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View Full Version : Parting tool -what am I missing?



lakeside53
04-18-2009, 01:30 AM
I have a Phase2 AXA with parting tool holder.

MSC and Emco both say I can use the "T" or beveled parting tools, but.... the tool holder is flat on the support wall. i.e. there is no recess for the top section of the "T" type. The T blade mounts at an angle.

Do I need to put a shim in the lower half at the back of the holder to get the blade vertical?

agrip
04-18-2009, 08:47 AM
In a word - Yes.

The Aloris P/O tool holder, clamps down on the concave face of a T bit, and in turn down on the narrow bottom face.

You can most easily hold them in position by using a shim between the relieved side of the tool and the inside face of the holder, while using finger pressure with one hand and running the clamp wedge screw with the other hand.

Caution - - beware of concave surfaces not being exactly square with sides of the bit, or viceversa. Easy enough to determine before careless crash.

A T bit working properly will give you swarf coils liken to a clock spring.
A lubricating cutting oil will pool in front of the coil.

Ag

quadrod
04-18-2009, 08:53 AM
i just put a feeler gage between the blade and the holder. it sits under the " T " and holds the blade straight

Frank Ford
04-18-2009, 10:28 AM
The Aloris holder has an angled slot, so the "T" shaped parting tool stands upright. I modified my Chinese holders by milling a simple groove to allow clearance for the wide section of the tool:

http://www.frets.com/HomeShopTech/Tooling/CutoffHolder/cutoffholder03.jpg

On the left, my modified Chinese tool, on the right, the Aloris with its angled slot - both hold the T tool upright:

http://www.frets.com/HomeShopTech/Tooling/CutoffHolder/cutoffholder06.jpg

Here's the full project on my Web site:

http://www.frets.com/HomeShopTech/Tooling/CutoffHolder/cutoffholder.html

PaulT
04-18-2009, 10:43 AM
If you are going to have only one carbide tool in your shop, I'd make it a carbide insert cutoff tool, they work way better than the steel blade ones.

And it sounds like your cutoff holder may be intended for one of the carbide cutoff blades as they are totally flat (no T). Its probably setup for a 3/4" tall blade, you can get carbide holders in this size from www.use-enco.com, you'll be after one of the holders that uses a .087" or 0.093" insert.

You can use the C5/C6 inserts both on steel and aluminum/brass, you don't really need to stock both the C2 and C5/6 types, unless you're doing production quantities.

Good luck-

Paul T.

PS - looking at the tool holders in the pictures, it looks like the blade is angled on those. The carbide blades are not meant to be angled as the angle is built into the insert mount, so if your's is angled it unfortunately wouldn't work right with the carbide blade and you'd need to get a new blade holder. I'd still get one anyway, they really work, and for me cutoffs are no longer "white knuckle" experiences.

Frank Ford
04-18-2009, 04:31 PM
I think it's just parallax or other artifact of the photo. Those bits are both very close to vertical in their holders, and they cut equally well.

ftl
04-18-2009, 04:57 PM
I've thought about doing exactly what Frank has done. Lazyness has prevailed however and to date I just put a strip or two of transparent tape on the lower part of the cutoff tool so it sits up straight. It is clamped from the top and bottom so there is really no force on the tape once the holder has been tightened.

I think Frank's technique is the better long term solution.

agrip
04-18-2009, 05:44 PM
I mount mine as far outboard as I can stably get.

Lets me get in really close to chuck jaws and collets.

I also use T blades with different heights and widths.

Ag

Ron of Va
04-18-2009, 06:37 PM
I have used a small drill bit laying down at the bottom to kick out the cutter enough to get it vertical. It worked fine. Then I forget its there and it slips out when I make an adjustment, and I have to go looking for it.:D

lakeside53
04-18-2009, 09:08 PM
Thanks guys... Looks like (finally!) I wasn't missing anything... I'm going to mill a slot.

I also have one of the 26-3 carbide insert parting tools from "pre-axa" but it's 3/4 (AXA takes 1/2). Aloris makes a similar holder, but it's spendy... And.. just looked into my box of stuff.. several 3/4 and 1 inch brazed carbide cut-off tools. I might have to make a holder:D

clutch
04-19-2009, 02:06 AM
Is there an accepted parting tool width to parted item diameter ratio? Assumptions we are parting mild steel.

Thanks,

Clutch