Stephen Rowley | 14/08/2011 09:56:53 |
57 forum posts 14 photos | Hi all I have a Chester's Micro mill with an MT2 spindle. The chuck that comes with the machine has a bolt which hold it in but the larger chuck I have, end mill and some other bit do not have a screw thread so after 5 min of use they fall out and on two occasions have spoilt my work. Are Morse tapers supposed to hold them selves in? |
ady | 14/08/2011 12:12:17 |
612 forum posts 50 photos | Even if they are, (some tapers may be designed for this) I find that vibration tends to loosen it unless the tool is kept pressed against the work. So drilling is fine but milling would need a drawbar (big long bolt into back of morse taper) to keep it pulled back under tension so you had a "zero risk" system. I would try to make a bolt hole system in the back of the other bits, and that would solve my problems. |
Jeff Dayman | 14/08/2011 13:48:50 |
2356 forum posts 47 photos | If I were you I would get and use only Morse tooling with screw threads in the rear end for use in your mill.
I would also be looking to trade the mill ASAP for one with an R-8 or other milling machine type spindle socket. Maybe Chester have a replacement spindle for your mill with R-8 socket?
Any chatter or unbalanced cutting forces (as many milling ops have) will loosen a Morse taper. Morse is fine on large drills for heavy steady cuts only, or on centres for holding work in lathes. I guess manufacturers put Morse spindles in small mills hoping prospective buyers will think they can use lathe tooling they may already have, but in practice it does not work well unless threaded hole and drawbar are used.
Sorry I don't have better news.
JD |
matt | 14/08/2011 14:00:35 |
24 forum posts | Posted by Jeff Dayman on 14/08/2011 13:48:50: If I were you I would get and use only Morse tooling with screw threads in the rear end for use in your mill. I would also be looking to trade the mill ASAP for one with an R-8 or other milling machine type spindle socket. Maybe Chester have a replacement spindle for your mill with R-8 socket? Any chatter or unbalanced cutting forces (as many milling ops have) will loosen a Morse taper. Morse is fine on large drills for heavy steady cuts only, or on centres for holding work in lathes. I guess manufacturers put Morse spindles in small mills hoping prospective buyers will think they can use lathe tooling they may already have, but in practice it does not work well unless threaded hole and drawbar are used. Sorry I don't have better news. JD
Edited By matt on 14/08/2011 14:02:30 Edited By matt on 14/08/2011 14:04:58 |
Steve Withnell | 14/08/2011 18:45:37 |
![]() 858 forum posts 215 photos | On the Chester site the micro mill is quoted as having a B10 taper - Arceurotrade's is quoted as having a JT1 spindle taper. Which model of machine have you got?
MT2 and MT3 tooling is exceptionally popular, you should have no difficulty in picking up the right bits - Arceurotrade is a good place to look (satisfied customer...) Drawbars - I've used threaded bar from the hardware shp with a nut on the end. Nothing clever here.
Steve
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Oliver Lindley | 14/08/2011 18:54:26 |
13 forum posts 3 photos | I would imagine JSK's mill is a sieg X1 clone - I have one too (the clarke variant). Strangely enough i have just had a similar problem - see the post "Tang type Morse Taper cutter"
I got a tang type cutter off ebay and decided to cut the tang off and weld on an M10 adaptor because it was too hard to drill/tap. I also bought a larger chuck for my mill and i was able to drill and tap the morse taper on that. |
MAC | 14/08/2011 19:02:23 |
68 forum posts | Don't agree that only R8 is acceptable. I'm sure many people, including me, use MT2 and are happy doing so. Yes, one day I'd like a Bridgeport - but for now I am more than happy with my MT2 equipped Mill and the work it produces. |
JasonB | 14/08/2011 19:25:27 |
![]() 25215 forum posts 3105 photos 1 articles | "I guess manufacturers put Morse spindles in small mills hoping prospective buyers will think they can use lathe tooling they may already have, but in practice it does not work well unless threaded hole and drawbar are used."
Given that a lot of people would have had MT tooling that they used in the spindle of their lathe such as Slitting saw holders, flycutters, ER chucks, mill chucks, boring heads,etc then there is plenty of reason for manufacturers to hope we will use that drawbar tooling in our new mills. Its really just the tang MT drill chucks that are used in the tailstock that won't be that useful.
We don't all have industrial machines many of us start with a lathe and do our milling with a vertical slide before being able to obtail a milling machine.
