Alum and brass with broken tap ??

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V 45

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I have read about the alum eating away broken taps. My questin is what about brass ? I have a small aluminum engine case with a 0-80 tap broke in it. It also has 2 small brass bushings already pressed in (.250" x .200" with a .125" hole drilled thru). Will alum eat the brass as well ?
Thanx again,
V 45
 
I've used the alum method with brass. I didn't notice any significant effect on the brass.

Bill
 
Thanx Bill. I didn't try it yet but I will this week sometime.
Thanx again,
V 45
 
I have done this successfully.

For best - read quickest - results, mix in the alum until the solution is saturated, then heat the solution and offending article. Maintain at just below boiling point and you will see tiny bubbles coming from the broken tap. This is the tap being eaten up with no damage to the brass.

Ian
 
i got some alum its sounds like its worth having it was only a buck no one told me if it works with bronze ? but i hope i never have to use it also will it eat a carbide tap?
 
So I got the alum an I was telling my machine tool technology instructor about the alum method a little wile later he called me over to a mill an where he was tapping some aluminum an said he would have to see it so he took a hammer a broke the tap off LOL here's to hoping it works
 
I have used alum powder several time and it does work but very slow. MAKE SURE YOU USE AN ALUMINUM POT.

Dave

P.S. dont ask why I know:(
 
Newbie- please direct me to where i can get ALUM - Reading PA.
 
Newbie- please direct me to where i can get ALUM - Reading PA.

You'll find it in the grocery store, either in the spice section or in the canning section. At my store it's in the spice section in a small 2oz bottle.
 
You can have the pharmacy order it for you in a large plastic jug as well.

Dave
 
Years ago when I was working on my taxidermy certification, I used to buy large
crystal alum from a local drug store.

It wasn't a store shelf thing.
I asked the pharmacist if they had it there and he sold me a pound of it for $8.00

Rick
 
In Oz you buy it at your local garden shop.


Best Regards
Bob
 
I am guessing a broken tap puller is not an option?

Over the past 30 years, I have seen more broken tap extractors than I have seen broken taps
that had been successfully removed by a broken tap extractor.

They will work on something larger than a 5/8" tap but that is far beyond the scale of hobby machining.

A machinist's job is to fix things.
Even if the the thing to be fixed was their fault.
:hDe:

It's a never say die venture.

If all methods of removing a broken tap fail, there are still options.

Get a cheap carbide drill or broken carbide end mill ground to a chisel point and drill the broken tap out.
Then drill the hole to a size that can be tapped to a standard thread and tap it.

Find a piece of material that is the same as the parent material and thread it to fit the tapped hole.
A little LockTite, thread it in, mill it flat to the original surface and try it again.

There are a lot of heavy machinery parts in use today with those repairs in them.
Some of them have letter/number code stamped next to them that would identify me personally as
being the machinist who did it.

I like being just a hobby machinist now!

Rick
 
Over the past 30 years, I have seen more broken tap extractors than I have seen broken taps
that had been successfully removed by a broken tap extractor.

They will work on something larger than a 5/8" tap but that is far beyond the scale of hobby machining.

A machinist's job is to fix things.
Even if the the thing to be fixed was their fault.
:hDe:

It's a never say die venture.

If all methods of removing a broken tap fail, there are still options.

Get a cheap carbide drill or broken carbide end mill ground to a chisel point and drill the broken tap out.
Then drill the hole to a size that can be tapped to a standard thread and tap it.

Find a piece of material that is the same as the parent material and thread it to fit the tapped hole.
A little LockTite, thread it in, mill it flat to the original surface and try it again.

There are a lot of heavy machinery parts in use today with those repairs in them.
Some of them have letter/number code stamped next to them that would identify me personally as
being the machinist who did it.

I like being just a hobby machinist now!

Rick

Thank you for the words of wisdom!
 
If you can drill a hole through the tap, you get way more surface area for the alum to work on and it should be much faster. It certainly quickened the process for me on a bolt I had to remove recently.

I used my anodizing gear to dissolve a broken bolt from an aluminum bracket. I just poured off a bit of the acid solution into a separate glass container and went to it.
 

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