Thread: Drawbar Tool Removal

Originally Posted by oohsam

I was about to buy a collet set and a collet shank. Are you suggesting that the collet shank I get should be one that can thread into the arbour.

Certainly for milling the arbor should be threaded. The vibration from cutting will soon loosen an arbor just held in using friction (and hope). The draw bar is to provide positive retention so it will not loosen. Remember that you do not have to be a Gorilla when tightening the draw bar. A 10 or 12" spanner is fine for applying the necessary torque.

Michael

Originally Posted by oohsam

Ah yes, got it.
I think I'll go with the threaded shank option.
I was about to buy a collet set and a collet shank. Are you suggesting that the collet shank I get should be one that can thread into the arbour.
Because if so, i'd like to keep all the shanks I get (or tools I get) the same, so they'll be all threaded...

Think of it this way.

Most tools that go in the spindle are made up of 2 pieces. The arbor, which may be tapered both ends (drill chuck arbors in general), tapered one end and threaded the other (generally drill chuck arbors with a Jacobs nose taper) or threaded both ends. Typically a boring head that screws onto an arbor but possibly a collet chuck.

Some tools have an integral shank but we can ignore those for the purposes of this discussion.

Now, arbors are cheap so you don't change the tool over on the arbor, you have an arbor permanently mounted to each tool. This way the damn things stay concentric and anyway getting something off of a Jacobs taper nose is non-trivial. They're meant to stay fixed.

So for a mill like yours, buy the threaded shank arbors because they hold more securely, then mount the drill chuck etc and leave them alone. A drill chuck arbor will as I've said have to have a Jacobs taper nose that matches the taper in the drill chuck. Some drill chucks are threaded mount but most aren't.

You really only need 2 or 3 shanked tools to start with anyway - an ER32 collet chuck with collets, a drill chuck and maybe a boring head. I'd get the collet chuck and drill chuck ASAP as they're going to do most of what you want. The collet chuck can also hold drill bits and do it very well, but if you're step-drilling out holes it's faster to swap bits in a keyless chuck than it is to swap collets in a collet chuck.

PDW

Originally Posted by PDW

Think of it this way.

Most tools that go in the spindle are made up of 2 pieces. The arbor, which may be tapered both ends (drill chuck arbors in general), tapered one end and threaded the other (generally drill chuck arbors with a Jacobs nose taper) or threaded both ends. Typically a boring head that screws onto an arbor but possibly a collet chuck.

Some tools have an integral shank but we can ignore those for the purposes of this discussion.

Now, arbors are cheap so you don't change the tool over on the arbor, you have an arbor permanently mounted to each tool. This way the damn things stay concentric and anyway getting something off of a Jacobs taper nose is non-trivial. They're meant to stay fixed.

So for a mill like yours, buy the threaded shank arbors because they hold more securely, then mount the drill chuck etc and leave them alone. A drill chuck arbor will as I've said have to have a Jacobs taper nose that matches the taper in the drill chuck. Some drill chucks are threaded mount but most aren't.

You really only need 2 or 3 shanked tools to start with anyway - an ER32 collet chuck with collets, a drill chuck and maybe a boring head. I'd get the collet chuck and drill chuck ASAP as they're going to do most of what you want. The collet chuck can also hold drill bits and do it very well, but if you're step-drilling out holes it's faster to swap bits in a keyless chuck than it is to swap collets in a collet chuck.

PDW

This is excellent information. Thanks PDW.

I'm on it.
In regards to the ER32 Collets, I am buying an MT4 ER32 threaded collet arbor, and an ER32 collet set.
Will all the ER32 collets fit the arbor, or are they specific?

Reason I ask is that I've noticed that most collet sets sets come with an arbor which is MT3, but all MT4 collet sets which come with an arbour are MT40.
So I was going to buy them separate. Like this :

Collet set

http://www.ebay.com/itm/22pcs-set-ER.../3106365795303

Arbor

http://www.ebay.com.au/itm/CNC-Milli...6c87fc4&_uhb=1


Cheers

I bought an mt4 er32 threaded collet chuck and collets from ctc. I made a spanner to fit the bottom of the spindle of the mill as one of the first jobs.Dean

Originally Posted by Oldneweng

I bought an mt4 er32 threaded collet chuck and collets from ctc. I made a spanner to fit the bottom of the spindle of the mill as one of the first jobs.Dean

Nice !

