Search found 970 matches

by jpfalt
Mon Jul 23, 2018 8:23 pm
Forum: General Discussion
Topic: Dressing a diamond grinding wheel
Replies: 11
Views: 1511

Re: Dressing a diamond grinding wheel

The aluminum oxide dressing sticks are made for diamond wheel dressing and shaping. You will go through them fairly rapidly, but they are made cheap for just that reason. They work by eroding the binder between the diamond grains and releasing the grains. The dressing stick gives off a lot of grindi...
by jpfalt
Mon Jul 23, 2018 8:13 pm
Forum: General Discussion
Topic: Keyways
Replies: 15
Views: 2517

Re: Keyways

A properly fit woodruff key is set up so the set screw is offset from the center f the key radius. That way the set screw rotates the key in it's pocket so that the set screw and opposite end of the key clamp the hub in place with approximately twice the clamping force of the set screw alone. This m...
by jpfalt
Mon Jul 23, 2018 8:00 pm
Forum: General Discussion
Topic: Spring making, coils folding over... help?
Replies: 7
Views: 863

Re: Spring making, coils folding over... help?

The problem is twisting of the wire before it goes onto the mandrel. You need to make sure the wire is torsion free when it reaches the guide shoe and wraps onto the mandrel.
by jpfalt
Sun Jul 08, 2018 10:21 pm
Forum: General Discussion
Topic: How to Steady Small Parts on Workbench?
Replies: 23
Views: 3497

Re: How to Steady Small Parts on Workbench?

Strangely enough I use a couple of different things on occasion. If it's a plastic or metal part I use a couple of lumps of modelling clay. It holds the part, keeps it in position or alignment and comes off relatively cleanly. If I'm concerned about possibly marking or staining a semi porous or poro...
by jpfalt
Sat Mar 31, 2018 11:20 pm
Forum: General Discussion
Topic: Machining ballscrews
Replies: 20
Views: 1736

Re: Machining ballscrews

You might want to consider drawing the temper on the end of the shaft you are machining. If drawn past purple to gray, the hardness will come down enough to cut fairly easily with standard HSS or carbide tooling. Also, most ballscrews have an exterior surface that is cylindrical and can be held in a...
by jpfalt
Sat Mar 31, 2018 11:04 pm
Forum: General Discussion
Topic: Machinists Level
Replies: 22
Views: 2165

Re: Machinists Level

Having recently priced the vial, that alone is worth the $60. Levelling the base and readjusting the vial is pretty trivial. I'd say go for it.
by jpfalt
Sat Mar 31, 2018 10:57 pm
Forum: General Discussion
Topic: Cam Lobe Staining
Replies: 16
Views: 1359

Re: Cam Lobe Staining

It could well be an area with low lubrication. Those surfaces will run hotter and varnish out the oil on the metal surface. You didn't mention if he was running a non-detergent oil as this will lead to additional varnish buildup.
by jpfalt
Sat Mar 31, 2018 10:50 pm
Forum: General Discussion
Topic: Cast brass for lathe parts?
Replies: 17
Views: 2079

Re: Cast brass for lathe parts?

It would be better to use bronze for wear contact surfaces as brass wears faster and galls worse than a lubricated bronze. There are a lot of different bronze alloys. Bearing bronze is readily available in scrap plain bearings and casts well. You may also be able to get bronze valve bodies. The easi...
by jpfalt
Sat Mar 31, 2018 10:42 pm
Forum: General Discussion
Topic: Beryllium copper
Replies: 10
Views: 1223

Re: Beryllium copper

I went through this years ago in a machine shop where I was working. I started with the MSDS. In bulk form, beryllium copper is non toxic provided you wash your hands after handling. Welding fumes are hazardous due to the beryllium Inhallation or ingestion of beryllium dust is considered a carcinoge...
by jpfalt
Wed Dec 13, 2017 4:40 pm
Forum: General Discussion
Topic: Learned something about drilling today
Replies: 26
Views: 2496

Re: Learned something about drilling today

Concerning the prick punch, I learned to scribe two intersecting lines at the hole location. Then you place a prick punch tip in one of the scribe lines and follow the scribe like a phonograph record groove until the tip drops into the intersecting scribe line. You can feel it. Then you hit with a h...
by jpfalt
Wed Dec 13, 2017 4:25 pm
Forum: General Discussion
Topic: Elf in the shop
Replies: 41
Views: 3416

Re: Elf in the shop

Also known as the "Snitch-in-a-Ditch".
by jpfalt
Wed Dec 13, 2017 4:22 pm
Forum: General Discussion
Topic: Brass v.s. Bronze?
Replies: 13
Views: 1633

Re: Brass v.s. Bronze?

Use the bronze. Generally speaking, the worst bronze is better than the best brass.