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Steve Middleton
07-25-2011, 11:21 AM
I purchased a nice Aloris style QCTP from Little Machine shop. Included were 5 tool holders labeled TAR, TAL, TBR, TBL, and TE. I know TE is for threading and R&L mean right and left but can't find anything abt A/B. I'm sure it's simple so please enlighten me:)

DFMiller
07-25-2011, 11:47 AM
Steve,
Not the best description but it gives some details
http://www.practicalmachinist.com/vb/general-archive/indexable-lathe-tool-designations-98347/
Dave

Thomas Staubo
07-25-2011, 01:31 PM
This is what it says on the website:

This set includes the tool post and the following tool holders:
No. 1 - Turning & Facing,
No. 2 - Boring, Turning & Facing,
No. 4 - Heavy Duty Boring,
No. 7 - Universal Parting Blade,
No.10 - Knurling, Facing & Turning.

I cannot see any reference to the designations you wondered about.


.

roundrocktom
07-25-2011, 01:57 PM
I purchased a nice Aloris style QCTP from Little Machine shop. Included were 5 tool holders labeled TAR, TAL, TBR, TBL, and TE. I know TE is for threading and R&L mean right and left but can't find anything abt A/B. I'm sure it's simple so please enlighten me:)

A & B are two different angles.

A is the 90 degree (facing tool).

B is 70 or 80 degrees (cutting tool).

Seems like Machinery Handbook should spell out the angle for "B" - just can not remember it.

roundrocktom
07-25-2011, 02:05 PM
Thomas,

At the bottom of that page Stephen gave is the details:




L's and R's are for left hand and right hand tools. For simplicity, on a typical lathe setup, right hand tools cut moving toward the chuck and lefts cut moving toward the tailstock.

A's have a zero degree side cutting edge angle. So, if an A is set purpendicular to the ways, it turns a square shoulder.

B's have a 15 degree positive lead angle. Positive lead means the corner trails the remainder of the side edge in the direction of cut.

C's are ground straight across the end. I guess you could plunge a big groove with one or maybe cock it sideways a bit and face with it, but I've seen them used as blanks for grinding a form tool more than anything else.

D's have a centered point with an 80* included angle. Looks kinda like a threading tool, but it ain't one.

E's are like D's except the included angle is 60*. Some people refer to them as threading tools, but IMO, it ain't one either

There should be a number too for the tools. Like an AR4 or AR6. The number is the shank size in sixteenths. An AR4 is a quarter inch shank tool.

Added....there should also be a grade designation. C-2's are for aluminum. C5 or C6 is for steel. Another common designation for brazed tools is the old carboloy designations. 370 is for steel, and 883 is for aluminum.

PixMan
07-25-2011, 02:50 PM
Those insert holders also make excellent fishing sinkers, boat anchors, small farm implement chock blocks, spacers,....all kinds of great uses. ;)

Seriously now, watch out for those things. They often come fitted with the wrong style inserts for the pockets, and are often made from a butter-soft steel-like substance covered in a black with a lead & cadmium-filled paint-like coating. The inserts are made from compacted clay, sometimes fired to a glass-like brittleness, sometimes unfired.

There are a few good sets out there, including one made in USA by Micro 100. Even those use a nearly-proprietary and hard-to-get TT-designated insert. You'll find that if you do start using them, you'll use the TAR for 95% of what you do, and the rest collect dust.

At least the QCTP will be useful. Good luck.

Thomas Staubo
07-25-2011, 03:06 PM
Thomas,

At the bottom of that page Stephen gave is the details: Oh, I see now (after a bit of searching). Stephen gave no page as I can see.

I thought he talked about the tool holders (he said so), but it's the indexable turning tools that has those designations.


Stupid me :rolleyes:


.

Steve Middleton
07-26-2011, 12:44 PM
Thanks for the replies. The light comes on a little bit at a time. This seems to be pretty well made. The inserts are carbide and I've already managed to chip a couple thanks to my ignorance:) That's ok, I have a well used HF 8 1/2x18 lathe and newer HF mill for learning purposes. Assuming I'm still learning next year will upgrade as it makes sense.

Boucher
07-27-2011, 07:43 PM
These sets get criticized a lot but they are very useful for light cutting jobs when used with good ceramic inserts.
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0144Small.jpg
These inserts are available from Carbide Depot. With their smaller size it is easier to access some difficult conditions than with the larger more robust tool holders. I find them handy to have.

Steve Middleton
08-01-2011, 09:31 PM
Thanks for all the help. I'm "high centered" at the moment. My new tool post is too tall, waiting for vise and coolant for mill so I can make things line up. So what's preferred to the "carbide inserts" ? HSS?