Drilling F-633 control column mount to center section bulkhead?

[txnbuilder]

Tonight I started drilling the F-633 control column mounts. Drawing 11 shows a 3/16" hole on one end of the F-633, and then another 3/16" hole match-drilled with the center section once the mounts have been squared and aligned in place.

My problem is that the pre-drilled hole in the center section (F-704B) is quite a bit larger than 3/16" -- I measure something like 0.22" -- probably the right size for those large pre-set rivets in the center section. By the way, all of the other holes in the aft center section (where the seat ribs bolt with AN3 bolts) are also this larger size.

This means those two bolts are going to be working almost exclusively in tension.

Is this normal? After a search here, I did not see anybody else talking about this, so should I just do my best to align the mount at 90 degrees to the center section flange and drill the 'other' 3/16" hole through the larger pre-drilled hole in the center section?

Thanks!

Luis

 

[rzbill]

Make sure you are in the right place

See drawing #11
The view titled "AFT CENTER SECTION BULKHEAD ASSEMBLY REAR VIEW"

You will note a callout to "drill 1/4" for spacer bolt" for a hole that is 2 spaces away from the proper position of the F-633. Check your F-633 position.

The factory hole diameter is not defined on the drawing but could easily be 0.22 for that spacer bolt operation. I don't remember the original size since this was 3+ years ago for me.

If this does not resolve the issue, a call to Van's may be in order.

 

[txnbuilder]

Holes are actually the wrong size...

After a brief chat with Vans Support, it turns out the holes were drilled to the wrong size.

The fix is simply to drill them out to 1/4" and use AN4 hardware. I have the same problem with all of the other bolt holes for the seat ribs, so those will get drilled to 1/4" as well.

Vans is sending the hardware in the mail, so all is good again

One lesson learned from this is that in general, the design of these things is REALLY well thought out -- if something seems sloppy (like using an oversize hole and loading the bolt in tension for no apparent reason), it's well worth a call to Vans.

Luis