J |
Steve Withnell | 14/08/2011 19:35:54 |
![]() 858 forum posts 215 photos | If it's a Sieg X1 type then this is probably where I would start
Set of MT2 collets and a drawbar, job done.
Steve
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Bogstandard | 14/08/2011 19:46:55 |
263 forum posts | Forget the crap about having to go to R8 taper, I used morse taper tooling in my mill for many years before buying one with R8 fitting. R8 does have it's advantages, but when starting out, that is the least of your money spending worries. The only problem you have is at the moment you do not understand that to use any morse taper tooling in your mill, the morse taper has to have a threaded end so that you use a drawbar to hold the tooling in position. Morse taper tooling with a tang is really only designed only for use in either a drilling machine or in your lathe tailstock. There is also another catch as well, some MT tapers can have different threads (usually two different ones) in the end, so make sure you always buy tooling with the correct thread, or do as I did, have two drawbars so that I could fit either type. As suggested, a length of threaded rod on a smallish machine will be just fine for the second drawbar. Just on a safety note side. You should not use drill chucks for holding milling cutters except in very light loading processes, Drills actually have a soft shank and can be held with the hardened drill chuck jaws, but because you are trying to hold a very hard milling cutter shank with hardened drill chuck jaws, the cutter is liable to slip or become loose and so at the very least, ruin your job, but it could end up a lot worse. You really need to save your pennies up and buy say an ER collet chuck for holding cutters in your mill, or do as I do (costs about the same price) use dedicated spindle collet sets, they tend to give you a little more throat clearance, but are not quite as versatile as the ER series for holding different sizes.. I hope this explains it a little better. John |
Traction man | 15/08/2011 08:22:25 |
37 forum posts | I have a Chester Conquest mill which is MT3 which is the same as my lathe so I can use my boring head in both with a draw bar but most important you must not do the draw bar up to tight or you will not get the item out again easly. I had to take the spindle out of the mill after I used a spaner to tighten the draw bar. Now I make sure the taper is clean then firmly thrust it into the socket and then do the draw bar up finger tight, no more.you will find that it takes a good thump on the slakend draw bar to get the item out again. As mentioned above there are lots of diferent threds in use so I made up sets of draw bars for each of my items, one set for the lathe and one set for the mill. I agree with not needing to go to R8 one just needs to get used to the characteristics of what one is using. happy milling |
Stephen Rowley | 15/08/2011 10:40:46 |
57 forum posts 14 photos | Yes the mill is the Sieg X1 type and it is 6 years old. While I am at Bristol at the weekend I will see if I can collect some tapers with screw threads. I noticed when I was at the Chester's sell off week that their new mini mill is now called the Micro Mill and is smaller that the one I have. I also found that the Chester lathe I have has been renamed the 920. It is almost identical to the Conquest. Thinking of this I must start a new post to get hell with replacing the very thin drive bet on my lathe with one a bit more substantial. James |
Bogstandard | 15/08/2011 17:01:08 |
263 forum posts | BTW, Arc Euro have a great piece of kit for those that need the tang for auto eject on the tailstock or drilling machine, but also want to use them in machinery that has a drawbar. I have been using these for a couple of years now, and just having a few in stock can get you out of sticky situations. Half way down the page |
Traction man | 15/08/2011 19:24:17 |
37 forum posts | Hi James I agree it is confusing when they keep changing the names, when I got my Conquest Mill they also had a Conquest lathe very confusing. My mill is very like the Sieg super X2 to look at but unlike the Sieg the column can be angled like the Sieg X1 which sounds very usefull. But I found that it moved when taking a cut, so I have modified it with a removable locating pin to keep it vertical. I also found that when clamping the column up it moved out of vertical in the Y axis so I had to shim it. Apart from that its a great little machine that fits nicely on the end of my bench. David |
Stub Mandrel | 15/08/2011 21:29:51 |
![]() 4318 forum posts 291 photos 1 articles | I made a self-extracting drwabar for my X2 mill. Basically it has a 3/4" thick collar, you fit it so that the collar tightens against the end of the spindle. The top lock nut on the spindle is slightly thinned to allow a 'cup' shaped piece to screw onto the spindle thread, over the end of the drawbar (left hand thread, light hand tight fit only). the end of the drawbar has a square on it and pokes through a hole in the cup. To extract, put a spanner on the square and unscrew the drawbar - it pushes against the inside of the cup and 'plonk' the taper pops free. Sizes and tolerances must be determined by trial and error - make sure the drawbar is properly engaging with the taper, and have as small a gap between the collar and the cup as possible, so there is plenty of thread to take the strain of disengaging the taper. Neil |
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