Member postings for John Reese

David Wilkes in his You Tube videos preferred turning toward the tailstock. He turned some really long slender shafts without chatter.

There was a proposal to build a CO2 pipeline to collect CO2 from the numerous ethanol plants in the midwest US. The intent was to convey the CO2 to a location where the geology was suitable for underground injection. Strangely the environmentalists are violently opposed to it.

A comment on the radius rod (guide rod) method. The rod needs to be parallel with the bed when the cutter is on the spindle axis (centered on the work..

THE END, I hope.

John,

I doubt you will find the repeatability you want using an abrasive belt or disc. The V-block and clamp shown in several posts would work extremely well in a vertical milling machine. Just clamp the v-block to the table. If the v-block is long enough you may be able to fit two parts onto it. In that case you would want two clamps, each being over one part. You should substitute a length of silver steel for the drill bit shown. If the job is done on the mill it would be permissible to have clamps protruding above the work.

Here in Illinois the state subsidizes wind and solar power. The state also subsidizes nuclear power so they can be cost competitive with wind and solar. Madness.

The most common boring head in machine shops seems to be 2" diameter with 1/2" holes for the tool. The boring tools themselves are available in solid HSS or solid carbide as well as the brazed carbide tools commonly sold with the boring heads. The sizes range from near microscopic to about 1/2". The smaller tools will require an adapter sleeve for use in a larger boring head.

My favorite boring head for work is a Tenthset 37. It takes 3/8" tools. As the name implies they can be set in increments of .0001". The Tenthset 50 is similar but a bit larger and takes 1/2" tools. The Tenthset heads are often available on flea bay. Shank size is unimportant. The back of the boring head is threaded 5/8-18 so it is quite easy to make a shank to fit it.

Flea bay is a source of the smaller boring tools I mentioned.

If you are having difficulty finding silicon carbide mounted points try MSC Industrial. I believe they sell in the UK.

Be careful with long or heavy stones. If run above their critical speed the shank is likely to bend about 90 deg. just beyond the collet. I had it happen on a Dumore (37K rpm) and a Makita (24K rpm). Both had a toggle switch on the back end instead of a trigger. It took both hands to control the tool so I couldn't hit the switch. I had to walk away from the wall socket until the cord pulled out.

Most boring tools with brazed carbide tips need to be ground before use. It is necessary to grind the correct clearance on the end and on the side. If your tool did not work well on the smaller holes I suspect insufficient side clearance.

If the plate is galvanized forget the gas axe or plasma. Vaporized zinc or zinc oxide should not be inhaled.

On a DeWalt grinder I purchased the holes in the nut were hexagonal. If I lost the spanner I could use an Allen wrench.

I have owned several European surveying instruments. All but one had a 5/8-11 female thread in the base. The other was a proprietary bayonet connection.

An "on edge" insert will let you thread very close to a shoulder. If you grind your own HSS tools you can grind a tool that lets you thread right up to the shouder.

For a dozen parts special tooling cannot be justified.

Hollow mills are made in the UK. About 52 Pounds for 8mm.

Projection type chasers would allow the die head to cut up to a face.

The hand cut castellations in your photo look fine to me. A little cleanup with needle files and your part will be just as good as the milled version.

A photo would be a great help.

A 1.25 tpi would have a lead of 0.8 inches. My 16" lathe will not cut that coarse a thread. I figure it was a typo

There are also adjustable hollow mills like these:

**LINK**

There are also solid hollow mills with some degree of adjustment. The OD has a slight taper. A ring is pressed on the OD to provide adjustment.

**LINK**

Brown & Sharpe made hollow mills for use on screw machines.

**LINK**