Tool block above center

pmhayden

pmhayden

Registered
Registered
Joined
Nov 12, 2012
Messages
16
I have a Central Machine 3 in 1. The tool block holds the carbide tools slightly above lathe center. It is one of the 4 way rotating blocks that came with the (used) machine. Is it possible to disassemble the tool holder, remove a little bit of the base, and if so, should the cutters be centered or a little below center? Or is this normal and I need to deal with it another way?

Btw, I am strictly an amateur. This may or may not make sense. But someone must have had the same problem. Thanks for any help.
 
Last edited:
pmhayden said:
I have a Central Machine 3 in 1. The tool block holds the carbide tools slightly above lathe center. It is one of the 4 way rotating blocks that came with the (used) machine. Is it possible to disassemble the tool holder, remove a little bit of the base, and if so, should the cutters be centered or a little below center? Or is this normal and I need to deal with it another way?

Btw, I am strictly an amateur. This may or may not make sense. But someone must have had the same problem. Thanks for any help.
Click to expand...

Hello, it may be that the tools are a little big for the tool post, if it's just a touch then maybe gringing a little of the tools bottom would be good, only sujesting that as if you mess up the tool holder it will be most annoying, also i'm trying to figure out how you could machine the base down a little with no tool post attached ;-)

if you could hold the tools another way temporaroly you could mount the tool holder in a four jaw chuck and face the bottom off a bit?

have you a picture of how above centre you end up ?

Stuart

ps if you need a pic of a way to hold tools with no tool post let me know ;-)
 
Smaller machine doesn't benefit from tools that are too large. I'd favor getting smaller tools and using shims if needed to get back up to center. Modding the machine is a second choice.....distant second, but that's my opinion only. Modding the tools would be preferable to modding the machine, and I'm counting the toolpost as part of the machine. If you are using brazed carbide, your tooling will cost less if you go smaller, as well as HSS, plus be easier to grind. You can make offset holders for boring bars easily enough.
 
I have a HF 7x10 as well, if you have 3/8" carbide tools, they are slightly high, the simplest solution is to grind bottom of the tool slightly until you get to the right height, if you grind too far, you just have to shim the tool. That way the tool holder is still at the right height for the standard 5/16" tooling. If you start to grind your own HSS tooling, 3/8 blanks are cheap and you just grind the cutting tip to the right height for your machine. A lot less work than modding the toolpost. Besides, you'll probably be dreaming of a quick-change anyway.....
 
Jono said:
Would be easier to pack up the toolpost with shims, then mill with end mill in the spindle, Shims and end mill diameter obviously need careful choice to get right depth of cut.

If your 3 jaw isn't too bad, hold the cutter in that, otherwise, true it in 4 jaw, collet or make or buy end mill holder.
Click to expand...

That does sound simpler :)

Stuart
 
Ok - you say that you have a 3 in 1 - I assume that is the lathe / mill combination. If the tools you have are the kind with replaceable inserts, you probably don't want to modify them. You could do a couple of things. You could take a little off the bottom of the tool post by clamping it upside down in the vise and use an end mill to take a little off the bottom - try to make sure you get it square in the vise, if you want to do this. A couple other options would be to mill a little off the bottom edge of all four tool positions or you might just want to go ahead and replace the toolpost with a Quick Change Tool post. If you go that route, make sure you get the right size for your machine. That last option would give you a lot more versatility - you would have to make it fit the machine - I'm guessing you have a stud that is screwed into the top of the milling vise jaw or something similar. I'm guessing an AXA or 100 size tool post would be the right size. CDCO has an AXA size set for $83 and BXA size for $90 (piston type - wedge type are a little higher). Probably an upgrade that you would want to make anyway at some point. Just another option. A photo would help us all get a better idea of the best approach.
 
Thank you. It is a CM 44132, which is similar to a G9729 I appreciate the replies. I think I will look on to the QC tool post. That way I can let it go for now. I am learning slowly. Making knobs for my kitchen cupboards for starters, just to learn to make chips. And because a friend who does production work gave me a box of 3 inch stainless end pieces off round stock, so I have the steel. I know it's strictly amateur stuff, but I figured it was a good place to start. But I have to cut them off stock at some point. I am wedging the back of the parting tool holder at present to lower the other end. But it is not a permanent solution.
 
pmhayden said:
I have a Central Machine 3 in 1. The tool block holds the carbide tools slightly above lathe center. It is one of the 4 way rotating blocks that came with the (used) machine. Is it possible to disassemble the tool holder, remove a little bit of the base, and if so, should the cutters be centered or a little below center? Or is this normal and I need to deal with it another way?

Btw, I am strictly an amateur. This may or may not make sense. But someone must have had the same problem. Thanks for any help.
Click to expand...
Why don't you just make a semi quickchange tool post like in the attached link? Its simple, it works and for the home shop, what else do you need?
http://www.homemetalshopclub.org/projects/toolpost/toolpost.html
 
Using a QCTP will sooo much easier since tool height can be adjusted on it
 
You must log in or register to reply here.
Back
Top