R8 Collet Set What Should I Buy????

In comparing R8 to ER32 which is easier to use?
I have read conflicting info on the force necessary to tighten ER chucks with some saying that it takes over 100 ft lbs of torque to tighten and others saying they just need to be tightened with the standard spanner wrench. Looking at the size of a standard spanner wrench no way you would be able to apply anywhere close to 100 ft lbs of torque. So what does it take to tighten ER chucks?
It seems to me that ER chucks and collets would be easier to use. Once you tighten the ER chuck in the quill you are done messing with the draw bar. All of the collet changes happen at the chuck. On the other hand with R8 collets you have to loosen the draw bar and break the collet loose (might have wrong terminology) every time you need to change the tool in the collet or change to a different size collet. What are your experiences with changing ER and R8 collets?
If I go with ER collets I am thinking about buying them from CTC Tools. Anybody have any experience with CTC Tools. I'll get R8 collets off Ebay if I go that route. Cost seems to be about the same.
Thanks for all your suggestions.
Chuck
 
[QUOTE=". Any reason that you guys can think of why I shouldn't buy a metric set instead of an inch set? Chuck[/QUOTE] Yes I Can !!!!!!! it was AMERICAN TOOLS that built the Saturn V Rocket that put Neil Armstrong on the moon not this metric nonsense !!! If AMERICAN TOOLS are good enough for NASA they are good enough for me !!!!!!!!!!! ok ok mild rant over, seriously dont buy cheap tools regardless, a broken drill or end mill in a part is not worth the time ,cost or frustration.. buy quality first,, FYI everyone, Taiwan is an ally of the USA, they buy millions of USA military hardware,in the top 10 of cnc manufactures world wide,so if you HAVE to buy asian, Taiwan first..
 
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Chuck, neither seems difficult to me but I'm sure others have a preference. It isn't a big deal to tighten or loosen an R8 collet and tap it loose when removing a tool. Its actually faster to do this with an R8 collet vs an ER collet. When tightening a tool in an R8, you only need about 30 lb/ft of torque for most work (according to Tormach).

An ER chuck is supposed to be tightened in a fixture, not in the spindle. Different chuck sizes require different torque values to properly tighten the nut. For example, an ER-25 only needs 25 lb/ft of torque, while an ER-32 needs 100 lb/ft and an ER-40 needs 130 lb/ft of torque. So, if you do this correctly and need to change tools you need to remove the ER chuck from the spindle, put it in the fixture, loosen the nut, change the tool and torque it to specs, then put the chuck back in the spindle and torque the chuck to 30 lb/ft and you're set. This is what you're supposed to do.

I'm going to guess that most hobby guys don't own an ER chuck fixture and just change tools with the chuck installed in the spindle. To change tools this way, you need two wrenches; one to hold the chuck body and another to loosen and tighten the nut. Of course, you cannot expect the best performance from your tools if you don't torque the nut properly so you have to decide how you want to deal with this.

Personally, I use the Tormach TTS system and use their fixture to tighten the nut on my ER-32 chuck BUT I admit that I don't use a torque wrench, mostly because I don't have an adapter for my torque wrench to fit the nut. I can get pretty good torque with the spanner and I know what 100# of torque feels like so I fool myself that I'm pretty close.

So, ease of use? R8 is easier to me. Less torque required? R8 wins again unless you go with the ER25 system that requires only 25 lb/ft of torque and will hold most commonly used smaller end mills. Cost? Hmmm, for just tool holding on the mill, I think R8 wins because you only really need the common sizes. Loss of head room in Z? R8 wins by being more compact. Accuracy? I think the ER system is more accurate if used properly, which is why its sort of an industry standard vs the R8 system, but in a hobby shop I wonder if you would be able to tell. Which one to choose? Your call. I have both and use both. I like the ER system because the same collets work on both the mill and lathe.

As for collets from CTC tools, don't know anything about them but I'm sure someone here does. If they are Chinese, then all I can say is that there are better collets out there and it pays to buy good collets.
 
Contrarian opinions follow:
I use a chuck for drilling, not a collet in my mill. Often i'm center drilling, drilling and tapping each hole. (center drill, move to next hole ditto, etc.) Were I to use collets I'd have to change collets for each hole, 4 holes, 12 changes. Since I only have 1 3/4" travel on my PM25, I'd have to raise and lower the head to change R8 collets. No way. I use a drill chuck for each op. Since I work primarily in aluminum, I can start a tap with a chuck, back it out (with the chuck) and finish it by hand out of the mill.
My R8 collets are 1/8 graduation, no end mills I have are other sizes. I do NOT use end mills in the drill chuck, it wasn't made for them.
 
I decided to go with ER32 collets because I can use them on my mill/drill and my lathe. From the pictures of the collet chucks I have purchased on Ebay but not yet received the chuck bodies appear to have flats on them so you can hold the body of the chuck to tighten the nut.
My mill/drill has 4 1/2" of travel on the quill and the maximum distance from the quill to the table is 16 1/2." Not a lot of room to work with by the time you get everything set up.
If I am only doing drilling and tapping I will probably use the drill chucks that came with my lathe. Both chucks have MT2 shanks and I have bought an R8 to MT2 adapter for the mill. I have bought an R8 to ER32 chuck for the mill and a MT2 to ER32 chuck for the lathe. I bought a 19 piece ER32 collet set that covers from 2mm to 20mm. Still waiting from most of this stuff to arrive.
 
I'm sure it will all work out, Chuck. The ER system is a versatile system. The only issues you may have is on the lathe. The beauty of the ER system on the lathe is that it allows stock to pass through the chuck and out the spindle; can't do that with an MT2-ER chuck. Eventually, you may want to sort out a better solution.

All ER chucks should have some way to put a wrench on the chuck. You may even want to build a fixture that will allow you to loosen and torque the chuck by indexing on those flats. The torque applied to an ER nut is not just to secure the tool, but to also assure concentricity of the tool. When torqued properly, the end mill or whatever will run more accurately. Since you've chosen to go with metric collets you'll need to torque down to an imperial sized shank so this torque thing may be more important than you think.
 
Mike,
I do plan to make or buy an ER32 chuck for the spindle so that I can pass work through the spindle of my lathe. My lathe is a craftsman 12x36 with I believe a 25/32 bore so 3/4 stock will fit through the bore. It is just one more thing on the list.
Chuck
 
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