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Post by cardiffpat on Jan 14, 2007 18:16:10 GMT
I was browsing through the Chronos online catalogue & was interested to see an ER25 collet holder for the mini-lathes.
It had a body with a flange & 4 holes to fit the lathe spindle plate, but surely you would get much better concentricity by using the morse taper in the spindle?, I would have thought that one would get runout by bolting the thing on & off.
I spluttered coffee all over my keyboard when I saw the price of £129.50 for a simple fitting, the only difficult bit to make would be the eccentric self release flange on the nut.
I recall having an issue of MEW which ran an article on making ER collet hoders but I've got a horrible feeling that someone threw it out, anyone know which issue that was?.
I think £130 is serious money for a collet holder (that's putting it politely) for something I can make myself & I'm sure my version will use the morse taper, I'd like to buy the nut though if they sell them.
Any advice on making the collet holders would be much appreciated as I can find no reference to it on google.
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SteveW
Elder Statesman
Posts: 1,399
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Post by SteveW on Jan 15, 2007 0:34:47 GMT
Pat,
A year or so back Warco did (maybe still do) an ER32 (a bit more useful than ER25) Collete holder but it needed a back plate to fit anything. I bought one plus a Myford type back plate. I already had an ER32/R8 set/holder for the milling machine ready for the cheap(er) non-clarkson all TC tooling from JB Tools.
After a bit of simple whittling on the backplate I now have a Collete system that goes from about 2mm up to 20mm. So far the repeatability looks OK, certainly better than the chuck and it grabs all round.
The ER32 set plus holder came from one of Chronos' offers. Adding the bit from Warco made it all the better for the lathe.
I did look at the DIY approach, even had a go but that internal Myford thread but it got the better of me. I made a Myford nose for a test piece but could never get a good internal thread. I finally reasoned that at around fifty quid I could swallow my pride and buy one that was loads better and just put the work done to date down to experience. On getting concentricity the adapter shown in EiM will have exactly the same problems as what I have now having bought a backplate and the ER 23 Collete.
Ultimately it's your choice, bend over and pay the money or spend your life trying to make a decent one. Don't forget that if you want to make one you've also got to make the closing ring. Also, the bought one is a bit hardened.
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Post by Deleted on Jan 15, 2007 7:59:23 GMT
I've just bought an ER32 collet chuck that screws straight onto the Myford spindle for £49.50 + delivery. RDG Tools are the suppliers: www.rdgtools.co.uk an excellent supplier, highly recommended in my experience. |
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Post by Laurie_B on Jan 15, 2007 11:59:12 GMT
I think £130 is serious money for a collet holder (that's putting it politely) Nah!  That's quite cheap actually,compared to the collet set/holder I bought from Arrand Engineering a year or so ago.It cost well over £200,but is an example of quality,precision British engineering-essential to a collet set,I'd say. The one I bought is designed to fit a Myford lathe-it screws directly onto the mandrel nose/register.I also have a 2MT/Myford adaptor which allows the set to be used with,say,a rotary table. Of all the various bits and pieces I've bought over the years,this collet set has been one of the best purchases I've made.A real time saver. I know there a lot of similar,cheaper,imported products on the market,and having bought a few 'imported' items in the past,I find some of this stuff a bit lacking.Cheap it may be in the first instance but quality items will last a long time,otherwise it can be a bit of a false economy. |
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Myford Matt
Statesman
There are two ways to run a railway, the Great Western way, and the wrong way.
Posts: 621
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Post by Myford Matt on Jan 15, 2007 16:32:18 GMT
Spot on Laurie - I bought the very same item and it is of impressively high quality. They don't make the collets, sadly not economic any more.
Arrand are pricey, but you know you are getting real quality.
MM
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Post by cardiffpat on Jan 15, 2007 22:59:56 GMT
I found that issue of MEW with the article on making ER collet holders, No 104, Feb/ March 2005.
I don't see the point of buying a highly expensive holder to fit to a cheap lathe, it's all a question of balance (moneywise).
Anyway it will be interesting to see the degree of concentricity I can get compared to the 'professional' product, might even go as far as case hardening.
Nothing wrong with the top notch gear if you're going to fit it to top notch equipment though.
Regards Pat
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That's quite cheap actually,compared to the collet set/holder I bought from Arrand Engineering a year or so ago.It cost well over £200,but is an example of quality,precision British engineering-essential to a collet set,I'd say.