Need a US machinist

I live near Washington DC. Machinists, welder, painters - nonexistent. I have a tiny job for someone with a milling machine that knows how to use it

I was removing the studs from a set of crankcases - simple task. The 3/8" top back stud seemed like it was Red Loctited in so I applied plenty of heat. The stud turned out one turn and stopped. A lot more heat and trying and finally the stud broke off. Needs to be drilled out and helicoiled and since it must pass through the other half of the case, accuracy is critical. There's a chance I could do it with a drill press but if I screw it up, there goes a numbers matching titled bike!

Jim Comstock is way too busy. Matt at cNw can't handle any more new jobs for a while. The only machine shop in my area took a month and charged me $120 to destroy a set of Triumph conrods (install small-end bushings and ream to size)

So, if you're a machinist willing to do a little job or know one that will do a little job and you trust, please let me know. marshg@gregmarsh.com

Hi Greg , i cant suggest anyone either sorry , another option could be spark erosion ? or make a 5/8 + thick guide to bolt on to a couple of other bolts to keep it on center . As for your conrods I think that is really bad , they shouldn't even be reamed nowadays ( lobe-ing) , even the machine shop i worked at 30 years ago had a pin hole borer , so easy .01mm clearance and there will be no drag on the gudeon pin . Cheers buddy .

Shelby-Right said:

Hi Greg , i cant suggest anyone either sorry , another option could be spark erosion ? or make a 5/8 thick guide to bolt on to a couple of other bolts to keep it on center . As for your conrods I think that is really bad , they shouldn't even be reamed nowadays ( lobe-ing) , even the machine shop i worked at 30 years ago had a pin hole borer , so easy .01mm clearance and there will be no drag on the gudeon pin . Cheers buddy .

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If I don't find someone my DIY fix may be a LONG bit, cases bolted together so the drive-side case is the drill guide and hope! Probably in two steps with a guide tube first and smaller bit. I have a drill guide I use to fix the barrel and head studs but there is so little surface to sit it on in that crankcase area it worries me. A thick DIY guide would probably work - I'll see what I have. I know I have a 2" think piece of aluminum I could use, but then I would need to get the hole through it precise.

Today I push in the Triumph small end bushings, install on the crank, and use the correct size reamer and DIY guide. Cost $70. Works perfectly.

marshg246 said:

I live near Washington DC. Machinists, welder, painters - nonexistent. I have a tiny job for someone with a milling machine that knows how to use it

I was removing the studs from a set of crankcases - simple task. The 3/8" top back stud seemed like it was Red Loctited in so I applied plenty of heat. The stud turned out one turn and stopped. A lot more heat and trying and finally the stud broke off. Needs to be drilled out and helicoiled and since it must pass through the other half of the case, accuracy is critical. There's a chance I could do it with a drill press but if I screw it up, there goes a numbers matching titled bike!

Jim Comstock is way too busy. Matt at cNw can't handle any more new jobs for a while. The only machine shop in my area took a month and charged me $120 to destroy a set of Triumph conrods (install small-end bushings and ream to size)

So, if you're a machinist willing to do a little job or know one that will do a little job and you trust, please let me know. marshg@gregmarsh.com

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I had a similar problem with a Honda cylinder stud a while ago and tried to drill it out; I do have a mill so was able to get the bit centered, but the stud broke inside the hole at quite an angle, and I couldn't use an end mill due to length issues, so I had to use a drill bit. I eventually got it out but the problem with the drill is it kept wandering into the aluminum. maybe that wouldn't be an issue depending on how your stud broke, but beware. The other thing to try is welding a handle/tab onto the stud. I've never gotten a chance to try it but a local machine shop said it works quite well, much better then trying to drill it out, since the welding heats up the stud enough to break it loose from the aluminum, and u can save the threads in the aluminum. That probably doesn't help much, but in the off chance that a welder is easier to find then a machinist...

