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  #1  
Old Sun 28 October 2007, 19:12
WTI
Just call me: James
 
Detroit (Michigan)
United States of America
Auto Tool Changer

This thing runs under Mach3, and looks to be the cheapest ATC I've seen.

Do you think we could adopt it to our devices, or better yet, make our own version?

I would think that maybe 5 tools would be all we would ever need around here, and even that would be a lot.

Here is the changer:

http://www.littlemachineshop.com/pro...ProductID=3065

Here is a video of it in operation:

http://www.littlemachineshop.com/vid...ChangeDemo.mpg
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  #2  
Old Sun 28 October 2007, 20:27
driller
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There are better designs and easier ones to use.

I fear the cost will still be 4 figures when all is said and done.

http://www.youtube.com/watch?v=UJRVX6HyNTU
uses a zeroing switch.

There are quite a few auto tool changers for routers like this.

Dave
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  #3  
Old Sun 28 October 2007, 20:52
driller
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Here is another router option.

this has all the parts needed in a high speed router.

Dave

http://www.talkshopbot.com/forum/mes...tml?1186162715
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  #4  
Old Sun 28 October 2007, 22:57
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
These toolchangers all need a hole down the center of the armature/rotor shaft, from the top of the router all the way through to the collet. Then a "drawbar" is inserted down/through the hole and this pulls the cutter into the collet. It has to pull quite hard, and a pneumatic cylinder is used to do the pulling. Imagine the thrust loads and the bearing forces . . . . .
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  #5  
Old Mon 29 October 2007, 06:23
driller
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Quote:
Originally Posted by Gerald D View Post
These toolchangers all need a hole down the center of the armature/rotor shaft, from the top of the router all the way through to the collet. Then a "drawbar" is inserted down/through the hole and this pulls the cutter into the collet. It has to pull quite hard, and a pneumatic cylinder is used to do the pulling. Imagine the thrust loads and the bearing forces . . . . .
The units typically have either thrust bearings or springs directly on the shaft. In either case, there is no pressure on the motor bearings while the unit is running, except for a little added weight. But, all milling machine centers have auto tool changers.

By far the easiest to use is the Tormach system, if they ever perfect it.
all you need is a tool holder on the end of your table. the Z presses down to release the tool, then slides away to seperate.

then presses down on the next tool.

no pressure on the motor beyond that of a small cutter, and no additional electrical or pneumatic systems. I blow-off would be neat, and easy to add without much extra work.

Dave
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  #6  
Old Mon 29 October 2007, 14:14
Belli
Just call me: Greg
 
Johannesburg
South Africa
Hi All,

The draw bar has fingers that draw the pull stud up into the taper, holding the tool in place. The draw bar is usually pulled up with some bellville washers, the pneumatic cylinder doesn't touch the draw bar at all while the spindle is turning but when it is stopped it extends against the drawbar, compressing the bellville washers which allow the fingers to release the tool. It is usually a single acting, spring return cylinder.

Hope this seems clear as mud??

Greg
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  #7  
Old Tue 30 October 2007, 07:49
GregW
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How about something simple and something the MechMate could build for you?

http://www.hightechsystemsllc.com/

It's advertised to only run to 10,000 RPM but since that speed was placed on the web site the building has upgraded the springs to a much stronger make. I have one of these systems, just haven't had anything to mount it to. One of these days in the near future a MechMate will have one installed. You may need to build one of the axis ("X") about 3" longer for the tool holder to rest outside the work area.

I was impressed by the simplicity and rugged build of the tool holder. Just my 2 cents.
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  #8  
Old Tue 30 October 2007, 08:13
driller
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Quote:
Originally Posted by GregW View Post
How about something simple and something the MechMate could build for you?

http://www.hightechsystemsllc.com/

It's advertised to only run to 10,000 RPM but since that speed was placed on the web site the building has upgraded the springs to a much stronger make. I have one of these systems, just haven't had anything to mount it to. One of these days in the near future a MechMate will have one installed. You may need to build one of the axis ("X") about 3" longer for the tool holder to rest outside the work area.

I was impressed by the simplicity and rugged build of the tool holder. Just my 2 cents.


yup, this system works with any rouiter that can hold a 1/2" bit and the change type is a Z motion down to release or a Z-motion up to engage.

Low cost overall and it is used on the mini-mill to metal cutting. That means it can stand up to the work load of a wodd router.

He is out of stock currently. I have the origional version, not a good design as the holders would spin in the housing. The new version uses the balls to lock in recesses. AFAIK, it is much better.

