[BlueFin]

How much would one be willing to pay to automate the 2-3 manual revolutions of the drawbar? Does the buyer already have a dry air access or is that investment on top?

It does not (hardly) accelerate the tool change process and it does definitely not automate it. It is probably just a first step on a long journey to an ATC.

Benji

What is this worth???? Oh my god! Whatever they are going to ask for a price it is worth 10 times that amount. All you do is push a button, pull out a TTS, place another one in and then hit cycle start and run your next tool. I machine parts when I get home from my real job, I can hear the machine shut down in the garage when I am eating dinner. I have to run out there and go through the whole door opening, wrench turning, spindle lock crap before I can get back to my Enchiladas and Rice. Being CNC machine owners and part designers there is nothing there that any one of us couldn't design and fabricate, but do you have the time? I don't right now (and that's a good thing, cause it means I still have a job)

There are really only a few ways to do something like this and we have all seen Hoss's video of his, but I do not like pushing down with all that force on bearings of any kind let alone precision ones. So the pinching idea has been a priority since day one, here is a post and a drawing from me back in January where I was toying with the idea of pinching the spindle in the same exact manner while allowing the drawbar mechanism to float like Tormach's.

http://www.cnczone.com/forums/showth...138#post559138

I was and still would be interested in using hydraulic force rather than air pressure, but that is just a matter of personal preference. I didn't understand pancake cylinders until now, so I may change my ways soon. Those are pretty cool. You will see in the post that I changed my idea from the drawing to something else that is more compact (even more than Tormach's) but a single OEM part in my design cost over $250.00 I was trying to have a system for under $1K, and it became hard to do with the purchase of that one needed part. And that makes it hard to sell to people who do not share my obsession with just pushing a button to change a tool.

[philbur]

I don't think you can use it with R8 tooling. The Collet/toolholder stays in place when you operate the drawbar.

I'm interested to know if they have pinned the drawbar to the collet in some way, otherwise any small rotation of the DB during repeated operation will alter the "as set" tension on the belville springs washers.

Phil

It is an elegant design, it allows the use of the tormach tooling or any r-8 as well ......

[benji2505]

The parts we make on our PCNCII run for about 60 minutes and they have 3, maybe 4 tool changes. I doubt one gains more than 30 seconds per tool change, that is 2 minutes overall or less than 5%.

Somebody still has to go to the machine, pull out the new tool, do the change, put the used tool back ..... and wash his/her hands before going back to enchiladas and rice.

I would not be surprised if Tormach does not even launch that product as a is, but waits until they have a complete ATC solution integrated into the control.

Benji

[Don Clement]

I didn't understand pancake cylinders until now, so I may change my ways soon. Those are pretty cool. You will see in the post that I changed my idea from the drawing to something else that is more compact (even more than Tormach's) but a single OEM part in my design cost over $250.00 I was trying to have a system for under $1K, and it became hard to do with the purchase of that one needed part. And that makes it hard to sell to people who do not share my obsession with just pushing a button to change a tool.

I spent >$2K for a Royal Pneumatic 5C closer for my lathe. http://www.royalprod.com/product.cfm?catID=3&id=20 One of the best investments I ever made. An effortless push on the air control valve lever closes the collet and a reverse push of the air control valve lever opens the collet and actually pushes the collet open. (no more banging on the drawbar with a shot-filled mallet) Because of the direct double-acting air piston, a huge advantage of the pneumatic closer is the collet closing force is proportional to air pressure and directly controlled by a differential pressure valve. This means I can control exactly and repeatably how much force is on the collet by setting the value on the differential pressure valve. The pneumatic closer is particularly useful in holding thin walled Turcite parts for machining without distortion. The Royal Pneumatic 5C closer is also a floating type with its own set of bearings so the lathe spindle bearings are not effected.
I welcome a design for a similar type closer for the Tormach.

[sharpshooter90]

That's absolutely classic! The same guys who jumped in and started re-designing Scotts ATC last year are now going at the Tormach version. The Tormach guys are pretty smart, and I doubt that any of this talk will deter them from their plan. They have done an impressive job in recognizing a niche market and cornering it. Browsing through Importgenius.com, you can see that even though their volume is only about 1/2 of what it was a few years back, they are doing 10X the business Smithy and Syil are doing in the CNC mills . Speaking of Smithy, I noticed an unusual note on their import bills of lading. Their 1324 and 1340 machines are classified as " Used".

[philbur]

Many people put powered drawbars on their bridgeports and on their ... etc etc. but no ATC. One could also question the need for the TTS when a solid R8 toolholder takes only a few seconds longer to change out. Do I think my investment in the TTS was a good idea, you bet ya.

Phil

The parts we make on our PCNCII run for about 60 minutes and they have 3, maybe 4 tool changes. I doubt one gains more than 30 seconds per tool change, that is 2 minutes overall or less than 5%.

Somebody still has to go to the machine, pull out the new tool, do the change, put the used tool back ..... and wash his/her hands before going back to enchiladas and rice.

I would not be surprised if Tormach does not even launch that product as a is, but waits until they have a complete ATC solution integrated into the control.

