets he wanted between each rib so they would line up at each rib location, rather than measure with .0001 accuracy. Hence using a fan: only rib spacing and number of rivets are all you need to know. On the fan spacing, if it falls short you might be able to retract the fan a little and use every other hole.

[Gary Wallace]

thanks guys. i will purchase the 20 hole fan spacer from aircraft spruce....critical spacing will be measured to locate the holes per plans and fan will be used to space the 1 1/32 inch rivet spacing in between, good to know the fan has 1 7/8 spacing when expanded. thanks again. gary

[mswain]

Gary, you've got a good plan. Make sure the critical holes are located accurately and fill in the rest. Also, pay attention where the strut attach steel is....you don't want to put a rivet that interferes with that.

[Gary Wallace]

thanks mr swain..whats your first name? what stage are you on your project? I am cutting out all the spar plates...will finish tonight....then will deburr etc and get them nice and smooth. I will be bending the spars later this week or early next. I just picked all the spar materials up so im good to go there. that will keep me out of trouble for a bit.

[mswain]

thanks mr swain..whats your first name? what stage are you on your project? I am cutting out all the spar plates...will finish tonight....then will deburr etc and get them nice and smooth. I will be bending the spars later this week or early next. I just picked all the spar materials up so im good to go there. that will keep me out of trouble for a bit.

First name is Mike. I am pretty much done with my wings, at least for now. Been just about 3 years since I started. I am going to try to make my own wingtips starting sometime in the next week or so. I want to try my hand at composite work and I'd like to try and make some Hoerner Style vs. the rounded style that are available. Depending how the wingtip experiment goes I will hopefully be starting on the fuselage early 2016. I bought a basic fuselage from Mark/Bearhawk Acft. a couple of months ago....so I'll have a good head start.

[DRLPatrol]

Mike
I'm interested in making the Hoerner tips. Like the looks if nothing else. You are way ahead of me so I hope you keep us up to date with lots of info and pixs.

Doug