I was looking at putting in a keyway like the big machines. I'll probably make a new holder as the one I have is trashed after the bits spun up and ruined the surface.

I am not happy about the origional design, but the new design should work much better.

Dave
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  #9  
Old Tue 30 October 2007, 08:54
GregW
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Dave,

I've got the new design just haven't been able to install it in anything yet. It does lock in tight. I meant to add this little video of it in action but ComCast wouldn't let me so I put in on my other web site.

http://www.styrolines.com/Tool_Change.wmv

I talked to Derek and he said he's not going to make any more unless there are some orders coming in. Too bad too, as this is a good little addition to any CNC machine.
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  #10  
Old Tue 30 October 2007, 10:50
driller
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Quote:
Originally Posted by GregW View Post
Dave,

I've got the new design just haven't been able to install it in anything yet. It does lock in tight. I meant to add this little video of it in action but ComCast wouldn't let me so I put in on my other web site.

http://www.styrolines.com/Tool_Change.wmv

I talked to Derek and he said he's not going to make any more unless there are some orders coming in. Too bad too, as this is a good little addition to any CNC machine.

I almost canot believe he is not making any. It says patent pending, and I know that costs a bundle !

I think he over-priced his stuff when he went to the ER collet as the only holder.

The old holders were 1/4 of the price, I have 8. that means for the same price, I would only aford two of the new holders. Kinda hard to get excited about two holders changing tools.


Dave
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  #11  
Old Tue 30 October 2007, 22:38
GregW
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Quote:
Originally Posted by driller View Post
I almost canot believe he is not making any. It says patent pending, and I know that costs a bundle !

I think he over-priced his stuff when he went to the ER collet as the only holder.

The old holders were 1/4 of the price, I have 8. that means for the same price, I would only aford two of the new holders. Kinda hard to get excited about two holders changing tools.


Dave
Over priced? Find me a cheaper tool changer and I'll buy it. The collets??? Check MSC for the price of a collet. As someone already stated the old version wold spin in the holder. These don't.
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  #12  
Old Wed 31 October 2007, 07:16
driller
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The origional holders were like $25 each, the new ER ones are about $90 each, plus the collets.

It is a low cost solution, but the home hobbiests that make up the market find it pricey.

You can make your own holder for #30 holders, and they cost about $30 each on e-bay.

I did not say they are over priced for the use, just that the market (home hobbiests) that I have spoken to think they are.

As you can tell, he is not getting orders. Other than cost, and the origional ones slipping, I have not heard bad things about his units.

The new design fixed the slipping problem.

That only leaves one thing.

I like the idea
I like the design
I would like to have the units.

I would like the option to buy either an ER holder or 1/4" and 3/8 holders.

It is definitely a product on my wish list.

And, a full ATC system with his stuff is something we can do, and it eliminates the problems of more stress on the motor bearings.

Dave
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  #13  
Old Wed 31 October 2007, 08:55
Marc Shlaes
Just call me: Marc
 
Cleveland, OH
United States of America
Send a message via Skype™ to Marc Shlaes
Dave,

When my machine is done, I would love to have an ATC. One thing I want to use the MM for is to cut half-blind dovetails in the flat. I know that this is a "psuedo-dovetail" but, as I stated in another thread, that is definitely good enough for me. An ATC makes that much, much simpler. I haven't seen this ATC design until now. I don't consider $90 expensive considering what the alternatives are. Do you think that there would be a way to organize a group buy?

I, like many newbies, expect to use the PC-7518 router. I assume that the "chuck" works for that machine.

This approach, provided the slipping has been corrected with the new design would be very simple to implement indeed.

Additional thoughts?
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  #14  
Old Wed 31 October 2007, 09:53
driller
Just call me:
 
I am finishing up a CNC conversion to my mini-mill, just need to put on the end switches and wires to the motors. real close.

once that is done, I plan on making my own spindle for the mill that will use the BT-30 taper. This is close to the R8 taper in dimensions.

Once that is done, I already have the HyTech holder and 8 bits for my MechMate. The MechMate will be next summers project. just getting all sorts of details lined up now.

I tend to get real lucky. since I know I'll need the steel, I will probably find great prices or perfect scrap pieces in the next 6 months. : )


Dave
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  #15  
Old Wed 31 October 2007, 09:59
driller
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Quote:
Originally Posted by Marc Shlaes View Post
Dave,

<snip>

I, like many newbies, expect to use the PC-7518 router. I assume that the "chuck" works for that machine.

