Main Spar

[Greg Pixley]

I completed the spar rivet process this weekend using the Panther tool. Took three easy days. I learned the following:
1. To press straight rivet heads, holding a square against the spare to ensure vertical seemed to give me consistent results. I pressed several hundred rivets before learning this! The rivet tool does not hold the spare vertical, especially when you move to the thinner sections.
2. The majority of my holes were reamed to .1885. On one spar I had some holes I drilled with #10 and in the thicker sections, the rivets expanded in the hole and didn't leave much rivet left for a rivet head. On the smaller holes (.1885) I was left with a big rivet head so even if it drifted off center some, I was left with a (maybe false) sense of security.
3. The -10 rivets required a larger reamer (.189) for some reason.
4. For the rivets in the mid section of the wing root, I did one wing with the Panther tool and did not get great results so I did the second wing on the floor with a C-frame and hammer. Then I ran it through the Panther tool tool to finish the squeeze. When you raise the tool up you get some flex.
5. When using a C-frame, push down on the spare and don't let it bounce off the rivet!

Thanks SPA for the support!

Keep Calm and Rivet On!
Pix

[Sacpilot]

Great reminders. Thanks Paul!

[psalter]

FYI, there are around 30 countersunk 3/16 rivets towards the root (where the 2 spars slide next to each other in the fuselage spar box). As Dan said, they are pretty easy to build, it took me about 3.5 days total. 2 days drilling/deburring, and 1.5 days to set the rivets with the squeezer. The spars come bolted together with temporary bolts/screws. Hard part is remembering how they fit back together after deburring We have pictures in the builders manual, but it doesn't hurt to mark them and take pictures before disassembling.

[Sacpilot]

Thanks Dan!

[danweseman]

Christopher
you can use any method you are comfortable with to set the 3/16 ad rivets. Many squeezers and yokes are not stiff enough to set these Rivets even though they may be technically with the squeezers specs .You will just need to do a few and see. Most builders do not have one ,and don't want to buy one (that's why they are building a pop rivet airplane...) SO we made the tool available. The pre built spar upgrade is in addition to the kit price. The upgrade includes the hardware (screws, bolts, rivets etc.) the spars (and fuel tanks) are pretty easy to build and we loan the tool out to make it easy.Any builder can do them, some just don't want to for many reasons!

[Sacpilot]

Hi Paul,

Yep. I saw that you can borrow. I was just wondering if we need it all if we have a standard pneumatic squeezer with a 3 inch yoke and the right size button head dies.

Also what is the cost difference between the Spar completed at SPA, and the parts necessary. If it was only a couple hundred bucks I think I would just have SPA build it.

Thanks.

[psalter]

Christopher,

We loan out the rivet squeezer you saw in the video for just the cost of shipping, you dont have to buy anything.

Paul

[Sacpilot]

Was watching the video on Youtube where Dan W. demonstrates the hydraulic pump in setting the rivets on the spar. This will likely show my naivety, but at first, I was going to pay for the finished spar. Then I watched and wondered why I would pay the premium. Not that hard. Then I thought, why would I have to borrow the hydraulic pump, if I have a pneumatic squeezer with a 3 inch yoke, or potentially a bigger yoke if a 3 inch won't fit. Although, supposedly larger yokes can twist which may be a problem. Can't it be used with a button head die to set these rivets? The holes aren't countersunk as it is a protruding -6 solid. So, it would simply be squeezing them. Am I oversimplifying things?

Also, what is the difference in cost for completed spar over just the spar parts themselves? I assume the stated cost replaces the cost of the unfinished parts so there is labor figured in there, or is that stated cost in store the labor on top of the parts?