Search found 8 matches

by Herb Kephart
Thu Nov 21, 2019 2:46 pm
Forum: Gunsmithing
Topic: Best choice of steel for color case hardening?
Replies: 10
Views: 7914

Re: Best choice of steel for color case hardening?

Years ago, an "Old Timer" told me to use chicken bone, broken into the smallest pieces possible. Worked rather well, but as time went on I learned that bone is loaded with Phosphors, which makes steel brittle. The brittleness would only be on the surface, but that's where cracks start. Is all this n...
by Herb Kephart
Thu Nov 21, 2019 2:05 pm
Forum: Gunsmithing
Topic: rotary table
Replies: 10
Views: 6837

Re: rotary table

Our 20" Troyke lives on a roller table when not in use. When needed, table rolls over to machine (which ever one) and machine table is adjusted so that heights match. Then rotary is slid across the gap, wiping under side in process.
by Herb Kephart
Wed Mar 27, 2019 8:42 am
Forum: I.C. Engines
Topic: Piston Knurling
Replies: 17
Views: 17984

Re: Piston Knurling

I made a threaded device to go inside a piston skirt (aluminum skirt) that can force more ovality into it, and thereby increase its "size."

Have also made pistons by turning the heads from aluminum bar stock, and heliarc welding skirts on.
by Herb Kephart
Fri May 11, 2018 3:07 pm
Forum: Lathes
Topic: Looking to buy a new Lathe need some advice.
Replies: 16
Views: 6350

Re: Looking to buy a new Lathe need some advice.

I have almost eliminated the "rattle" of cutting teeth completely off gears by mounting two carbide tools, one above the other, and spaced so that one is fully into the cut, while the other is on the space between teeth. These were gears more or less 20" in diameter with 4 DP teeth. A little more th...
by Herb Kephart
Fri May 11, 2018 2:44 pm
Forum: Lathes
Topic: Chuck mounting helper
Replies: 14
Views: 5402

Re: Chuck mounting helper

We have done the same thing as Earlgo on one of the large lathes, the other biggie has a swinging arm post crane with an electric hoist. Another heavy thing to move around is the vise on one of the 16" shapers. A short overhead rail with a hoist picks this up with an eyebolt, screwed into the movabl...
by Herb Kephart
Tue Dec 19, 2017 8:15 pm
Forum: I.C. Engines
Topic: The Duke Engine (VERY COOL)
Replies: 6
Views: 8282

Re: The Duke Engine (VERY COOL)

The downfall of most of these rotary engines is lubrication between the valve plate, and whatever rotates against it. Enough lube to prevent seizure and you get excess oil consumption, if not, seizure eventually occurs. Back on the 60's, I made some prototype parts for the inventor of a variable com...
by Herb Kephart
Mon Apr 10, 2017 9:43 am
Forum: The Junk Drawer
Topic: 2005 Ford power stroke
Replies: 21
Views: 4830

Re: 2005 Ford power stroke

One thing to watch for in that whole series of Internationals-- the IDI 6.9's,7,3's and all the iterations of Powerstroke is the blocks tend to get pinholes in the bores going into the water jackets if the DCA concentration in the coolant isn't maintained. Then it's sleeve time (and also to take out...
by Herb Kephart
Sat Apr 08, 2017 8:32 pm
Forum: I.C. Engines
Topic: Ignition Polarity
Replies: 33
Views: 21755

Re: Ignition Polarity

Month old subject here, but I just joined and am reading a lot of things of interest to me at the site What I used to hear, back when dragster people and the like were the only ones looking for that last little bit that they could get out of an engine, was that the center electrode of the plug, bein...