Search found 166 matches

by johnfreese
Fri Oct 11, 2019 2:59 pm
Forum: Lathes
Topic: Screwcutting not picking up in the same place
Replies: 19
Views: 393

Re: Screwcutting not picking up in the same place

I have no experience threading with metric leadscrew. I did look up some information in the Nardini lathe. I have the the Imperial version. I looked in the section that applied to the metric version and found there were 5 possible pinions that could be used on the thread chasing dial. One changed th...
by johnfreese
Sat Sep 21, 2019 5:09 pm
Forum: Live Steam
Topic: 7" schedule 40 tube
Replies: 19
Views: 2115

Re: 7" schedule 40 tube

A well driller I knew used 7" OD casing. He was able to buy random lengths with beveled ends cheaper than 6" sch. 40. I think the 7" casing is common in the oil patch.
by johnfreese
Thu Sep 05, 2019 6:08 pm
Forum: General Discussion
Topic: Which end mill to use
Replies: 25
Views: 3273

Re: Which end mill to use

Be careful what coating you order. Some coatings will cause ali to adhere to the cutter. I use uncoated carbide with polished flutes.
by johnfreese
Fri Aug 30, 2019 6:00 pm
Forum: General Discussion
Topic: Re heat treating mild steel
Replies: 18
Views: 2185

Re: Re heat treating mild steel

Roll cages are usually made from 4130 alloy tubing. The tubing is not heat treated but has gained strength due to work hardening in the cold drawing process. Having been through a fire its properties are near the annealed state, the strengthening due to work hardening is lost. Similarly the low carb...
by johnfreese
Sat Aug 24, 2019 3:50 pm
Forum: Milling Machines
Topic: End Mill Sharpening Fixture
Replies: 3
Views: 809

Re: End Mill Sharpening Fixture

Have any of you PolyChoke owners found a manual for it? I have one but haven't used it because of the time it would take to figure out how to use it properly.
by johnfreese
Wed Aug 21, 2019 9:04 pm
Forum: General Discussion
Topic: Electric Arc Engraver
Replies: 8
Views: 1031

Re: Electric Arc Engraver

Measure the voltage between the work lead and the stylus. Then you can make a decision about safety.
by johnfreese
Wed Aug 21, 2019 8:08 pm
Forum: General Discussion
Topic: Who Makes Good Pry Bars?
Replies: 14
Views: 1906

Re: Who Makes Good Pry Bars?

Mayhew and Dasco make good tools. I would probably go with HF pry bars because of price and warranty.
by johnfreese
Fri Aug 02, 2019 6:43 pm
Forum: General Discussion
Topic: How to Make a Patient Lift Roll up to Low Machines?
Replies: 38
Views: 7120

Re: How to Make a Patient Lift Roll up to Low Machines?

I lift my machines with a pinch bar and blocks until I can get my toe-lift jack under it.
by johnfreese
Tue Jul 30, 2019 5:38 pm
Forum: General Discussion
Topic: How to Make a Patient Lift Roll up to Low Machines?
Replies: 38
Views: 7120

Re: How to Make a Patient Lift Roll up to Low Machines?

Put the machine on blocks tall enough the legs of the hoist will clear.
by johnfreese
Sat Jul 27, 2019 5:10 pm
Forum: Welding
Topic: welding a shaft
Replies: 4
Views: 1209

Re: welding a shaft

Make the extension considerably oversized and the need for accurate alignment goes away. Definitely use a V groove.
by johnfreese
Thu Jul 25, 2019 6:21 pm
Forum: Lathes
Topic: Threading without the end groove
Replies: 44
Views: 16176

Re: Threading without the end groove

There are a number of designs for retracting tool holders you can find on the web. I have been wanting to scale up George H Thomas' design to use on a larger lathe. I believe it was in the 60s Snap Tap made a retracting threading holder that used a trip rod to release the tool. One end of the rod wa...
by johnfreese
Fri Jun 28, 2019 12:45 pm
Forum: General Discussion
Topic: Reaming Cast Steel Fittings without a Mill
Replies: 27
Views: 4180

Re: Reaming Cast Steel Fittings without a Mill

The hoe cutters should do well provided you can pilot them on the existing bore. As NP317 sail rigid support is essential.