7a QB Step Installation

[tx_jayhawk]

I'm installing the steps in a 7A QB, and I was looking for some helpful tips. How have people been drilling the 1.5 inch hole on the inner rib? The SB 7A has you drill it prior to installing, as you can't get an angle drill in there after its installed in the QB. I don't see how a dremel can get in there real well either.

Also, any tips on bending the flange? I plan to cut/round the corner, but it appears the whole assembly needs shaped somewhat.

Thanks for any help. There is one similar post on this, but the method described was not clear to me.

Scott
7A Fuse

 

[robertahegy]

I used a long pilot bit to drill straight through for alignment purposes, then a hole saw on the outer hole and hole saw with angle drill for the inner hole. I used a Dremmel with sanding drums to shape the inner angled hole for the shape of the tube going through. A Dremmel with 1/2" coarse sanding drums works well for shaping holes and other AL parts.

Roberta


Photo showing outer hole finished, pilot hole in inner rib. I was shaping a stiffener with the dremmel. There is plenty of room for an angle drill.

 

[Derrell]

I think I used a Drill bit Extension from HD & a hole saw. It's been a while.
To form the flange, I chucked the step in a vise & used a crescent wrench to get the right radius. Trial & error & use small increments. To do again, I might consider flush rivets. I've seen at least one RV with the flange on the inside. Don't ask me how.
Derrell
7A Finish

 

[Radomir]

the flange was really easy to bend, which I was surprised with.. I thought you'd have to put serious muscle into it.. As Derrell says, just put it in a vice and bend little by little.. Definitely have to check it often.. but it goes easy..

I didn't have to cut the corner (except to round it a bit) and it fit like this:

HTH

 

[tx_jayhawk]

Which Angle Drill?

Thanks all for the replies. Roberta, your angle drill must be much thinner than mine, as mine definitely won't fit with the big hole saw bit on it. What type did you use?

 

[robertahegy]

I have a little Milwaukee offset drill with a short arbor holesaw. Using an extension, as someone mentioned, should also work OK. Use a long pilot bit and just carefully start the hole (you will have to just get one edge going) and slowly grind your way through.

Happy building, and happier flying,

Roberta

 

[vlittle]

Bending step flange

A good way to bend the step flange is to use a Crescent wrench (adjustable spanner). Just set it to clamp lightly down on the flange and bend.

Makes for quick work.

Vern Little -9A

 

[mark manda]

mine bent easily with a crescent but had it in the vise. Option--go without the bend.

courtesy of rhegy (IIRC) back when she was helping me.

 

[tx_jayhawk]

How Deep?

Sorry for the continues bandwidth waste, but how important is it that the step is flush? Given the weld fillet, it appears you need to make the hole notably bigger than the 1.5" to get it flush at the bottom. I've enlarged the hole slightly, but I'm hesitant to go any more. What have others done?

 

[mark manda]

your step looks good to me; looks close enough to pull the rivets. but i'm not an expert and not flying. I might hit that edge one more time with a dead blow, but that's just me.

You going with rivets or #6 C.S.?

looks good so far.

 

[Radomir]

I enlarged the hole until the steps were flush... you wont' see the gap anyways. just go slow, though.

 

[Squeak]

sit back ?? aft

Make sure you sit them aft as much as possible so the flap will have clearance. They should be sit back ?? aft of what the print shows.
Squeak
Flying 7A

 

[Rivethead]

The diameter of the hole means nothing your rivets are what hold the step in place. There is absolutely nothing gained by making the hole to small.