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View Full Version : What Collet Chuck have I got?



irving2008
12-11-2008, 09:10 PM
As the title says, I have a collet chuck that came with the mill... but I have no idea what sort. Its MT3 taper, can handle anything up to 0.7" (17.7mm) through the nut and the internal opening for the collet in the main body is 22.4mm at the top. The nut is about a 32mm thread. The outer dimensions are 48mm dia and from the top of the nut to the gauge line is 66mm....

Ideas?

Robin Hewitt
13-11-2008, 12:03 PM
I got a screwed shank milling cutter imperial collet set with mine. I keep a handy reduced shank 3/4" cutter in it, but for everyday I use ER32, cheap and convenient.

Quick reply, still a distinct lack of smileys. glum

fisherjim
16-11-2008, 07:34 PM
Could be a Clarkson, does it take standard end mills?. Is there a pointed dimple inside the body at the top?.

irving2008
17-11-2008, 12:26 AM
Could be a Clarkson, does it take standard end mills?. Is there a pointed dimple inside the body at the top?.

Yes, there's something that looks like a little centre in there.., here are some pics...

Robin Hewitt
17-11-2008, 12:51 AM
Yes, there's something that looks like a little centre in there.., here are some pics...

That's the one...

Screw the nose shut, it doesn't grip until the cutter is in place. Screw in a milling cutter until it hits the pin, open the nose slightly so you can screw the cutter in another quarter turn then tighten the nose.

Don't screw the cutter in too far, smaller sizes can shatter if not supported by the threads because the nut drives against them.

irving2008
17-11-2008, 07:20 AM
That's the one...

Screw the nose shut, it doesn't grip until the cutter is in place. Screw in a milling cutter until it hits the pin, open the nose slightly so you can screw the cutter in another quarter turn then tighten the nose.

Don't screw the cutter in too far, smaller sizes can shatter if not supported by the threads because the nut drives against them.
Hmmm, I dont understand - what does the cutter 'screw' onto, there's no thread as such inside...

Ah - I see... its a Clarkson Posilock.. uses threaded tanged collets... so I need to buy a set of collets at 35 then some special threaded endmills at 5 - 8 a go...

Should I maybe just go get an ER25 or ER32 collet set...?

Robin Hewitt
17-11-2008, 10:25 AM
Ah - I see... its a Clarkson Posilock.. uses threaded tanged collets...

So you didn't get the wooden box with chuck, spanner and set of four Imperial collets then?

No great loss, compared to the ER32 I now use, it's a piece of dung. Millling cutters from yesteryear only.

I tried inserting a bolt in the back of the 1/4" collet to give it something to press against so I could use an unthreaded cutter, but it didn't have the grip.

irving2008
17-11-2008, 11:00 AM
So you didn't get the wooden box with chuck, spanner and set of four Imperial collets then?

No great loss, compared to the ER32 I now use, it's a piece of dung. Millling cutters from yesteryear only.

I tried inserting a bolt in the back of the 1/4" collet to give it something to press against so I could use an unthreaded cutter, but it didn't have the grip.Thats all the argument I need to go buy an ER32 chuck with collet set from RDG or Chronos...

irving2008
17-11-2008, 11:14 AM
Thinking this through further... my lathe has an MT3 taper also would it make more sense to buy:

ER32 MT3 Collet set

or

MT3 Collet set

Whats the advantage/disadvantage of the direct acting collets?

Robin Hewitt
17-11-2008, 12:36 PM
MT3 collets will reduce the overhang but I don't think they are so keen on intermediate sizes like ER32 which has a much steeper taper and slots from either end. Could be wrong, usually am.

If you go ER32, I prefer the spanner with lots of teeth rather than just one. Can't slip off. Alternatively a long spanner for the top so you can brace it against the column. Just avoid heaving on two spanners at the same time if one of them isn't 100% secure, saves unexpected leaps backwards or heads colliding with milling machines depending on which way you are turning it.

When I started using ER32 I didn't realise you were supposed to hook the collet in to the nose before you put it on the chuck. Nice feature because they eject. Had to break one to find out. :rolleyes:

If you buy ER32 check the run out as soon as it arrives. Run out is part of ER32 spec so if yours exceeds the stated tolerance you can send it back, not as advertised.

