Do the int 30 qc 30 and iso30 all use the same locknut
I know they all have the same taper but the flanges differ but doesn't the locknut just drive the tool up into the taper.
The reason I ask is because I have a Bridgeport textron series II interact with a heidenhain. I have been using qc 30 tooling but I'm thinking that the tool is not being seated in the taper properly because I'm having weird runout readings I put a dowel in a collett holder will maybe have a .005 runout take the tool out back in then will maybe have a .002 runout then repeat the process and maybe get a.001 runout then back to .005 etc.. I'm just wondering if I used a int 30 tool with a thinner flange it would get up in the taper better.

There are a bunch of different collets that are used in that size. The ER and accuraflex are similar sizes but incompatible.

maybe I was misleading on my problem Gus it is the actual tool holder flange I'm having issues with not the collets I don't know if qc30 by kennametal is the correct flange for the quick change lock nut

can you actually move the tool holder around in the taper(i dont mean really obvious looseness,if the taper is only just seating sometimes you can twist the tool slightly between the driving dogs) when the locknut is done up?,,,,and out of interest how many button head screws are around the locknut?

There is 3 button head screws around the locknut. I've concluded that it must be the qc30 flange because the locking nut only has a 47 mm hole in it so it wouldn't even take the 50 mm flange that a int30 has. but i did some test with some high spot bluing and found that I have no contact on the big diameter portion of the taper so I definately have some wear causing bell mouthing on the machine taper I'm having a spindle grinder come take a look

Mmmmmm it'll be interesting to see if thats the problem .I recently bought a br2j machine that when I first saw it had an r8 spindle wich was nice because i have been collecting r8 tooling,when i went back to the machine sales to hear it running they said that when they started it with the r8 head it was making a horrid noise so they had fitted a complete head with a qc30 spindle from a later machine!!!!! so the big search for qc 30 tooling started!!! its been a nightmare but i have learned a lot ;o) yesterday i machined a non qc int 30 holder to fit the qc locknut and it has worked nicely so at least now I know I can make slightly cheaper tool purchases work for me. Qc 30 tools in the uk seem to be hard to find second hand and are bloody expensive new .I have a spare qc lockring wich has got 6 screws around it,the one on the machine has 3 like yours ,I have had them both to pieces they are identical and both have qc written on them,one is made by bristol erickson and the other (the one with 3 bolts) is made by kennametal,I have also been able to adjust the lockring too so that i can use a tool that i machined the flange slightly too thin on, anyway I'll watch for your test results,Jay

Your dead right in beleiving its the spindel taper in the quill,I have a interact with the same taper and it does exactly the same thing.I have found that over the years in hast tools get installed without being cleaned properly and it burrs up the taper inside.I found by removing the locking nut and blueing the taper i could turn the machine on at a low speed and polish the high spots of, and got resonably good results.Just be carefull only to use one finger with the emery paper ,and dont go to fast or press to hard,Good luck regards greg.

Greg
I think I've done those tactics to much unfortunately they did work though for the time being but I have quite a bit of no contact area you can actually see the bluing make a wave type of design between the contact and no contact areas about .200 from the large diameter of the taper

If you remove the qc 30 lockring you can take the driving dogs off the bottom of the spindle(each dog is retained by one bolt),you could then use an old int30 tool holder and some cutting paste ,maybe valve grinding paste to lap the taper back.....you would obviously want to put the paste on the high spot areas first to bring the non contact areas back into line....i used this idea on a gear shaping machine with good results....its gonna need a good clean out after though!

The lock nut eventually wears and the tool can loosen up, especially under load. Thus it must be adjusted periodically. The worst case I saw of this was at a steel mill lab (Tuscaloosa Steel making dog bones for destructive testing). They had tape wrapped around the tool holder to take up the clearance. At that point a new spindle and lock nut were ordered.

George

Yeah they sure can loosen up I had it spit a couple of holders out under load I adjusted it a little have not had any problems with that again but still a little reluctant to put that one tool holder in I'm taking the spindle out to have Precision spindle in Ferndale Michigan take a look at it does anyone know if there is some archive threads on removing the quill and spindle out of a bridgeport series II interact?