Search found 439 matches

by Conrad_R_Hoffman
Mon Dec 18, 2023 12:48 pm
Forum: Lathes
Topic: Cylindrical Grinding
Replies: 6
Views: 10874

Re: Cylindrical Grinding

And, if your Dumore is anything like mine, wear hearing protection! Mine sounds like a vacuum cleaner on steroids.
by Conrad_R_Hoffman
Mon Dec 11, 2023 1:05 pm
Forum: Lathes
Topic: Logan 200 Headstock Bearing Question
Replies: 3
Views: 8641

Re: Logan 200 Headstock Bearing Question

A 200 should have a double row bearing in the front that you can remove, clean and regrease. I've never tried to remove mine from the spindle, just serviced it while still on the spindle. It should have a common (cheap) single row bearing in the rear that you could clean and regrease, or just buy a ...
by Conrad_R_Hoffman
Tue Feb 28, 2023 4:47 pm
Forum: Lathes
Topic: How to converge to the desired diameter when fitting pieces?
Replies: 24
Views: 14378

Re: How to converge to the desired diameter when fitting pieces?

You have to understand how small the difference is between too-tight and too-loose. With small parts it can be a couple tenths or even less. Combine that with the fact that few people have the ability to measure a bore that well and you can see the problem. Thus the need to sand/polish. 1018 is hard...
by Conrad_R_Hoffman
Wed Nov 30, 2022 2:53 pm
Forum: General Discussion
Topic: Low RPM Diamond Grinder
Replies: 7
Views: 1906

Re: Low RPM Diamond Grinder

Nothing beats an Accufinish slow speed diamond grinder and I suspect you're setup is very close to that, maybe except the wheels. I've sharpened HSS tools on the Accufinish for 20 years and there's no problem with the wheels. I do add some clearance to brazed tools so the soft steel doesn't get grou...
by Conrad_R_Hoffman
Wed Nov 30, 2022 2:48 pm
Forum: General Discussion
Topic: Basic reaming mistake
Replies: 7
Views: 1896

Re: Basic reaming mistake

I'm confused, not an unusual occurrence. I drill and ream using nothing but chucks all the time and never have a problem. Have you checked the runout of your chuck? Reamers are long for a reason. They can deflect a bit to follow the hold, rather than try to redefine the center. Don't chuck them up n...
by Conrad_R_Hoffman
Fri May 13, 2022 1:59 pm
Forum: General Discussion
Topic: Get Material Flat in Vise
Replies: 24
Views: 8746

Re: Get Material Flat in Vise

I had a cheap Kurt copy for some years. Worked OK, but still had the same lift problem. Eventually sold it at a flea market for cheap and bought a Kurt. It's hard to appreciate how much difference the vise can make in your work quality. Depending on what you make, one solution might be to buy a grin...
by Conrad_R_Hoffman
Tue Apr 26, 2022 1:19 pm
Forum: General Discussion
Topic: The digital caliper caper
Replies: 10
Views: 4059

Re: The digital caliper caper

I have those same mics as in the second post and they're extremely good. They'll split tenths with a bit of practice. We use Mitutoyo Digimatic calipers here at work and trust them to about a thou for outside measurements only. Since they don't get used near coolant, they don't seem to get dirty. In...
by Conrad_R_Hoffman
Tue Apr 12, 2022 2:18 pm
Forum: General Discussion
Topic: Smokeless no smell cutting oil?
Replies: 17
Views: 10993

Re: Smokeless no smell cutting oil?

Aervoe Crown Buttercutt is good and they even have it on the shelf at my local Runnings store. I do think Monroe Cool Tool II is a bit more effective. Both will eventually turn dark and degrade. Not sure if rancid is the right word. Cool Tool II will turn brass green if you don't clean it off. Not s...
by Conrad_R_Hoffman
Mon Jan 24, 2022 12:56 pm
Forum: General Discussion
Topic: Need "Rule of Thumb" advice for Oilite bushings.
Replies: 6
Views: 3987

Re: Need "Rule of Thumb" advice for Oilite bushings.

A turntable bearing needs to have very small clearance. It runs at slow speed so getting a proper oil film to avoid metal to metal contact is difficult. IGUS bearings can be great, but the tolerance problem is near to impossible in a one-off situation. I'd do Oilite, but you will have to bore or rea...
by Conrad_R_Hoffman
Fri Nov 05, 2021 11:44 am
Forum: General Discussion
Topic: Drilling small holes
Replies: 25
Views: 11385

Re: Drilling small holes

Just recently I needed some small holes and bought some 0.0085" cobalt drill bits. They were far easier to use than I would have thought and I have little fear of going smaller, if necessary. No doubt I'd snap carbide instantly. Wow! That's really impressive! The machine must have exceptional ...
by Conrad_R_Hoffman
Fri Nov 05, 2021 11:42 am
Forum: General Discussion
Topic: Thin Parts In The Milling Vise
Replies: 22
Views: 13246

Re: Thin Parts In The Milling Vise

I keep a puck of all three varieties of this stuff around- https://aquabondtechnologies.com/home/ Conrad, I looked the website and didn't find any information about how this product is used. Is it just rubbed onto the part to be machined ? Does it adhere as soon as it contacts the substrate ? I've ...
by Conrad_R_Hoffman
Thu Nov 04, 2021 12:48 pm
Forum: General Discussion
Topic: 17-4 ph vrs 303
Replies: 14
Views: 5890

Re: 17-4 ph vrs 303

These guys are our go-to for passivation solutions. Much safer than nitric acid and they make recommendations for just about anything if you call them.
http://citrisurf.com/