Inexpensive TTS ER20 Collet Chucks Still Available?

[extdrive]

I bought a batch of TTS style ER20 tool holders from YSTOOL on ebay. I did some testing on them today after I was getting unexplained chatter. I was measuring .005-007" of run-out on the worst couple in the batch. I'll test the rest in the next couple days. Maybe I got a bad batch. Very disappointed in them. I've emailed the seller to see if he is willing to refund/exchange them. For reference my genuine Tormach TTS holders all measure less than 0.0005" of run-out.

I misspoke regarding the run-out I was seeing on those tool holders. It was late when I was running the test and I guess I was tired because I forgot I was using the 0.0005 indicator and not the 0.001 indicator. So the run-out was really only half as bad as I thought it was. Still unacceptable though. For anyone keeping track here are my results from testing all 10 of them again today.
1. 0.003" (.062mm)
2. 0.004" (.1016mm)
3. 0.002" (.0508mm)
4. 0.0025" (.0635mm)
5. 0.0015" (.0381mm)
6. 0.0005" (.0127mm)
7. 0.0035" (.0889mm)
8. 0.004" (.1016mm)
9. 0.004"(.1016mm)
10. 0.003" (.062mm)
I posted a quick video of the test on youtube to send to the eBay seller. He replied to my first email and I'm hopeful he is willing to make things right.

[extdrive]

Thanks for posting that. The test you are using does not test the holders concentricity in isolation, however is probably fairly representative.

Please see my report attached. Cheers Keen

I agree, your setup is better. I didn't have a v-block and maybe the patience to be as thorough as you were. I think given a sample set of 10 though its probably statistically representative of the run-out. I ought to have included video of the runout of my spindle and R8 collet as well, both well under 0.0005.

[extdrive]

Quick update: I got a package from ebay seller YSTOOL today. Came all the way from China. Not sure how he got it here this quick. We agreed just 2 days ago that he would send replacement ER20 tool holders. The package included 10 tool holders. 5 of the style I originally purchased and 5 that appear to be ATC compatible. So maybe he is going to start selling ATC compatible holders on ebay. I didn't have much time at lunch so I only tested one holder for runout. It had less than 0.0005" YAY!!! I'll test the others when I get a chance and report back if they are not of equal accuracy.

[extdrive]

Tested the rest of the holders. One didn't test real well. The others were acceptable.
Video here
youtu.be/Ly8o0cID6UE

[cs13368]

I think that MillFast Products still has a few on their web site. They say used but the one I saw looked new.

[extdrive]

So the ebay seller never asked for these tool holder with excessive runout to be returned. Would anyone have a use for them? I can't think that I will need them. They don't have the nuts because I had to steal them for the new tool holders I was sent. But if anyone wants them and is willing to pay shipping they are yours.

I misspoke regarding the run-out I was seeing on those tool holders. It was late when I was running the test and I guess I was tired because I forgot I was using the 0.0005 indicator and not the 0.001 indicator. So the run-out was really only half as bad as I thought it was. Still unacceptable though. For anyone keeping track here are my results from testing all 10 of them again today.
1. 0.003" (.062mm)
2. 0.004" (.1016mm)
3. 0.002" (.0508mm)
4. 0.0025" (.0635mm)
5. 0.0015" (.0381mm)
6. 0.0005" (.0127mm)
7. 0.0035" (.0889mm)
8. 0.004" (.1016mm)
9. 0.004"(.1016mm)
10. 0.003" (.062mm)
I posted a quick video of the test on youtube to send to the eBay seller. He replied to my first email and I'm hopeful he is willing to make things right.

[jdclark]

Do these holders pull up against the spindle or the collet- I got some and on my machine the collet protrudes past the spindle nose, so the holder was just indexing against the tapered end of the collet. I turned the end of the collet flat, and they were fine.

[extdrive]

Ya that's a good thought. I had wondered that myself. But I checked the stickout of my R8 collet and it was less than the recess in the tool holder.

Do these holders pull up against the spindle or the collet- I got some and on my machine the collet protrudes past the spindle nose, so the holder was just indexing against the tapered end of the collet. I turned the end of the collet flat, and they were fine.

[extdrive]

They've been claimed

[philbur]

Also for accurate measurement with a dti the stylus must be parallel to the surface being measured otherwise you get a cosine error.

