Drilling Boring Small Straight Holes

I've decided I need some sizes of tool holders for the Hurco KMB1, that just do not seem to exist. I've looked at various options and employ several of
them, but what I really need is solid one piece tool holders in those sizes. In order to make things a little quicker for setup and tool changes most of them will get extended nose for holding the tools so that small tools with have a similar over all length to larger tools. Among them of course is a handle full of 3/16 and 1/8 with an extended nose. Maybe upto 3/8. To this end I've picked up some "micro" carbide boring bars. Those I have on hand have a 3/16 shaft with a flat to orient the cutting tip.
Anyway, my plan is do everything except back drill the clearance hole in one setup on the modestly ok import 14x40 lathe. The locking color will get machined separately and expanded with heat to be slipped on later. After measuring several commercially made tool holders that part really isn't all that critical. The taper is what accounts for all of the accuracy of the tool.
My query is about the little baby boring bars. The best way to set them up and mount them. I don't have any boring bar holders that small. I almost said "of course," but I've learned when it comes to machining if somebody can think of it somebody has probably already made one. For my larger boring bars I have actual boring bar holders that fit the QCTP on the bigger lathe. Now I do have some tool holders for my QCTP that have a groove in the bottom for a boring bar. I keep a 3/8 boring bar in one all the time. Its pretty handy. I am just wondering if the little tiny 3/16 shank (.120 minimum hole size) micro bars will hold well in that or if they would just get lost. I'll have to cut pretty light since I'll be boring medium hard steel, and I'll be creeping up on a dimensions with a minus pin gage, but I want to get as rigid as possible with such a small tool.
My first thought was that I might have to make a holder for the little boring bars that will fit in the QCTP holder. I'll be drilling and boring modestly deep for that size tool.
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wrote:

Greetings Bob, Holding those small bars in the v grooved will be fine. And the setscrews will locate on the flat to boot. You may run out of height adjustment though. This means you might need to put a little spacer on the tool post for the knurled height adjustment nut to bear against. I do this with no problems. Eric
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wrote in message wrote:

Greetings Bob, Holding those small bars in the v grooved will be fine. And the setscrews will locate on the flat to boot. You may run out of height adjustment though. This means you might need to put a little spacer on the tool post for the knurled height adjustment nut to bear against. I do this with no problems. Eric
******* Thanks Eric, Per Jim's comment as long as I load them up over the tool cart and not over the lathe so I don't lose one in the chip pan. LOL.
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Making a holder may be less trouble than fishing a dropped one out of the chip tray. -jsw
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"Jim Wilkins" wrote in message

Making a holder may be less trouble than fishing a dropped one out of the chip tray. -jsw
****** HA! I had not thought of that. I have lost parts in the chip tray. A couple times it was faster to make another part than to look for the first one.
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wrote:

Or fab a rake so you can empty the tray more often?
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IIRC you don't have a lathe.
I keep a baking tray under the spindle so I can easily dump the chips, but they are miserable to sort through to find small dropped parts, being oily, sharp and in all sizes.
- - - - - This is an inexpensive and useful 30V 5A DC Wattmeter that you can open non-destructively to solder test leads to the USB power pins. I bought the transparent blue one so the internal case clips would be visible. Other models of the black one may have more USB charging features. (Amazon.com product link shortened)07726823&sr=8-1&keywords0v%2B5A%2Busb%2Btester&th=1
The display shows both milliAmp-hours and Watt-hours for battery capacity testing, although it doesn't work at the voltage of a single Lithium unless the cell has a 5V inverter, such as a cell phone booster. The leads I added let it measure 12V or 24V batteries, or adapt USB devices to external power supplies or test loads.
- - - - - I made simple and effective folding stands for the 100W Grape solar panels from 1/2" EMT cut into two 5' lengths and bent into a Vee with a conduit bender. The cut ends are hinged to the back of the panels. A short piece of 3/4" heater hose serves as the non-skid foot.
-jsw
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wrote:

I made this from an import 5C collet block to hold small boring bars and other round shank tools.
http://www.nedsim.com/share/5CToolholder00.JPG
http://www.nedsim.com/share/5CToolholder01.JPG
--
Ned Simmons

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"Ned Simmons" wrote in message wrote:

I made this from an import 5C collet block to hold small boring bars and other round shank tools.
http://www.nedsim.com/share/5CToolholder00.JPG
http://www.nedsim.com/share/5CToolholder01.JPG
******* That's a nice looking tool Ned.
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wrote:

I'll second that. Wish I could weld like that.
P.S: Apparently, Google and/or Mozilla have issues with Ned. WTH?
Deceptive site ahead (large text on red background)
Firefox blocked this page because it may trick you into doing something dangerous like installing software or revealing personal information like passwords or credit cards.
Advisory provided by Google Safe Browsing.
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On Tue, 21 Nov 2017 17:27:07 -0800, Larry Jaques

Thanks.

I got the same thing after moving to a new web host last week. I don't know why, but I suspect it may have to do with a previous host getting hacked and my email hijacked.
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Ned Simmons

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wrote:

Yeah, I've been through that 3 times now. Bloody bastids. Can't live with them, and can't shoot 'em. 'Tis the pits.
Notify the blackballers and get the new host verified.
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On Tue, 21 Nov 2017 12:54:35 -0700
<snip>

I've haven't sprung for a QCTP yet nor boring bar set...
The boring bar set I was looking at the other day would work in my original holder with something like this:

https://www.youtube.com/watch?v=7WI6bhDrM7c

Rather than using set screws I was thinking of cutting a couple of cross slots in a little from either end. Make it so the two outside setscrews would be able to flex the holder enough to secure the boring bar. The two inside set screws would just hold it. One advantage to rolling your own similar to this is you could make it longer than the TP area. Thus providing extra support, rigidity for more reach from the tool holder/cross slide. The set screws would be necessary for that version.
--
Leon Fisk
Grand Rapids MI/Zone 5b
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wrote:

My first home made boring bit holder was a rod slit lengthwise horizontally and I regretted it for the loss of shear stiffness. Now I make custom tool bit holders from bar stock nearly the height of the QCTP slot. -jsw
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On Wed, 22 Nov 2017 08:39:36 -0500
<snip>

Yeah but other than time you didn't have a lot invested and you learned something :)
I was thinking that an offset hole in rectangular stock might be better. It could give you different heights and/or rigidity depending on how it was installed.
--
Leon Fisk
Grand Rapids MI/Zone 5b
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