removing old screws - any ideas

[Burnham_Bob]

This must be a perennial problem, but my fore hatch has a broken hinge. The hinge attached to the hatch with bolts - no problem I can get them off, but it attaches to the deck with self tappers through a raised moulding which I presume has a wooden insert into the grp.

Naturally the screws are old and seized in. My screwdrivers are chewing up the heads so I stopped before it gets too bad. There is still a reasonable slot left.

Any suggestions before I drill them out and use bolts all the way through the grp to the inside of the cabin roof?

 

[sarabande]

try an impact screwdriver first, then variations with hot water, icecubes...

 

[Scarboroughsloop]

Apply screwdriver - smack with hammer, a good smart single shot. The hit can loosen the grip and make it undoable (if that is a word!)

 

[Alcyone]

Yep, I'm with that too. Rusted/old screws and nuts often respond to a hard shock. Just make sure it doesn't slip!

 

[Evadne]

Are they big enough to drill a hole in the top and use a screw extractor? (example)

 

[Hardley]

A bit late now, but I was instructed, to always try tightening old screws first, just a fraction of a turn, is enough to break the seal.
Others have given you good advise, but you might have to prop up the inside, if hammer and screw driver, makes the fibre glass flex.

 

[MoodySabre]

You can also break the bond by tightening the screw up a bit before trying to undo it.

 

[FlyingDutchman]

What sometimes helps is to clamp a mole grip to the handle of the screwdriver.
You can put your wight on the screwdriver ten and turn it with the mole grip. This prevents the screwdriver slipping out of the slot. Worth a try.

 

[saltwater_gypsy]

Try using a soldering iron on the head to break the bond and the tighten before undoing. Impact spanner is possible but may craze the GRP. Finally drill heads and get to work with mole grips or go for bolting as you first suggested.

 

[Poignard]

If you have done this already, then please accept my apologies, but have you made absolutely sure that what you say are self-tappers aren't in fact machine screws with nuts inside, hidden under some ceiling or trim?

Why do I say this? Because yesterday I found that one of the many screws holding one of my genoa tracks in place, and which normally screw into Helicoil inserts, goes right through and has a nut on the end [in addition to the one holding the spanner]. This was hidden under the ceiling which I am sure has not been off since the boat was built 46 years ago. Obviouly the builder spoilt one of the Helicoils and, to save removing it and fitting a new one, just drilled right through and put a nut on the bolt.

 

[cashinone]

With a similar problem on a stancheon base a motor mechanic friend loaned me his square shanked screwdriver set which combined with a long handled spanner provided sufficient torque and control to remove the offending screw - I have now purchased my own but as with these things have not yet been used in anger. - good luck

 

[colingr]

Tis a law akin to Murphy's. If you have to borrow a special tool to get out of a fix, and then decide to buy one yourself, you will never use it again.

 

[lw395]

I've had good results using left handed drills.
As the bit grabs, it undoes the screw. Very good on abused pozidriv etc.
A set of screwdriver bits driven by a 1/2 ratchet is also good, if you can get enough force to keep the bit in the screwhead.
Heat is also useful, get a long screwdriver bit, hold it with a carpenter's brace, heat with blowlamp. This will deal with anything thats been 'permanently' loctited!
happy bodging!

 

[savageseadog]

Use a proper make of screwdriver Facom, Britool Snap-On etc. Make sure the screwdriver is the correct size and type for the screw. Philips is not the same as Pozidrive and with Pozidrive use the largest driver that will fit the head, there's 4 sizes (at least)

 

[pampas]

Have had dramtic useage from those new diamond crusted bits, brilliant idea, just wish they were available during my working days. Would have saved hours of sweat and toil. Screwfic, CPC, and eBay have them advertised.

 

[rich]

Try and borrow an rechargable impact screwdriver, I have just done 100s of bronze screws in my deck only a few broke, I borrowed one first too try,then got my own, I don't think I could have done the job with out it, a fantastic bit of kit.

ps the deck is 45 years old.

 

[Avocet]

Be careful with any kind of impact driver that needs a hammer blow. If you hit it too hard, you could induce stress cracks in the surrounding GRP.

 

[PetiteFleur]

I would also recommend an 18v impact driver, starting with the lowest setting and working upwards. Alternate clockwise and anti clockwise. Make sure the slot is clean and use a good fitting bit. Try hammering in the bit before slipping on the driver. Lean as hard as you can on the drill. I've just removed some very rusty screws from hinges on an old barn using the above methods.

 

[lw395]

You are persauding me to buy another toy. How have I managed without one all these years?
Seriously though, have heard great things about 18v impact guns, from old Landrover addicts among others. I just wouldn't use one for a year, then i'd find the battery was flat...

 

[explores]

If just a screw (no nut) use a brace with a srewdriver bit in it, masses of pressure and leaveridge.