Thread: Hammer A3 31 Torx screw problem - won't come out

Are the Felder heads aluminum? That might justify it. Ours are all steel. The torque is also (Dr. Evil air quotes) "specified" by Byrd, but I reckon it's more of a guideline and have yet to see any adverse effects of an impact driver

Originally Posted by BobL

Once you get the wretched thing out, here's a neat tip I got from an old car mechanic but it only works on bare steel.
Before you replace the screws, remove any oil, penetrant etc and paint the threads with a concentrated CuSO4 solution and let it sit for at least 10 minutes. This will precipitate a layer of metallic copper onto any bare steel parts of the threads and makes it a lot easier to remove next time. I have sometimes cleaned the screws and dropped them into some conc CuSO4.

Or just a little dab of this LOCTITE C5-A Copper Anti-Seize - Loctite

Originally Posted by NCArcher

Or just a little dab of this LOCTITE C5-A Copper Anti-Seize - Loctite

Yep even easier to apply, especially for small stuff.

For scrooges who just need to do this on a very occasional basis they might already have some raw CuSO4 amongst their gardening chemicals.
I still have half a kg of the stuff left over from purchases in the 1980 to use as an inhibitor against roots getting into our sewage system. It didn't work.

Originally Posted by BobL

Once you get the wretched thing out, here's a neat tip I got from an old car mechanic but it only works on bare steel.
Before you replace the screws, remove any oil, penetrant etc and paint the threads with a concentrated CuSO4 solution and let it sit for at least 10 minutes. This will precipitate a layer of metallic copper onto any bare steel parts of the threads and makes it a lot easier to remove next time. I have sometimes cleaned the screws and dropped them into some conc CuSO4.

Reminds me of this stuff that we used when I was a young bloke.....

Molyslip

General assembly compound, and works great on threads.

Based on some of the experiences I've had over the years use of one of these anti-seize products should be mandatory any time you're inserting a steel fastener into aluminium.

Stainless on stainless even more so. That can bind and be impossible to remove. Working in the mines, anti-seize is mandatory on all threaded joints. Bloody good thing too. I've gotten into the habit and now use it at home all the time.
Brett, I've got a set of torxs keys/wrenches/whatever you want to call them if you need them.

If any lubricant is applied to the thread then the specified torque settings will be exceeded. This applies to any fastener as the torque figure as stated relies on a dry clean and undamaged thread on both the fastener and the nut or whatever the fastener is screwed into.

Originally Posted by NCArcher

Stainless on stainless even more so. That can bind and be impossible to remove.

Reminds me of student doing a project that involved first setting up and modifying a commercial 9m diameter Al receiving dish at the Uni. Once modified and tested the dish was to be dismantled and moved 1000 km to a remote location and set up again. The student was a bit bull at a gate but very entrepreneurial as well as being a qualified electrical fitter with 10 years experience on iron ore trains. He sourced the dish from China and saving $9k on the purchase but when he assembled it he made the mistake of not using anti seize on the SS nuts and bolts. (There were something like 3000 bolts in the whole thing.) Luckily he picked up on this fairly early in the job after he had fixed only a couple of hundred of the bolts and had to end up cutting most of these off and some were in very awkward places which required cutting into the Al frame and re-patching these. Fortunately he was also a gun Al welder.

Just in after being out all day, so I'll be brief. I have Chris Parks torque wrench which he very kindly brought over to fletty's today, so that's good for checking a) my Aldi $30 tq wrench (unused) and b) what's what with the clutch settings. I also have a tx bit from Chris which is a Wera so good Cherman quality. Am about to go down and have a superquick go, and then prepare for finishing the job at fletty's tomorrow.

The A3 31 is a steel head.

Nope. It just gave me a one finger salute.

I never use Copper based anti seize compound on a steel thread going into aluminium. I only use a Nickel based anti seize.
This comes from advice provided by spark plug manufacturers and vehicle manufacturers. The reaction between the copper, aluminium and steel can lock the screws in the aluminium. I’ve seen spark plug threads in cyl heads torn out when undoing spark plugs that have had copper based anti seize used on them.

Originally Posted by FenceFurniture

Nope. It just gave me a one finger salute.

Did it break the bit?

Originally Posted by BobL

Did it break the bit?

No - it was Chris' Wera bit and I didn't give any more than the others, but remembering of course that the suttons have the hollow middle which makes them (a little too easily) sacrificial. The Wera was a tighter fit too.

Break the insert!