Help Please- Hi carbon Steel Grinding

I have a 1930 to1950's horizontal spindle grinder and very little knowledge on using it. Its accuracy has been fine when grinding mild steel but I need to grind some O1 and it is tapering badly and even bending off the chuck plate. The stone is a 34 grit white wheel(6"). My problem arises, I think, from heat build-up as there never has been a coolant sysytem on the machine (an Australian Macson with an Eclipse chuck) nor any place where one could be easily installed. Is dry grinding O1 absolutely out of the question or are there any basic requirements to make it possible ? If it has to be wet ground what fluid is needed and do I have to buy different stones to use with fluid ? I would be most greatful for any help and suggestions.
IMAGE(http://i301.photobucket.com/albums/nn58/bushmansedge/IMG_3793.jpg)
Sorry for the oversize pic.
Many Thanks,
Jim

Do you know the hardness of the wheel you are using? A hard wheel will dull quick (glaze) and produce too much heat. Dry grinding hardened material is not so bad as long as it isn't too long in lenght where heat will have an effect. Of course coolant would be better.

Thanks Mark.
I don't think glazing is the problem or at least it is not obvious and dressing the wheel makes no difference even in the short term. The steel in question is fully annealed but quite thin (just over 1/10" thick by 1/2" by 3"). It looks like wet grinding will be the answer but where does the fluid collector go ?

You Might try a spray mist. Don

Jim, I'm sure someone more knowlegable will chime in with the proper wheel chemistry so I'll focus on the cooling. I use a cold air gun so I don't have to mess around with coolant and all the maintenance involved. -Mike

Thanks Mike ,
That sounds practical. Can you tell me more about cold air guns. Sounds less messy than fluid or mist.
Jim.

Jim, you can see them here http://www.use-enco.com/CGI/INPDFF?P...MITEM=505-2081
If you search the general forum and maybe the new general forums for "cold air gun" or "vortex" you will find instructions on how to make one here on the board. There are several suppliers that sell them for <$150. Google could also pan out some plans for you. -Mike

Thanks Mike,
The linked site u
is temporarily unavailabe but I shall be searching the www shortly.
Jim.

This is the cold air gun I use. I do all my grinding dry (not because it's better, but because I can't deal with the mess)
http://www.airtxinternational.com/
One problem you may be having is that your piece is on the thin side for that design of chuck. The chuck may not be able to keep your piece from curling.
Light cuts and perhaps a softer wheel could help.

Any stock under 1/8" is always a problem with heat buildup, especially without coolant. As RJ said your magnet appears to have wide field spacing. This is not good for thin stock. Double stick tape may get you around the wide fields.
Try light cuts .0005 with cross feeds around .020" to .030" and fast table speeds. A slow table speed allows more heat to build up. Heavy cross feeds do the same.

No one has mentioned the position of the stock on the magnet. I was taught to place the stock at an angle and not completely parallel to the axis of motion. Ideally, to keep the heat from building up place the piece at 90 degrees to the axis of the wheel. On long pieces you are pushing the heat to the end of the piece where it does not like to jump off into the air.

No one has mentioned the position of the stock on the magnet. I was taught to place the stock at an angle and not completely parallel to the axis of motion. Ideally, to keep the heat from building up place the piece at 90 degrees to the axis of the wheel. On long pieces you are pushing the heat to the end of the piece where it does not like to jump off into the air.

LOL... I can just visualize little particles of heat jumping off the work...
Putting the piece on an angle can help if the configuration allows it.

Steelej,
I grind stainless tool steels regularly in my knife shop down to .088 with a dry wheel. But cool air works well also. I use it on the grinder sometimes and on my mill always. Just use a small piece of copper tubing run from an air line with a shutoff valve. Mine has a 1/16" hole in it. But I think your chuck is your main problem also. I use a fine line walker chuck with 1/16" spacers all the way. Never seen another like it actually. But I have tried other so called fine lines and they will not hold small work well. I make a lot of camshaft shims for Harleys out of hardened high carbon and I ground one this week down to .008 without any lift. I use a Norton 32a46-jvbe wheel. it is the best lasting and coolest running wheel for tough steels that I have ever used.

thewskrs
I agree with your wheel selection (32a46-jvbe) for roughing most ferrous materials. A better finish would of course require choosing a finer grit size depending on requirements. I have always been partial to the 32A series rather than the 38A. Others will not agree.

