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View Full Version : quick change opinions



deth502
05-23-2008, 09:17 PM
never thought i needed tehm before, but i just got a grizzly g0602 lather and i think the supplied turret is horible.

first, it looks liek id be looking for a 100 series, yes?? are the sizes pretty much std?? (any 100 series holders from any manuf will fit/ be the same size??)

second, piston vs wedge. pros and cons for each??

ERBenoit
05-23-2008, 10:39 PM
Search the archives. This dead horse (topic) is forever being beaten here.

Chipslinger
05-24-2008, 08:36 AM
And......Lather?
Is that what they call it at Grizzly or in Pa.? :)

deth502
05-24-2008, 08:59 PM
spell check is not my friend :(

:)

did a search first and didnt come up with anything here.

got it now though, good thread on them over on practical machinist forum.

JRouche
05-24-2008, 10:34 PM
First off, I dont care about yer writing skills or spell check, yer ok by me.

Second, I am thinking its a ten inch swing?? I looked it up. I have two ten inch lathes and I use the 200 series holders. Its pushing the limit but just happened to be the size I went with. As for piston or wedge. I like the wedge, not really knowing if one is better than the other, just appeared to me the wedge type would be more consistent along the whole clamping range..

And thirdly, sure, this topic has been brought up many times. Not a problem, keep bringing the old, or for you, the new topics up. This is a home shop environment and so a repeat of older topics is OK.. Always.. Really, its way on topic for the group and dont any of you hesitate to re-hash some on going issues. Anyone have a problem with helpin out ANYONE here, no matter how many times the issue has been talked about should think about moving on to another more "current" group. Hmmm, PM site is open for new talk.... And Im not bashin PM cause I love that group also....

I do suggest using the search function though. So many great topics from the past.. JR

deth502
05-24-2008, 11:19 PM
like i said, i tried the search and came up empty. a few threads came up, but not for the specific question i was looking for. perhaps i just didnt happen to use the appropriate search words.

from what i found, the 200 series seem to be for lathes with toolpost heights that would put mine right at the minimum height, so im assuming that woul;d mean the bottom of the holder would be touching the cross slide, im thinking if i get a stray chip when im trying to change tools, that could be a problem.

from what it looked like, either would work though, but for the reason stated, i chose the 100 series. i wasnt happy with the 3/8" tool limit, but i figure i can get a holder and mill it out for 1/2".

also, it seemed no one had anything good to say about the piston types, other than they were a few $$$ cheaper.

this afternoon, i "biy'ed" one on ebay, $140 total w/ shipping for a 100 series wedge type.

so i dont have tht much in it should i not lik it, or it fail.

ther were alot of people asking if anyone had tried the cheap ebay ones, but no responces. i know im always scheptical of deals that seem to good myself, but i figure if there are some minor shortcomings on it, id be able to fix them.

so i guess ill be the guilea pig on the cheap ebay qctp's :)

ill post some first impressions when it comes in, and we'll see how it works.

MickeyD
05-25-2008, 12:45 AM
Break down and get a BXA (size 200) Aloris or Dorian set. You will probably get a bigger lathe one day and can use them on it, plus BXA is a lot more rigid than the smaller ones. Aloris or Dorian posts are a joy to use and the tool holders are common and using the cheap chinese holders from CDCO and ebay is not a sin. The little bit of pain that you will feel when you buy a good tool post will fade a lot faster than the daily pain that you will endure using a cheap POS wedge post. Been there, done that, and gave it away to a broke friend who was trying to tool up an inherited lathe.

JRouche
05-25-2008, 03:05 AM
l

from what i found, the 200 series seem to be for lathes with toolpost heights that would put mine right at the minimum height, so im assuming that woul;d mean the bottom of the holder would be touching the cross slide,

Eactly!! Mine sits right on the cross slide, this is on the SB 10L, The 10ee is right there too. I have about a sixteenth of an inch really to bring the tool holder up to center. Just barely made it. But it works, and I can put a 5/8" holder in there.. I think the 100 series woulda been a lil small for the 10ee but yer 10" lathe might be just right for the 100 series.... All good... JR

toastydeath
05-25-2008, 03:22 AM
Anyone in the HSM community ever look into VDI-style quick change holders? They're used on some CNC turning centers, they're the precursor to Capto quick change holders. Repeatability and rigidity is apparently excellent.

They seem like a fairly easy thing to make if you have the tooling to make it.

Some pictures:
http://www.marathon-excel.com/vdi.htm

A tangental piston mates a grooved slug to the grooves on the toolholder, pushing it down and backwards to lock it in.

Sandvik seems to have a whole line of interchanging, interlocking tool holding options for the lathe that do not seem all that difficult to make. They're just grooved plates you bolt similarly grooved cutting tool holders to. So one could make up a bunch of VDI holders, or even a bunch of standard quick change holders with the Sandvik-style grooves on it and be able to assemble whatever kind of tool you need rather than having dedicated quick change holders for boring bars, turning tools, drills, etc. Seems like it would cut down on the inventory of toolholders and whatnot.

deth502
05-29-2008, 10:54 PM
so, i got my cheapo qctp from ebay in the mail today.

first impressions, looks to be of high quality, nice fit and finish on it.

looks to be appropriatley sized to fit the lathe.

machined the t-nut to fit, and i put it on the lathe. didnt get a chance to turn anything with it yet.

this may be known to all here, but i was expecting the wedges to be forced out to hold the toolholders. how it works is the wedges are tapered, and the center has a large acme thread that forces the wedges down, and therefore out, to hold the holder.

the only shortcoming i can see is that there is a bit of play in the slide of the wedges. as in they can "rattle around" in the slot, if you can understand what im getting at, so that when yo release a tool, the friction holds the wedge against the tool, so you have to turn it out far, then turn back in a little to take out the slack so the holder can be released.

all in all, compared to the prices ive seen them going for, im happy with it.

ill check back in if i come across any probs once i start using it, but i dont forsee any.