Sheared off screw

[lcochrane]

What is the best way to remove a screw after the head sheared off.
This is a brass screw which secured the plate over the impeller and the shank in stuck in place.

Thanks

 

[coopec]

Being such a nice bloke that I am I did a google to see if I could help you.

I had a bit of a chuckle when I read this

Broken brass screws. Aaaargghhh!!!!!!! - by Chinitorama ...
lumberjocks.com/topics/19008‎
Jul 27, 2010 - 15 posts - ‎13 authors
Worse still, I tried to drill one out and the bit snapped off in the hole as well. ... Remove the SS screws and replace with the brass screws.

 

[Gwylan]

What is the best way to remove a screw after the head sheared off.
This is a brass screw which secured the plate over the impeller and the shank in stuck in place.

Thanks

Oops.... Google helicoil?, effectively drill out the old bolt and insert a new thread. Or you might get away with a bolt extractor, but I never have.

Good luck....will be interested to see better, easier suggestions.

 

[coopec]

Like Gwylan I have never had any success with an "easyout"

Maybe there are suggestions here?
https://www.google.com.au/#q=remove+sheered+off+brass+screw

 

[Talulah]

What is the best way to remove a screw after the head sheared off.
This is a brass screw which secured the plate over the impeller and the shank in stuck in place.

Thanks

I've had great success with Grabit extractors.
http://www.amazon.co.uk/exec/obidos/ASIN/B000Y8IPWI/dolcetto-21#

Get a decent make. Demos on youtube.

 

[knuterikt]

What is the best way to remove a screw after the head sheared off.
This is a brass screw which secured the plate over the impeller and the shank in stuck in place.

Thanks

The traditional conical screw extractors is the worst tool you can use as the tend to expand/split the screw.

Get hold of some left hand drill bits with diameter equal to the inner diameter of the threads and smaller.

The problem with drilling is to get it exactly centered - there are some tools that can help with that (bit I have never tested those)

Start with small left hand drill bit - the theory is that the heat, vibration and the left hand drilling might get the screw moving.

If this does not help you have some options
- Screw extractor of the straight type
- Drilling larger hole (still using left hand bits)

If you manged to center your first hole you can drill with drill bit with diameter = inner diameter of the thread and just clean the threads with a tap.
Helicoil might be another way to get threads back.

 

[macd]

Just by way of clarification, Helicoil is of course a brand name for a type of thread insert. There are cheaper, simpler systems than Helicoil, more suited to occasional non-professional use. I've used Recoil inserts for years: excellent product.

 

[pete]

How big is the screw ? can you post a picture ? the more information you post the more relevant the advice you will receive.

I have had some success by carefully tapping an old screwdriver into the end of a broken screw and trying to unscrew it by tapping the screws end anticlockwise but it depends on the size of the screw for this (you may find that it was the only the screw head that caused it to snap) and the thread may be quite slack apart from the burr where it snapped.

Failing that from the info you have given I would refit the pump cover, find a drill bit that is a tight fit through the pump cover hole, and with the cover fitted drill in just enough to give yourself a center, replace the bit with the correct size for your required tap and re tap the hole.

Pete

 

[2Tizwoz]

Get hold of some left hand drill bits.....

This assumes that the screw cannot be screwed right through the tapped hole and come out the back. This can be the case with some pumps, in which case a standard right hand drill would suffice. If the remainder is long enough some heat and a pair of mole grips may do the job.

 

[ripvan1]

It this is on a pump such as Jabsco with 6 screws holding the plate, and assuming you've removed the others successfully, would it be possible to spin the plate thus undoing the screw from pump ?

Of course as said a photo would help.

 

[Neil]

I bought a Quikcenter (http://www.quikcenter.com/) set for drilling out broken bolts and machine screws, following a disastrous attempt to drill out a sheered off SS bolt from an outboard leg. It turned out to be of great insurance value - I've never had to use in the 3 years since........

 

[Lakesailor]

Failing that from the info you have given I would refit the pump cover, find a drill bit that is a tight fit through the pump cover hole, and with the cover fitted drill in just enough to give yourself a center, replace the bit with the correct size for your required tap and re tap the hole.

Pete

Excellent suggestion. I would go further and suggest once you have created the centred delve in the screw end to use a small pilot drill to create a good pilot hole. Drilling with a large drill may go off centre again, especially if it has a damaged or re-ground tip.

 

[ghostlymoron]

If its a normal woodscrew into wood, I usually remove them by drilling around them with a small diameter drill bit until I can grab the end with long nose pliers and then gripping it and removing it. Sometimes you have to drill down the full length of the thread before they succumb. After its out, drill a clean hole and glue in a hardwood dowel 6 or 8mm dia. I've never had much success with screw extractors and haven't got a suitable pillar drill to drill out a screw.

 

[lcochrane]

Thanks for all the replies.

The screw is about 4mm diameter.
It can't be screwed through the tapped hole.