Using A Helicoil To Fix A Stripped Thread - Coolercases UK

coolmiester · 15-02-2006, 11:34 PM

Helicoil has many applications and is a great way to replace a stripped thread and none better to show how its done properly than to use Unreals Storm G5 which suffered that very thing and was thought to be on its way to waterblock heaven.

Stripping the thread is a common occurrence with water blocks as usually they have a stainless steel bolts tightening down into a copper base which is a very soft metal or in this case a pure silver base which is even softer so a turn to much can easily strip the thread from the softer metal - all is not lost

There are a couple of methods that could be used and my first thought was to simply re-drill and tap the offending hole but this would then have left the dilemma of finding a new larger stainless steel Hex bolt so decided to try using a Helicoil which essentially is oversize drilling and tapping the hole then using a Helicoil to plug the hole to the same size as it were previously.

Anyway as you can see this is the base of the Storm G5

And on closer inspection you can see clearly the thread was in fact stripped good and proper

So first of all the hole was drilled out using a 4.1mm drill

So the hole was oversized like this

Then using a M4x.7 Tap, re-tapped the hole (2 turns in and 1 turn back to get rid of swarf)

So your left with a nice rethreaded hole like this...

This is a close up of the Helicoil which will be used to bring the hole back to the correct size.
As you can see its basically a small spring with a dog leg on the end called a "tang" which is needed to screw the thing in place.

A special tool is used to compress the spring so that it can be screwed into the hole - the idea is that once in the hole the helicoil will de-compress out over and attach itself to the threaded hole.
To start off with the small Helicoil is screwed loosely onto the threaded shaft of the tool like so...

Then the shaft is inserted into the body and screwed in so it compresses and just starts to protrude out the end of the tool which also has a threaded end - the Helicoil has no alternative but to compress in over

so the end of the tool looks like this...

That end is now placed firmly over the threaded hole on the block base and while keeping hold of the body of the tool, the shaft is screwed out which forces the Helicoil into the base

and from the other side of the base you can just begin to see the Helicoil coming into place

Once the Helicoil is flush with the base and the "tang" is just protruding the shaft of the tool can be screwed back out leaving the Helicoil in place

......and from the other side

As you can see the existing bolt now fits back into the hole perfectly

Using the tang removal tool which is essentially high tensile steel bar which fits the hole, it can be placed on a sturdy bench and hit with a hammer which removes the tang like so - leaving the hole flush to rest of the base with a perfect re threaded hole to accept the hex bolt.

Just like new

nyzrox · 16-02-2006, 12:31 AM

Nice guide paul, looks very nice how you have done that. wish you had time to help me

f.sardis · 16-02-2006, 01:03 AM

just how cool is that?

nice one Paul

UnreaL · 16-02-2006, 01:43 PM

Got a huge "IOU" sign for you Paul!

Great idea turning it into a guide, I wouldnt have known how to do it!

Looks fantastic! ill drop you a pm!

PHILIP1193 · 23-02-2006, 04:34 AM

thats a good guide mate, where do u get those "tang" things?

Phil

coolmiester · 23-02-2006, 08:26 AM

I got an Armstrong Helicoil Kit form Cromwell Tools which came with everything needed.

Can't seem to find it listed on their site but the code is M4X0.7 which might help

Hellboy787 · 23-02-2006, 11:59 PM

a very handy tool....I bet that tools is worth the money you spent....

15-02-2006, 11:34 PM	#1
coolmiester Administrator Join Date: Jul 2005 Posts: 3,788	Using A Helicoil To Fix A Stripped Thread Helicoil has many applications and is a great way to replace a stripped thread and none better to show how its done properly than to use Unreals Storm G5 which suffered that very thing and was thought to be on its way to waterblock heaven. Stripping the thread is a common occurrence with water blocks as usually they have a stainless steel bolts tightening down into a copper base which is a very soft metal or in this case a pure silver base which is even softer so a turn to much can easily strip the thread from the softer metal - all is not lost There are a couple of methods that could be used and my first thought was to simply re-drill and tap the offending hole but this would then have left the dilemma of finding a new larger stainless steel Hex bolt so decided to try using a Helicoil which essentially is oversize drilling and tapping the hole then using a Helicoil to plug the hole to the same size as it were previously. Anyway as you can see this is the base of the Storm G5 And on closer inspection you can see clearly the thread was in fact stripped good and proper So first of all the hole was drilled out using a 4.1mm drill So the hole was oversized like this Then using a M4x.7 Tap, re-tapped the hole (2 turns in and 1 turn back to get rid of swarf) So your left with a nice rethreaded hole like this... This is a close up of the Helicoil which will be used to bring the hole back to the correct size. As you can see its basically a small spring with a dog leg on the end called a "tang" which is needed to screw the thing in place. A special tool is used to compress the spring so that it can be screwed into the hole - the idea is that once in the hole the helicoil will de-compress out over and attach itself to the threaded hole. To start off with the small Helicoil is screwed loosely onto the threaded shaft of the tool like so... Then the shaft is inserted into the body and screwed in so it compresses and just starts to protrude out the end of the tool which also has a threaded end - the Helicoil has no alternative but to compress in over so the end of the tool looks like this... That end is now placed firmly over the threaded hole on the block base and while keeping hold of the body of the tool, the shaft is screwed out which forces the Helicoil into the base and from the other side of the base you can just begin to see the Helicoil coming into place Once the Helicoil is flush with the base and the "tang" is just protruding the shaft of the tool can be screwed back out leaving the Helicoil in place ......and from the other side As you can see the existing bolt now fits back into the hole perfectly Using the tang removal tool which is essentially high tensile steel bar which fits the hole, it can be placed on a sturdy bench and hit with a hammer which removes the tang like so - leaving the hole flush to rest of the base with a perfect re threaded hole to accept the hex bolt. Just like new __________________ MSN: paul@coolercases.co.uk Laptop Contact: mobile@coolercases.co.uk

16-02-2006, 12:31 AM	#2
nyzrox Hyper Member Join Date: Aug 2005 Location: Nottingham, UK Posts: 714	Nice guide paul, looks very nice how you have done that. wish you had time to help me __________________ Apple Macbook 13.3" 2GB Corsair DDR2 SO-DIMM PC5300

16-02-2006, 01:03 AM	#3
f.sardis CC Pro Join Date: Aug 2005 Location: London Posts: 2,897	just how cool is that? nice one Paul __________________ SLI Rig LAN Rig CPUZ

16-02-2006, 01:43 PM	#4
UnreaL Senior Member Join Date: Dec 2005 Posts: 148	Got a huge "IOU" sign for you Paul! Great idea turning it into a guide, I wouldnt have known how to do it! Looks fantastic! ill drop you a pm! Last edited by UnreaL; 13-04-2006 at 09:16 PM.

23-02-2006, 08:26 AM	#6
coolmiester Administrator Join Date: Jul 2005 Posts: 3,788	I got an Armstrong Helicoil Kit form Cromwell Tools which came with everything needed. Can't seem to find it listed on their site but the code is M4X0.7 which might help __________________ MSN: paul@coolercases.co.uk Laptop Contact: mobile@coolercases.co.uk

23-02-2006, 04:34 AM	#5
PHILIP1193 Member Join Date: Jan 2006 Posts: 52	thats a good guide mate, where do u get those "tang" things? Phil

23-02-2006, 11:59 PM	#7
Hellboy787 Member Join Date: Nov 2005 Posts: 60	a very handy tool....I bet that tools is worth the money you spent....