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davidyat

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Are there any EDM services here on HMEM? I'm building Vederstein's Dancer engine and manage to break off a 1/8 drill bit about 1/2 inch into the hole for a steam transfer port in the engine block. You can see that one hole that's buggered up pretty good. Could I make another? Yeah, but I don't want to.
Grasshopper
 

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Are there any EDM services here on HMEM? I'm building Vederstein's Dancer engine and manage to break off a 1/8 drill bit about 1/2 inch into the hole for a steam transfer port in the engine block. You can see that one hole that's buggered up pretty good. Could I make another? Yeah, but I don't want to.
Grasshopper
Where abouts are you. I could do it for you. I'm in the UK, Lincolnshire to be more specific. Happy to help.
 
Andrew,
Thanks for you response. I live in Indianapolis, Indiana USA. But I did have enough material left over that I decided to teach my self a lesson. I made a 3rd block and machined that one to specs. While I was machining this 3rd block, I kept remembering what I did wrong and vowed not to do that again!!! I now have my 2 engine blocks made. And again, thank you for your response and offer to help. But as you can see, I don't need an EDM service anymore. But I will keep you in mind if I need help in the future.
Grasshopper
 
If the part is aluminum as it appears, a solution of Alum and water heated to near boiling will dissolve the broken steel the next time if ever necessary.
 
Alum is a Houshold compound used in canning and food preservation. I\'m not sure of the concentration but mixed with water and heated near boiling, it will dissolve HSS drills and taps. Several reheats will be necessary and i used a bit of Sulfuric acid the one time it worked for me. I'll try to find the concentration online. This only works for aluminum.
 
It will dissolve any steel so only use on non ferrous components, one of the tricks to help things along is to have a hypo with some mixture in it and slide down the flute of the broken tap to flush new alum mixture down the hole, speeding up the process. I just stand my tub on top of a warm radiator.
 
Just remember to get the right kind of Alum, there are 4 different kinds being sold. I did not get a label on Mine and do not know which one it is. The wrong one I got before did nothing spending a week setting on top of a warm wood stove.
 
Are there any EDM services here on HMEM? I'm building Vederstein's Dancer engine and manage to break off a 1/8 drill bit about 1/2 inch into the hole for a steam transfer port in the engine block. You can see that one hole that's buggered up pretty good. Could I make another? Yeah, but I don't want to.
Grasshopper
Try Automotive Machine Shops.
Most have service for removing broken bolt and the do tap and drill bits too. Most use a EDM machine just for that work.

Dave
 
It will dissolve any steel so only use on non ferrous components, one of the tricks to help things along is to have a hypo with some mixture in it and slide down the flute of the broken tap to flush new alum mixture down the hole, speeding up the process. I just stand my tub on top of a warm radiator
I drilled some broken taps out with small carbide ball endmills (this will ruin at least one or two of the endmills :cool: ) it takes a long time and might ruin the part for good if the carbide gets stuck. Can I re-do the part in less time than the tap removal takes? -> scrap box. Start over. If the part needs to be rescued I ask the friendly neighbor for help. (sinker EDM)
 
Are there any EDM services here on HMEM? I'm building Vederstein's Dancer engine and manage to break off a 1/8 drill bit about 1/2 inch into the hole for a steam transfer port in the engine block. You can see that one hole that's buggered up pretty good. Could I make another? Yeah, but I don't want to.
Grasshopper
This does not help now.
But when I first started I would do all tapping first.

Dave
 
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