Adding a Metalworking Lathe into Sawdust-Ville

[JC Whitney]

Paul M's recent measuring wheel post led me to his trove of videos, among which was a visual tour of his shop space (thank you Paul). I was surprised to see a metalworking lathe sitting immediately next to benchtop drill press that is presumably used for wood a good portion of the time.

I'm about to add a small (Harbor Freight 7x10) metalworking lathe into my shop, and despite taking a large leap forward recently in terms of dust collection (still a work in progress), I'm having nightmares about scraping sawdust out of grease/machining oil.

Have been thinking about fabricating a dust-proof cover of some sort for when it's sitting idle... am I nuts?

[Barry Daniels]

It depends. If you are going to turning a bunch of steel parts then oily metal slag mixed with uncontrolled saw dust may be a reality. I have a really small metal lathe (Taig) that lives in my shop sitting on my Performax and it has been nothing but a joy. I avoid the conflict by keeping sawdust and oil to a minimum. You don't need to overdo the oil. A drop or two on the ways, now and then and a drop if cutting steel. Most of the time I am turning brass or nylon parts on the lathe which don't need any oil.

When I first got my lathe I took it apart to clean off all the oil and grease. Then I put a thin layer of paste wax on everything to prevent corrosion. On reassembly, only the heavy wear parts (the ways) got oil.

If sawdust is out of control in your shop, then you might want to make a cardboard box cover for the lathe.

[Bob Gleason]

I have a mini-lathe too and it is really great for making knobs and handles. I long to learn how to thread on it. Metal work , especially with the softer stuff like aluminum is a lot of fun. A good tip is never to use air to clean up your mess unless you like metal flake finishes.--Bob

[JC Whitney]

Thank you both. Barry: I’ve been putting off unpacking and cleaning the lathe as I’m in the middle of a couple of other house projects that I’ll never get around to finishing if I don’t get them out of the way first. Was planning on oiling after cleaning, but your cautioning about over-oiling has me headed off to do a bit more research. Bob: I think the hardest thing for me is going to be avoiding wiping away swarf with my fingers, or not blowing chips to avoid getting metal-flake finishes on my eyeballs. Old dog, new tricks...

[Bob Gleason]

I make a lot of dust in my shop, and simple throw covers over my lathe and mill have worked just fine. Living in Hawaii, rust is my enemy!--Bob

[David King]

I have a 9x20 lathe that's been in the shop for 25 years at least. I use the same Vactra #2 way oil as my mill takes and that's been no problem since it's a very thin layer. Wood dust isn't going to affect the ways other than to wick off all the oil so you'll want to keep the oil can handy. I have very effective dust collection on the lathe and that helps keep things clean. Tooling is where you should put your focus. If you're turning aluminum, wood or brass consider investing in carbide inserts and holders along with an indexable toolpost. I use the CCGX 21.52 inserts that fit 3/8" square holders which may be too tall to work in a 7" lathe with a micro toolpost. They leave a beautiful surface finish and are very inexpensive at less than $.50 per cutting edge. I don't know if a smaller form factor exists now but it would be easy enough to mill down the 3/8" holders to fit in 5/16" or 1/4" tool post slots if necessary. I'm sure the online fora are full of info on what fits what and how to modify it if it doesn't.
You might also want to set yourself up with an ER collet chuck that matches the spindle through hole. It's not a cheap mod but it assures .0002 total run out which is ever so handy when you need repeatable precision.

[Barry Daniels]

I found a 1/4" tool holder to fit my Taig. I have never used insert tooling before so I am not sure what to do with it. So, the carbide inserts are not used on steel?

[David King]

Barry, There are myriad carbide grades, coatings and geometries for every type of metal and alloy. Inserts like these are highly polished to leave the best possible surface finish and they are very sharp with a fairly steep rake and clearance angles. They do fine with light cuts on mild steel but would quickly lose their edge or self destruct under the pressure of a heavy cut. In wood these cutters do very well if you come in close to your final dimension in the first pass and take a cleanup pass of about .005". Many of the harder woods don't care how sharp the cutter is but stringy soft woods like western maple are a nightmare even with brand-new cutting edges.