collet concentricity

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MedWoodWorx

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i hope this is the right place to start this thread.
I am stocking up all the tools needed to start making kitless pens. Since my collet chuck is ER25 i had a really hard time finding big collets i.e. sized 18 & 20mm. The thing is that the guy at the shop that is selling them mentioned that these collets are not meant for highly accurate jobs. The concentricity according to the website is 0.02mm. Is that ok for penturning? i suppose that my woodlathe is not the most concentric tool in the world either..what are you guys thinking? maybe more machinist oriented folks among us know more about this? @rherrell ?
cheers, Mike
 
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0.02mm is 0.00078 inches or... less than 1 thousandth of an inch. That is very good for a wood lathe.

My collets are all ER32 and I check them for runout with a mandrel in the collet so that I am checking for runout at the end of the piece I am working on.

Now, this is just my opinion, but for me, that is accurate enough for what I am doing. After all, we are not threading bolts for the SpaceX Starship or a Ferrari F1 Car.
 
The eshop selling them is german specialising in machining not penturning; i suppose they are serious about their stuff..
 
i hope this is the right place to start this thread.
I am stocking up all the tools needed to start making kitless pens. Since my collet chuck is ER25 i had a really hard time finding big collets i.e. sized 18 & 20mm. The thing is that the guy at the shop that is selling them mentioned that these collets are not meant for highly accurate jobs. The concentricity according to the website is 0.02mm. Is that ok for penturning? i suppose that my woodlathe is not the most concentric tool in the world either..what are you guys thinking? maybe more machinist oriented folks among us know more about this? @rherrell ?
cheers, Mike
We use ER32 as well, we did find the Beall collet chuck set to hold collets much better than our previous collet chuck, so it seems a good chuck can make a significant difference. I realize you probably can't get ahold of Beall, but what I'm saying is a good quality chuck.
 
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ER collets were designed to hold tools not work. Good quality ER collets are typically under .0004" TIR. Very good quality are under .0002". The quality of the chuck and how concentric it is on the lathe probably makes more difference in most folks' case.

There are plenty of ER collets for sale that are garbage, though.
 
ER collets were designed to hold tools not work. Good quality ER collets are typically under .0004" TIR. Very good quality are under .0002". The quality of the chuck and how concentric it is on the lathe probably makes more difference in most folks' case.

There are plenty of ER collets for sale that are garbage, though.
True
 
Rick Herrell posted to a similar thread here a couple of years ago. His post includes a video on how to tweak the runout on a pin chuck held in a collet. I think the same could be applied to a blank/rod or other item that is held in a collet. If nothing else the procedure would give you an indication of the amount of runout. - Dave
Yea i ve seen it and actually tried it. To my dissapointment my chuck is not concentric as it should be. However i ve used it to hold mandrels and have made many pens since with no (noticeable) problems. It seems that i have to work with what i have all the good stuff are in usa and it costs a small fortune to buy them from american suppliers.
 
This is the brand of collet that I own and recommend, very good quality without breaking the bank...


I use collets primarily for holding the work, not the tool, I have endmill holders for that.

.02mm is plenty good enough for a wood lathe, IMO.
 
We use ER32 as well, we did find the Beall collet chuck set to hold collets much better than our previous collet chuck, so it seems a good chuck can make a significant difference. I realize you probably can't get ahold of Beall, but what I'm saying is a good quality chuck.
Beall Tool closed its doors/was bought out. Their ER32 collet chucks are very accurate in my experience...much better than a commonly available alternate chuck and collet set. Sometimes, the chuck and collet sets can be found on line from other vendors.
 
.02mm is more than accurate enough for what we do.
However, collet chucks are, normally, only designed to go up to a certain dimension. For example, the ER32 collets I use normally only go up to 20mm. But I have been able to purchase collets put to 25mm off of Aliexpress. They work, but the material in the collet is getting very thin and I'm not sure I trust their repeatability. You will likely run into the same problem if you find the bigger diameter er25's, as they are only intended to go to 16mm.
While it is an expense, I would invest in an ER32 set. While the Beal ones mentioned above, were bought out and now sold by Lee Valley, I have a PSI set and have had no issues using it on my wood lathe for marking kitless pens. It is considerable less money. Then you can purchase a complete set of 3-20mm chucks on Amazon for as low as $70. I paid $140cad for mine. The metric set is better, as there are no gaps in the sizing, which does occur in the imperial set.
 
Beall Tool closed its doors/was bought out. Their ER32 collet chucks are very accurate in my experience...much better than a commonly available alternate chuck and collet set. Sometimes, the chuck and collet sets can be found on line from other vendors.
You can still get Beall through Lee Valley.
 
The metric set is better, as there are no gaps in the sizing, which does occur in the imperial set.

