Shop Made Boring Head

[xo18thfa]

Another handy tool I’ve always wanted is a small boring head for the lathe or mill. Handy to have, but maybe not worth the investment of purchasing one outright. The plan for this boring head came from the internet somewhere, I don’t remember where I found it. Joe Worthy drew the plan in Feb 2004. It appears to be a community college or trade school student project. If any one recognizes this plan, please help give proper recognition to the designer.

Here’s the plan:

http://1stclass.mylargescale.com/xo18thfa/Boring_Head.pdf

Here’s my finished boring head.

The dovetail blocks are from cast iron. Everything else is steel. The leadscrew is 1/4" x 40 TPI.

The only deviation from the plan is the method to engage the lead screw. Worthy’s plan calls for a threaded block screwed to the front of the shanks to drive the leadscrew. If the block is not machined perfectly, it may cause the leadscrew to bind. Instead I used a piece of 1/4" steel bar “floating” in a slot. Here’s the parts

The driving tab slips in the block during assembly. It floats left/right, up/down to engage the leadscrew.

The method works very well. The leadscrew does not bind at all.

The only “boo-boo” was cutting the dovetail slot a “TT” wide. A strip of .002” brass shim stock appears to fix that. The dovetail gib now tightens without effort.

Time to find a project requiring a bored hole.

2011 appears to be the year of metalshop upgrades. Next on the list is George Thomas’ Universal Pillar Tool.

 

[Maryak]

Beautiful work Bob :bow:

The/an other
Bob

 

[moanaman]

Very well done Bob.

A boring head like that is essential on some jobs.

You have much more satisfaction out of making it than handing over a heap of folding stuff and then wonder if it is OK.

Barry G

 

[krv3000]

well dun from a nuther bob

 

[xo18thfa]

Thanks fellas. Need to order a nice set of boring bars now.

Bob

 

[steamer]

NICE!

I need to make one about 1/2 that size for my Aciera!

Dave

 

[websterz]

Thanks fellas. Need to order a nice set of boring bars now.

Bob

Buy commercially made bars for such a nice shop made head? Bite your tongue!! Get some drill rod and make your own. Or at the very least make some up that take carbide inserts. ;D

 

[xo18thfa]

Buy commercially made bars for such a nice shop made head? Bite your tongue!! Get some drill rod and make your own. Or at the very least make some up that take carbide inserts. ;D

Gosh. Now I need to make a heat treating furnace.

 

[deverett]

Thanks fellas. Need to order a nice set of boring bars now.

Bob

Make your own bars. They are very easy.

All you need is some steel bar to fit the tool holder. Cut a groove at the inboard end so that the grub screw does not burr the bar and prevent you from removing it from the head. On the other end drill/ream a cross hole for a round HSS toolbit and drill/tap perpendicular to that hole for a lock screw. The HSS cutter is ground like a left hand tool. Make bars of various lengths and always use the shortest one to minimise flexing. The cross hole can be at 90 or 45 degrees, depending on whether you will be boring through or blind holes. Better still, make a set of each.

Dave
The Emerald Isle

 

[xo18thfa]

Make your own bars. They are very easy.

All you need is some steel bar to fit the tool holder. Cut a groove at the inboard end so that the grub screw does not burr the bar and prevent you from removing it from the head. On the other end drill/ream a cross hole for a round HSS toolbit and drill/tap perpendicular to that hole for a lock screw. The HSS cutter is ground like a left hand tool. Make bars of various lengths and always use the shortest one to minimise flexing. The cross hole can be at 90 or 45 degrees, depending on whether you will be boring through or blind holes. Better still, make a set of each.

Dave
The Emerald Isle

Thanks Dave. I'll go that route. That style will work fine.

Bob