Use of heat in releasing machine screw

penberth3 said:
Agreed. Softening flexible hoses that are a tight fit - yes. Seized fasteners - no, never.
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The main reason the boiling water trick fails is not using anywhere near enough

I've had seized fasteenings that have taken 7 or 8 or more full kettles of boiling water drenched and dribled over before they've released. Even used bluetack to make a funnel like damn to hold the water in place over the fastener when it was in an awkward place.

But sure, why not try flame heat and drilling out first 🤔

All I'm saying its an easy, cheap, no consequence if it doesn't help . Kinda solution...

I mean, don't get too hung up on it man...
 
On that Twister the machine screws were 5/16" (8mm) & about 3" long, they were just tapped into the grp filler so no metal plate as far as i could tell.
So you might just have to cut them off & redrill between the old cut off stubs. If you are using a grinder to cut the bolts or the track cover surrounding grp & windows with masking or duct tape to protect them from the sparks which will burn their way into the glass instantly.
When putting new bolts in best way is to dip the bolt threads in PVA release agent & let dry.
Drill hole oversize & blow out, fill with epoxy silica & microfibres runny enough to pour in. Paint the threads with some of the mix & pop in the hole.
As soon as its cured undo the bolt or machine screw. Mastic up & install your shiny new track with the shiny new bolts!
 
zoidberg said:
Should the above methods fail, might you consider using a bi-metal hole saw to drill around the heads of the machine screws, then lifting the 'destroyed' track away? With the m'screw heads exposed it should be somewhat easier to apply 'encouragement' to remove them.

You'll want some new track, of course, but that's not hugely expensive - especially if you ask in here and other boaty online sites.
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I like this idea and have stored it in my ‘fix bank’. Nice one Zoidberg! If traveller track is old and unobtainium you could easily have the drilled holes welded up and re-drilled too.
 
PabloPicasso said:
The main reason the boiling water trick fails is not using anywhere near enough

I've had seized fasteenings that have taken 7 or 8 or more full kettles of boiling water drenched and dribled over before they've released....
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Exactly, getting "enough" isn't possible, and you're getting less than 100C anyway, much less. A waste of time.
 
I've tried getting SS screws and bolts out of aluminium fittings many times over the years and have aways failed.
I've always found it very hard to dill out the center of a bolt or SS self tapping screws. The bit always seems to veer off the centre line and make mess of things.
Now I don't try and save the fitting. I use a diamond tipped masonry drill. The type that drill through granite, they take the form of a tube with small industrial diamonds brazed on to the tip of the drill.
Something like these:
Diamond Drill Bit 5.5mm
With these you can drill the head off the screw or bolt, without damaging the shank.
The fitting can the be lifted off, leaving a long shank to work on. A small propane torch and mole grips (hand vice) is then usually successful in extracting the rest of the screw or bolt.
 
Keith 66 said:
On that Twister the machine screws were 5/16" (8mm) & about 3" long, they were just tapped into the grp filler so no metal plate as far as i could tell.
So you might just have to cut them off & redrill between the old cut off stubs. If you are using a grinder to cut the bolts or the track cover surrounding grp & windows with masking or duct tape to protect them from the sparks which will burn their way into the glass instantly.
When putting new bolts in best way is to dip the bolt threads in PVA release agent & let dry.
Drill hole oversize & blow out, fill with epoxy silica & microfibres runny enough to pour in. Paint the threads with some of the mix & pop in the hole.
As soon as its cured undo the bolt or machine screw. Mastic up & install your shiny new track with the shiny new bolts!
Click to expand...
This sounds like my sort of solution! - very 70/80s to just tap in to fibre glass - Twister - Kim Holman design (love the story about Kim Holman and Rabbi Lionel Blum).
 
Ian_Edwards said:
I've tried getting SS screws and bolts out of aluminium fittings many times over the years and have aways failed.
I've always found it very hard to dill out the center of a bolt or SS self tapping screws. The bit always seems to veer off the centre line and make mess of things.
Now I don't try and save the fitting. I use a diamond tipped masonry drill. The type that drill through granite, they take the form of a tube with small industrial diamonds brazed on to the tip of the drill.
Something like these:
Diamond Drill Bit 5.5mm
With these you can drill the head off the screw or bolt, without damaging the shank.
The fitting can the be lifted off, leaving a long shank to work on. A small propane torch and mole grips (hand vice) is then usually successful in extracting the rest of the screw or bolt.
Click to expand...
One question - if one drills/grinds off the head is there a thread in the aluminium track (IYE) or will it just lift off?
 
I had been really struggling to get 10mm countersunk stainless machine screws out of the alloy baseplate to which a large Lewmar winch was attached. I had tried all of the above without success.
It’s a slightly different situation as the screw doesn’t go through GRP before entering the alloy.
Finally succeeded thanks to a welder. He Tig welded 10mm hex head machine screws to the heads of the stuck ones and then very quickly, after each was welded, put on a socket with a T-Bar and managed to unscrew them. (First try was with a one sided socket wrench which didn’t work).
There was an acetal sheet between the winch and the alloy and that suffered some heat damage plus the original machine screws were obviously a write off, but otherwise there was no visible damage.
 
