# ER collet torque



## Aukai (Feb 27, 2020)

Does anyone actually torque their collets?


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## middle.road (Feb 27, 2020)

Does 'gut' feeling count?


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## Aukai (Feb 27, 2020)

Calibrated elbows?


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## DavidR8 (Feb 27, 2020)

Aukai said:


> Calibrated elbows?



Stephan Gotteswinter has a calibrated arm 


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## pstemari (Feb 27, 2020)

If you look up the torque specs, you'll probably find that you'll need longer wrenches to get enough torque to meet spec. I upgraded from the stamped Taig handles to a pair of 1" Martin service wrenches, with about 6" handles, but I'd still need about 80lb force on the handles to get the recommended 42 ft-lb of force.

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## darkzero (Feb 27, 2020)

I torque mine. I use .75 GG on my ER-16 slim nut & 1.8 GGs on my ER-40s.


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## mikey (Feb 27, 2020)

Will, what is a GG?


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## middle.road (Feb 27, 2020)

mikey said:


> Will, what is a GG?


I'm wagering 'Gorilla Grip'


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## darkzero (Feb 27, 2020)

Gorilla Grunts.  

I never knew about them until I started getting older. 

ER-40 nut torque is somethig like 125 ft/lbs. No way that's gonna happen in my shop. I haven't had anything slip in any of ER chucks in my little mill, not yet anyway.


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## mikey (Feb 27, 2020)

Ah soooo ... 

Aukai, to use a torque wrench, you need a fixture to hold the chuck so you can apply the proper amount of torque. Most ER chucks have at least two or more opposing flats on the chuck body that makes fabricating one a simple deal. The problem with applying torque is that most adapters are made to fit an exchangeable head type torque wrench. These are common in Europe but not common here so they are expensive to purchase. You can use a standard square head torque wrench with a crow's foot if you can find one in the right size for hex-shaped collet nuts. If you have the nuts with the slots in them then you have to buy that expensive type of wrench. Quite frankly, most hobby guys just use the "GG" approach and have no issues with hobby-class depths of cut.


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## darkzero (Feb 27, 2020)

Just looked it up. 130 ft/lbs for ER-40. Mari Tool says 15% less for bearing nuts. That's still 110 ft/lbs. I doubt I'm getting even close to that using 2 wrenches with no chuck holding fixture.






						MariTool
					






					www.maritool.com
				






> The following torque ratings are for solid ER style collets nuts. Bearings collets nuts are not as strong so reduce these values 15%
> 
> When clamping on shanks 30% smaller than collets maximum capacity, reduce torque value 40%.


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## darkzero (Feb 27, 2020)

mikey said:


> The problem with applying torque is that most adapters are made to fit an exchangeable head type torque wrench. These are common in Europe but not common here so they are expensive to purchase. You can use a standard square head torque wrench with a crow's foot if you can find one in the right size for hex-shaped collet nuts



I suppose the reason why they don't commonly sell adapters to be used with a common square drive torque wrench is the accuracy. When you add an accessory like a crow's foot the crow's foot should be oriented 90° from the handle so it doesn't alter the length much at the point of rotation to get an accurate reading.

So if you were to just use the adapter pointing forward or any angle other than 90° the torque value will not be accurate. I wonder how much the torque value will vary & if it is even that much of a difference. I remember learning about torque wrenches & crow's feet in auto shop courses at an adult center but that's about it. And that was like over 20 yrs ago.

I'm sure there is a formula for calculating the variance. This is dejavu & I feel like we have talked about this here before. I even remember searching for those square drive adapters & only found them in the UK or Germany. A diagram similar to this is also familar.


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## mikey (Feb 27, 2020)

Yup, you can use a crow's foot at 90 degrees and it will be accurate. Problem is finding one that fits your ER nut and also fits a square drive torque wrench.


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## Aukai (Feb 27, 2020)

I learned something, and have a plan, thank you....
Necessity is the motherhood of butchery....


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## higgite (Feb 27, 2020)

Of course I torque them. Who doesn't? I just don't know how much. Probably, one GG on the Darkzero Scale. Of course, that's one old GG. You might even call it one GGG (Geezer Gorilla Grunt). We geezers have to be careful how hard we grunt, if you get my drift.

