Search found 970 matches

by jpfalt
Wed Dec 13, 2017 4:15 pm
Forum: General Discussion
Topic: Can hardened steel work-harden?
Replies: 2
Views: 1612

Re: Can hardened steel work-harden?

Hardened steel can work harden in addition to being heat treated for hardness. Work hardening is the mechanical addition of dislocations in the metal crystals. The dislocations are places where the crystal structure is distorted so the planes of atoms in the metal crystals don't line up the way they...
by jpfalt
Wed Dec 13, 2017 4:04 pm
Forum: General Discussion
Topic: Learned something about drilling today
Replies: 26
Views: 10481

Re: Learned something about drilling today

Many of the machining texts I used when in high school showed using a center drill as the start of a precisely located drilled hole. They also showed using a cape chisle to relieve the side of a center drilled hole if the center drill was mislocated. Relieving the side of the center drilled hole was...
by jpfalt
Sun Oct 30, 2016 11:25 am
Forum: General Discussion
Topic: Diamond Hone Block
Replies: 20
Views: 7436

Re: Diamond Hone Block

It's HF and considering the punching on the faces, flatness is not really a consideration. If you want flat, dissolve the adhesive with tolulene or such and reglue to a new base with epoxy. Put the hone sheet metal face down on a flat surface, apply epoxy on the backside and place a new base on the ...
by jpfalt
Sat Oct 29, 2016 9:45 pm
Forum: General Discussion
Topic: Diamond Hone Block
Replies: 20
Views: 7436

Re: Diamond Hone Block

BTW, I found the noise from honing on the 4 sided block to be annoying, so I drilled a hole in the end and filled it with grout. The block feels more substantial and is much quieter to use.
by jpfalt
Sat Oct 29, 2016 9:41 pm
Forum: General Discussion
Topic: Diamond Hone Block
Replies: 20
Views: 7436

Re: Diamond Hone Block

The 4 sided hone is supposed to be plated 3 layers deep. I use on frequently and don't use much more than water as lubricant. It seems to hold up better than most hones. The loss of cutting after a few minutes is usually due to swarf plugging up the open face. Clean it with WD40 and switch to water....
by jpfalt
Sat Oct 01, 2016 10:24 pm
Forum: General Discussion
Topic: Burning endmills
Replies: 7
Views: 3261

Re: Burning endmills

You need to reduce the rpms and increase the feed rate. The wood is springy and a low feed per tooth will just rub across the wood surface and make lots of heat. I use a variable speed router on a Shark and usually go down to about 7500 rpm for hardwood at about 50ipm.
by jpfalt
Wed Sep 07, 2016 11:37 pm
Forum: Live Steam
Topic: Equalizer Fulcrum Machining Help
Replies: 20
Views: 17216

Re: Equalizer Fulcrum Machining Help

This is the cutter I use for the type of work you are doing. It's a shell mill arbor with a spacer and collar to mount a slotting saw.
by jpfalt
Sat Sep 03, 2016 12:10 am
Forum: The Junk Drawer
Topic: Weed/ brush hacker head
Replies: 16
Views: 7798

Re: Weed/ brush hacker head

Here's a better picture of the head and a better price. I have no affiliation with the seller.

http://www.partstree.com/parts/shindaiw ... line-head/
by jpfalt
Fri Sep 02, 2016 11:58 pm
Forum: The Junk Drawer
Topic: Weed/ brush hacker head
Replies: 16
Views: 7798

Re: Weed/ brush hacker head

The new engines are usually designed to run a 50:1 fuel to oil mix. I prefer to run Sea Foam instead of StaBil. At the end of the season we always advised to drain the tank, start the engine and run til the engine dies. Then put a couple of drops of engine oil into the spark plug hole and pull the e...
by jpfalt
Fri Sep 02, 2016 11:32 pm
Forum: Live Steam
Topic: Equalizer Fulcrum Machining Help
Replies: 20
Views: 17216

Re: Equalizer Fulcrum Machining Help

I would suggest making up either a stub arbor that you can mount a 4" diameter or larger slotting cutter and take the slots in steps or make up a fly cutter that will extend a lathe tool bit out far enough to cut the slot. The part would start laying on it's back for cuts on one slot and then f...
by jpfalt
Thu Sep 01, 2016 9:17 pm
Forum: Casting & Foundry Work
Topic: Annealing cast iron bar stock
Replies: 15
Views: 19795

Re: Annealing cast iron bar stock

The standard recipe for malleable iron is to pour gray cast iron into a steel mold to get white cast iron and then anneal. When you anneal white cast iron, the carbon precipitates in globs, rather than sheets and flakes. You won't be able to get back to gray cast iron unless you remelt the iron and ...
by jpfalt
Thu Sep 01, 2016 9:12 pm
Forum: The Junk Drawer
Topic: Weed/ brush hacker head
Replies: 16
Views: 7798

Re: Weed/ brush hacker head

I designed those type of heads for several years. For what you're doing, nothing beats a fixed line head. Our most successful was an aluminum cup with holes in opposite sides of the head. End users would take a 20" piece of line, tie a knot in the middle and thread the lines out the opposite si...