small boring bar holder

[Frank S]

I needed a holder for a 3/8" shank boring bar. The logical choice was a scrap cemented cutter by drilling a hole in the end to the depth of length of the boring bar shank, then cross drilling and tapping for a standard 3/8" flat point grub screw

I can always silver solder a new carbide on the 5/8" square

[NortonDommi]

Hello Frank,
I found that old injector needles in the 9 litre and up sizes make great small boring bars in a holder similar to yours. Very good quality steel with Vanadium, Chromium and Molybdenum among the ingredients. Takes a mirror polish and hones razor sharp. They make excellent trepanning tools as well.

[metric_taper]

Hello Frank,
I found that old injector needles in the 9 litre and up sizes make great small boring bars in a holder similar to yours. Very good quality steel with Vanadium, Chromium and Molybdenum among the ingredients. Takes a mirror polish and hones razor sharp. They make excellent trepanning tools as well.

From your 9 liter reference I'm thinking this is some sort of llarge engine injector. But I have no clue what this injector needle is.

[DIYer]

Thanks Frank S! We've added your Boring Bar Holder to our Machining category,
as well as to your builder page: Frank S's Homemade Tools. Your receipt:

Boring Bar Holder by Frank S

tags: holder, boring bar

[NortonDommi]

From your 9 liter reference I'm thinking this is some sort of large engine injector. But I have no clue what this injector needle is.

You are correct. Diesel engine fuel injectors have a 'needle' inside the nozzles. When fuel is supplied to the injector pressure upon a land on the needle lifts it off its seat and allows fuel to flow in some designs, others can be electrically operated.
The needles are made of a high alloy steel that makes excellent tools such as small punches, lathe tools, scribes, gravers etc.

If you visit a fuel shop or maybe a heavy equipment workshop, truck shop they often have a pile of old nozzles in a scrap bin. For a small donation to the social club you can usually get a good supply.

[NortonDommi]

The bodies would make a good blade if you are into forging cutlery.

[metric_taper]

This is what I made with a scrap brazed tool bit.

Really tough to throw away good steel stock material.

[Frank S]

This is what I made with a scrap brazed tool bit.

Really tough to throw away good steel stock material.

Yep there are a number of uses for them
I sometimes use old ones as sacrificial blocks

[Toolmaker51]

I needed a holder for a 3/8" shank boring bar. The logical choice was a scrap cemented cutter by drilling a hole in the end to the depth of length of the boring bar shank, then cross drilling and tapping for a standard 3/8" flat point grub screw

I can always silver solder a new carbide on the 5/8" square

3/8"? 5/8"?
Didn't think Frank S had ANYTHING so small...

Meanwhile, anything dual duty is a plus.

[Frank S]

3/8"? 5/8"?
Didn't think Frank S had ANYTHING so small...

Meanwhile, anything dual duty is a plus.

On those rare occasions I do need to bore things small than 0.500 Its at those times that I can appreciate 1 of my 2 small 12x36 lathes
I have just about managed to get my 1956 Sheldon 12x36 tightened and trued up enough to be a halfway decent toolroom lathe. I still want to do away with the 8speed belt drive with the 1 1/2 HP motor for a 5 HP 3 ph motor that I have and a 3ph VFD I figure by going to 5HP even at the slower speeds it should still have sufficient torque if not then I will incorporate a 3 or 4 sp transmission from a riding lawn mower