On 05/02/2021 09:37, Tim Lamb wrote:
In message , Fredxx
writes
On 04/02/2021 20:29, newshound wrote:
On 04/02/2021 18:58, The Natural Philosopher wrote:
On 04/02/2021 16:56, JohnP wrote:
Kal Ico wrote in
:

I have a small air compressor and one of the fittings to the air tank
has sheared off.Â* You can see it he

https://photos.app.goo.gl/w44v8jSG2noBKVHv5

https://photos.app.goo.gl/xAaN8WTswVh6wuCQ6

Can anyone recommend the best way to get the old bit out and suggest
how to repair/re-thread so I can use it again?

Thans.

Stud Extractor

+1


Is that some sort of goo providing an additional seal? Is it hard or
soft? Either way, I think I would attack it gently with a
wood-working chisel to try to chip or prise as much away from the
interface as possible, as it will be contributing to the removal
torque. Ideally I'd try to make the thread interface visible, and
soak it with some sort ofÂ* penetrating oil. The very last thing you
want to do is apply so muchÂ* torque that you damage the boss or the
threads. Remember that a studÂ* extractor tends to expand the male
part, making it tighter.

I have used a punch or something similar to wind out a bolt. It may
loosen the thread sufficiently for a stud extractor to work.

Would it benefit from local heating prior to further rotational force?

There may have been thread sealant used which can sometimes be softened
by heat.

Softened maybe.

I have had the experience of heating up threaded parts where I
carbonises the grease/organic matter between the threads. The movement I
initially had disappeared and have since wondered if there was some
reaction incorporating the carbon into the steel parts.

Where you have dissimilar metals there is always the thought that
differential expansion can help. Brass has a thermal expansion
coefficient nominally twice that of steel.

After tentative easing with a stud extractor I would drill this out very
carefully. Worst case scenario if the threads are seriously damaged is a
helicoil.