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View Full Version : Will Grinding wheel dust ruin my lathe???



Mueller
10-22-2003, 03:35 PM
I was having a tough time turning down length of some Thompson steel shafting on my 3-n-1 (kept breaking carbide lathe tooling)

I mounted up a 6" grinding wheel to the mill head and now I can accurately grind away the offending material, fast and fairly accurate (I rough cut the shafting with an abrasive saw)

So, will the material removed along with the dust from the grinding wheel damage my machine? This stuff gets all over the place and my next batch of shafting that i need cut I planned on setting up the ShopVac to help.

Any other ideas??

Thanks

spope14
10-22-2003, 03:43 PM
Have to be careful here. Some say it will not, but from my experience, sanding dust and grinding dust can be an issue with machines.

I really clean up after grinding, use all oilers possible, and re-oil my machines after grinding on them. I try to prevent dust issues to begin with with rag covers to catch the dust on the ways and other bearing and mating surfaces.

After a grinding or rather intensive sanding session, i will not only clean real well, but will come back again the next tie, and use the oil "squirt holes" or the oiler system again to flush out any remaining stuff. If you have wippers on the machine, might not be a bad idea to take them off and clean them out - felt wipers that is. Clean with kerosene, blow out with air hose, oil the wipers, and put back on. The oiling of the wipers may not be necessary, but I do as a habit - light coat to "prime'. My machines have quite a front gap with the wipers off, and after initial flushes, I tend to move the machine a bit - wipers off, the ways clean aft and fore, and try to wipe up any remaining trapped stuff under the slide surfaces if there is any.

My machines are used quite a bit by students. In eleven years of the shop being open, the ways show minimal wear.


Maybe too careful, maybe not. The main culprit in all of this is nto the metals dust, but the abrasives that come free while grinding and sanding.

Joel
10-22-2003, 04:17 PM
It sure seems likely to be hard on the machine to me. I cover the ways or any sliding parts with a rubber sheet cut to fit, and rags if needed. I also use a shop vac on occasion. Oil the fool out of everything when finished, as spope says.

darryl
10-22-2003, 04:58 PM
I made an aluminum tray that mounts to the crosslide, to catch the grinding dust. There's a bit of a slant so cutting fluid can run off into the coolant tray below the bed. In my case, that tray doesn't interfere with anything unless I use a mt arbor, in which case, the cutter can't get all the way towards the headstock. With a chuck mounted, I don't need to remove the tray to be able to cut right up to the jaws. The grinding wheel is about centered over the tray, when the toolpost grinder is mounted. Most of the swarf is caught in the tray, which I made long enough to allow swarf to fall off the back and not land on the bed. The wind from the wheel blows the fine dust backwards, and it gets on everything behind the lathe. It might not be a bad idea to arrange a hood at the rear of the tray, with a vacuum hose to catch this 'overblow'. My first use of the tray was when I needed to grind some fiberglass rods to diameter, what a mess that would have been on the ways! Cast iron and any rusted metals will make lots of garbage that you wouldn't want on the ways, as well.
One drawback to this tray is from long curls coming off the cutter, they will tend to get drawn up into the spinning chuck more easily. I would like to improve this system by making the tray quickly removable, without tools. Currently, I need to undo one bolt.

BFHAMR
10-22-2003, 05:13 PM
Yes the grit can be hazardous to your lathe.

I saw a large South Bend once that had been used alot in an abrasive envionment. The ways up near the headstock were worn down at least 1/8". The ways were hardened but the carriage was soft cast iron. It acted just like a lap.

Dan

JCHannum
10-22-2003, 05:17 PM
Yes.

CCWKen
10-22-2003, 06:35 PM
It can also be hazardous to your health. Wear a mask. I learned my lesson with cast iron. I cover with plastic and tape everything down--even with the vacuum.

What a mess the first time; Took me three days to disassemble everything and clean up. That didn't count cleaning the floor and office.

If you don't clean it up, you might as well have poured sand on your machine. BIG-Time wear!

Forrest Addy
10-22-2003, 07:06 PM
I'd take it a step or two further. Grinding wheel dust wiil ruin yout lathe fairly quickly I'd say 100 to 1000 fold. Abrasive and oil makes lapping compound. Way wiper and felts unless maintained regularly will not exclude grit and oil.

The effect of the lapping compound is to wear the ways and turn the carriage and tailstock ways into a rocking chair. The grit will not "work itself out" by flushing with oil. You'll get someof it but the remainder will stay there and cause endless trouble.

If you used a tool post grinder on your lathe without tenting the machine so there was an impermeable barrier between the grinding operation and the machine slides you'd better take the machine apart and clean it, piece by piece.

I'm not kidding. Tool post grinders running on protected engine lathe will ruin them in rough propotion to the free abrasive and inverse proportion to a program of continuous cleaning as you go.

Tenting and and dust evacuation when tool post grinding causes no accelleration of wear provided when the job is done the tenting is vaccumed off and taken off but trooling the edges together so no tramp abrasive is aallowed to fall on the machine.

wierdscience
10-22-2003, 08:42 PM
Look at machines that are made to do grinding,the ways on these machines are hidden underneath the tables,they do that for a reason.

As stated above way wipers and scrapers won't work,in fact they have the opposite effect,they become loaded with grit and hold it accelerating the wearing process,on soft cast iron carrage components the grit can become imbeded in the casting making it almost impossible to clean.

Mueller
10-23-2003, 10:07 PM
Thanks all, I guess I'll be taking apart the machine to clean it up as best as I can.

I think now would be a good time to design a small machine with an X&Y table just for grinding (with dust evacuation as well)

dbehsman
10-23-2003, 10:34 PM
Just out of curiousity, what exactly is "Thompson steel shafting"? I was thinking that perhaps it could be annealed before machining, and then heat treated later. I think I read in one of Guy Lautard's books a story about a guy who did all of his metal turning on a wood lathe with a three jaw chuck and a hand file. I know with a little bit of patience and care, a person could do some very accurate work in this manner, but I don't know if it would be practical in this case. How much material are you trying to remove?

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Pat S
10-24-2003, 07:46 PM
An important rule with grinding machines is never use a air hose on them. Same goes with grinding on a lathe. Use a rag and push the dust away from the ways.

bernie
10-24-2003, 09:20 PM
Don't do it. If you must, you have to clean up everything before moving anything. All the abbrasive is in that dust. Grinding away if any thing rubs on it.

Bernie