Tom


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## Cadillac (Feb 27, 2020)

German spec is good-n-tight.


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## Firstgear (Feb 27, 2020)

You guys make me laugh!  Thank you!


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## Norseman C.B. (Feb 27, 2020)

I use one URRF or two depending on the situation ...........


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## pstemari (Feb 27, 2020)

darkzero said:


> I suppose the reason why they don't commonly sell adapters to be used with a common square drive torque wrench is the accuracy. ...
> 
> So if you were to just use the adapter pointing forward or any angle other than 90° the torque value will not be accurate.



The adapters typically won't fit on a square drive torque wrench. They are straight, but the ones I've seen have a special tang that goes directly into the torque wrench.

One could always measure the length of the handle, and then come up with a weight to hang from it to get the appropriate torque .

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## darkzero (Feb 27, 2020)

pstemari said:


> The adapters typically won't fit on a square drive torque wrench. They are straight, but the ones I've seen have a special tang that goes directly into the torque wrench.



Yep. These are the ones I was referring to in that post that aren't commonly found.


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## middle.road (Feb 27, 2020)

Taking this slightly off-subject but not too much.
In another post (which off course I can't seem to locate...) someone mentioned having extra nuts for their ER32 collet chuck.
_Is the nut a known standard_?
I have two imports, one with a R8 that I use in the BP and another with an MT3 shank that I use on both lathes.
I've been chewing on this for the 'wish-list' thinking that it would be nice to have the collets already setup in the nut to save time.


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## Aukai (Feb 27, 2020)

I was going to sacrifice my collet wrench from the ETM set that has that head on it, and set it up for my torque wrench. I'll see if I can find that one.


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## Aukai (Feb 27, 2020)

But not for $111.00.....


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## darkzero (Feb 27, 2020)

middle.road said:


> Taking this slightly off-subject but not too much.
> In another post (which off course I can't seem to locate...) someone mentioned having extra nuts for their ER32 collet chuck.
> _Is the nut a known standard_?
> I have two imports, one with a R8 that I use in the BP and another with an MT3 shank that I use on both lathes.
> I've been chewing on this for the 'wish-list' thinking that it would be nice to have the collets already setup in the nut to save time.



I saw that one too. That was a first for me, I had never heard of anyone having spare nuts & collets to save time on changes. I usually see people having entire spare chucks already setup. I have a second ER-40 chuck for this reason & cause I got a good deal on it from a member that used to be local to me.

But as far as I know the threads should be a standard but not necessarily the outer dimensions of the nut. I have used various brands of nuts on all of my ER chucks which are also various different brands, they all fit & worked.


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## Seedtick (Feb 27, 2020)

Norseman C.B. said:


> I use one URRF or two depending on the situation ...........


OK, and what, pray tell, is a URRF and what is the determining factor that justifies the use of a second one? Hmnn?


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## higgite (Feb 28, 2020)

middle.road said:


> Taking this slightly off-subject but not too much.
> In another post (which off course I can't seem to locate...) someone mentioned having extra nuts for their ER32 collet chuck.











						[Newbie] - MT3 vs R8
					

I'll take my MT3 mounted drill chuck with me tomorrow and see if it fits. I do know what Tormach makes an MT3 adapter to their tooling system and MT3 ER-n collet chucks are easy to find.




					www.hobby-machinist.com
				



I might could see that in a production environment where time is money, but not for me personally as a hobbyist. To each his own, but I'd rather spend that money on something else that I don't need but can't live without.  


middle.road said:


> _Is the nut a known standard_?
> I have two imports, one with a R8 that I use in the BP and another with an MT3 shank that I use on both lathes.
> I've been chewing on this for the 'wish-list' thinking that it would be nice to have the collets already setup in the nut to save time.


The nuts have standard threads for each ER size. There are different style nuts, though. For instance, I have 2 styles of ER32 nuts, the "plain" one that came with the chuck and I also bought a bearing nut that makes torquing it down easier and more consistent. Some nuts also have different grooves around the periphery for wrenches.


