Gage Pins For Parts...?

EmilioG

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I would like to make some pins with ID holes for press fit or loose fit and others with threads, male and/or female threads. The dimensions will be 8mm ID and 1/2" OD, 5" long, for one pin. male thread on one end.

Q: Can I use Vermont Gage class zz steel pins or is this metal not suitable for making small parts?
I like the idea of using the gage pins because they are already very accurate as to the OD sizes that I need.
I also like the black oxide pins. It matches the rest of the part. Please advise. Thanks
 
Gage pins are hardened, so you would need to anneal them or grind them to modify them. Gage pins are also not that long, at least the ones I have and have seen. They are also pretty expensive when bought one at a time. O-1 and W-1 drill rod have a pretty accurate diameter, not sure how accurate you need, and it is also available in fractional, number, and letter sizes, perhaps metric as well. It is also fairly easily hardened. Dowel pins are probably about what you have in mind, but they are already quite hard and quite accurate, and are difficult to find in odd sizes. Can I ask what you are trying to do or make?
 
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Thank you. I like what Will (Dark Zero) made from his Indicol 178 and a Noga centering holder.
I would also like to make gage holders for my Noga and Mitutoyo back lug. I know they sell holders for back
lugs, but I'd like to make my own configurations. The gage pins are long enough and they do make longer gage pins.
I have a few. What about drill blanks? or cutting an old drill bit shank?

or should I just turn a piece of O1 drill rod? The centering pin does need to be fairly accurate, I think.
The Noga centering holder uses an 8mm end, and like Will DZ, I don't want to use an 8mm R8 collet either,
I would have to buy one. Not a problem, but with a 1/2" r8, I could switch tools quicker.

I also like Wills' "IndiNoga" hybrid. Excellent idea. Looks like an attachment to the Indicol 178 to hold a Noga
centering holder.

Thanks. Maybe Will DarkZero will share his specs? I am no where the seasoned machinist that most of you here are,
so all help and advice would be appreciated. Thanks
 
It sounds like you are talking about a rod (and other attached parts) to put in the spindle or around the spindle nose for swinging an indicator to dial parts in or tram the table. If so, there is no need for accuracy in any of the parts, only a rigid enough setup so that flex and play do not cause problems. Same for indicator adapters. Yes, it is nice to have hardened and ground pins with a nice finish and black oxide coating, but the truth is that a stove bolt will do the same job, and accuracy will be the same. The accuracy is in the indicator, the holder can be a 2x4, or whatever gets it to the work. In the case of swinging the indicator on a mill, it is the milling machine spindle bearings where the accuracy is.
 
Yes. I was also thinking of making a "sleeve" for the Noga centering holder. The sleeve would be 1/2" OD and 8mm ID.
and use two countersunk set screws to hold it on. This, instead of removing the Nogas' 8mm end rod.
 
That is a good idea. The sleeve does not need high accuracy, just a solid joint when tightened. A split sleeve might be best.
 
For the "IndiNoga", the pivot arm hole is 6.35 mm. I would only have to open it up to 8.1 mm and it already has a set screw.
My Noga centering holder would then fit. The sleeve can be used on and off, making my one centering holder more versatile.
Why Noga uses LocTite? I don't really know.
 
We have often used gage pins for tooling where I work when we need a very wear resistant post in automation machines. But all we do is cut them to length, grind them to an exact length, grind a whistle stop flat on one side, and EDM a hole through them. Gage pins are typically 52100 steel, which is the same stuff ball bearing races are made out of. Mostly, now, we just buy the 52100 stock, it's a lot cheaper, but we still use gage pins for prototypes of new sizes. If you don't need that extreme wear resistance, drill rod is probably a better bet.
 
By the way, Emilio, if you aren't aware of it, 6.35 mm equals 1/4 inch.
 
Thanks Bob, yes, I know. I like working in metric. I think it's a better standard. IMHO.
I read that Vermont Gage pins are made from O1 tool rod, not hardened. They just finish and oxide some of them.
 
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