Removing flat head screws!

[stephen_h]

I need to replace a plastic jammer that is screwed to my ali mast
with stainless steel flat head screws.

Tried with a screwdriver and no luck. Have sprayed with penetrating fluid.

Heat would be good but jammer is plastic so was thinking I need an impact driver?

Any recommendations for one of these?

Cheers

 

[johnmcc]

Is the thread chewed up or in good nick? I'd start with the correct size screwdriver bit in a ratchet handle from a socket set to give you maximum leverage - but the correct size bit is the important part. You could try applying localised heat to the screwhead with a soldering iron. Impact driver would be the weapon of last resort for me, due to the damage you can do!

 

[rogerthebodger]

I need to replace a plastic jammer that is screwed to my ali mast
with stainless steel flat head screws.

Tried with a screwdriver and no luck. Have sprayed with penetrating fluid.

Heat would be good but jammer is plastic so was thinking I need an impact driver?

Any recommendations for one of these?

Cheers

Don't waste you time , drill off the heads , remove the plastic fitting then cut off the screws and relocate the fitting or drill out the remainder of the screw then fit rivnuts to refit the fitting

 

[Graham376]

Don't waste you time , drill off the heads , remove the plastic fitting then cut off the screws and relocate the fitting or drill out the remainder of the screw then fit rivnuts to refit the fitting

+1

 

[FairweatherDave]

Oil doesn't work with aluminium corrosion.
Kettle of boiling water might work if you are very lucky.
But expect to go for the drill approach.

 

[Graham_Wright]

What sort of flat head screw? Cheesed, countersunk, domed countersunk, straight slot, star slot?

The type determines the technique.

 

[coopec]

Surely a cordless impact wrench would make short work of them?

But I have also used an impact wrench that you hit with a hammer and they are good,

 

[penberth3]

This might be stating the obvious, but tightening first to break the bond can help.

 

[ShinyShoe]

Surely a cordless impact wrench would make short work of them?

But I have also used an impact wrench that you hit with a hammer and they are good,

Any risk of denting the mast?

 

[Dipper]

I've had a hand held impact driver for maybe 45 years that I hit with a lead mallet. It has never failed. It's very unlikely to damage anything because it operates via a spring mechanism and basically I am hitting a spring. It's been one of the best tools I have ever bought.

 

[coopec]

Any risk of denting the mast?

No. I was given one and it works like a drill in that it turns clockwise or ant-clockwise. But as it turns the screwdriver bit it has a rotational impact action.

IMPACT DRIVER
https://www.youtube.com/watch?v=EHYlZFs1g-I

I agree with what Dipper says but he is talking about a manual impact driver

 

[Dipper]

This one looks virtually identical to mine and shows the springing effect when it is pressed or hit (around 3.00 mins into the video). I do sometimes find that I have to hit the driver repeatedly especially if the screw is still stiff even after it has initially been turned.

https://www.youtube.com/watch?v=cUSuSn_QZmk

 

[stephen_h]

What sort of flat head screw? Cheesed, countersunk, domed countersunk, straight slot, star slot?

The type determines the technique.

They are countersunk, straight slot.

I know getting the right size bit is important and really don't want to be drilling
large stainless countersunk heads off! Might be the last resort.

 

[rogerthebodger]

They are countersunk, straight slot.

I know getting the right size bit is important and really don't want to be drilling
large stainless countersunk heads off! Might be the last resort.

I don't know what the diameter of your screw is but I have tried to unscrew 6mm hex head set screws corroded into my aluminum mast and sheared the bolt leaving part of the thread still in the mast.

8mm are a bit stronger and the hex head tends to round the corners with a ring spanner.

You will not get enough torque to shear a 6mm bolt with a slotted head

 

[Buck Turgidson]

big screwdriver and a spanner round the shaft. Failing that drill em.

 

[AndrewB]

Tips on how to drill out a stainless screw corroded into an aluminium spar, much appreciated please!

Whenever I try, I get (very slowly) though the screw head, then inevitably the drill bit slips to one side and chews though the much softer aluminium of the spar, leaving the body of the screw behind. If I then lever out the remains of the screw, it leaves a huge hole.

 

[Buck Turgidson]

Thin pilot hole first, then move up size by size. Small chips.

 

[Pye_End]

A brace might be worth a go. Lots of leverage and you can put plenty of pressure on the screw. However, if it doesn't want to move it will snap the screw - an impact driver is perhaps a better first stage.

 

[Humblebee]

I've had a hand held impact driver for maybe 45 years that I hit with a lead mallet. It has never failed. It's very unlikely to damage anything because it operates via a spring mechanism and basically I am hitting a spring. It's been one of the best tools I have ever bought.

Another vote for an impact driver. I've had mine about as long as you Dipper. Seldom used but golly, when you need one you need one, and it works brilliantly.

 

[PaulRainbow]

Don't waste you time , drill off the heads , remove the plastic fitting then cut off the screws and relocate the fitting or drill out the remainder of the screw then fit rivnuts to refit the fitting

Just for a change, i'll agree with Roger