Granted metric would be better for me & easier to use but...

My imperial set is in 32nds through 25/32" and don't understand the gap in sizing. Old-fartitis on my part?

FWIW, at one time I saw the Beall runout spec to be up to 0.005" but never saw that on mine.
 
We use ER32 as well, we did find the Beall collet chuck set to hold collets much better than our previous collet chuck, so it seems a good chuck can make a significant difference. I realize you probably can't get ahold of Beall, but what I'm saying is a good quality chuck.
Lee Valley purchased some of the rights to Beall tools when they closed their doors. Looks like they still have the collet chuck:


Is this the one you were referring to? I have a collet chuck myself, but it was just one that I found at Woodcraft (probably Wood River brand) and I don't know that its great quality. At some point here I'll be getting into kitless myself, and I've wondered if my chuck would suffice, or if a better one would be needed. I generally like Beall's tools...if this is the same quality chuck you have, I might pick one up.
 
My imperial set is in 32nds through 25/32" and don't understand the gap in sizing. Old-fartitis on my part?
I took this chart from the thread below and use as a reference. This shows the differences between imperial and metric collet sets. It shows the imperial collets needed to get the full range. Some imperial sets are smaller (18 piece) and do not contain all of these collets. I believe that is where the gaps are.


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I took this chart from the thread below and use as a reference. This shows the differences between imperial and metric collet sets

The only non-overlap that I see is 0.002" at the 13/16"
If I'm not mistaken, I also have a 1/16" collet.

I still wish that I had a metric set.
 
Lee Valley purchased some of the rights to Beall tools when they closed their doors. Looks like they still have the collet chuck:


Is this the one you were referring to? I have a collet chuck myself, but it was just one that I found at Woodcraft (probably Wood River brand) and I don't know that its great quality. At some point here I'll be getting into kitless myself, and I've wondered if my chuck would suffice, or if a better one would be needed. I generally like Beall's tools...if this is the same quality chuck you have, I might pick one up.

FYI...I wanted the Beall collet chuck without the collets because I already had the collets I want/need. I called Lee Valley and they were able to sell me just the ER32 collet chuck and wrenches. The price was very reasonable.
 
Lee Valley purchased some of the rights to Beall tools when they closed their doors. Looks like they still have the collet chuck:


Is this the one you were referring to? I have a collet chuck myself, but it was just one that I found at Woodcraft (probably Wood River brand) and I don't know that it's great quality. At some point here I'll be getting into kitless myself, and I've wondered if my chuck would suffice, or if a better one would be needed. I generally like Beall's tools...if this is the same quality chuck you have, I might pick one up.
Yes, we just very recently purchased this set and find it works much better for us after struggling with a lot of wobble with our previous entry level collet set.
 
Yes, we just very recently purchased this set and find it works much better for us after struggling with a lot of wobble with our previous entry level collet set.
Am I correct in that these appear to have threads, and screw onto the lathe spindle? The collet chuck I have now is actually MT2 and just fits inside the spindle. It has actually never fit entirely snug, even when I really try and WRENCH it in there, which is a bit problematic. For the stuff I mostly use it for, its been fine, but, I doubt it would work well for kitless pen crafting.
 
Am I correct in that these appear to have threads, and screw onto the lathe spindle? The collet chuck I have now is actually MT2 and just fits inside the spindle. It has actually never fit entirely snug, even when I really try and WRENCH it in there, which is a bit problematic. For the stuff I mostly use it for, its been fine, but, I doubt it would work well for kitless pen crafting.

Yes, you choose the spindle thread you need. I purchased the chuck (w/ wrenches) only in a 1" - 8 TPI for my Jet 1221VS Midi Lathe and love it.
 
Am I correct in that these appear to have threads, and screw onto the lathe spindle? The collet chuck I have now is actually MT2 and just fits inside the spindle. It has actually never fit entirely snug, even when I really try and WRENCH it in there, which is a bit problematic. For the stuff I mostly use it for, it's been fine, but, I doubt it would work well for kitless pen crafting.
Yes, what @d_bondi said, it's just such a nice set, I don't think you'll have regrets. My only regret is that we didn't get one sooner. I've noticed when I turn nib holders, I get far less chatter and the wobble is gone when working on the tail. We're very happy with it.
 
Am I correct in that these appear to have threads, and screw onto the lathe spindle? The collet chuck I have now is actually MT2 and just fits inside the spindle. It has actually never fit entirely snug, even when I really try and WRENCH it in there, which is a bit problematic. For the stuff I mostly use it for, its been fine, but, I doubt it would work well for kitless pen crafting.
The chuck you have is usually locked into place using a draw bar.
Here is a link to an article on Beauforts web site.


You could make one yourself.
 
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