loosening rusty screws!

[Robbox]

I have an Ercol table that I want to refinish, top and base. It will be a lot easier to handle if I can separate the leg assembly from the top.

It's screwed to the top using slotted screws but they are quite rusty. I've tried my cordless driver but I think the corrosion is holding them too tight.

I have an impact driver, but I'm concerned this could snap the screws below the surface.

Any suggestions on how to remove safely? Is there an oil or something like WD40 I can use to free up the corrosion?

 

[just pumps]

Try an old fashion tool called a handheld screwdriver, just use the correct sized one.

 

[footprints]

Penetrating oil is best, very thin almost like paraffin in viscosity, it may stain the timber though try a little dam of plasticine or blu-tack around the screw head to reduce the amount running down the outside of the leg.

 

[foxhole]

Snapping the screw should not be a problem.

 

[Robbox]

Penetrating oil is best, very thin almost like paraffin in viscosity, it may stain the timber though try a little dam of plasticine or blu-tack around the screw head to reduce the amount running down the outside of the leg.

Thanks, I think I will try this. The screws are recessed, so the oil has nowhere to go but down the screw....

 

[ETAF]

you could also try to tighten first, often helps release screws.

 

[Burnerman]

Time to break out the traditional boxwood handled cabinet screwdriver that fits the head size perfectly....turn the table upside down, press the driver firmly down with two hands and turn.
The screw will shift 99.9% of the time.
John

 

[lostinthelight]

Time to break out the traditional boxwood handled cabinet screwdriver that fits the head size perfectly....turn the table upside down, press the driver firmly down with two hands and turn.
The screw will shift 99.9% of the time.
John

I find I can get even more pressure by forcing down with my head with my chin on top of my hands .may help with the last .1%

 

[JohnD]

heat on the head of the screw will certainly help. Unless you have a torch with a pin-sized flame, a soldering iron held against the head will be quite effective. Stop when you see a wisp of smoke.

 

[ellal]

A few whacks with a hammer on an old fashioned hand impact screwdriver?

 

[Burnerman]

The shock may snap the head off - who knows? Personally I've had limited success with these things but a good bash down on the screw with the correct size driver and then turn will shift things.
John

 

[lostinthelight]

It also helps if the end is ground parrall or slightly hollow ground so it bites lower in the slot instead of like a chisel which cams out.
I regrind various size bits hollow for brass screws and carb jets which are more prone to damage

 

[Munroast]

as for snapping - depends on what steel it is made from, the signs of rust and a slot head probably means it is old, the steel used then was quite malleable so will tend to bend or twist a long time before snapping. Modern screws are a much harder high tensile steel and these are the once that seem to snap if overloaded.

 

[Diver Fred]

Probably to late but my advice.
make sure the screw heads and slots are clean and not covered in varnish or paint.
with a screwdriver that fits the slot (exactly) in the slot hit the handle of the screwdriver with a hammer two or three times - about the force to knock a inch&half nail in.
try to tighten the screw before trying to loosen the screw.
those two actions usually break the 'seal' and allow the screw to be undone.

 

[Robbox]

Probably to late but my advice.
make sure the screw heads and slots are clean and not covered in varnish or paint.
with a screwdriver that fits the slot (exactly) in the slot hit the handle of the screwdriver with a hammer two or three times - about the force to knock a inch&half nail in.
try to tighten the screw before trying to loosen the screw.
those two actions usually break the 'seal' and allow the screw to be undone.

Hi and thanks, project not started yet! Lockdown Lethargy to blame.....
I agree with your methodology, a couple of good whacks should release the screws.