Is the O1 hot rolled and has black scale on it? If so, you are grinding away at fairly hardened steel. Try heating the steel up and cooling it slowly and then take a few licks at it and see if it grings like the mild steel that you had good luck with.
Have fun!
David

Ideally you should be able to grind flat and parallel regardless of material orientation. There will come a day when you'll have no choice but to place the workpiece the long ways on the chuck. Grinding the bottom of a slot is an example. Hone your grinding skills to prepare for all the what ifs. Wheel selection and dressing techniques are more important than placement orientation.

I was taught to place the stock at an angle and not completely parallel to the axis of motion. Ideally, to keep the heat from building up place the piece at 90 degrees to the axis of the wheel.

Is the O1 hot rolled and has black scale on it? If so, you are grinding away at fairly hardened steel. Try heating the steel up and cooling it slowly and then take a few licks at it and see if it grings like the mild steel that you had good luck with.
Have fun!
David

The O1 is fully annealed precision ground stock so firescale or surface hardening is not likely to be the cause of my woes, but Thank You for the suggestion.
Jim.

Steelej,
I grind stainless tool steels regularly in my knife shop down to .088 with a dry wheel. But cool air works well also. I use it on the grinder sometimes and on my mill always. Just use a small piece of copper tubing run from an air line with a shutoff valve. Mine has a 1/16" hole in it. But I think your chuck is your main problem also. I use a fine line walker chuck with 1/16" spacers all the way. Never seen another like it actually. But I have tried other so called fine lines and they will not hold small work well. I make a lot of camshaft shims for Harleys out of hardened high carbon and I ground one this week down to .008 without any lift. I use a Norton 32a46-jvbe wheel. it is the best lasting and coolest running wheel for tough steels that I have ever used.

It does appear that my ancient chuck may be most of the problem and that heat is the catalyst so air cooling and a new chuck may be the answers - pity it could be costly !
Thank You.
Jim.

steelej
Before you buy a new chuck you could try using a magnetic parallel. Less than a hundred dollars and usable with any magnetic chuck.

It does appear that my ancient chuck may be most of the problem and that heat is the catalyst so air cooling and a new chuck may be the answers - pity it could be costly !
Thank You.
Jim.

steelej
Before you buy a new chuck you could try using a magnetic parallel. Less than a hundred dollars and usable with any magnetic chuck.

Mike,
How does a magnetic parallel work please ? I have never heard of one before.
Thanks,
Jim.

http://www.cartertools.com/fmmpmv.html

Mike,
How does a magnetic parallel work please ? I have never heard of one before.
Thanks,
Jim.

Mike,
How does a magnetic parallel work please ? I have never heard of one before.
Thanks,
Jim.

The ferrous plates transfer the magnetic force to the part above. Since the polarity remains the same in each segment as the chuck on the bottom, it is of limited value in converting a wide spaced chuck into a fine spacing.

If you do decide to try a mag paralell make sure you block in your work very well. My experience is that there is about a 70% loss in magnetic pull through the usually 1" thick paralell.
Personally, I don't think the problem is the chuck but is with the heat. An air gun and a wheel change should do the trick. -Mike

I don't think the chuck is your problem at all.
Eclipse are top quality chucks, and thousands of the wide pole type are in use in toolrooms every day grinding thin stock.
It could well be the heat as others have said.
it could also be that the part is not flat when you put it on the mag chuck, and grinding can exacerbate this.
You need to check where it is bowed and pack undernath the bow (between part and chuck) with thin slips of paper to take up the gap before you turn the mag on.
Once you have done this you can grind the top, then flip it over and you should have a nice flat surface against the chuck, and then you can grind the bow out.
Peter

Thanks to all who made so many helpful suggestions. I have had a play with several of them and have concluded that heat was the real problem. In the longer term I hope to air-cool the work but in the meantime I have relieved the center 1/3 of the stone and together with lighter cuts and faster feed I seem to have arrived at a workable, if slow solution. I'm still trying to source a coarser wheel in Australia.
Many Thanks to all,
Jim

"I'm still trying to source a coarser wheel in Australia."

You want to get a courser wheel than 34 grit? It may help the heat problem but your finish will suffer unless finish is not a concern of yours.

Norton makes an EP (extended or extra porosity) wheel which will perform a bit cooler but I have never seen any wheel less than 46 grit state side anyway. Good luck to you and let us know what you find.

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