EDM services?

There is a roll pin broken off in the crankshaft I sent to APE. I would have thought they would have mentioned something when it was inspected before work began; but instead they did $600 of work on a crank that it not useable :blink: yay!

Has anyone had any luck drilling out the ignition advance roll pin in the crank?

What does it cost to have a part EDM'ed? I am going to call a few local machine shops when I get the crank back, but I want to know how much more I will need to sink into this crank before it is useable.

APE won't help you ?

They don't do EDM work, so I am on my own it seems. Bummer right? The real kick in the pants is I have another hy-vo style crankshaft in a set of 750 cases... I would have pulled it and sent it if I had known this one was going to cause me a headache but I only found out about the broken pin AFTER the work was done.


Live and learn! I should have inspected the crank better before I sent it...

Is it like this one? (go to link and look at BlueMeanie's posting)

Sheared roll pin

Carbide end mill wont take it out?

stupid idea.... why not drill another hole just opposite?

you'll just need to swap the ignition wires. Even if slightly off from TDC, you can compensate with the ignition plate slots.

if its a roll pin, you should be able to fish it back out unless its benn mangled pretty bad.
anything you try to drill it with will walk off the side since the crank is softer than the pin.
EDM should work and is not very expensive considereing the work you have put into it, or they can set up on it in a mill and use a end mill to remove it.

But take it to a machine shop first, anything you try to do and mess it up will cost you more in the long run

I have worked in serval tool shops that did conventional EDM work... all of the machines were vertical head (they went up and down) and the "tub" which is usually full of kero was only about 18" deep... the workpiece must be flooded with this fluid for it to erode properly.
Your main concern would be fixturing it properly and if there is enough stroke on the head to do that length of part in that vertical position... if it was to be worked on while it is horizontal then it would not be a problem as even the smallest machine has a 24" x 24" "tub"... I have seen 96" x 144" tubs, but they are pretty shallow which could be a problem for most shops.
Expect to pay $80 - 120/hr for your part to be worked on - it might not be worth it when they are done... I can't see anybody doing EDM for less that $240

I would try everything in the world except EDM... I would go
to a tool supply and get some of there best drills which are usually sold as singles, 2 or 3 drill sizes different - drill it out in small increments untill it falls apart... cheap drills seem to make things worse.
Also try heating the crank end around the pin with a torch before drilling... it might just spin right out.

Find a shop that has a hole popper. We used one in the shop if we broke a tap in a hole. It is nothing more than an EDM that is designed to punch nothing but holes. My guess is that it would cost you about $40 to burn out.

Well I got a call from APE today; the only call they have given me in the two months they have had the crank, because I am short $8.00 on my total payment.

In short they still have the crank, and will hold it till they get their 8 bucks :laugh: but someone there is going to see a local (to them) shop can EDM it out before sending it back. It would be awesome to get a $250 bill added on to this.


I need a photo chop of someone slapping their head saying "I should of had a falicon" :laugh:



I would think a carbide end mill would make short work of it as well; but when the folks at APE tell me it needs to be EDM'ed I just shrug... what can I do at this point?

I would not be surprised if they broke it off and than make you pay for fixing it. Service today just isn't what it used to be!

where's Jay?