Hey all!
New to the forum I’ve been using my MR1 for a couple months now. I just bought a Tschorn 3d Tester with the 1/2" Shank. I put it in the machine last night and checked the run out and it was way out. I pulled the nut and the collet and blew everything out real good made sure nothing could be offsetting the collet.
I put a 1/2" endmill in to check its run out and it was very little. When I put the tester in there I can see it with my eye when i turned it that the probe is moving around in a circle vs the spindles axis. These have set screws to set the runout but this is outside what they can adjust. Does anybody have any other suggestions of what else I can adjust on? I’m just trying to get it close so I can use the set screws to finish it off the rest of the way.
Right now the highest point of the runout is a full spin of the needle on my indicator.
If you dont have enough setscrew movement, it sounds like something may be bent? All the Tschorn units Ive seen are long, which one do you have?
Model 001V2DB05I. I ordered a new 1/2 collet cause I wondered if that would be a possibility as well. I actually Chucked the Tschorn in my drill and just turned real slow to see if I could see that much movement in the probe on there and it wasn’t doing the same. The only part I could imagine might be bent is that collet. I’m not sure where else I could look. I just replaced the spindle block last week so I know that is all brand new.
When you say you replaced the spindle block, what are you refering to? The entire bottom of the Z axis assembly?
It almost sounds like your collet isnt properly seated in the collet nut.
So I had a bearing issue and had to swap out that whole lower piece of the z axis that holds the spindle. It’s all trammed back in and everything. I found some metal around the inside of the collet nut and blew it all out and it’s still out a ways. I’m going to keep digging. New collet should be here tomorrow if I maybe managed to bend something there somehow.
Are you using the Langmuir spindle? If you are not using the collet that came with it that may be your problem? Aftermarket collets won’t work. The Langmuir spindle is 24 mm x1.5. Standard ER20 collets are 25mm x1.5.
Yes, they screw on but are too loose.
If you have changed your spindle, disregard this rant.
Langmuir had made 100 of spindles with the wrong threads. They have the correct collet nuts for sale if you are so inclined.
Nope I’m using Langmuir spindle. I am using the 1/2" collet that came with the kit. I didn’t realize aftermarkets won’t work. That’s good to know.
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Try the OEM collet nut and let us know how it works. You should email Langmuir and get yourself several. They are not expensive.
To clarify, the collets are interchangeable but the nut is specific because of the special thread. I haven’t grabbed spare nuts yet, but I keep meaning to order them.
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Sorry I forgot to answer that earlier. I am using the OEM collet nut. I have a spare from the spindle change out. Maybe I’ll try the spare OEM nut and see if it changes anything.
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It will. That 25 mm nut goes on and tightens. But it is not clamping correctly.
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For anyone that needs one, here is the link to it in the online store.
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Ok I think I’ve narrowed it down to the Tschorn tester itself being the problem.
Changed the collet changes the OEM nut. Got the same run out. I finally pulled everything off the spindle ran my indicator on the spindle it’s dead on. Put the nut on ran it on the but again maybe a couple thou needle barely moved. Put the Tschorn tester in and locked it in. Ran the indicator on the top shaft of the tool again just a couple thou each way. Tested the probe again and it’s a full turn of the needle out. I appreciate you guys helping me. Glad to see it’s definitely not the machine. I’m going to go through the gauge and see what I can find.
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I’m up and running!
Doesn’t have anything to do with the machine but you guys have helped us much you deserve the final findings
Started pulling the Tschorn apart and looking then finally I noticed the top collar that has the set screws was not on center. Was trying to find how to move it cause whatever is holding it is also not allowing the set screws to move it. Finally found a metric Allen head going through the center of the top. Loosened it half a turn and the color was free. Snugged it up a bit so the set screws could do their thing and put it back in the machine and put the indicator on. Now I’m within a few thou of the axis and things look good.
Thank you guys again for all your help.
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