question for those using boring bar heads on your mini metal lathe.

[Fordwakeman]

I have a HF metal lathe (the little red one). I was wondering if I get a mt2 boring bar tool holder, how small of a boring head can I use. do they make micro boring heads that fit in thosetype of holders? I have seen folks who make rings use these. thanks for any information you can provide. i'm wanting to do holes as small as 7mm

 

[FGarbrecht]

I have a couple of micro-sized boring bars, too small for a standard boring bar tool holder. I haven't seen any micro boring tools that fit in the standard holder but that doesn't mean they don't exist. Seems like constructing an appropriately sized ring would be a trivial exercise if you already have the metal lathe, but I just clamp them in a standard QCTP tool holder using 3 of the 4 clamping bolts and works fine for boring in softer materials.

 

[Fordwakeman]

any chance you could tell me what ones you have and where you got them?

 

[Dieseldoc]

All I have done is take 1/2 sq stock , bore hole size of my. special ground boring bar, drill tap sq block to hold bar with two Allen screws. Then use like you do for any sq bar in QC holder.

 

[FGarbrecht]

any chance you could tell me what ones you have and where you got them?

Amazon.com

Search on amazon for 'micro boring bar' and a bunch of them come up

 

[Fordwakeman]

thank you

 

[More4dan]

I've also made a sleeve in the lathe out of aluminum to match the ID of my 3/8"boring bar holder with a hold drilled to match the smaller boring bar. I cut a slit the length of the sleeve on my band saw through to the hole. I can now clamp it into the normal holder and it holds it nice and tight. I use this to hold router bits in the boring bar holder for rounding over the ends of material.

Another option is to start with drill rod the size of your holder and turn it down to the size you need for boring, heat and quench, grind to shape.

 

[Dieseldoc]

I've also made a sleeve in the lathe out of aluminum to match the ID of my 3/8"boring bar holder with a hold drilled to match the smaller boring bar. I cut a slit the length of the sleeve on my band saw through to the hole. I can now clamp it into the normal holder and it holds it nice and tight. I use this to hold router bits in the boring bar holder for rounding over the ends of material.

Another option is to start with drill rod the size of your holder and turn it down to the size you need for boring, heat and quench, grind to shape.

Danny: Good idea to get the job done. My process has worked for me and I sure yours is doing the same.

 

[jalbert]

I basically did the same as @Dieseldoc , but used round stock (as that was all I had), and milled a flat on top to allow a place for the set screws in the tool holder to grab.