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getting out a blind hardened dowel pin...suggestions?

Eat the shaft with end mill. Not to size, smaller than shaft. Once center is chewed out drive the pin into opening. Heat it with micro torch, chew some more off/ repeat. I know you like small parts… there is an easy surface to work off right there on the bigger shaft.

The cheap spe taper bits off Amazon are go to for this work. Surface finish sucks, tool life mediocre but can take piss poor setup vibration and parts without snapping. Can take sub par feeds without breaking. Will chew the hard steel. When they do break they splinter length wise so getting the cutter carcus out it easy.
They come in packs of 6 for the same money as a single “good” bit.

Or- cut shaft clean. Drill clean hole down center 1/8 inch deep. Turn new shaft stub with a boss to fit drilled hole. Solder, braze, weld stub on. The gear is good, the pin is good/ don’t fix the working parts theory.
 
Are you actually as stupid as you come across or is it a front. I was using a 4 mm * through hardened pin as an example there are plenty of 2 mm through hardened pins in auto assemblies.
One thing's for sure - I'm not as stupid as you. No one cares what YOU were using, just like no one cares about your special gender assignment. Or your 4mm pee-pee. The point - tard -is that a 4mm pin is far more substantial than a 2mm pin. And there are hardly any 2mm pins in automotive assemblies...and if even if there were, they'd be stupid - which brings us back to you.
 
My first thought was same as moonlights.... TIG a nut or something you can attach a slide hammer to.
I've used one of these on a broken tap and it pecked that sucker out in a manner of seconds, if you can set this thing up in a mill? They come in 5/64" which is pretty close to 2mm.
 
I made my own combo collet chuck/pin puller for just this task. It uses 5C collets and a removable slide hammer. Also has a t-handle built in to the slide so you can give 'er a little twist if necessary.
 
One thing's for sure - I'm not as stupid as you. No one cares what YOU were using, just like no one cares about your special gender assignment. Or your 4mm pee-pee. The point - tard -is that a 4mm pin is far more substantial than a 2mm pin. And there are hardly any 2mm pins in automotive assemblies...and if even if there were, they'd be stupid - which brings us back to you.

And will the both of you knock it off already? Greg, you really want to turn this into a pee-pee measuring contest? For crying out loud. 🙄
 
@implmex knows some dental labs also, just take a 1/16" ejector pin, I know you have at least one lying around.
take it down to the dental lab, and have one of the PFM guys use the ole laser welder microscope and tack it on with a slide hammer on it first of course.
:D
 
Hi Donkey Hotey:
I didn't ask...The customer has been restoring these cars forever and he knows exactly what he wants and why.
I don't second guess him...he's been a great customer and I'm happy to make whatever he asks for.

I get these odd little challenges occasionally, not too different from those I get rebuilding injection molds and modifying surgical instruments and all the other weird and wonderful stuff I like to do, now that I care more about enjoying the experience than about making a pile of money.

Superbowl, that would be a great idea but...I just put a file to the gear and it's hardened...I'm guessing in the mid 40's to low 50's RC, so If I were to drill it, it'd have to be with the sinker.
Seems weird to put a hard pin into a hard hub, but it is what it is...German engineering at its finest.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com

One of my old shop neighbours in Port Kells, Renato, used to do a lot of work on those old Porsches, he did many body restorations for them and reproduced old race parts for them, as a lot of them were done up to be period correct race cars. Our shop has also powder coated many parts for those cars and new convertible top frames. Wondering if it's the same guy getting them done. Was always good to deal with.
 
Hi Houdini:
I have a laser welder that I bought on EBay years ago.
It came from a dental lab originally.
Super useful for me, and a very cool toy to own!

I'm going to give it a go...if it works I'll be a happy guy and post it on here.
If not, I'll post the failure, bite the bitter pill and set it up and burn it out like I did once already..

Cheers

Marcus
 
Hi Houdini:
I have a laser welder that I bought on EBay years ago.
It came from a dental lab originally.
Super useful for me, and a very cool toy to own!

