Sonofa...

[ryguy76]

Just doing some final checks on my protos before the soon to come maiden flight, and noticed some vertical play in the main shaft that wasn't there when I built it. Perhaps the collar was never tight enough and the test spool up vibes loosened it. I unscrewed the set screw and and applied a more liberal amount of loctite. Problem is that now I've stripped it trying to get it in there nice and snug, but now I can't get it back out.

Any ideas?

Also, any tips on keeping this firmly in place so I don't re-introduce vertical play?

[ercapoccia]

If your collar is not tight enough on the shaft you can just sand a little the vertical gap.

[isogloss3d]

I've been able to occasionally remove small stripped grub screws with heat from a soldering iron and any tool that will fit in the hex and find purchase.

Items that have fit include the right sized flat-blade screwdriver, sometimes I have to find a sacraficial screw driver and grind it down to fit. Also sometimes a torq bit of similar size will fit well enough to work. Lastly I've used the correct size driver and shimmed the play with one or two small diameter wires.

Good luck.

[ryguy76]

Originally Posted by isogloss3d

I've been able to occasionally remove small stripped grub screws with heat from a soldering iron and any tool that will fit in the hex and find purchase.

Items that have fit include the right sized flat-blade screwdriver, sometimes I have to find a sacraficial screw driver and grind it down to fit. Also sometimes a torq bit of similar size will fit well enough to work. Lastly I've used the correct size driver and shimmed the play with one or two small diameter wires.

Good luck.

Good ideas... What about soldering a sacrificial bit o' steel rod into there and using vise grips to turn it out? tried that before?

[Soccerjay]

Originally Posted by ryguy76

Good ideas... What about soldering a sacrificial bit o' steel rod into there and using vise grips to turn it out? tried that before?

I think the heat is best, should make the loctite pliable enough to take the collar off and then the set screw will be kinda loose and any of the above methods to get it out.....sometimes a different bit will get a tad deeper in a "stripped" screw and get the bite to get it out

[isogloss3d]

Originally Posted by ryguy76

Good ideas... What about soldering a sacrificial bit o' steel rod into there and using vise grips to turn it out? tried that before?

I haven't tried that.

You could try that if all else fails but the tensile strength of a standard electrical solder joint is pretty low and would most likely break before the fastener breaks loose. A tack weld would work but not an easy task given the small size and location.

I just took a closer look at the collar and realized its not a set screw but a regular cap head screw.

You should just barely be able to get in with the a screw extractor. http://www.summitracing.com/parts/wmr-w80563/overview/ I've used the smallest one in the Craftsman (set of 3) on button and cap head 1.5mm screws in the past. Still use heat, push hard and go slow.

If you don't own screw extractors and don't plan on using them often, you might be better off just replacing the main shaft and collar.

[ryguy76]

I have tried a few things and can't get the bolt to budge. It's just too small. So... I was thinking I'd just order a new shaft and collar, but innyhe interim, this one is on there tight enough that I can't move it. I'm thinking that I should use it as is until I need to order another one. Should I loctite it in place or use something else to commit it to its current position? I don't fully trust that it's as tight as it needs to be, even though I can't move it.

I could JB weld it too.

Thoughts?

[isogloss3d]

Originally Posted by ryguy76

I have tried a few things and can't get the bolt to budge. It's just too small. So... I was thinking I'd just order a new shaft and collar, but innyhe interim, this one is on there tight enough that I can't move it. I'm thinking that I should use it as is until I need to order another one. Should I loctite it in place or use something else to commit it to its current position? I don't fully trust that it's as tight as it needs to be, even though I can't move it.

I could JB weld it too.

Thoughts?

How much vertical play are you talking about? If it's 1 mm you could probably fly it as is while you wait for new parts. If it's 1 cm then I certainly wouldn't want to fly that way, especially a maiden flight. If you've tightened the screw so much that it had stripped then the collar is probably plenty snug and doubtful to move again.

Better safe than sorry and a Protos crash can get expensive if you take out your main blades or a frame.

[ryguy76]

There's actually no play in it right now. It started to strip initially when I built it. (I must not have had my driver in there good enough as I have good tools and this was the only head I stripped in the build).

I noticed the play, (2-3mm) after some test spool ups, so I backed it off to re-apply loctite and start again, but ended up fully stripping it when I tightened it again. It's actually in the right place now with no play, but my fear is that it may only be as tight as I had initially got it during the build and it may slip eventually.

BUT... I figure that the collar and shaft are right-offs at this point anyway, I might as well just JB weld the collar in place, being that there is no play now and I can use it until I need to replace it.