Lathe Tool Post Grinding Wheels Source

I recently purchased a used Dumore tool post grinder and it came with no grinding wheels. The wheels need to be approximately 1-1/2” to 2” dia x 1/4” thick x 1/4” dia hole arbor. Dumore and McMaster-Carr sell them. However, can anyone suggest other sources for a better selection of size, material, and grits?

4thTool

4thTool said:

I recently purchased a used Dumore tool post grinder and it came with no grinding wheels. The wheels need to be approximately 1-1/2” to 2” dia x 1/4” thick x 1/4” dia hole arbor. Dumore and McMaster-Carr sell them. However, can anyone suggest other sources for a better selection of size, material, and grits?

4thTool

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"BayState Abrasives" back in the day? Part of these folks, long time, already:

Radiac Abrasives | BRAND CONSOLIDATION - Radiac Abrasives

Another industry leader of long-standing- - part of France's St Gobain:

Norton Abrasives North America Homepage | Norton Abrasives

That said, and special needs or alloys being whatever they are, Dumore being still a "going concern", they aren't exactly 'unaware' of what works well with their TP grinders 'in general'.

If you are just starting-out with any one of their grinders, you could do a lot worse than to clock some experience with their own stock offerings first?

MMC don't list stuff exactly by accident, either. If they offer wheels or mounted points, there WILL be a market. Consider that a "vote of confidence" from the industry, in general.

Adapt to your special needs on experience, research, advice as to SPECIFIC goals and alloys from the user community as you learn what to ask for best effect and improvement.

Until then? "too broad a question". By far.

CAVEAT: No personal experience with Dumore.

I'm a McGonegal (TheMac) and (Rockwell-era) "Precise" guy.

In my book, Dumore / Hamilton-Beach are best for mixing lovely chocolate-malted milkshakes.

Very often a local tool supply shop can provide such wheels. Here around Detroit Production Tool supply is a source with having a few sites about town.
Often to buy a single or few wheels the local price beats paying shipping from the net.

PTSolutions | Abrasives & Finishing > Grinding Wheels > Surface Grinding Wheels | 3/4″ x 3/4″ x 1/4″ - Aluminum Oxide (32A) / 60J Type 5 - - Internal Dimension Wheel Surface Grinding Wheel | MG9059050

Machine Tool Supply in Los Angeles, CA with Reviews - YP.com

*But you are not likely to find 1-1/2” to 2” dia x 1/4” thick x 1/4” dia hole arbor.
A hole spacer is used to mount that diameter wheel that may likely has a larger spindle hole ID.

*Often a tool supply can recommend a good wheel choice.

Here find a set of wheels that I have never tried..All wheels should have a blotter so with these you may need to make your own blotters.
https://www.amazon.com/Amacupid-Buf...words=3"+grinding+wheel&qid=1622593299&sr=8-3
likely these are China (crap) wheels because any USA wheel would provide a blotter.

*Best just buy from Dumore*
Grinding Wheels | Dumore Series 57 Tool Post Grinder External Spindle

michiganbuck said:

*Best just buy from Dumore*
Grinding Wheels | Dumore Series 57 Tool Post Grinder External Spindle

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Those prices look unreasonable to me.... $126 for a 6" diameter 1/2" wide 36 grit AO wheel?

ballen said:

Those prices look unreasonable to me.... $126 for a 6" diameter 1/2" wide 36 grit AO wheel?

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Agree, the MSC prices are much better
https://www.mscdirect.com/browse/tn...heels/Internal-Grinding-Wheels?navid=12100093

https://www.mscdirect.com/product/details/96211073

Bought a couple from McMAster-Carr a while back. Seem to be decent, generic name brand, NOT made in China.

Thank you one and all. After researching the options contributed here, I decided on a two prong approach with my original sources, Dumore and McMaster-Carr. I’ll compare them and see which wheels I like best. Perhaps in the future I’ll come across another that I like better but for now I’m moving forward,

Thank you again,
4thTool

McMaster-Carr will sometimes quote custom or specialty tools. In my experience, their voice and email support people are very good and easy to work with.

Hi 4thThread,

Have you tried your McMaster Carr and Dumore wheels yet? Do you have a preference?

I might just buy from Dumore. I need to purchase a #2 sheave for my grinder. I have two #3, but no #2 :-(

I figure I'll bundle the wheels and sheave. I might get an extra belt while I'm at it.

One has to understand for a company to stock wheels, they have to have a market, and they can't simply just order five or ten. My company VersaMil Inc, was owned by Dumore back in the seventies, and I buy very specific wheels for my grinder heads. I have to order at least fifteen or twenty to meet minimums. I buy ALL of my grinding wheels now from Sandusky-Chicago grinding wheel Co. I Highly recommend them. The 1 1/2 to 2 inch diameter wheels you want are incredibly cheap to buy, to where even a part time user can buy 20 or thirty. ID wheels are a consumable. Unfortunately when they mix up the abrasive for the wheels, you don't get to buy one 40 grit, one 80 grit. Figure out what you need and order accordingly. I pay around $25.00 for six inch wheels, down to a few dollars for the small ID grinding wheels

I stock wheels, but frankly I'm not interested in selling small quantities of wheels to end users anymore. That's PROBABLY why Dumore charges a hundred bucks for a six inch wheel. Frankly I'm surprised anyone wants to use tool post grinders. YES it can be done, but WHY? I always use coolant when ID grinding, and having the luxury of having real grinders, makes me realize what a compromise, grinding on a lathe is. If you're going through grinding wheels, or even using up more than two, you're a very patient man.

Time or money.
I bought a lot of that stuff for my Cincy Tool & Cutter grinder on eBay. By the box.
You have to educate yourself about what specs might be appropriate for the type work & material you want to grind.