This approach, provided the slipping has been corrected with the new design would be very simple to implement indeed.

Additional thoughts?

I think the slippage has been fixed.

and the cost will most likely be $199 for the holder and one or two collet chucks. each collet chuck is about $90. Still not a bad deal, especially for a machine like this.

Dave
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  #16  
Old Wed 31 October 2007, 13:07
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Apparently you need a PC-7518 with a hole right through its middle - this is not DIY retro-fit stuff.
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  #17  
Old Wed 31 October 2007, 14:30
domino11
Just call me: Heath
 
Cornwall, Ontario
Canada
Gerald,
The High Tech Systems changer they are talking about uses a spring loaded collet holder. It can be used in any router with their 1/2 inch router adapter. I have seen one in person and they do work well, although not rated for full router speeds (10K max I believe).

The porter cable solution you speak of I have seen on the web and that one does use a pneumatically actuated drawbar that extends though the router. You need to have the modified router for this system as well as the pneumatic support system as well. This solution is a lot pricier.

I suppose it depends on how much bit changing you do and what production levels you are working to.

Does Camcraft use any type of quick change or autochanger type equipment? They could surely benefit from it?
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  #18  
Old Wed 31 October 2007, 15:55
garyc
Just call me: Garyc
 
Charlotte, North Carolina
United States of America
I am in for a group buy!, I emailed him a couple of months ago and he said that he had to get some money together before he could make any more. That did not sound to promising to me ,but if enough of us get together maybe he will be willing to make at least that quantity.
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  #19  
Old Wed 31 October 2007, 16:08
Marc Shlaes
Just call me: Marc
 
Cleveland, OH
United States of America
Send a message via Skype™ to Marc Shlaes
The only thing that concerns me is the max speed. I read it on the web site and Heath (domino11) pointed it out a couple of posts ago. I believe that it was engineered for mills not routers as the very lowest speed on the 7518 is 10,000.

Anyone with more actual experience with the device???
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  #20  
Old Wed 31 October 2007, 18:43
domino11
Just call me: Heath
 
Cornwall, Ontario
Canada
Marc,
I know of a fellow that built his own wood router (a joecnc2006) and uses one of the hightechllc changers in his setup with a hitachi router. He has the older version and keeps the rpms down to 10 or 12k. He really likes it and uses it for all his work. It does limit you to the max speed you can use but for most cutting jobs, maybe its not an issue. You could always go back to manual changes for the times you need the high rpms? Just a thought.

If I could afford the pneumatic porter cable solution Gerald was talking about that would be the way to go, except for the air lines you would now need as well.
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  #21  
Old Wed 31 October 2007, 19:00
driller
Just call me:
 
The one I have has a decent fit but the slipping ring is not NASA precision. Great for my mini-mill, but at high speeds it will wobble.

Also, the spring is a simple coil spring. since those are not precision balanced for high speed, that too limits the speed.

and lastly, it has steel balls. at higher speed it's balls will fly apart or loosten on the pin. He increased the spring pressure because of that.

Dave
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  #22  
Old Thu 01 November 2007, 00:52
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
If the device fits to a standard router (un-drilled), then how long does it get below the bottom bearing? Anything that moves the cutter load further away from the bottom bearing is a bad idea - period. When you tell me it is further away and a "clickable" attachment, then that is a very bad idea - period, period.

Has anybody stuck their neck out and given these things a safety rating?

I am promoting the MechMate as a machine to profile cut boards. It is at its most profitable when one cutter can be used to do a full sheet. It gives its best quality when the z-axis is short. When quickly slicing a board into shapes, the cutter takes plenty of load, close to its breaking point. I see any quick-change tool device for the DIY router market as something that is going to extend the time for slicing up a board, de-grade cut quality, and probably injure somebody at some time.
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  #23  
Old Thu 01 November 2007, 05:50
Marc Shlaes
Just call me: Marc
 
Cleveland, OH
United States of America
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All very good points. Food for thought.
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  #24  
Old Thu 01 November 2007, 15:12
WTI
Just call me: James
 
Detroit (Michigan)
United States of America
All good points, G.

A 1/4" roundover bit is what would be convenient to do our edges, before the part is cut completely free from the sheet. That's where a tool changer would be a nice add on.
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  #25  
Old Thu 01 November 2007, 23:48
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
James, I hate break this news to you, but 1/4" roundover on a CNC router is slower than on a plain old router table. . . . . .