Nice to have the whole set, but most of my set are still virgin and untouched. The 7-8mm has lost it's shine along with a few of the smaller sizes. I find CNC usually requires a smaller diameter cutter because my software won't adjust the internal radii to rough out with anything big. I keep a 3/4" reduced shank cutter in that Clarkson for top facing.

irving2008
17-11-2008, 03:54 PM
I could see that MT3 collets would enhance rigidity a little and would allow different length tools to be evened up to reduce the number of times it would be necessary to move the head up and down.

TBH apart from drilling its unlikely I would use a vast range of collets, more than likely could support most milling operations with a limited set of endmills and a facemill/flycutter on the MT3 taper

Will think on it some more...

Robin Hewitt
17-11-2008, 04:07 PM
You can mill with a drill chuck if it takes a draw bar, perhaps a tiny smear of Loctite 601 on the JT end if you can't be bothered to shrink it on. Missing smileys are getting to be a pain. Angst.

Lee Roberts
17-11-2008, 04:44 PM
Use the "Post Reply" button or the "Go Advanced" button, the box below the thread is a quick reply system. :) :beer:

Robin Hewitt
17-11-2008, 05:03 PM
Pressed post reply, still no smilies GLUM

irving2008
17-11-2008, 07:20 PM
Irving, I just use collets in the MT3 for the simple reason I'm tight....and the next machine has R8 I also like the fact of the overhang being reduced.....And being tight :D


Have you seen the SIP unit on fleabay? Heidenhain DRO (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=270302599814&ssPageName=STRK:MEWA:IT&ih=017)Yes, I've been watching it..

Same as mine :) (ok so there's a lot of tooling I dont have)... So far tho all the ones that have come up on eBay in the last 3 weeks have all been 500++ , so the 365 I paid was a good deal :) (mine has DRO on vertical)

Jeremy
17-11-2008, 08:08 PM
Interesting discussion on ER collets. It led me to look at changing my clunky Clarkson on the home-built Dore Westbury I have, which then led to the discovery of these ER16/20mm milling chucks: http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Collets-Collet-Chucks/ER16-Collets-Collet-Chucks (4th item from the bottom of the page).

The idea that occurred when I spotted this item was to make my own high-speed router spindle, using one of these, a set of decent bearings and a nice, big, RC model electric motor.

Having now ordered one, plus a couple of collets, for use on the new machine it looks like I shall have to soldier on with the old Clarkson in the mill for a while longer..........

Jeremy

PS: No shortage of smilies for me :beer:

Robin Hewitt
18-11-2008, 10:10 PM
There seems to be a glut of smilies here :beer: :beer: :p;)

I've got my smilies back :beer:

Had a rummage through my user CP and found it was switched to 'basic editor' upgraded it and there they are :D

Looking at a mill on ebay today, idly threw in a 500 bid and matched first place.

Then the bidder I was tied with withdrew his bid :confused:

Then he bid 490 :confused:

Hello, thought I, he's playing mind games. So I upped my bid to 750 so now he hasn't got a clue where I am :rolleyes:

It's going to go for a lot more than that so this is all rather academic. I doubt I will get my new mill until this recession really starts to bite :D

Jeremy
18-11-2008, 10:28 PM
Glad you sorted the smilies out, and that it turned out to be something straightforward, if a little obscure!

I got home from work at lunchtime today to find a package from Arc Euro containing my new ER16 collet chuck, collets, etc had arrived. Pretty good service, as I only ordered them yesterday lunchtime. Less than 24 hours from placing the order to arriving on my doorstep seems remarkable.

I'm currently perusing the RC motor web sites looking for a suitable motor. I think I've found one that will be OK and should give me a spindle speed of up to around 30,000 rpm using the spare 12V, 30A, power supply I have. These things are amazing value, I can get a brushless three phase motor rated at around 450 watts or so, complete with a suitably over-rated speed controller, for around 30, including postage.

The current plan is to directly drive the spindle from the motor shaft, using a suitable coupling.

Next hunt is for decent deep groove bearings that will spin at 30,000rpm - methinks I might well be into ceramic ball technology at these speeds.............

Jeremy

irving2008
18-11-2008, 10:37 PM
I've got my smilies back :beer:

Had a rummage through my user CP and found it was switched to 'basic editor' upgraded it and there they are :D

Looking at a mill on ebay today, idly threw in a 500 bid and matched first place.

Then the bidder I was tied with withdrew his bid :confused:

Then he bid 490 :confused:

Hello, thought I, he's playing mind games. So I upped my bid to 750 so now he hasn't got a clue where I am :rolleyes:

It's going to go for a lot more than that so this is all rather academic. I doubt I will get my new mill until this recession really starts to bite :DUnless he reads this! ... so you are bidder 3 then... I agree, it should go for far more, but fleabay is a strange place... nice big table, and DRO but the control unit showing its age... is that c1980s?

