Blomquist Lathe Clean-Up

[chester179]

Bought a Blomquist (southbend clone) lathe on ebay last year.
before

and after.

Its my first big lathe and seems to work tolerably well but i dont get a glassy finish turning 303 stainless more like either a very fine matt finish or a shiny mottled finish. I wonder is thats as good as i can expect on a circa 1950s lathe with 3 thou runout on the spindle.

 

[DJP]

I have the identical SB lathe but mine is 1940s version. There is too much wear to expect a fine finish. For SS work I get best results with a carbide insert or carbide tipped tool that has a big radius. I create the radiused cutting tip using a green wheel.

The bigger issue for me is parting off as everything needs to be tightened down and the cut needs to be very close to the chuck.

Old machines still do valuable work so I cherish them even if the final finish isn't super smooth.

By the way, these old machines throw a lot of oil so your nice new paint won't stay clean for long.

It's good to see my old SB being featured in this thread.

 

[DJP]

One more thing to test.... with the carriage close to the chuck, adjust the lock so that there is a noticeable amount for friction as you move the carriage back and forth an inch or two, then crank it all the way back to the tail stock to see where it locks up. It's a good test of how much bed wear you have. Mine doesn't get very far so its previous life must have been a hard one.

 

[chester179]

Thanks for the feedback DJP. Good to know that i can stop obsessing over the lack of perfect finish. Dont tell anyone but when it comes to parting off i just go through it using a hacksaw and then face off.
Ive put up oil protection to catch the most part of the splatter , the new white paint is already wearing through on the handles .
Im still experimenting with hss vs carbide , i do find i get a better result with a style of tool where the cutting edge trails behind the leading edge , i will try changing the radius.
One of the limitations i feel i have is that the max rpm is a little under 1000rpm so without the ability to experiment at higher rpm im always thinking that maybe its the rpm that holding me back.

 

[DJP]

Just following up with a picture of my lathe. It's old but it continues to do good work for me. The other day I cut a left hand thread for a turn buckle. It's a part that you can't easily find but making one was easy.

 

[chester179]

Nice lathe thanks for the pic. For what they cost to buy these days you get a lot of lathe for your money. I paid £100 for mine and everything considered am glad it works as well as it does. Everything polishes up ok with a bit of fine paper.
The turning speed noticeably drops under load on mine so i intend to upgrade the motor from the current 200 watt one to half or 3/4hp , whatever turns up.

 

[DJP]

From your picture I can see that you are running at the middle speed. I keep mine at low speed and with a big heavy chuck and .030 cuts I do not notice the lathe working very hard. I delayed upgrading the motor out of sympathy for the aged components.

I agree that these old machines are great value as mine came with a collection of chucks, tooling and the bench. Still I do envy the guys who are setting up a bigger new lathe. Changing gears for thread cutting is a pain.

Most of my shop is populated with machines from the 1940s and they suit my age too.

Take care