"One question - if one drills/grinds off the head is there a thread in the aluminium track (IYE) or will it just lift off?"
Not that I've ever seen.
If the fitting was tapped, and the fastening going into a tapped embedded aluminium plate, you'd never be able to tension the set screw or get the bolt through the fitting.
A bolt has a plain shank, and you need a cleance hole to get it through. A set screw is threaded all the way up to the head. You'd have to screw it through the fitting and then when it engage in the plate there would be fixed gap.
There could be and probably will be corrosion the bolt or set screw and the track, especially if the hole wasn't anodised, and that will probably more difficult to move if a set screw has been used.
It can be an intractable problem, almost impossible to remove the track without the complete destruction of the track.
Whoever installed it didn't consider its removal. A little bit of Duralac or even copper grease on the treads, would have made the job easy.
 
Boiling water has certainly worked on seized stainless and aluminium on more than one occasion for me - but, as @PabloPicasso says, you should use kettles and kettles full of it (and also penetrating oil), and not everyone has the time.

I'm not sure whether boiling water will work for this application because the nut is described as being imbedded in the GRP, below the deck surface and presumably insulated from the water being poured on.
 
In old times, to heat a sized screw they red hot heated a piece of steel or better copper on the forge and pressed and kept it for a while upon the screw head.
This does not affect the surroundings as a flame does.
 
What has worked for me a few times is a hot air gun and release fluid of some sort. Warm the assembly with the hot air gun, it doesn't need to be really hot, then squirt on the fluid. Do this maybe 10 times. The alternate heating and cooling gives a bit of thermal shock and the cooling cycle also draws the fluid into the joint. Needs a lot of care and patience but has worked for me. Having said that I once had to take an aluminium alloy stanchion base home to remove a siezed stainless bolt the section that was sie wasn't even threaded. I made up a tool so it could be pressed out. It took an enormous load. Rather than drilling heads off it's much easier to deliberately shear off the heads using a suitable well fitting tool but you have to make the first attempt pay. If it doesn't work you've still got the drill option.
 
KAM said:
… it doesn't need to be really hot, then squirt on the fluid. Do this maybe 10 times. The alternate heating and cooling gives a bit of thermal shock and the cooling cycle also draws the fluid into the joint. Needs … patience
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I'm sure this is why boiling water works too. I was surprised by how well it works and equally by the claims in this thread that it does't!
 
If (!) the boat in question didn’t have a grp moulded headliner, which I believe these Sadlers do, then I would Dremel off the grp from underneath to expose the aluminium plate. From then on its ‘just’ a messy matter of holesawing each threaded bolt hole to release the threaded bolt ends and remove the track intact.
Even then I would expect there to be some effort and corrosion to deal with on the shanks of the bolts and the oxidised under face of the track which has probably been sitting in salty damp its entire life..
Don’t envy the OP and he hasn’t said why he wishes to remove the bolts..
Best of luck
I’ve taken a few Genoa tracks over the years off but always had access underneath.
 
I had another look the other day and on the port side from inside the cockpit locker I can just about get a finger in the gap below where the track sits and there is some very rough glass. The level of crudity reminds me of lasers, where the mast socket in the deck moulding is “secured” by a dollop of resin dropped in the hull moulding and then hull and deck glued together. I have no intention of removing the massive panel over the quarter berth as it would involve removing a lot of wiring fixed over it.
Basically if the plates cannot be tapped into from above then new track is just going to be glassed in. It’s not just the cutting of large pieces out of the boat but the almost impossible job of reinstating.
Maybe 30 something with boundless enthusiasm would go for it but not me.
 
eddystone said:
I had another look the other day and on the port side from inside the cockpit locker I can just about get a finger in the gap below where the track sits and there is some very rough glass. The level of crudity reminds me of lasers, where the mast socket in the deck moulding is “secured” by a dollop of resin dropped in the hull moulding and then hull and deck glued together. I have no intention of removing the massive panel over the quarter berth as it would involve removing a lot of wiring fixed over it.
Basically if the plates cannot be tapped into from above then new track is just going to be glassed in. It’s not just the cutting of large pieces out of the boat but the almost impossible job of reinstating.
Maybe 30 something with boundless enthusiasm would go for it but not me.
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I don’t flex like I used to either..

Is there specific information on the Sadler owners association from someone who has photographed this job perhaps?
 
One thing worth remembering, If you try tapping plates in fibreglass the tap will go blunt very very quickly & then jam & snap off. I know this from personal experience, That boat still has the broken off tap in it there was no way it was ever coming out.
Epoxy cast threads are quick easy & strong.
 
eddystone said:
Seeking some advice on usefulness of heat to help release machine screws attaching main sheet traveller track to bridge deck on Sadler 32. I’m assuming that the screws are threaded into aluminium plate embedded in lay up. This seems to be standard Sadler practice. After over 35 years of galvanic action between the aluminium plate and s/s screw assuming well corroded in. Not helped by slotted head on screw.
So far used ATF/acetone mix, Plus Gas and cold shock spray. My feeling is that heat wouldn’t penetrate as far as the aluminium plate so unlikely to create differential expansion between s/s and aluminium.
Correct assumption?
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Had the same problem on a 40 yr old set up. Only solution was an impact hammer you hit , about 3 hrs and a very tired arm. Was best part of 45 mins before I got any turn at all, but at least with this system you shouldn’t be damaging the screw head
 
howardclark said:
Had the same problem on a 40 yr old set up. Only solution was an impact hammer you hit , about 3 hrs and a very tired arm. Was best part of 45 mins before I got any turn at all, but at least with this system you shouldn’t be damaging the screw head
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Powered Impact drivers are popular for a reason these days. Make sure you use tool heads designed for impact drivers if you go that route.

Can thw OP get to the bolt heads? Are they slots, x's, hex allen?
 
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