Long Boring Head

[Canobi]

Hi folks

So my workshop is finally equipped enough to get a start on making the things I put it together for. Unfortunately, my small lathe's toolpost won't take boring bars with the kind of girth I'd like, so I opted to make a long boring head I can use in my ER32 collet chucks:



The head is nothing special and was a simple turning job, though the finish on the head might make one or two of you wince a little but was done on purpose for artistic flair. I'veworks copper and did a fair amount of smithing in my youth and surface texture has always been an interest of mine. It occured to me while turning the head that it wasn't a critical surface so thought I'd see what controlled chatter could do. Though it's a bit uneven as I was testing it out for the first time.


Canobi

[Pa1963]

I prefer girth over length myself, also.

[Loose Ctrl]

This thread is boring.

[Toolmaker51]

You'll wind up with a lot of these. Most used are thru-hole as what you present here, along with flat bottom, and recessing. With correct bits they'll do more than bore; threading, snap and O-ring grooves, undercutting, etc.

[DIYer]

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

Long Boring Bar by Canobi

tags: boring bar

[Canobi]

You'll wind up with a lot of these. Most used are thru-hole as what you present here, along with flat bottom, and recessing. With correct bits they'll do more than bore; threading, snap and O-ring grooves, undercutting, etc.

I hadn't considered using one for those operations, thanks for the tip

[Canobi]

Hi folks

I finally gave the tool a good test run. I used it to cut a radial slot in a part for my next build project (a keyway slotting attachment). I ground a new egde on the other side of the bit too as the original profile is far more suited to cutting internal grooves (as mentioned by toolmaker51).

The new profile needed a regrind, my initial tast was on aluminium and it worked amazingly but the radii was too big for steel. It also took me a while to find the right feed n speed for the tool. I was treating it like a fly cutter at first and had been cranking the carriage leadscrew by hand, being that it only has one tooth but discovered I've actually made a real metal munching monster, which is only limited by my small lathes meagre capability.

New profile prior to regrind:


Initial test cut in alu: