Suggestions For Loosening Frozen Machine Screws?

Free Republic ^ | 12 March 2017 | Windy

[Windflier]

Cut inch off the long end of allen wrench, put in screw and several firm blows with a hammer.

I'm going to call the manufacturer in the morning to verify that the screws aren't left handed, then apply some better penetrating oil before proceeding. I like your idea.

[Lean-Right]

PB Blaster. Apply and
let it soak for a few
minutes.
You are encountering
a dissimilar metal
corrosion condition.
I have used this stuff on
very rusty hardware.

[GBA]

Fwiw, "Machinist Workshop magazine studied the most popular penetrating oils to see what did the best job of removing rusted bolts..."

[barmag25]

Left handed drill bits and plenty of knocker loose.

[Windflier]

Thanks for the excellent advise. I wouldn’t call myself a “wrench”, but I’ve turned a bolt or two in this life and know you speak sooth.

I’m going to first try some of the penetrating oils folks have suggested, then take it up a notch up if needed. Thanks.

[right way right]

Aerokroil and PB blaster are the two best I believe.
Propane torch to heat the block some may help. Aluminum dissapates heat badly and it does not melt slowly, it just collapses quickly if you overheat it.

[LesbianThespianGymnasticMidget]

Then it is just plain easy. Drill them out retap the threads and use a larger allen screw. If there is clearance use bolts. So much easier when they get seized.

[Windflier]

Tapping on the heads creates vibrations that pull the soaking fluid into the joints of the threads, don’t be in a hurry, work, then let sit, spray and repeat, leave over night if you can.

Thank you, Tet. That's just the sort of mechanic's advice I'm looking for.

[barmag25]

About my above post. Get a left handed drill bit. Get a small metal punch and grind a fine point and tap a small indention.

Use the left handed drill bit in a cordless drill. Drill counter clockwise.

Soak it for a few minutes beforehand in knocker loose.

[Freedom4US]

LOL!! Ballistol smells nasty.. it’s pukeworthy.

I saw this thread earlier tonite.. “Uh-oh... there will be a gazillion replies on this one..”

Kroil is available mail order only, not sold in stores.

Supposedly 50/50 ATF & Acetone works good. I never saw it do anything special but live in the rustbelt. Just about anything is better than WD40. It has its uses, this is not one of them.

[Gene Eric]

>> These screws are countersunk into an aluminum block

Cylindrical screw heads? You can notch the heads for a quality flat-head screw driver. Force down on the screw driver while using a wrench to rotate it. You can notch the screw head with a drill. Again, pre-apply a lubricant for a few hours.

Another idea... what about torx drive? It’ll probably spin but it’s worth a shot. A torx drive is gonna be harder than the screw and that might be enough to grab within the allen hole.

[Windflier]

penetrating oil (not WD-40, real penetrating oil)

That's the first thing I'm going to fix. I'll pick up one of the better penetrating oils that have been suggested on the thread tonight.

My machine has three sets of feed roller assemblies, so we can still use it in the field, then work on the one busted assembly during down time.

If The stuck screws still won't budge with muscle power or with tapping, I'll pick up an impact driver to tackle it.

Thanks for the advice.

[right way right]

Do these screws hold the block onto another one of steel or aluminum?

[semaj]

Warm them up with a torch, not to hot, just warm enough to expand a little bit, then cool them off with some diesel oil.

[Windflier]

Assuming you lost the hex hole...

No, the hex hole is just fine. I snapped off the business end of an Allen bit while trying to turn it with a socket wrench. A big enough chunk was sticking out, that I was able to yank it out with pliers.

I think my next step is obtaining a better grade of penetrating oil, and trying the tapping method that's been suggested.

Thanks for your help, Gene.

[Windflier]

Heat

Wish I could, but there are neoprene rollers and plastic bushings attached to the shaft, which is held in place by the aluminum block where the frozen screws are located.

It's a helpful tip, but won't work in this case.

[Rockingham]

Try pressing a piece of dry ice against the screws. It has to be handled carefully with gloves, but, colder than water ice and applied long enough, it may shrink the metal of the screws enough to make them looser.

[Windflier]

Also, an impact driver will work if there is room to use it.

Thanks for the suggestion. It's pretty tight where I'm working. If it comes to it, I'll have to see if I can find a right angle impact wrench.

Either that, or remove the entire roller assembly from the machine so I can get at it.

[Disambiguator]

Kroil is available mail order only, not sold in stores.

Well, that's not entirely true. I bought a pint of the liquid from a local gun shop, and a screw place nearby sells the aerosol.

[Windflier]

Auto parts will have a selection, maybe kroil, certainly PB Blaster

Excellent. I'll pick up either the Kroil or the PB Blaster tomorrow.