There's a nice Bridgeport with DRO just up the road from me going for 265... if only I had the room...

Robin Hewitt
18-11-2008, 11:56 PM
... so you are bidder 3 then...


Ah, you've found me :D

The controller would have to go. I'm still writing RobinCAM but I want it bad. The arc stepping routine just carried across from 'C' to assembler and is doing a healthy 1000 steps per second top whack. Not bad considering it's doing 2 unnecessary 48 bit squares per step on an 8 bit, 6MHz, CPU.

PS: "irving2008 has exceeded their stored private messages quota and cannot accept further messages until they clear some space".

Robin Hewitt
19-11-2008, 12:05 AM
The current plan is to directly drive the spindle from the motor shaft, using a suitable coupling.

Hi Jeremy

What is a suitable coupling for 500 revs/second? :confused:

Balance probably isn't a prime consideration, but no bending parts obviously.

I'd probably go for a rod though one shaft engaging a pair of driving dogs on the other, then spend half an hour adjusting it 'till it ran quiet :D

best

Robin

irving2008
19-11-2008, 12:13 AM
PS: "irving2008 has exceeded their stored private messages quota and cannot accept further messages until they clear some space".sorted that

irving2008
23-11-2008, 08:37 PM
I've got my smilies back :beer:

Had a rummage through my user CP and found it was switched to 'basic editor' upgraded it and there they are :D

Looking at a mill on ebay today, idly threw in a 500 bid and matched first place.

Then the bidder I was tied with withdrew his bid :confused:

Then he bid 490 :confused:

Hello, thought I, he's playing mind games. So I upped my bid to 750 so now he hasn't got a clue where I am :rolleyes:

It's going to go for a lot more than that so this is all rather academic. I doubt I will get my new mill until this recession really starts to bite :Dbet you were getting worried... but in the end it went for a very reasonable 2,260 (but was 1500 with <1min to go).

Picked up a good set of engineers parallels 10 pairs x1/8" for 15 on eBay, a bargain I think.

Have decided to buy MT3 collets and a few other bits... (6" vice, some endmills, etc.), priced up from RDG they come to just over 250... any suggestions where else to check pricing?

irving2008
23-11-2008, 09:55 PM
Try Chronos Irving.....RDG are very good...They ordered me a VA4 vice from Vertex so now I have a matching pair :toot:

P:S If you buy from RDG regularly you'll have a nice collection of rulers :D :beer:Already priced up on Chronos, they are a lot more expensive. I think it is because they include postage in each item's price and that adds up when you buy a lot at one go. And I already have 2 RDG 6" rulers!

Here's my shopping list - what should I add/leave off/change?

11-piece MT3 collet set (need to check drawbar size)
MT3 indexable face mill (need to check drawbar size)
MT3 keyless 1-16mm chuck (1/2" BSW drawbar)
12-piece set of metric end & ball mills
centre drill set
Vertex K6 milling vice
metric tap and die set
1 - 10mm in .1mm HSS drill set

Thats 362 (I added a couple of things!)

Robin Hewitt
23-11-2008, 11:13 PM
I was only slightly dubious because I web searched it and found two interesting thoughts. Some bod in Yankland saying an early 80's refurbed MH-600P was worth about $1500 so my bid was about right. Someone else saying his had crashed and the only thing coming on was the hydraulic motor.

Hydraulic motor :confused:

Also I'm changing units up on the industrial estate. My landlord has plans to turn my shop in to a building site over December and there was another one going that was warmer, drier, better lit and slightly cheaper to boot. I do like my creature comforts but probably best not to buy large milling machines until I've settled in.

I bought my set of ER32 collets and a #40 chuck for under a hundred on fleabay then sold the chuck so I got my collets for just over 70 which was good back then.

irving2008
24-11-2008, 08:41 AM
Ballscrews drivers touchscreen PSU Are you going to keep it manual? if so you need a rotary table....Unless your hand eye co-ordination is amazing :D :beer:No I will CNC it eventually... I suppose boring head and a rotary table are the next things...

I already have a 48v 15A PSU and a 70v 9A one and the drivers I'll make myself... so its just steppers, ballscrews and other bits n bobs I'll need, but they'll have to wait a while...:rolleyes: