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View Full Version : Aimpoint Micro & Hubris - A Stripped Screw Tale



Toonces
04-08-2020, 10:36 PM
So I've been screwing around with guns & reloading for 32 years, with a 20 year career as a metallurgical/quality engineer, without ever screwing up a fastener as bad as I did this week. I've successfully turned a lot of screws on various (sometimes pricey) firearms, and generally thought I wasn't too bad at not screwing things up. Then I tried to remove the mounting screws that held an Aimpoint R-1 to a DD mount. One came out with the 2mm allen wrench. One came out with the 2mm allen wrench later, of it's own volition. One came out with a T8 (see the problem) after the application of heat from a production soldering iron set to 800F. The forth screw has made me question my intelligence, as it has bested me at every turn.

I have used various combinations of the proper 2mm allen key, a T8 Torx, a T9 Torx with a sharpened edge tapped into place, a T10 Torx with a sharpened edge tapped into place, and a Brownells Magna-Tip bit ground into the shape of an easyout with a sharp edge tapped into place, in conjunction with heat supplied by a production (professional grade) soldering iron and a butane pencil torch, and lack of heat supplied by freezing. At times I have placed (at least) an estimated 30 in-lbs (measured against the tool used to calibrate torque wrenches/screwdrivers) of torque on this damn fastener, without it budging (WTF, I couldn't be so stupid as to use red Loctite, could I?). It is now stripped out to a diameter of about 0.120", because I thought it was moving and kept going with the improvised easyout. I'm now on about plan E, I thought I'd ask the hive mind for help. (@Wayne Dobbs) (anybody else with an educated guess)

If Wayne or someone else from the hive doesn't offer up a solution better than my own such as the address of where to $end it to fix my mistake, my next step is to secure the assembly in a vice and use a left-handed drill bit the size of the screw head, in conjunction with a lot of feed pressure, turned by hand, to drive the bit into the remainder of the screw head until it catches and turns the screw out. If that fails, drill off the head to free the mount, then use a torch and a heat shield to overcome the remaining Blue Loctite and a left handed 3/64" (0.047") bit in a Bridgeport to drill out the center of the remaining screw. A plan with some risk...

Up until this point, nothing has been damaged besides my pride and the screws. What next?

Thanks in advance,

Toonces

51547

WDR
04-08-2020, 11:36 PM
I'm surprised that much application of heat + torque didn't bust that thing loose. I don't have any suggestions beyond what you've outlined... beyond maybe somehow adding some vibration/impact with the screw under tension (if possible). Not optimal... but the mount is cheaper than the sight... if you were willing to sacrifice it to get at the screw sticking up proud of the sight body.

Aimpoint was helpful when I had an issue with the rheostat knob on my Micro (dead settings on the knob), but it did take a while to get it back. I think they ship them back to Sweden in batches... and the same for the return trip.

Good luck!

Wayne Dobbs
04-09-2020, 10:45 AM
PM sent.

Toonces
04-10-2020, 06:33 PM
PM sent.

I never received the PM. I suspect its because the Mods here are crap...

On a serious note, I sent you a PM. If you didn't get it, I know the Mods are crap.