Page 23 here explains:

https://www.mitutoyo.co.jp/eng/produ...Indicators.pdf

Phil

[extdrive]

That's not quite accurate. You want the stylus perpendicular to the direction of the movement you wish to measure. So in this case I would want my stylus parallel to the axis of the spindle, not the taper of the tool holder. You are correct though my angle was still not parallel to the axis of the spindle. I'm probably within 25 degrees and my resulting error would be no greater than 10%. Good enough I believe for this application.

Your point is well taken though. It was bad form on my part to make a video with dti stylus at a bad angle.

Also for accurate measurement with a dti the stylus must be parallel to the surface being measured otherwise you get a cosine error.

Page 23 here explains:

https://www.mitutoyo.co.jp/eng/produ...Indicators.pdf

Phil

[brian257]

Wondering if anyone has found a low cost set screw TTS type holder? Ystool is still selling the ER TTS clone chucks on Ebay, but no set screw holders.

[SCzEngrgGroup]

Novakon (www.novakon.net) sells set-screw holders and ER chucks, and their "Gold Series" have guaranteed maximum runout - 100% factory tested.

Regards,
Ray L.

[GLCarlson]

Novakon is 16 bucks for set screw holders, 5 cheaper than Tormach and about what Yusing ER20 costs. They appear to be on clearance. 6mm are 10 bucks (and a quarter inch reamer would probably fix the diameter if you need quarter inch). No runout spec I can find, though.

Looks as if set screw holders are on clearance, lots of "no stock" flags.

[brian257]

Thanks Ray, I didn't know that Novakon sold those. Not sure what the deal with the no stock is.

Good idea on the reamer GL. Could also bore some out bigger. I did order ten of the ER20s from Ebay today.

[SCzEngrgGroup]

Not closeout, just not always in stock. There's not huge demand, and the make them in batches, so are sometimes out of stock on some items. Not sure they have "Gold" setscrew holders, but if you e-mail them, you can get the "straight poop".

Regards,
Ray L.

[brian257]

OK, thanks. Not really sure that I would need super accurate set screw holders. I use them for larger size end mills and will use my most accurate ER collet holders for the really small end mills. I did order several of the set screw holders that they had in stock and I will compare the accuracy to my Tormach TTS holders

[GLCarlson]

Thanks Ray, I didn't know that Novakon sold those. Not sure what the deal with the no stock is.

Good idea on the reamer GL. Could also bore some out bigger. I did order ten of the ER20s from Ebay today.

So I grabbed a couple, and set up in the lathe. Reamed 0.2500. No trouble reaming with HSS chucking reamers. Quarter-inch carbide mills go "pop" after reaming, and the TTS side is 0.7495 according to my mic. Didn't check hardness of the shank. They fit my 1100 just fine. Setscrew is metric, but 3/8 16 size, flat. Runout on the reamed units was <0.0003 with a carbide test bar, in my mill.

Short summary- these seem to be decent, and are around $11.50 apiece with shipping. If you've got drills and reamers, they're about half the price of the Tormach setscrew holders for 5 minutes of work. No cone on the TTS end, no groove for ATC, and probably not enough depth in the 1 3/8 ring to make them ATC compatible (don't know, don't have an ATC). They're identical to the original, non-ATC TTS holders Tormach sold, at least visually.

For comparison, 1 3/8" 4140 HT TGP is 20 bucks a foot, plus shipping - call it 8+ bucks for a piece long enough to make one setscrew holder, plus machining time.

Incidentally- John Saunders did some accuracy checks on setscrew holders. He believes they are both better overall for holding tooling vs ER20, even without a Weldon flat, and runout was negligible. He's published a video on his channel.

[brian257]

No cone on the TTS end, no groove for ATC, and probably not enough depth in the 1 3/8 ring to make them ATC compatible (don't know, don't have an ATC). They're identical to the original, non-ATC TTS holders Tormach sold, at least visually.

.

I just got the ones I ordered a few days ago. Some of them have the cone on the end and the groove for ATC and some don't. The low cost ER collet holders from Ebay I recently got don't have the cone either. I will probably grind cones on them all on my surface grinder at some point.

[SCzEngrgGroup]

You can easily cut the cones and ATC grooves on a lathe using a carbide insert parting tool. It's actually kinda fun - the chips come streaming off glowing bright orange! You should ask if they have them with the cones and grooves already in them. They do for the ER chucks, and probably would be willing to do so for the set-screw holders if there's enough interest to justify making them.

Regards,
Ray L.