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Anti-Seize On Bolts For Cast Iron?

mcload

Hot Rolled
Joined
Nov 5, 2007
Location
Houston, Texas
As I'm assembling my second 9" Model A, I was just wondering if anyone has a preference on anti-seize compound
on steel machine screws into cast iron. I am familiar with the aluminum, copper coat, Permatex (aircraft), and thread lock stuff. (I've got it all).
Specifically for the saddle to apron screws, QCGB, and lead screw bearing at the tailstock end...those that get a bit more torque than usual.
Seems there should be something on the threads. Thanks for your opinion.

PMc

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Doing a lot of marine work I'm generally in the habit of using copper based anti seize of steel and cast iron. Which I tend to do on machine tool rebuilds as well.

Though in some cases if the threads of bolts and bolt hole were super clean on disassembly I might use atf or oil on assembly verse anti seize.

On occasion, I mix anti seize and oil as well. :D

Stainless steel use nickel based anti seize.

I remembered a thread in General about a year ago:
Anti-sieze compound types and uses

When looking for that, I also found this thread:
anti-seize compounds - [1] what is mechanism of action? & [2] uses in shop?
 
Great Info

Thanks Gunny; very helpful information. I appreciate the links. Sorry I didn't find these on my own.

I'm simply trying to avoid the issue that so many run into, that being removing seized machine screws
that hold on the QCGB, apron, and left lead-screw busing to the lathe bed. Clearly, someone else way down
the road will be doing this 7-10 years from now, not me. Perhaps they will thank me for a bit of anti-seize on
the threads. It seems to be the right thing to do. I'm going to use the copper type.
(If a non-critical bolt, I just coat the cleaned threads with oil.)

PMc



 
I use anti-seize on everything unless it is to have threadlocker. The best there was is the lead-based stuff - hard to come by now. Next best is copper and then for high-temps I use nickel.
 
The weakest grade of loctite makes a decent anti-seize for something that operates at normal room temperatures and isn't going to be disassembled for many years. Generally problems with such things are corrosion related, rather than mechanical seizing, due to unfriendly substances wicking in over the years. The expansion of loctite on hardening off provides an effective environmental seal all down the thread and under the head.

On undoing weak loctite shears at pretty low torque so it doesn't make disassembly significantly harder.

Clive
 
For something you do not plan on leaving in a field for a decade, I would go the blue loctite direction

threads stay clean and bonus of staying on the machine
 
Being in the marine field I use antiseize on everything i don't use thread locker on. Working on mostly aluminum boats I avoid nickel and copper based anti-seize. My go-to is a white ceramic based compound that is high temp rated and completely noncorrosive to all metals.Walter 53D854 Rock 'n Roll Ceramic Anti-Seize, Paste, 10.6oz Brushtop Can : Anti-Seize - $13.63 EMI Supply, Inc Also very popular around here although I don't use it is the green omc i/o unit grease that comes in a squeeze tube.

The saying is that any grease is better than no grease. Same for anti-seize.
 
The four big factors when considering anti-seize;

-Heat
-Moisture
-Time
-Galvanic potential

If it's a high temperature part like a bolt on the discharge side of a compressor head, absolutely anti-sneeze it.

If it will be outdoors or exposed to water, anti-sneeze it again.

If it's a part that will probably not get torn back apart again inside of 20-30 years, anti-sneeze it also since machine oils tend to dry out over that span of time if not renewed and will solidify into wax. Wax that will lock up threads, key stock, gears and pulley hubs on shafts and generally make life miserable.

Don't use anti-sneeze that has high galvanic potential with respect to the base metal it will be applied to. E.G. zinc and copper or copper and aluminum, lead & aluminum, etc.

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galvanic%20series%20noble%20metals.jpg
 








 
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