Should I be getting Metric, or imperial collets...or is this a can of worms?

ER collets squeeze down up to 1mm. A full metric set (pretty cheap from ctctools) will cover all the imperial sizes as well as the rational system.

Originally Posted by oohsam

This is excellent information. Thanks PDW.

I'm on it.
In regards to the ER32 Collets, I am buying an MT4 ER32 threaded collet arbor, and an ER32 collet set.
Will all the ER32 collets fit the arbor, or are they specific?

Reason I ask is that I've noticed that most collet sets sets come with an arbor which is MT3, but all MT4 collet sets which come with an arbour are MT40.
So I was going to buy them separate. Like this :

Collet set

http://www.ebay.com/itm/22pcs-set-ER.../3106365795303

Arbor

http://www.ebay.com.au/itm/CNC-Milli...6c87fc4&_uhb=1


Cheers

Think of it this way.

For milling, you need to assemble 4 pieces.

An arbor with taper to match the spindle, threaded for a drawbar.

A collet chuck permanently mounted to the arbor.

This assembly goes in the spindle retained by the drawbar and stays there until you need to use a drill chuck etc on its own arbor.

Now, to actually cut anything you need a cutter which will have a standard shank - metric or inch, it doesn't matter.

The cutter goes in the individual collet of the correct size (they have a 1mm range for ER32) and the collet goes in the collet chuck, held tightly by the nut on the collet chuck.

Now all you need to do is set the spindle speed, depth of cut and chip load per tooth, that last being impossible without a power feed, so here's where you learn to break cutters..... and all these are dependent on what you're cutting. There's a VAST difference between 316 stainless and 6061 aliminium, to give one example.

Rule of thumb: don't make a depth of cut more than half the cutter diameter if you're using the full width of the cutter in something like cold rolled 1020 steel.

PDW

That all makes perfect sense.
maybe i should order a few extra cutters lol i can see myself breaking alot.

I'll probably be working with delrin and aluminum for a while before i even touch steel..

Stick to M2 HSS at a minimum. The drawbar in my mill was not m16 so i had to make one to fit the collet chuck. I used the same size hex head so i only need the 1 spanner. I need to make a soft hammer/socket combo, like i keep seeing on the net. Doubleboost tells the story about his every time he uses it.Dean

Yes Dean, they are very useful, I made one some time ago.

https://www.woodworkforums.com/f65/combination-drawbar-tool-108330

Originally Posted by Big Shed

Yes Dean, they are very useful, I made one some time ago.

https://www.woodworkforums.com/f65/combination-drawbar-tool-108330

That is a lovely looking tool.

Did you cut the socket out on the Mill?


Cheers

No, nothing clever like that, it is an existing 18mm socket fitted in a hole I turned in the end of the brass.

Still using today, but the hammer end of the brass looks a bit the worse for wear.

I use this tool a lot, not only on my drawbar on the mill (no longer need a drawbar on the lathe as I don't use the ER/MT3 chuck anymore).

Originally Posted by oohsam

That all makes perfect sense.
maybe i should order a few extra cutters lol i can see myself breaking alot.

I'll probably be working with delrin and aluminum for a while before i even touch steel..

Aluminium is very forgiving. Try to get 6061-T6 grade if possible as it machines beautifully. Some of the 2000 series are quite gummy.

Delrin tends to melt so you need very sharp cutters and a slow feed with an aggressive cut - so I'm told. I do very little plastic, mainly UHMW (white breadboard stuff). I try to keep the cutters I've used on steel away from plastic.

You can't really go too fast when cutting aluminium so that's one thing less to worry about. Kerosene makes a good lubricant but a few squirts of WD40 will work - just costs more. Smells better though. The lube helps stop chips sticking to the cutter edges.

As others have said HSS is fine, don't go to carbide until you really need to for the harder steels. It's a lot more brittle and will give you no advantage on plastics and aluminium.

PDW