Then, if you can't find exactly what you need but something close is cheap, how do to adjust feeds and speeds to make it work the same?
Or like the tray of2" x 1-3/8" x 5/8" 60L wheels on eBay now, if the grit and hardness would work, then bush, & dress or present the wheel in use so only a corner, or only 3/16" face is applied*. Etc.

Per what Brian said, why ever, on a lathe, though?

smt

*PS not in anyway suggesting those for your app. They would take a lot of dressing and have more mass than might be advisable on your spindle (IDK). But the point is, there is a lot that comes up on eBay, Clist, and local auctions that can work, if you know what the essential specs are, and how to adapt the rest. There are actual Dumore wheels of the size you desire on Ebay as well, but they are listed at $19.99 ea and don't show any specs that would help suggest applications.

One can bushing down an arbor hole, and I have taken a dull carbide drill and crushed an arbor hole to a larger size. always good to have/use a blotter on any /every grinding wheel...even if you make one of a cereal box paper stock.

6oL that Stephen mentioned is a very common and very decent/useful wheel grade.

Making a grinding machine out of a lathe is a poor practice. Better to send the few grinding jobs to someone who has a grinding machine. Trade grinding time for lathe time.

Grinding machines are made so abrasive grit does not get into the precision parts.

Lathes are wide open to grits making a ruin of the machine...same for mills, they are not tight enough to be used as grinders.

Howdy Guys,

Thanks for the replies. I'm sort of hijacking 4thTool's thread for I thought you were responding to me. I didn't see that there were replies to this thread until today.

Why do I have a tool post grinder....well, I bought one about 10 years ago. Then the kids took more time, work took more time, etc. and I just didn't get out in the shop. Now the kids are graduating from college, I'm trying to pick up where I left the shop 10+ years ago.

I purchased a Whitney #91 press for cheap, and then I found out why. There is virtually no tooling for this thing in the wild. I am a hobbiest so part of the fun is trying to make stuff and learn the different techniques. I'm also basically a total novice and when I want to do anything - I'm basically buying stuff (this get's to be expensive and the wife notices). I have been making some packed carburized case hardened punch and dies sets for the Whitney #91 and thought it would be fun to try to use the tool post grinder to finish the punches and dies. I am also needing to make a MT2-3/4" case hardened straight shank adapter so my mill can use MT2 drills. I thought it would be fun to finally use this Dumore 44 tool post grinder, hence the need for wheels.

I'll keep my eyes open on eBay for wheels. I have been watching YouTube videos on how to use the tool post grinder (Mr Pete, etc). Tool post grinding is really slow, but it is about as fast as I am, so that is just fine. Due to Covid, I haven't been able to meet any of the guys in the machinist club and really don't feel right asking them to use their tools, etc. until I get to know them better and also get more skilled in my abilities. Hence, I'm trying to use what I have.

I'm looking for a 3/8" hole, 2 ish inch diameter wheel for my punches. This should be able to grind steels around Rc ~60. I'd also like to find a wheel for low carbon steel (1020 or ??). I'm going to figure out what I need to grind my dies and MT2-Straight adapter taper. I am thinking that Dremmel type of wheels should work for this purpose. What do you think? I have the adapter to hold a 1/8" shank wheel.

Thanks again,

Dave

Already replied my approach to wheels for grinders.

AFA the MT shank - what taper is your mill? These adaptors used to be about as cheap as new tool steel to make one (Mill taper to MT2) already hardened and ground.

If your mill is so oddball that is not an option, or if you want to do it for "fun", you could just turn the adaptor from something like 4140 prehard. If the best solution really is a straight OD, search "MT2 solid socket". Be aware they can be had soft or hardened, your choice. For turning or grinding to add features or reduce portion of OD,

If you choose to make a fully hardened part from toolsteel like A2 or something easy & then grind it, the fun part will be cleaning up the taper socket. You will need an extension arbor, a collet chuck or solid bar to hold the bob, small enough to fit about 2/3 of the way up the taper bore, and the 1/8" collet you arranged. & tons of patience. (Small, deep internal taper grind is not a good first project)

smt

techymechy said:

I am thinking that Dremmel type of wheels should work for this purpose. What do you think? I have the adapter to hold a 1/8" shank wheel.

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If you are ID grinding, the wheel will load up incredibly quickly. So the wheel diameter should be about 80% of the ID that you are grinding, to increase the time between dressings For stability the shank should be as big as possible. For me 1/4" is about the minimum size shank, and only if the hole is under say 3/8", otherwise I would go even larger on the shank size.

Aluminum oxide wheel like to run 4500 to 6500 with 5500 to 6500 surface feer per minute the most often advised, and often 6500 SFPM is given as the maximum.

But the wheel label is king and one should not run a wheel over speed.
SFPM = wheel dia times pi... Oh just use the short cut RPM x .262 (.26 is close enough)x the diameter.

Example spindle runs at 3400RPM, the wheel is 7" Dia.
3400x .26x 7 = 6188...

It is actually SFM 6235 but 6188 is close enough with .26 you can just figure it in your head.

slow SFPM usually gives a red spark and needs much more pressure to grind,(you are almost honing the part
with using a slow wheel.

Ref fron=m Dumore
Tool Post Grinder Grinding Wheel Speed | Dumore

Mostly wheels blow up expanding out from the RPM, but sometimes wheel pieces ricochets off bumping something, so no telling where one might be safe.

4000 miles away from the grinder with a wheel running at 5500SFPM at an ocean beach.. and darn you get eaten by a shark.

michiganbuck said:

... any USA wheel would provide a blotter.

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Umm, nope. I used to have boxes and boxes of Norton ID wheels in various sizes and grits, no blotters. Bought separate. Check them glasses for rose-tint, maybe ?