Burnerd Chuck Screws

[BrenM]

Usual reason for the end bursting is worn undersize key. My 4" dia. Burnerd uses 1/2 Whit. I used some studding drilled and broached the end and finished off with some Kasenit.

 

[Tractor Man]

Yeah, looks like a dodgy key broke them.

All three broken screws look as though they were all broken at the same time - surely the previous owner should of realised that something was wrong before breaking all 3 screws

 

[BrokenBiker]

like they say, common sense isnt all that common

 

[Tractor Man]

Totally agree!

 

[Tractor Man]

You'd think someone using a precision machine like a lathe would have a little common sense though!

 

[BrokenBiker]

youd think, we have a milling machine in work, usuall set up, bolt through the top to hold the various chucks and collet systems. one boke the other day left the spanner on and started it up on 1400rpm. one hell of a noise and a quick duck and panic later and we found it had snapped the spanner and threw it over 20 meters across the shop floor, luckily missing everything, and more importantly everone in its path. needless to say H&S officer wasnt impressed

 

[Tractor Man]

Ouch very lucky knowone was hurt.

It never surprises me the stupid things that people do and manage to get away with without any injury!

 

[BrokenBiker]

we are all assuming he will be given at minimum a written warning. and he was instantly banned from any machining for 6 months. he did go very very pale shade when he realised what had happened. but even so, it shouldnt have happened. as an apprentice i have been taught never to let go of the spanner unless you are putting it back on its hook on the shadow board, and this guy is training some of the mechanical apprentices

 

[Tractor Man]

I guess sometimes people just make mistakes - after all we're only human!

However as you say some things, especially when working with machines are inexcusable. When other peoples safety is on the line there is just no room for error!

Hopefully the person in question will learn from this and remember it next time they're allowed near the mill!

 

[FranV8]

Back to broaching a second, there was an article in Model Engineers Workshop a fee months ago on hoe to make a rotary broaching tool to fit a small lathe, it was being used to broach a hex shaped hole.

 

[Pete.]

Yeah you could quite easily make a square broach, only need a couple of degrees off-set angle and a piece of ground silver steel. I'd sill use a socket extension though.

 

[pjp123]

lathe bits

Hi

Try here . http://www.lathes.co.uk/

Give the guy a call he is very knowlegable and helpfull.

regards

pete

 

[Tractor Man]

Back to broaching a second, there was an article in Model Engineers Workshop a fee months ago on hoe to make a rotary broaching tool to fit a small lathe, it was being used to broach a hex shaped hole.

You don't happen to have an online link to this do you??

 

[awemawson]

Google 'rotary broaching'

 

[Big Pete]

A guy I used to work with had exactly the same isue, he bought some M20 (IIRC) socket head grub screws and machined the old thread off and the new thread on. He used a normal allen key for the chuck.

Alternatively, you can buy acme threaded bar stock in various pitches, a chunk of that cut to length, drilled one end and the cut off head ( short bit of shank left) of a cap screw TIG welded to it would work fine.