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Old Feb 10, 2016, 08:31 AM
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Question
machine screw removal?

I would like to get this machine screw out.
It's attaching two parts together that are cast aluminum.
I've put some heat to it and penetrating oil to no avail.
I would like to save the screw .
Ideas? more heat? drill it out?
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Old Feb 10, 2016, 09:49 AM
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you could try an overnight soak in a mild acid solution(vinegar)you most likely have some dissimilar metals crud in play..
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Old Feb 10, 2016, 10:41 AM
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Penetrating oil is very helpful, but I've found some work better than others. Which did you use, and how long has it been soaking? Repeated heat cycles are also helpful. When you are ready to try again, start with a cold assembly, then rapidly heat the outer aluminum. This will expand faster than the screw and possibly break the bond.
It doesn't look like a beefy assembly, so an impact driver may be out but a sharp rap on the head of the screw sometimes is enough.
Why save the screw?

Dave
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Old Feb 10, 2016, 10:52 AM
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I have had good luck by heating very hot with a propane torch, and then dropping into cold water. The shock cooling breaks up the corrosion holding the parts stuck tightly together.
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Old Feb 10, 2016, 11:08 AM
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Heat the Aluminum and hit with the set screw with penetrating oil. Or soak in diesel fuel overnight.
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Old Feb 10, 2016, 01:01 PM
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Soak it in some Aero Kroil.
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Old Feb 10, 2016, 01:36 PM
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Good ideas, Thanks.
Liquid wrench was the oil used.
Have some Corrosion X I could try as well.
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Old Feb 10, 2016, 02:10 PM
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This is what I use on my old, rusty bike rebuilds.... http://www.jlsmithco.com/lubricants/...ant-11oz-spray

Nasty stuff on your hands and hard to wash off, so use good rubber gloves.

And if you use heat to help loosen the screws, use it gingerly. Aluminum melts at 1,200 degrees F, and that's an easy temp to reach with propane and small parts.
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Old Feb 10, 2016, 02:45 PM
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Quote:
Originally Posted by Jerome Morris View Post
I would like to get this machine screw out.
It's attaching two parts together that are cast aluminum.
I've put some heat to it and penetrating oil to no avail.
I would like to save the screw .
Ideas? more heat? drill it out?
Soaking it with penetrating oil is the best option. it may take a while to loosen up.
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Old Feb 10, 2016, 02:50 PM
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All the above are good ideas. They hit all my favorite oils. Soak overnight.

Try turning the screw in the tightening direction to see if that breaks it free.

You can also carefully use a small punch and hammer at the edge of the screw to tap it in the loosening direction.

Make sure your screwdriver is the proper size. A undersized or dull or rounded screwdriver blade will quickly destroy the slot in the screw head.

Last resort is drilling. Often, a left-handed drill bit will catch and remove the screw without having to use an extractor.

Not sure heat will work well this time. The screw is probably not aluminum. So if the screw expands more than the aluminum when heated, it will just be tighter when hot. It's worth a try though.
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Old Feb 10, 2016, 05:46 PM
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I see all your typos
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+1 for Liquid Wrench. Works better at penetrating than WD-40 or anything else I've tried.

Also try tapping the area lightly with a non-marring hammer. Vibration helps break loose frozen parts.
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Old Feb 10, 2016, 05:50 PM
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I see all your typos
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Quote:
Originally Posted by ericbphoto View Post
Make sure your screwdriver is the proper size. A undersized or dull or rounded screwdriver blade will quickly destroy the slot in the screw head.
This.

Most people just grab a generic flat blade screwdriver and 'make it work' even though it mars the screw head if it's undersize. I have a set of hollow-ground screwdriver bits in all sorts of sizes that that I use when precision is needed.
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Old Feb 10, 2016, 07:34 PM
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Not to worry. I snapped the head off so will now drill her out.
Thanks for all the help.
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Old Feb 10, 2016, 08:53 PM
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Quote:
. I snapped the head off
Well that sure made the decision easy.
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Old Feb 10, 2016, 09:09 PM
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That was plan "B"...
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