Gauge Pins

B

BROCKWOOD

H-M Supporter - Gold Member
H-M Supporter Gold Member
Joined
May 26, 2017
Messages
962
Not something I set out to buy or even collect. I'm just a hobbyist that fancies a precision part when I chuck it up. Yet, in my auction winnings there were always a pile a gauge pins included. Well, I needed to plug a hole. While the arbor supports for my VN 24 retain their oil at rest off to the side, the front 1 would leak when mounted. This was due to the end of the arbor being a bit shy; or not designed to poke all the way through. So, I organized those plugs, er gauge pins & found my next project. First the plug. Needed 0.447. I was gently sanding a plug down to size & in my frustration grabbed all the gauges out & began sorting them. It's always easy at 1st; just line em up by size. You, we must All answer: What sizes are of use? I don't know - nor do I feel qualified to answer. My solution, given what I have, is to reduce the size of all the repeats to fill in the gaps. This would give a more complete set. Managed 2 regrinds over the course of 4 days by hand. Well this will take a lifetime, so, I mounted my go to tool post grinder. Arr. Smaller tool post grinder is needed so switching to it.
IMG_20220613_161208407.jpg

IMG_20220613_161228441.jpg

IMG_20220613_161338045.jpg
 
My 2¢

As much as I am a fan of reusing and repurposing, I shudder at the thought of grinding gage pins to a new diameter. Precision gage pins can be purchased for around $4 each, less than $1 each if bought in a set. A gage pin should be perfectly round and of uniform diameter throughout its length. Measuring with a micrometer doesn't address the possibility of a pin having lobes. The value of a gage pin or any other standard, for that matter, is that it has trusted geometry and dimensions.

I have a set of .060" - .250" plus pins and one of .251" - .500" minus pins and use them quite often. Enough o that I am considering buying the complimentary minus and plus sets as that would give me pins at approximately half thousandths increments. I also make custom pins for larger sizes for a particular application. Those are simply turned to diameter from aluminum or steel and considered disposable. Grinding a hardened steel pin would open up a whole new dimension of effort.
 
RJSakowski said:
My 2¢

As much as I am a fan of reusing and repurposing, I shudder at the thought of grinding gage pins to a new diameter. Precision gage pins can be purchased for around $4 each, less than $1 each if bought in a set. A gage pin should be perfectly round and of uniform diameter throughout its length. Measuring with a micrometer doesn't address the possibility of a pin having lobes. The value of a gage pin or any other standard, for that matter, is that it has trusted geometry and dimensions.

I have a set of .060" - .250" plus pins and one of .251" - .500" minus pins and use them quite often. Enough o that I am considering buying the complimentary minus and plus sets as that would give me pins at approximately half thousandths increments. I also make custom pins for larger sizes for a particular application. Those are simply turned to diameter from aluminum or steel and considered disposable. Grinding a hardened steel pin would open up a whole new dimension of effort.
Click to expand...
I have similar sets purchased a couple years ago for a special project. At the time I didn't realize how often I would use them. The .061" to .250 set (190 pins) was a little under $50.00. That's about $.26 per pin. I couldn't even buy the material and the case to store them in for that amount let alone turn and grind them to size. The .251" to .500 set (250 pins) was $125.00. That comes out to $.50 per pin. Again far more cost effective to purchase them.

Not that I don't like running the machines, I just couldn't justify double the time and money to make them. I must admit I have resorted to dowel pins in some instances. McMaster offers them undersize, on size, and oversize. They're cheap and within .0002"
 
I use mine more than I thought I would. I also use my gauge blocks for sizing things that are too small for my adjustable parallels.

@BROCKWOOD You have 2 Themacs? One wasn't good enough? If I had 2, one would be the one I have and internal like yours. My other would be with the bigger spindles for external. I don't regret my purchase of the Themac, but it's limited for external.
 
I never felt the need for pin gages, I have a set of B&S tapered parallels with semicircular edges for gaging holes and also a set of B&S solid gages in nominal sizes from 1/4 - 3"; that combined with some drill blanks and other standard measuring tools gets what I need to do done well enough.
 
3/8 - 24 is what TheMac J-4 uses for a mounting bolt. I constructed a fixture plate that mounts to my combo carriage & all was well. I expected my other TheMac to use the same the same bolt size - but, no. My TheMac J-2A1 is just a bit smaller in every way. Yet I didn't have what was needed to modify countless pins accurately with the J-4 version. So, the J-2A1 would have to do. I've never mounted it (of course, I know it works). So, quick mod to the plate it is!

IMG_20220615_193004286_HDR.jpg
 
I thank you all for the responses.

Most are glad they have them. I think everyone agrees this looks like a waste of time. Since I had to get them out, I figured why not go ahead & organize them. Just makes no sense to have 3 to 5 of the same size. Why not hone my skills by rounding out the set?​


I'll start a new thread on the tool post grinders.
 
I would not grind such work with a small diameter wide wheel, but with a large diameter narrow wheel, more grit available, less chance of chatter and heat build up.
 
John, you are the best adviser I've ever had! I thank you for your input through the years. Looks like I'll take a few passes as is just to see & regroup.
 
You must log in or register to reply here.
Back
Top