Just a suggestion if you go to the bolting it together as a drill guide.
Can you use roll pins to protect the soft aluminum cases as a drill guide? Even going with thinner wall ones to step up to the point the stud becomes loose enough to to remove with a stud extractor such as: https://www.mscdirect.com/browse/tnpla/74782269?cid=ppc-google-Smart+Shopping+-+POP++Hand+Tools/Power+Tools&mkwid=|dc&pcrid=516119521412&rd=k&product_id=74782269&gclid=EAIaIQobChMIqMDhtrXo-AIVxt7ICh1VKQ3WEAQYAyABEgKoWvD_BwE&gclsrc=aw.ds I have found that the spline shaft tapped into the broken stud, spreads out the load along the whole broken stud, rather than flaring and tightening the top of the stud in the hole as a tapered easy out would do..
As to the removal of the stud to start with, I have had a great deal of success using a oxy/act torch with a welding/brazing tip in it to control the heated area, rather the broad area that a torch such a propane or map gas plumbing torch will give.
Heat the stud only, up to just turning red, definitely not orange, avoid warming the area around witch the is fastened. (remember old blacksmith shops were poorly light so as to see the color change in their metals) Then let it air cool until you can rest a bare hand on it comfortably.
Most the time I can get the stud out.
When heating just the stud, it will expand in the hole. This crushes corrosion and also pushes the threaded hole out a little wider.
After the stud cools and shrinks, it has a loosened the fit in the threaded hole.
I've used this many times on boilers, medium duty trucks, my pick up and motorcycles.
I have a 85 BMW R80 RT that I intend to use to get the exhaust rings off the head.
Stay tuned for how that works out.
I will claim success and admit failure.
If you want to do the math, steel expands at a rate of 3/4" per 100 feet, per 100 degrees F.
I do hope this helps in some way.

or induction, maybe not in your case , I have found KD square easy outs to be the only type to use,if you get a hole in the broken stud .not sure if they are still available , but as the don't have the helix they don't screw the remaining stud out to make it even tighter . Left hand drills can help to .

Greg
Have you tried chris greenbacker in Thurmont md. Can pm you his contact if needed.
George

baldy said:

Greg
Have you tried chris greenbacker in Thurmont md. Can pm you his contact if needed.
George

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Well, there's a senior moment for you - we're both members of the NCNO club - I'll contact him!

I've used this guy, and the local M/C shops use him.
He knows his stuff and is longtime motorcyle guy.

This past Monday I helped a frantic pal who had snapped off a cylinder stud in the engine case of his Lambretta, to make matters worse, he attempted to drill it out himself with a hand drill, which created an off centre non concentric hole. He then snapped off the easy out bit he tried using... double whammy.

He ended up hauling the partially disassembled case to my place (clutch housing still attached). I managed to the get the offending stud (with broken off easy out) machined out and without destroying the threads or concentricity of the bore. I still advised him to helicoil the hole regardless, but left that to him to solve. Hardest part was mounting the case (23" long) in the mill.

Sorry I'm not closer.

Is the broken piece a candidate for welding a nut on top of, and turning it out?

pressureangle said:

Is the broken piece a candidate for welding a nut on top of, and turning it out?

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No room to weld and it's stuck hard enough that I twisted it off - unlikely to be extracted - most likely must be machined out.

I have no experience with them. It would be nice to find someone local though

marshg246 said:

No room to weld and it's stuck hard enough that I twisted it off - unlikely to be extracted - most likely must be machined out.

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There are better ways. Jim's and Jerry's listed above are two of them.
Jerry's and it appears Jim's disintegrates the bolt, leaving the original threads.

MichaelB said:

There are better ways. Jim's and Jerry's listed above are two of them.
Jerry's and it appears Jim's disintegrates the bolt, leaving the original threads.

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I don't actually care how an expert gets it done and I've asked them for a quote. I can't imagine disintegrating a steel stud in an aluminum case but if that's the way to go I'm certainly OK with it. I just must end up with a matching number, titled bike and this is stopping me right now.

marshg246 said:

I don't actually care how an expert gets it done and I've asked them for a quote. I can't imagine disintegrating a steel stud in an aluminum case but if that's the way to go I'm certainly OK with it. I just must end up with a matching number, titled bike and this is stopping me right now.

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In the past, I have used alum;

I'm in Ottawa Ontario Canada. I've done exhaust port repairs for someone in Washington
and all over Canada.
I've also drilled and tapped honda crankcase bolts with cobalt mills after the customer broke off a tap. Shipping is on you. Can't quote without pictures.
Postal code for shipping is K0A 1L0