The snag is to control the depth (z-direction) exactly according to the top surface of the material. The factors that creep in:
- setting the tool height to a point (wing) on the cutter that is not right at the bottom.
- table must be perfectly flat
- not even one chip of sawdust between material and table, or else the cutter digs too deep.
- material must be totally consistent in thickness, all over the whole board.

A hand-fed router table, with a bearing on top of the cutter, solves all of these issues.

If you do go for roundovers on the CNC table, pull the cutter wings a little higher up - it is easier to sand that last bit, rather than to sand out a gouge. Bigger roundover radii are easier to work with.
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  #26  
Old Fri 02 November 2007, 05:56
Marc Shlaes
Just call me: Marc
 
Cleveland, OH
United States of America
Send a message via Skype™ to Marc Shlaes
To that end, long ago I bought a PC laminate trimmer and keep a 1/4" roundover bit set up perfectly in it all the time. I have about 15 routers (including 3 laminate trimmers). About 7 of them are set-up to do a specific job. I found that these were very good investments. I expect some of that need to go away but not all.

Gerald,

You are so full of practical advise. That is what I appreciate the most.
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  #27  
Old Fri 02 November 2007, 11:43
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Marc, giving honest advice is easy when you are not trying to sell something. If I were selling plans for the MechMate, would I tell you that other tools do the job better?
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  #28  
Old Sat 03 November 2007, 01:37
Alan_c
Just call me: Alan (#11)
 
Cape Town (Western Cape)
South Africa
Send a message via Skype™ to Alan_c
Yes you probably would because that's what builds confidence in you and your product,... and also because you are that type of guy.

In my daily dealings with big industrial machine suppliers, I would be much more inclined to use a supplier that gave me honest advice as apposed to just trying to make the sale - you soon see through the scheisters.
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  #29  
Old Sat 03 November 2007, 02:27
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Hey Alan, you run a big factory with a couple of $$$CNC machines$$$ - what's your take on:
- rounding over on a cnc
- auto tool changers for plain (gewone) routers?

(For those that don't know this modest Alan bloke, he is the technical manager for this company)
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  #30  
Old Sat 03 November 2007, 03:12
Alan_c
Just call me: Alan (#11)
 
Cape Town (Western Cape)
South Africa
Send a message via Skype™ to Alan_c
Doing a roundover on a cnc is APITA due to time and the vertical position as Gerald mentioned before. If I have to do it I have found the following approach best - but only because of our volumes.

We make wooden toilet seats (lots of them) daily. This is cut from a laminated board that is not always exactly the correct thickness and has a radius (15mm) all around the top surface of both the seat and lid. To overcome the problem of either cutting too deep which leaves an ugly gouge that is difficult to sand out (doing 300 sets a day = sanding time of less than a minute a piece) or not cutting deep enough which leaves a truncated radius, I had a special cutter made that flares up at the top (flat section) of the radius which gives me more tolerance on the thickness of the material.

Of course one still has to do first off samples and watch what the machine is producing - just because the machine is computer controlled does not mean it can think on its own - its only as clever (or dumb) as the operator/programmer.

On our MDF range we also do a small radius on the bottom edge of the seats, this we do on a seperate table router - it's just so fast and convenient and its done in process time while the CNC is cutting - can't have the operator picking his nose now can we?

With regards to auto tool changers, I would avoid them on routers that are not designed from the start to use them. The tolerences and runout variations they can introduce would be counter productive to accurate results. But then of course I am looking at it from a production point of view and it would depend on your respective requirements. I worked for some time on a machine that had no tool changer and never found it to be a major hinderence - it just made me plan better.

Knowing the forces involved in spinning a cutter at 14000 - 18000 or even 22000 rpm I want to know that the contraption holding the cutter is beyond reproach. I once had a tool holder with a large bevel cutter come out of the spindle due to a faulty tool changer, luckily it spun off the table to the left avoiding the operator and ended up cutting a gouge in the concrete floor as it spun like a top - it looked pretty impressive but was a chilling reminder of the power of a spinning tool - best to keep it in the spindle where it belongs.

Our big iron machines have sensors built into the tool changing mechanism and will not start the spindle if the tool is not securely clamped. The unit mentioned above did not have one of those sensors - hence my hesitation to use an aftermarket "attachment" tool changer that would definetly not have such safety features.

Remember though this is a hobby and we have only got this far through trying new things and attempting what others say is not possible. If you feel that you absoulutely have to have a tool changer due to your specefic requirements, try it out, just be aware of the possible pitfalls and take it up to speed slowly (from a respectable distance)
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