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## NortonDommi (Feb 28, 2020)

My ER32's are supposed to be done up to 100 lb/ft as I change cutters on the mill I did some measurements a couple of years ago and the best I can get is around 80 lb/ft.  Never had anything come loose or slip so I guess FT is good enough for manual use.


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## NortonDommi (Feb 28, 2020)

Seedtick said:


> OK, and what, pray tell, is a URRF and what is the determining factor that justifies the use of a second one? Hmnn?


I believe that one URRF is a clench and a two URRF is a very tight clench anymore and pants go to the washing machine.
  I'm not sure but an URRF may be the Metrickery of a GG.


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## darkzero (Feb 28, 2020)

NortonDommi said:


> I'm not sure but an URRF may be the Metrickery of a GG.



Haha! I'm gonna have to add that to the list!

Imperial Guys: Dead Nuts, Ugga Duggas, Gorilla Grunts
Metric Guys: Spot On, Ratta Tats, URRFs


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## royesses (Feb 28, 2020)

Make your own er collet adapter post #137:








						What have you done in your shop lately?
					

I recently learned the fascinating info about files, here is the link for newbies like me:  Nicholson file guide   Yeah the File Filosophy book is great :)  I've found I enjoy file work. Keep buying more files and taking on more manual projects. It all kinda started when I was deburring some...




					www.hobby-machinist.com
				




Roy


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## finsruskw (Feb 28, 2020)

Cadillac said:


> German spec is good-n-tight.


You spelled it wrong...
It's Goot-n-tight


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## Cadillac STS (Feb 28, 2020)

I made this handle extension and always feel the collet it tight. Never had a slipped end mill


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## Cadillac STS (Feb 28, 2020)

darkzero said:


> Yep. These are the ones I was referring to in that post that aren't commonly found.
> 
> View attachment 314928


Easily make one of those by cutting off a wrench and milling a square in it.


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## Jester966 (Feb 28, 2020)

I bought one of these for at work:








						Techniks CNC Machine Tooling | Adjustable Torque Wrenches
					

PART NO. TORQUE RANGE  LENGTH  WEIGHT  SPIGOT   60 TH 5-45 ft/lbs  11.5"  1.2 lbs.  16mm round   200 TH 30-150 ft/lbs  16.5"  1.75 lbs.  16mm round   300 TH 45-228 ft/lbs  21.5"  2.5 lbs.  16mm round




					www.techniksusa.com
				



It is about 18" long.

I torque ER32's to 100ft/lbs.

The standard ER32 wrench is only 10" long.  Out of curiosity, I have used the torque wrench with my hand placed in the same position as it would be on the standard wrench, and it is _very_ difficult to torque to 100ft/lbs with only 8-10" of leverage.

At home I only have a standard 10" ER32 wrench, and based on this experiment, I basically have to tighten _as much as I possibly can_ to get the same amount of torque.


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## higgite (Feb 28, 2020)

darkzero said:


> Imperial Guys: Dead Nuts, Ugga Duggas, Gorilla Grunts
> Metric Guys: Spot On, Ratta Tats, URRFs


So, a URRF is a metric GG. Got it! Now THAT makes sense!

Tom


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## higgite (Feb 28, 2020)

darkzero said:


> Just looked it up. 130 ft/lbs for ER-40. Mari Tool says 15% less for bearing nuts. That's still 110 ft/lbs. I doubt I'm getting even close to that using 2 wrenches with no chuck holding fixture.
> 
> 
> 
> ...


I just got around to looking at that Maritool torque table that Will posted. I had never seen the tidbit about reducing torque by 40% on shanks smaller than 30% of collets maximum capacity. What that tells me is for my ER-32 lathe chuck with 3/4” capacity, when I’m turning a piece of round stock that is less than .525” OD, the torque required is ~100 ft-lbs - 40% = ~60 ft-lbs. That may help explain why I’ve never had slippage in a collet, although I’m sure I’ve not been always tightening the collet nut to 100 ft-lbs, if ever. Also, what is finally sinking into this petrified brain of mine is that the proper amount of torque is not only about eliminating slippage, but can also reduce runout. Just when I thought I knew it all, I found that I didn’t… again. But, with this new info, now I’m sure I do.   

