Easy add quick connect collets or changers to an existing CNC

Hi all,

I've had my CNC (Avid 4848Pro) for a bit over a year now I think and overall I'm really happy with the machine, but I've already gotten sick of changing bits. I know an ATC would be the ultimate solution, but looking at the options out there (https://www.cncdepot.net/product-pag...d-cnc-machines), I'm not ready to drop another ~$5,500 bucks just to make my life a tiny bit easier (I'm a hobbyist, so there's no ROI to be had here). I have the 3kW spindle package from Avid with a bunch of collets. Is there anyway for me to add some sort of quick changer to this spindle so I can keep a few of my most used bits preloaded for faster changing?

Funny you should ask about this...there was a post on Camheads about something that might be able to help you...

https://www.usroutertools.com/muscle...et-p/mc-14.htm

You can get ER20 and ER25 collets that are solid and you heat shrink the tool into them. Becomes kind of a quasi-quick change set up, they can tend to be a pit pricey, $100 or so per holder, but if you only need two or three, it might be worth it. Made by Iscar, by the way. Let's see if I can add a picture:
https://www.paragon-supply.com/image...44_Enlarge.jpg

I was trying to think of something along the lines of what Brian posted, but maybe a side clamp or something. Don't think I've ever seen any with another collet on them. Still requires getting in there with a couple wrenches.

Cheapest solution is the tool length touch pad. Swap them out by eyeball, touch them off, and go.

Next up is a quick change spindle but do the tool changes manually. But that saves what, a rack and some software?

Dumb(er) solution, a collet and nut for each tool, 'lightly' Loctite the cutter in the collet. Poor mans heat shrink holder, with far less overhang.

Those heat shrink holders are available in different lengths, think the picture is of a long one. I purchased a bunch of extra nuts and collets so I have my common tools already with the collet snapped into the nut and the tool inserted, so it's just unscrew, install and tighten and then use the length setter and push cycle start. I write my programs to bring the machine to tool change position and put an M00 to stop the program.

As a side note... I was planning on a CNCDepot spindle at some point and lately I have heard nothing but bad news about them, locked up spindles, not ejecting tools, shot bearings... so I would have to do a lot of research before I use one of theirs.

I was thinking they probably don't make heat shrink at standard collet length. I was wrong. And all the way to a 1/2" shank.

https://www.haimer-usa.com/products/...lets-er20.html

I added an ATC spindle to one of my Avid tables several years ago. It uses tool holders that drop out with the push of a button. Cost was around $2000 on Ebay.
David

Attachment 477955Attachment 477956

Hi David,

Any idea what they unit weighs? My Stepcraft is somewhat limited on how much weight I'm going to be able to put on there without upgrading the motors or devising a counterbalance system.

Thanks!

Hi Brian,
I would say at least 25 to 30 lbs. It is much heavier than the 3 HP air cooled spindle I have on my first CNC Router Parts (Avid) router table. It is ATC water cooled about 4 hp.
Uses NBT-ER25 tool holders with ER25 collets. I just weighed one of the tool holders with collet and it is 1.5 lbs. Physical size of the spindle is 4" OD x 15" long. I have this ATC spindle mounted to an Avid Pro4824 table. Stepper motors are NEMA 34 960 oz-in.

David

Well, the CNC Depot spindles are 23.5lbs according to their website and that is what is used on the Stepcraft Q series machines like mine. I talked to them (Stepcraft) and they said probably 35 lbs without doing anything to counter the weight of the spindle. A couple of small air cylinders on either side with a regulated air supply would be an easy way to counter balance the spindle, but I was trying to keep things simple.

Do you have a link to the eBay seller for yours, I quickly looked on eBay and didn't come across anything.

One other little annoying detail about shrink fit. The cutter has to be solid carbide for the expansion differential to work. And the tolerances of diameter are tiny. The smaller the shank, the smaller the tolerance. Little chance a steel shank brazed carbide 'router bit' will go in and be held properly. And if it does, you probably won't ever get it out without boring the remnants to foil and peeling it out with a scribe.

Air cylinders? What's wrong with a chunk of cast iron suspended by chain and sprockets like my Fadal? ;-)

Quote:

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Originally Posted by Brian Lamb

Well, the CNC Depot spindles are 23.5lbs according to their website and that is what is used on the Stepcraft Q series machines like mine. I talked to them (Stepcraft) and they said probably 35 lbs without doing anything to counter the weight of the spindle. A couple of small air cylinders on either side with a regulated air supply would be an easy way to counter balance the spindle, but I was trying to keep things simple.

Do you have a link to the eBay seller for yours, I quickly looked on eBay and didn't come across anything.

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Hi Brian,
I ordered from the same Ebay seller as Bobby Milam did around 3 years ago. Here is the thread where I had asked Bobby for detail on his ATC spindle.

https://sawmillcreek.org/showthread....nts&highlight=

I checked my Ebay purchase history and it only goes back 2 years, so I really don't know who the seller is by name or item number. The seller does have some videos on Youtube here:

https://www.youtube.com/user/tivoi/videos

At the time of my purchase, the cost was around $1800 plus shipping. The seller is located in Viet Nam, but I expect the actual spindle is Chinese.

Here is a video of Bobby Milams spindle/atc setup.

https://www.youtube.com/watch?v=R0c5StkFUWc&t=84s

Brian - I found a copy of the Ebay listing for the ATC I purchased. Bobby Milam bought his from the same seller. I don't know if this seller is still active on Ebay and I couldn't find him using an Ebay search by member. But there must be similar spindles out there. This Ebay seller was really great, because he would test each spindle before shipping and provide a Youtube video showing the exact spindle I was to receive. It still had my name marked on it just as shown in his video.

By the way, I converted this Avid Pro4824 table to use the Centroid Acorn contoller and am still in the process of completing my actual ATC. I have it all built and working, but just need to program the macro using the xyz coordinates of each of my atc rack tool holder positions. Bobby had already done the same thing (except for the sliding tool holder rack) and he talked about it in some of his posts.

Here is the search for his posts to make it easier to find these threads.

https://sawmillcreek.org/search.php?...d=17719030&pp=

Let me know if you decide to go the ATC route with Centroid Acorn and perhaps you will motivate me to finish up mine.

David


Attachment 477974

The nice thing about this one is that the seller included the spindle, vfd (pre-programmed), tool holders/collets, tool forks, spindle mount, air regulator, solenoid valve, wiring, etc. Pretty much everything needed. I ended up ordering more tool holders and collets from the same seller. These are very high quality and I was quite impressed that the tool holders were only $20 each and collets $4 each. Nice stuff!
David

Quote:

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Originally Posted by David Buchhauser

Let me know if you decide to go the ATC route with Centroid Acorn and perhaps you will motivate me to finish up mine.

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David, etal.....
In the next couple months I will be working with the Centroid software development team to build/improve the Router ATC program. Actually it doesnt really need improvement in function, just form. We will be bringing the ATC function variables and settings, along with the required macros into the Wizard to make it much easier for the DIY crowd, like yourself to build a working ATC systems on routers be as elegant and full featured as the Mill and lathe versions.

Also, and in the same timespan, CNCDepot should be releasing an Acorn based ATC controller for Teknic ClearPath servos that we have co-developed. This will be an all in one control with the VFD, all pneumatics on board, and a custom screen with all ATC functions on screen buttons.

If you hang on (or procrastinate) a bit, your ATC setup may become much easier.