View Full Version : Grinding parts on the lathe

01-15-2005, 05:31 AM
What do the members here think of using a tool post grinder or something like it on a lathe....

Do you have the potential to prematurely reduce the woking life of the lathe with grinding grit getting where it shouldn't.

I have made an attachment to attach my dremel to the tool post and have used it to grind certain parts that are hard...Should I not do this...I used to put a cloth over the ways when doing it...

01-15-2005, 08:04 AM
Darn right it can shorten the life of things but sometimes that's what has to happen. I would suggest a coating of oil on the ways and any other ground surface as well as a wet cloth to cover the ways. A good cleaning afterwards to remove any grit is essential as grit seems to migrate when left alone. I don't like grinding on a lathe but if a grinder isn't available then take precautions and hit it sparky.

Forrest Addy
01-15-2005, 09:58 AM
A dremel because it's so puny puts out little abrasive compared to a tool post grinder or a die grinder mounted as a tool post grinder but it's still a source of ruinous debris.

I strongly suggest tenting the lathe with polyethylene film to isolate it as amuch as possible from abrasive and swarf, installing a fresh filter and drywall bag in your shop vac, and mounting its suction very close to the point of Dremel operations. Done right there's noting exposed but the chuck, the grinder, and the vac hose. You reach under it to operate the late controls.

When cleaning up vaccuum the tenting and the surrounding area (do NOT sweep!) to the extent possible ad roll up the tenting material from the edges to the center to trap debris.

I've worked on several machine tools subject to tool post grinding operations. It's amazing how litte abrasive contamination it takes to damage over time ways and leadscrews/nuts. Unless obsessive/compulsive precautions are taken open dry grinding will reduce a manual machine tool's life to as little as a quarter of its normal expectancy depending on the quality of precautions and cleanup afterwards.

Dry grinding can be done on conventional manual machine tools with no harm at all; just be sure to use surgical procedure style anti abrasive contamination technique.

01-15-2005, 01:55 PM
Maybe the bearings in your Dremel tool are better than the ones in mine, but when I tried using mine as a toolpost grinder I found the chatter marks were pretty bad.

As others have said...protect EVERYTHING, and do a thorough cleanup afterwards. Aluminum foil may be safter for covering than a cloth, as if it gets caught it will tear. A wet cloth, though, will capture the grit better.

01-15-2005, 02:04 PM
Forrest, How about floating abrasive dust from the grinding. Does it affect other machines nearby?

I've thought about a mini sized flood "tent" around the work area with poly film directing coolant down to a small holding tank/can with pump. Gotta clean up the abrasive laden coolant but no dust. Ever seen local containment like this? Den

01-15-2005, 03:03 PM
Releted to this issue, I've wondered just how much abrasion is found in normal everyday dust floating around. Obviously in areas prone to dust storms, such as the middle east, and our own desert SW U.S., there will be substantial abrasive material suspended in the air. And tho the particle size is relatively small, I'd think there'd be so much of it that it could cause considerable wear in short order.

But what I've wondered is how much damage potential normal household dust, such as settles out on your furniture, can cause.

01-15-2005, 07:09 PM
A shallow pan of water under the grinding wheel will catch most of the dust, leaving a lot less to cause trouble.

01-15-2005, 07:19 PM
Abrasive in the air is a problem most folks don't consider every time they fire up a sander,buffer,side grinder even a bench grinder.Chopsaws are by far the worst,we have one at the back door of the shop at work.It was slinging abrasive all over the place from day one when I started there.When the sun was shining through the dust cloud you could see all the little AOX and fiberglaas particles shining like glitter.I timed it oneday and found that one quick cut in 1" angle iron kept dust suspended for a good 30 minutes.

Not to mention that your breathing all that crap.The saw is now on casters and gets shoved outside at the start of everyday.I am still thinking of water coolant on it thou,for more reasons than one.