Quick change tooling for the mill?

Anyone have any experience with R8 quick change tooling?
I have a Warco VMC and no standalone pillar drill. I do find it a pain forever changing from a milling to drill chuck. This happens mulltiple times during a typical workshop session.

The Cutwel EZchange system looks good on paper . It's not cheap though and I could easily invest in a pillar drill for about the same money.
However
1) I don't really have space in the workshop for a standalone drill press
2) I do like the mill DRO for spacing out holes for drilling.

Any feedback would be appreciated

Have a look at the Tormach TTS and it's clones on ebay etc. It uses a modified R8 collet that draws the tool holders up against the nose of the spindle so you can also put them back at exactly the same height

For drilling up to 1/4" dia. in my MT3 Warco, I use a small Jacobs chuck mounted on a 3/8" dia. parallel arbor. This fits into the collet chuck that is semi-permamently fitted to the mill. Much quicker than changing the whole thing and suffices for much of my drilling, but I do have a separate drilling machine.

Gloster Tooling also sell the Eazi-change system if you want to compare range and prices.

Consider investing in a drill chuck on a straight shank, the diameter to match your most-used milling collet. Hard work though if you do not have a power knee.

Until 2pm today, I had a Warco VMC mill. It was permanently fitted with an ER25 collet chuck which I used for milling cutters and drills, making use of the compressibility of the collets for odd size drills within the range of the individual collets. Purists will frown on that method but the I deliberately chose whole number sized fasteners in my designs, which helps. Tapping sizes are different, of course. I had a drill chuck on an R8 arbor, but rarely used it for the very reason stated by the OP.

John

I suppose it does depend to some extent what your method of holding milling cutters is.

Like John I use ER, 32 in my case most of the time and have a good range of stub drills in the common sizes including reaming and tapping sizes so use the ER for those most of the time only putting the drill chuck into the spindle for sizes that compress the collet a lot like a 4.2mm drill (M5 tapping size).

If you use an autolock type holder then it's either the complete change to drill chuck or have a small one on 1/2" or 12mm threaded shank

You can also make up some simple side lock type bushes for your commonly used drills and just put them into your milling tool holder,

Whatever you choose check that it does not eat into your Z height too much

I suppose it depends on what you're doing! I have an ER32 chuck, making drills no different from other milling tool-changes, mostly. Main exception is small drills, which are held in a small chuck plugged into a 3/8" collet, as described by Clive. Otherwise, the only time I switch from ER to a big Jacobs chuck is when I have to drill a large number of different sized holes in succession: that's rare in my workshop. Most of the time ER does everything - I can't remember the last time I fitted a big drill chuck to my mill.

Dave

My little CNC mill came with EZChange chucks - I think I have one BT30 holder and 2 or 3 ER16 collet chucks that fit it. Frankly it's a pain, quite hard to change from one chuck to the other in the holder without taking the latter out of the mill which defeats the object! Didn't someone describe a quick-change milling tool system that won the Stevenson Trophy a year or two back?

The holder system will add about 15μm of run out, on top of the 10μm that you'd expect from a "normal precision" ER Collet or endmill holder.

Cumulatively that 25μm (about 1 thou) will be enough to cause issues when running small endmills (below about 3mm carbide, 2mm has) and maybe cause vibration when power-feeding through a marginal cut which is towards the top end of the cutters capabilities.

Beyond that, they're very clear that it's limited to light milling cuts at moderate speeds, but don't define what those limits really are, so you probably need to feel that out over time to understand the limitations... You wouldn't for instance want to go straight in for a 5mm DOC, 50% stepover in tool steel with a carbide endmill, but that might be harder than you push your machine anyway.

.

If you're happy with those compromises and they don't negatively effect your work, it will most likely be fine.

.

Personally I struggle to see how it offers enough benefit over changing out tooling on a full shank to justify several hundred quid of outlay, as I only find it takes 15-20 seconds to swap a tool, but everyone's setup is different and you know what matters to you.

Thanks for all the feedback. I am using an "old school" Clarkson style milling chuck. I hadn't considered switching to ER collets. That looks to be the best way forward.

I would certainly lose the race in swapping my drill chuck for miling chuck. I certainly couldn't do it in 20-30 seconds!