I'm going to give it a go...if it works I'll be a happy guy and post it on here.
If not, I'll post the failure, bite the bitter pill and set it up and burn it out like I did once already..

Cheers

Marcus
Nice score on the laser welder, I was going to buy one to repair molds, not many guys around who do that or know how, or have the correct equipment, especially on 7075.
I have a guy I ship next day, he repairs it that next day, and sends it back next day.
Sounds like a good side hustle. :D
 
Hi again Houdini:
Yeah, I bought mine for exactly that purpose.
Actually, I lie...I bought it because I had a big boner for it...I'd used one that resided in a buddy's dental lab and was hooked as soon as I experienced what it could do.

I pretended it was a justified purchase by marketing it for mold repair.
This was back when Chinese molds were still all crap, but people were buying them because they were cheap.
I fixed a LOT of Chinese molds in the late 1990's and all through the first decade of the 2000's... it was a modestly lucrative piece of my business and I also fixed a lot of worn out old dogs of molds that were really only fit for the scrapper.
Here are a couple of pix:
DSCN2899.JPG
This POS had been TIG welded by an idiot, and I was expected to fix it.
This is how it arrived from China...brand new mold.
Here's the attempted fix (well at least one part of it):
DSCN3094.JPG
It's still a POS, but it's probably still running too.


Here's another...this was a legitimate mold core that some Dumbass dropped on the concrete during a service:
DSCN3221.JPG
Here's some quality Chinese mold milling for you to admire and feel insecure in your own skills about:
DSCN1800.JPG
Here's one I've shown a few times already...this was a cavity insert dropped on another cavity insert...OOPS!
DSCN1946.JPG

I've got hundreds of photos like this one...it was a pretty frequent gig in its day.
I see almost zero work of this kind anymore...Chinese molds are now mostly pretty good and all the guys who knew me back then are all retired.

The younger guys don't want to pay for work like this so I don't do that much anymore.
I don't care...it was acceptable but it was never a real moneymaker like the lathe or the mill or the wire EDM is a moneymaker.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com
 
I thought of weld/pull also. But now that you have one out, can you ballpark the angle and drill from 180° & drive it out?
Hi moonlight machine:
That's actually a really good idea.
I wonder how tight those dowels are actually in there.
If they're not a press fit maybe I can laser weld a stub on and then use a dental slide hammer (for removing crowns) to pop it out.

I didn't even think of pulling it...I thought more of drilling it away.
I was a dentist too...pulling things should be like second nature to me.
I have no excuse :nono:

There are smart guys everywhere on this forum...thanks a bunch for pointing me in a new direction.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com
 
I thought of weld/pull also. But now that you have one out, can you ballpark the angle and drill from 180° & drive it out?
A 2 mm hardened dowel in a hardened gear sounds like it was not intended to be serviceable. Is there an old manual that might yield some gem of a process? The use of a dowel suggests that the orientation of the gear on the shaft might be critical.
 
Hi tdmidget:
You wrote:
"A 2 mm hardened dowel in a hardened gear sounds like it was not intended to be serviceable"

I'm sure you're correct...apparently most of these gearboxes were riveted together so the guts were not accessible to a mechanic anyway, and I assume the gearbox was intended to be replaced as a unit when it wore out.
As with all things old, when you can't just buy one anymore, more drastic approaches become justifiable.

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com
 
You mention burning a hole, but having a hard time lining up. Not easy, but if you burn a 1 mm hole through the sort-of middle you can pack with grease and hammer a (short) 1 mm pin in to drive the 2 mm pin up.
Get the wall thin enough and it'll about collapse on its own, letting you pull it out with glue or an extractor.
Laser welder as mentioned.
Every now and then you get lucky and it's a steel pin in an aluminum part, but that doesn't seem to be the case here.
 
I've seen people do it with stripped bolts also, tig/laser a nut on them and unscrew them.
slide hammer'n I would think would be your best other than edm.

Like you said, I have always had to carbide drill and tap, but 2mm:scratchchin:

You were a Dentist, just use your root extraction tool:D
View attachment 431329
Drill in from the other side and knock it out with a punch
Don
 








 
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