Tom


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## darkzero (Feb 28, 2020)

Cadillac STS said:


> I made this handle extension and always feel the collet it tight. Never had a slipped end mill
> 
> View attachment 315000



Nice TP! I haven't seen one in a long time. I used to have a TP65A. I really wanted a TP75A for my current lathe but couldn't find one.


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## Norseman C.B. (Feb 28, 2020)

NortonDommi said:


> I believe that one URRF is a clench and a two URRF is a very tight clench anymore and pants go to the washing machine.
> I'm not sure but an URRF may be the Metrickery of a GG.



Well Norton ya pretty much nailed it on the first description  .....................


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## Cadillac STS (Feb 28, 2020)

darkzero said:


> Nice TP! I haven't seen one in a long time. I used to have a TP65A. I really wanted a TP75A for my current lathe but couldn't find one.



I got that DTM tool post as new old stock a few years back. Works very well.


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## darkzero (Feb 28, 2020)

Cadillac STS said:


> I got that DTM tool post as new old stock a few years back. Works very well.



Agreed, it is a very nice TP. Apparently one or some employees who left Aloris created Dovetail Tool Manufacturing. They were said to have improved on Aloris' design (I noticed guides for the wedges). I also purchased mine new from a guy who purchased the remaining stock from DTM when they closed their doors. Was told the owner retired or something like that. 

Then I got a new lathe & wanted the next size up. Contacted that guy but he did not have any, just parts. I still have an original DTM brochure that he gave me. I still search ebay for a TP75A (BXA size) every now & then even though I don't really need one. I just really liked that DTM for some reason.


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## NortonDommi (Feb 29, 2020)

Cadillac STS said:


> I got that DTM tool post as new old stock a few years back. Works very well.


Cheers


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## NortonDommi (Feb 29, 2020)

Norseman C.B. said:


> Well Norton ya pretty much nailed it on the first description  .....................


Cheers.


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## Cadillac STS (Feb 29, 2020)

Here is a nice little mill project for torquing your collets. It is one of the first things I made years ago. You may have one, just sharing the idea.

There are bench top mounted jigs for this purpose for other collets but I’ve never seen one for the ER type collets. And everyone has a vise.

This little jig gives you something to torque against and not torque on your machinery or hold with another wrench.

Mill it to match the collet body with a loose slip in fit. And with a lip on it to be able to just drop it in the jaws and not have to take any time to align it and squeeze it in the jaws

The vise is only there to slightly snug in the jig and not to clamp the collet body in it. No need to have the collet body tight you are just going to tighten the nut.

Keep it handy with your collet set, drop it in the vise and torque it down


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## Cadillac STS (Mar 1, 2020)

To check the actual torque you need a torque wrench. I was in Harbor Freight yesterday and saw this digital torque adapter for the wrenches you already own.  It also comes in 3/8.




Then with the collet wrench you already own put a 3/8 or 1/2 inch square near the top leaving enough room to put on the wrench.

Can cut the square hole with or without a mill. Draw the square then drill a hole in the middle and square it out with a file. ****NEW TOOL OPPORTUNITY ALERT***  If you don't already have a small triangle file that would fit in this hole can order one of those to square out the hole then have it for your tool collection.*  Could cut off the handle of the collet wrench short or just leave the handle on to use it without the torque wrench.

For about $30 you can know the torque. Probably less searching Amazon for a torque adapter.


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## mikey (Mar 1, 2020)

Just a FYI. The torque adapters for ER chucks sold by Techniks and others is made to fit a 16mm spigot torque wrench. The one Techniks sells is made by Norbar. These wrenches have a round tip with a spring-loaded ball on one side that fits into a hole on the torque adapter. There are torque adapters to fit almost any ER chuck nut out there but you have to have the torque wrench to use them ... irritating.


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## kd4gij (Mar 1, 2020)

I use the old school method, As tight as you can get it and one turn tighter


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