4 mm EB tail gearbox mod - screw length?

[SeaHawk]

I have managed to strip the original 3mm screws that hold on the EB gearbox. I have tapped the holes out to 4mm and have the 4mm screws ready to be cut to proper length.
Do I cut the screws short enough that they do not touch the aluminum tube that sets the gear mesh or do I leave the just long enough to touch them?

[cbergen]

Ideally, they should not press on the inner tube. If they do, then they won't tighten properly to the BOOM. IOW they will bottom out on the tube, but they won't hold tight to the boom.

Now. If you are SURE of your gearmesh, then I have seen some that drilled and tapped INTO that inner tube as well..........Of course then you lose the ability to adjust your gearmesh.

[SeaHawk]

O.K. Chris...I have done as you recommend. (usually a good idea for me:))
In case anyone wants to know, I measured the depth of the hole, down to the gear mesh spacing tube to be just a hair under 4mm. I consequently cut the 4mm screws to 3.5mm. That's only a few threads. The fit good and tight and they don't hit the tube. I plan on heavily loctiting and maybe a little bit of JB Weld on at least one of the screw heads to prevent it backing out. I'm sure that's overkill, but it makes me feel better.

[flyingrhino]

I did as Chris suggested. I set the gear mesh then tightened the set screw on top to hold the inner tube in place. I then drilled and tapped the holes to 4 mm. I did this after a sudden tail drift in flight at which time I landed and noticed the gear box was loose in the tail boom.