Collets for Mill/Drill

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Hope you Grizzly folks don't mind my posting here, since there is lots more traffic.......I have one of the RF30 clones (I think Enco) very similar to the Grizzly G3358, or the G1006.

My question is about what tool holding to use. The Mill/Drill has an R8 spindle. I know I can use R8 collets for holding both end mills and drills, but that the shanks have to be the exact size of the collet. Taking into consideration the tram issues if the head is raised or lowered, as well as the tool shank sizing on the R8 collets, I am wondering about getting an R8/ER32 collet adapter to use. My thought is that using the ER32 collets gives me a bit more of a range of shank sizes to use if I needed to get an odd drill here or there. The ER32 collets and adapter would also offer a similar protrusion from the spindle if I needed to change to a drill chuck or an endmill holder. My thinking is that this would help remove the need to raise the head of the mill while working on a part, and avoid the re-tramming issues with round column mills.

Am I close to being correct? What thoughts or suggestions are there on this? What other considerations and options have I overlooked?
 
I have an RF-31 so I'll give this a shot.

Yes, an ER-32 chuck is a good option vs R8 collets, for the reasons you mentioned. One system you might look at is the Tormach TTS system. Their system uses a 3/4" R8 collet with a flat ground nose to hold their tools but many tools will fit into it. Their ER-32 chuck is under $40.00 and is totally adequate. The good thing about the TTS system is that you only need to loosen the drawbar and exchange tools instead of exchanging R8 collets - very fast to use.

An ER-32 system will hold anything from 1/16" OD up to 3/4", is very accurate with good collets and a good nut, and takes up about the same head space as a drill chuck. You would need a large collection of R8 collets to accommodate all the tool sizes an ER set will accommodate. Like all systems, cheap collets are not worth their cost so if you go with an ER chuck, buy decent collets. Techiks, Crawford, ETM, Rego-Fix and Lyndex are some good ones. I would avoid Chinese collets unless you are strapped for cash; runout can be an issue with these. Buy a good nut - I like ETM and Rego-Fix nuts.
 
I've had endmills slip in collets so I use endmill holders now. For drill bits I would go with an R8/J3 arbor for this Accupro drill chuck, which I now have and love.
 
I use an Albrecht keyless chuck on an R8 spindle when I need to use a drill that I don't have a collet for.

Everybody talks about the hassle of a round column mill, but if you raise or lower the head all you have to do is throw in an edge finder and reset the x, the y won't change if the head's reasonably in the same place.
 
I'm probably missing something, but I dont see the advantage of the TTS system. It looks to me like its an ER collet holder with a shaft being held in an R8 collet, instead of an ER collet holder with an integral R8 shank. What have I missed?
 
Nothing you missed. It is much faster to loosen the drawbar, remove the chuck and replace it with another tool. With an integral R8 holder, you have to loosen the drawbar, knock the R8 arbor loose, then totally unscrew the drawbar and then screw the drawbar in to tighten the next tool. The TTS system takes seconds to swap tools and they are held securely and with precision. You can certainly live without the TTS system; I just prefer it.
 
To add to what Mike said about the TTS system, the shank on them is much shorter than an R8. So chances are there may be many more times where you can make a tool change without havingto move your table to the side or lower your knee or raise the head to get the tool out.

This happens to me a lot. I just live with it & luckily I have a DRO which makes it quicker but everytime it happens to me I think about the TTS. Just not having to fully unscrew the drawbar to change a tool alone is worth it IMO.

Unfortunately it will be too costly for me to swap over to the TTS system, well more than I want to spend but who knows, I still might make the change one day.
 
I use endmill holders for the same reasons posted above, collets can slip with heavy cuts. For drill bits I just use a drill chuck on an R8 == Jack
 
I never liked end mill holders, I use a lot of carbide end mills and the vast majority of the HSS end mill, do not have the Weldon pocket. I'm not about to start grinding a flat in a new end mill. With R8 collets, Din 6388 collets and ER32/40 collets, I've never had an end mill move. Maybe I'm lucky or the fact I make sure the collet and the endmills are clean and dry, before use.

What work for one, may or may not work for others.
 
Nothing you missed. It is much faster to loosen the drawbar, remove the chuck and replace it with another tool. With an integral R8 holder, you have to loosen the drawbar, knock the R8 arbor loose, then totally unscrew the drawbar and then screw the drawbar in to tighten the next tool. The TTS system takes seconds to swap tools and they are held securely and with precision. You can certainly live without the TTS system; I just prefer it.

Got it, I understand the possible advantage now, thanks for the explanation.
 
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