Member postings for John Reese

I hate fractions. I especially hate the foot, inch, fraction dimensions used in architecture or the degree, minute, second measurements in surveying. I convert everything to decimals.

For coarse threads it s best to flank feed the tool. On medium pitches ether flank feed or plunge feed is acceptable. On fine threads plunge feed is preferred.

Definitions:

Plunge feed is feeding with the cross slide.

Flank feed is done with the compound. The compound is set 1/2* or so steeper than the trailing flank of the thread. The idea is to do the major amount of metal with the leading flank of the tool. Th trailing flank takes a very fine cut to prevent steps in the thread form.

Is it possible you are cutting a 1.25mm pitch? 1.25 tpi is an extremely coarse thread, not one I would expect in model engineering?

Hollow mills are available. Here s an example:

**LINK**

Die heads like Geometric, Coventry, Landis, etc can be equipped with chasers that function like a hollow mill.

Hollow mills are available. Here s an example:

**LINK**

I favor Kurt vise clones. The Arc Euro vise advocated by Steviegtr is a particularly useful clone of the Kurt. It can be set on its side for holding work vertically.

+1 on clipper lacing. It is probably the most compact of all the metallic lacing products. It does require a tool for installation The simplest tool is used with a bench vise.

Have you considered a water pump bearing? **LINK**

My preference is to purchase taps and dies when needed. I select either spiral flute or spiral point depending on whether a blind hole or a through hole. I buy my taps and dies from an industrial supply house instead of a dealer who caters to the hobby trade. That gives me access to a greater range of taps and better quality taps.

I never understood the reluctance by so many to grind a tool bit. A bench grinder and stones or diamond files honing are all that is required and, of course, lots of patience.

I have been advised never to use oil on the plunger. Instead use a solvent like mineral spirits (naptha) to loosen the congealed oil that is causing the plunger to bind.

It works similar to the Dardelet thread introduced in the 1930s.

Here is a surface finish calculator for those who dislike doing the math:

**LINK**

Here is the formula:

**LINK**

There is a definite relationship between feed rate, tool nose radius, and quality of finish. I don't have the formula because one of the apps on my cell phone does the math. I suspect Machinery's Handbook or the European equivalent will show the formula.

Chuck the spindle of the tapping guide in an electric drill. While spinning t in the drill use your bench grinder to reduce the OD.

I have two bench vises with swivel bases I have never used the swivels.

Joe Pie (You Tube) makes knurled knobs that fit the shank of the tap and are held on with a grub screw.

I think a better description would be excess flow shutoff.

Consider an electric die grinder. I only uses 1/2 hp while a pneumatic tool is going to draw the full 2.5 hp of your compressor. Pneumatic is very inefficient.

Universal dividing heads had a shaft geared to the hollow shaft that carreis the dividing pates. It could be geared to the table leadscrew for milling helices. In some cases it could be geared to the spindle to enable divisions that were not possible with the index plates alone. That is the only pace I would expect a bevel gear.