Seized bottle screws

[PabloPicasso]

Lift out is at the end of the week, and my galvanised cradle has two sized bottle screw. So far I've tried spraying with easing oil, brute force, heating with a low lamp after loads of easing oil sprayed on.

No joy

Anything else to try? Hints, tips greatfully

 

[billcole]

Which easing oil have you tried. I've always found Plus Gas to be streets ahead of the more widely used WD40

 

[RichardS]

How large are the nuts on the bottle screws, assuming that it's the locking nuts which are seized? I'm picturing a very large coarse thread which would be virtually impossible to strip so after applying easing oil and heat with a good blowlamp then a breaker bar or 1 metre length of scaffolding pipe must be the answer as I assume that you can't use a rattle gun.

Sometimes a little tweak in both directions can help.

Richard

 

[PabloPicasso]

No it's not the lock nut. It's the bottom end of one bottle screw. The lock nuts me bed with some gentle encouragement. In tap tap

The bottle screw had a hole to put a bar into but anything I've tried to use so far just bends when a scaffold Pope is used

 

[James_Calvert]

On the brute force lines...

What about gripping the barrel with a large pair of stillsons?

 

[ytd]

hitting the bottlescrew end with 2 hammers sometimes helps

 

[Skylark]

Mine is a 6 leg from Yacht Cradle Company. The bottle screws incorporate both a left and right hand thread rose joint for adjustment. A few years ago a couple of them seized. It took a fair amount of heat to free them off. I used a 2m long pipe through the rose joint eye while holding the body in a bench vice. Heat and brute force saved the day. I now completely remove, clean and regrease each one every year as routine maintenance.

 

[savageseadog]

Use a roofer's blow lamp, a big one in other words

 

[vyv_cox]

Are the bottlescrews galvanised steel or stainless? Steel ones will succumb to the heat and lubricant methods but if the stainless steel type have galled nothing will move them. Galling is effectively welding between the rotating parts.

 

[afterpegassus]

Heat them to cherry red or soak in a bucket of old diesel for a few days.

 

[PabloPicasso]

hitting the bottlescrew end with 2 hammers sometimes helps

Ok. I'll try that.

 

[PabloPicasso]

Heat them to cherry red or soak in a bucket of old diesel for a few days.

Ok I'll see if I can get a blow torch and heat them.

I doubt I'll be able to easily undo the nut/bolt at the bottom end to get the bottle screw so soaking in deisel is a likely non starter.

 

[PabloPicasso]

Ok so more brute force tapping the ends with a lump hammer plus more better easing oil. Heat to cherry red with a blow torch.

Bucket of deisel not a goer.

Any other ideas.

It's a galvanised steel type (not stainless steel on my cradle anyway??)

 

[penberth3]

Ok so more brute force tapping the ends with a lump hammer plus more better easing oil. Heat to cherry red with a blow torch.

Bucket of deisel not a goer.

Any other ideas.

It's a galvanised steel type (not stainless steel on my cradle anyway??)

If they're so bad you might want to get some new ones. It looks like you're going to spend a lot of time and effort on this and probably finish up with damaged screws anyway.

 

[DownWest]

Suspect that cherry heat would melt the zinc and make it worse. Angle grind the bottom bolt off and dunk it in diesel? Or just replace, due to the time limit?

 

[PabloPicasso]

Well I've sort of succeeded. Three of the four are rung smoothly now. The last one is free at the top and well sensed at the bottom.

 

[PowerSlapper]

Well I've sort of succeeded. Three of the four are rung smoothly now. The last one is free at the top and well sensed at the bottom.

Rather than using the usual freeing oils you could try a 50:50 mix of ATF and Acetone. This works when even PlusGas or the latest WD freeing oil fails.

 

[Leonidas]

Weld a 6 inch lug on the bottle and hammer away with a heavy mallet

 

[PabloPicasso]

Rather than using the usual freeing oils you could try a 50:50 mix of ATF and Acetone. This works when even PlusGas or the latest WD freeing oil fails.

I was using a brake fluid/acetone mix. Is that what you meant by ATF?

 

[Yellow Ballad]

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