Removing Stuck screws

[RickH]

I have an expensive Marine item that is manufactured from Billet Aluminum.
It is assembled with 316 stainless steel csk hex head screws.

I need to disassemble and the screws are stuck fast. (aprox 9 months old)


The heads are 7/32" hex imperials (yep 100% sure - It's a US manufactured product)

I have tried encouraging Allen key with mallet - no good.
Applied releasing oil - no good (happy to try a specific product if there is a particularly good one)

So far only one of the 8 have come out !


Now one way to approach this would be to use an impact driver ... I have a compressed air 1/2" square drive impact driver, and assorted sockets ... but would need a 7/32" hex insert ............ anybody know where I can get one ?

 

[JohnD]

try heat

you know that stainless screws are prone to seize, and you should assemble using a Stainless Screw Anti-seize spray?

 

[RickH]

Not come across stainless steel anti seize spray .. any name/make you can give ... I'll see if I can find some.

 

[JohnD]

I got mine from the company I order my stainless bits from... used to be Mr. Fast'ner, now part of MPS I think. Can't see it on their website now.

It is grey spray or paste, not the usual Copaslip stuff. Copper in this situation will cause seizing.

It lasts a long time, I thought it was quite common.

Loctite make a version, I think you would have to try an engineering supplier or a stainless nut and bolt dealer.

 

[mulberry]

Consider using an freeze product, the thermal shock should do the trick. Its available in areosol form.

 

[RickH]

Consider using an freeze product, the thermal shock should do the trick. Its available in aerosol form.

Tried Hex Allen key ... no good

Tried hex bit in ratchet spanner .. no good

Tried above after soaking in Plus Gas .. no good

Tried above + heat .... one came out.

The final solution was to take a TORX T40 bit and hammer that in until it bottomed ... this swaged itself into a multi-point fix ... they each came out this way.

It did take a ratchet socket spanner and a 3' bar .... one hell of a crack each time .... but all came out clean.

First bit was a freebie in a multi 1/4" set ... totally ruined after removing one screw.
Then I bought some WERA bits ... one bit removed all others and looked as good as new when finished ... WERA bits really are much better than any others.

Have now found some Stainless Steel anti-seize paste ... so will use that when I reassembly ... after parts come back from being Anodized.