Page 1 of 1

Alum for broken stud removal

Posted: 24 Jul 2017, 23:03
by Walrus
Just seen this video on YouTube: https://www.youtube.com/watch?v=fqZYgReuywM, using Alum to remove a broken stud. Would this be safe to do on a VW T25 engine? It may not be quick but it *looks* easy...

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 01:56
by Oldiebut goodie
No reason why not provided you can devise a suitable containment for the solution around the offending steel stud/bolt. Saves wrecking the threads in a valuable case. I am surprised that it isn't used more rather than the heat/welding etc techniques.

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 07:20
by itchyfeet
Thanks, will be trying this :ok

Where would you buy Alum?

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 08:10
by Walrus
Health food shops apparently! or Amazon/fleabay sell it for ~£5 for half a kilo.

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 08:24
by itchyfeet
maybe Asian shops too, Fatakdi powder

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 08:35
by multisi
Interesting and funny - keep yer dick in a vice :rofl

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 09:05
by itchyfeet
same stuff?

Aluminium Sulphate 17% Iron free Al2O3  in sulphate form.

http://www.ebay.co.uk/itm/500g-of-ALUMI ... 1123026367" onclick="window.open(this.href);return false;

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 09:25
by Oldiebut goodie
I think that it is the potassium alum that is generally used. KAl(SO4)2.12H2O may be wrong though. :D
But then I have read of the ammonium alum having the same effect so it may not matter too much, speed of reaction different?

Re: Alum for broken stud removal

Posted: 25 Jul 2017, 10:34
by itchyfeet
Looking at Alum page on wikipedia I think its
Aluminium potassium Sulphate
Or Potassium alum
or Fatakdi powder

Re: Alum for broken stud removal

Posted: 26 Jul 2017, 19:46
by Mr Bean
Well I like the idea as it would appear to be a bit cheaper than Spark erosion and in some cases do able in situ.
I am surprised that I never came across it as a Salvage Scheme (Posh Bodge) when I worked in Aerospace. :ok
CS

Re: Alum for broken stud removal

Posted: 26 Jul 2017, 20:55
by Oldiebut goodie
I can recollect seeing it mentioned on a Yank forum a long time ago but never gave it much thought. An ideal solution as a solution to those broken head studs that you petrol guys have trouble with. If it saves damaging an expensive crankcase well worth persevering with to get the remains out however long it takes. It seems to be effective with a supersaturated solution.

Re: Alum for broken stud removal

Posted: 28 Jul 2017, 13:41
by Mr Bean
As if we petrol heads would use anything else :rofl
CS