People have suggested using a straight shank drill chuck but there is no reason that straight shank could not have a Clarkson thread on the end of it and centre in the end of it. Then changing to the drill chuck would be the same as swapping a cutter of the same diameter. It would lose a lot of head height.

You could also use the side lock bushes suggested above (or use loctite) to convert your most-used drill bits to Clarkson compatible.

Even if you later change to ER, these modifications will be compatible with the new purchase and will save time under both regimes.

I suspect it's individual to each machine and user, the ergonomics of reaching the drawbar and whether you have a spindle brake to work with will make a huge difference.

I'm used to machines having the drawbar nut exposed at the top/back of the spindle at all times with a long hex to ensure its accessible when the quill is down, a la Bridgeport.... But on a VMC it looks like it's buried inside the head and sinks with the quill, so I wouldn't manage to change holders as quick as that either with that arrangement.

Surprised no-one has developed a modification to the top cover to accommodate the same sort of drawbar as the Bridgeport for ease of use, given that the VMC seems to be a well liked and popular mill for its size.

Drilling a hole in the top cover, making two strategic cuts in the cover to separate a 90° segment at the front right corner, then attaching that corner permanently with two screws, would allow a long, always accessible drawbar to poke through the cover, without interfering with the guarding of the belts.

Not nearly as neat as the quick change spindle nose though!

Edited By Jelly on 14/06/2023 20:03:48

I considered the EZchange system many years ago for my Bridgeport, but was advised that the mill would exceed the capabilities of the holders. I now use the TTS system on the Bridgeport, largely because I also have a Tormach mill.

On the Bridgeport the drill chucks, 10mm and 6mm endmill holders and the Haimer edge finder and Centro are on the TTS system, along with some ER20 collets holders. I rarely use the ER collets, most milling is done with 10mm and 6mm cutters. I have to remove the TTS collet when using MT drills, the Clarkson clone holder, large endmill side holders and boring and facing heads. But they don't get used that often.

Andrew

DC31k, like this? Tapped and plugged the end with a suitable bolt then cut off the excess, faced and drilled the centre before adding the thread.

Martin C

For my cnc router that has an ER20 spindle taper, I got tired of the tool length changes etc. So I made a series of solid holders that were ER20 and then either a standard tool size like 8mm 6.35 for 1/4 inch, 6mm and 4mm. These were bored at the time the holders were made from the bar.

I also made a series of ER20 solid holders that have an ER11 taper and thread on them. The ER11 holders, have a thread in the back for length stop adjustment, so that the cutters etc can be the same length.

So the tools can be changed and not have to scan and reset every time. They are very handy to have on the mill when wanting to change out a cutter to another size. The collet nut, does not need to be any where near as tight compared to holing the cutter in the collet. But not as quick as changing in 10 seconds though. But is quicker than changing with a loose cutter and a collet.

There are companies like Big in Japan that make nose fitting tooling for high precision milling.

I am sure that there will be a way of making something up to get repeatable tooling lengths, but the Cutwell System is very slick , and the 3k rpm limit is ample for manual machines. I am sure that you could play with the installation to get the best possible run out with your machine.

I would want to get quite a few of the different holders for sure, and like you mentioned, that becomes real money very quickly when the main adapter, and then the various holders. I am sure that you could make your own holders, but won't do it for the price they are selling them for.

Removing the tooling from the spindle every now and then is a good thing, as you don't want frozen or jammed tooling in the spindle.

I use the Easychange system (from Coventry Engineering - but it looks identical to the Cutwel version) on my Myford VMF mill, specifically because I converted it to cnc and wanted the ability to change tools easily without having to reset the lengths every time. I have 3 or 4 of both ER16 and ER32 holders.

It works very well, except maybe for bigger cutters such as 16mm long series endmills, and is certainly convenient.

As you say, it is expensive, but only you can decide whether that matters!

Dave

I have a VMC with R8 taper and share your frustration. Havent got around to it yet, but I wonder about adding a collar to the drawbar between the top of the R8 collet and the inside of the spindle so that unscrewing the drawbar self ejects the collet. Then making a hole in the belt cover to allow the drawbar to be screwed and unscrewed using a cordless drill with a socket.

In the meantime, I've removed the R8 alignment pin from the spindle, which at least saves a few seconds each time I change the tooling.