Seized Stainless pin in alloy - tips for removal please

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MGambling

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I am changing standing rigging and am trying to remove the old for pattern.I am having trouble in removing the pin which goes through the spreader and its housing (Z spars mast ). I have tried heat and WD 40 to no avail. Anyone have any alternatives please.
 
Alloy will have corroded onto Pin, making it bigger inside than hole. Similar to steel Head studs in alloy head I had, my car, years ago. Vinegar & Plus gas applied regularly over days eventually allowed removal.
 
ACF-50. It changes the products of corrossion, I've used this on some seriously seized/corroded Al parts. Its very thin and penetrates so well it can loosten rivets by removing small ammounts of corossion.
 
Last year I had to remove some stainless pins which were stuck in an alloy casting at the top of the mast. Tried repeated immersion in boiling water, PlusGas, large hammer. I think in the end it was the heat and lump hammer (repeated) which loosened them - the snag was that some got their ends flattened by the hammer. I hope you find a better way!
 
None of the solutions offered so far really work - the corrosion products at the join ally/stainless occupy more space than the original ally so the fit of the stainless pin gets ever tighter. And the corrosion products arent soluble and dont react with acetic acid.

Much the best solution is heat cos the ally expands more than the stainless and the fit gets slacker. If it hasnt worked so far, you havent got it hot enough. Shocking the pin with a hammer whilst hot will help break the seal.
 
WD 40 is counter productive as you need to dissolve the corrosion products, which can be done with repeated application of boiling water. The problem is that WD 40 does not dissolve the corrosion, but appears to penetrate far enough to act as a barrier to the subsequent application of hot water. Heating with a blowlamp accompanied by hammering the pin whilst supporting the alloy part from behind is probably now the best bet. If the alloy part is hollow be very careful not to crush it.
 
I have had good results with Plus Gas when I had to dismantle a secondhand Lofrans windlass that I bought cheap. WD40 is no use for this purpose.

If you can accurately centre-pop the end of the pin you might find it easier to drill it out using a sharp drill.

When you come to re-assemble it, apply Duralac paste to the pin.
 
It will take a bit of everything, tapping, wd40, plus gas but especially heat, hot water not good enough, need a blow torch at least, one of those with a small gas canister as fuel is good, patience otherwise you will break something, 50 years of experience messing with stupid bits of metal helps!!
Stu
 
I second the suggestion by Tigawave; ACF50. amazingly effective on this kind of problem, and many others. Not cheap, but a little goes a long way!
 
lightweight hammer with repeated blows, not too hard to damage pin ends, important I think to support the alloy with a heavy object so that the shock of the hammer blows actually jars the corroded joint between stainless and aluminium, Out of interest, I have to ask why are you removing the spreaders from the mast? Also ALDI have just had a nice little gas soldering kit in which can be used as a miniture blow torch, pretty cheap, good luck
 
Have you tried or looked into what ACF-50 does?
I've used it many times and the difference from a penetrant or lubricant is significant. It is a very different approach.
It does axactly waht it says on the tin.

It does dissolve the corrossion deposits and seperates them from the metal surface.

ACF-50 actively penetrates through the corrosion deposits to the base of the cell where it emulsifies and encapsulates the electrolyte, lifting it away from the metal surface. ACF-50 then dispels this moisture and provides an atmospheric barrier which prevents any further moisture contact, thereby keeping the cell inactive. This compound continues to actively penetrate and "creep" into the tightest of seams, lap joints, micro cracks and around rivet heads, dissipating the moisture, even salt water, in these corrosion prone areas. These unique abilities of ACF-50 remain effective for 12 months, gradually disappearing as it is chemically consumed.

Its obvious that many people are not aware of developments in this area of technology. It as huge leap forwards from plusgas,wd,hammer,3 in1, and a blow torch.
 
This is why it's hard work introducing new technologies!
It will take some time for the WD/hammer school to move on I fear.

Could these be the same people still using rubber as a bearing material?
 
Heat usually works, failing that use acid - usually acetic but any of the inorganic acids, diluted, will work. You really need to soak it for 24 hours.

If it's really solid, and the acid radical can't get in to react with the AlOH, you'll have to drill it out, a very tricky task!!

I'd suggest getting onto Marilyn at Z-Spars UK or Loic Gilbert at Perigny and asking them what is the most likely piece.

Next time use one of the barium-based joining compounds, why UK boatbuilders never use them I don't know - they've been around in the aero-industry for about 40 years.
 
yawn yawn, rubber and water as a lubricant, nothing wrong with that, but at the end of the day experience always wins.
PS very professional looking websites, if the product you describe is as good as these it must be something really spectacular!
PSS
Loosen
Function: verb
Inflected Form(s): loos·ened; loos·en·ing \ˈlüs-niŋ, ˈlü-sən-iŋ\
Date: 14th century
transitive verb
1 : to release from restraint
2 : to make looser <loosened his tie> <loosen a screw>
3 : to relieve (the bowels) of constipation
4 : to cause or permit to become less strict —often used with up<loosened the rules>
intransitive verb
: to become loose or looser
 
If one hits a pin with a hammer it makes the pin shorter and fatter/tighter. This is also known as riveting! If on the other hand the pin is pulled out the pin will stretch and therefore will become thinner/looser. There are a few ways to achieve this, one is to drill and tap the pin then us a slide hammer. The other is to drill a deep hole and using a pin punch, in the bottom of the drilled hole, hammer it out. Drilling needs a bit of thought and skill, the drill must be square and in line with the pin, it must be in the middle of the pin. If you break the drill bit you will have more problems than you started with!
The best way to heat is a hot air gun. Diesel is very good cheap penetrating oil or It was cheap till the 1st of November!
 
I think a lot of people have missed the point, tap, hit, heat etc. it is a combination of everything that finally gets it loose
Stu
 
I learnt a new one recently - go to the supermarket and buy the strongest drain unblocking liquid you can find then bath it a few times and hey presto - believe me it works!
 
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