Benji

[Don Clement]

Many people put powered drawbars on their bridgeports and on their ... etc etc. but no ATC. One could also question the need for the TTS when a solid R8 toolholder takes only a few seconds longer to change out. Do I think my investment in the TTS was a good idea, you bet ya.

Phil

The solid R8 toolholders do not have the repeatable height that the double contact TTS have.

[philbur]

Good point, but I think if you make the effort you can come pretty close. Also I think R8's have the possibility to do better on radial runout repeatability.

Phil

The solid R8 toolholders do not have the repeatable height that the double contact TTS have.

[Don Clement]

Good point, but I think if you make the effort you can come pretty close. Also I think R8's have the possibility to do better on radial runout repeatability.

Phil

What's pretty close? Do you have the data? Also TTS take much less travel to remove than an R8.

[Bubba]

Just to add fuel to the fire of why someone might want/need a power draw bar option would be due to physical problems. Some might be short enough that they need an assist to get up high enough to make the change and I have seen some on various boards that are physically challenged in different ways. For these people, it gives them a chance to enjoy our hobby that might otherwise be difficult if not impossible.

[sharpshooter90]

I still am waiting to see anything he has done, to date nothing.......

scott

Here is a little project- nothing high tech or fancy, but it saved quite a bit of money in a short time.

http://www.cnczone.com/forums/showth...330#post661330

[BobWarfield]

What's pretty close? Do you have the data? Also TTS take much less travel to remove than an R8.

Sure, I've got data. My solid R8 holders repeat to 5 tenths or less.

Cheers,

BW

[benji2505]

0.05 inches is pretty big. You probably have to touch off the tool each time you use it, right?

Repeatability with TTS System is below .001 in all three dimension for us (in the moment). No need for touching off tools regularly. We are not experiencing significant runouts.

Benji

[Don Clement]

By 5 tenths do you mean 1/2 mill? Does anyone make an R8 fixture to measure height on the surface plate ala Tormach TTS fixure? One still has to unscew the R8 toolholder and have about 3" of clearance to change R8 toolholders. TTS only need an inch or so and only need to loosen the 3/4" R8 collet, not totally unscrew it. For my purposes the TTS works way better for changeing toolholders than a solid R8. YMMV

[Bubba]

When BW was refering to 5 tenths, it means 0.0005"

0.05= Fifty thou. and 1/2= 0.5= 5 hundred thou.

[benji2505]

When BW was refering to 5 tenths, it means 0.0005"

0.05= Fifty thou. and 1/2= 0.5= 5 hundred thou.

Yup, the moment I sent away my comment it struck me. 50 thou would have been a little too much

[BobWarfield]

When BW was refering to 5 tenths, it means 0.0005"

0.05= Fifty thou. and 1/2= 0.5= 5 hundred thou.

Thanks Bubba!

RE a calibration fixture, I use a Z-axis presetter:



I got mine from 800watt on eBay. They're accurate and easy to use. You could also make a very simple touchplate to work with a Mach3 macro, and I will eventually get around to that.

Choose a "reference" tool. Measure its height. Make that 0 in the tool offsets. Now measure the rest of them and enter the differences.

I keep my tool table organized to match the holder positions in my rack:



Now all the tool heights are ready to go and repeatable. Tool changes are very fast.

Cheers,

BW

[norvil1]

I am not disapproving this development or the design.

I am only questioning the "value added".

Benji

then don't buy it.;

[Don Clement]

Bob,

I can’t use your presetting tool for setting up on an angle plate. On the angle plate I use a ½” diameter roll pin resting against the front of the part and the bottom of the angle plate. Alternatively a tooling ball could be used in place of the roll pin. The highest point of the roll pin is measured and the Z-axis datum is calculated. The # 1 TDI tool is used to measure the highest point on the roll pin and also is used to set the Z-axis datum on flat surfaces. Here is a picture of the #1 TDI tool: http://i72.photobucket.com/albums/i1...ettToolNo1.jpg
I measure the height all of my TTS tools, including the TDI tool #1 using Tormach’s TTS Measurement Fixture (30140) http://www.tormach.com/Product_TTS_measurement.html on the surface plate and enter height value in the tool table. All that is needed then is to use the TDI tool #1 set to the place where the Z-axis datum is and zero the Z-axis on the Mach III screen. BTW tool #1 is set to 0.05” deflection on the surface plate and when setting the Z-axis datum. All tool table values are now set for the measured Z-axis datum. The #1 TDI tool only works for TTS toolholders but if a calibration fixture similar to the Tormach TTS Measurement Fixture (30140) were available for R8 toolholders then this method would also work for R8 toolholders. (that is if R8 toolholders really do have the claimed height repeatability without the double contact as the TTS holder have)

[BobWarfield]

Keep in mind, Don, you wouldn't need to do it the Tormach way (though you can). First, you can use a presetter (or a touch plate is cheaper, faster, easier) to determine the tool offsets right on the mill relative to tool #1.

Then your issue is to use tool #1 relative to the work. It's trivial to create a tool like the plunger indicator you show. You could use a DTI as well.

Or you could use a touch probe there too. I have modified an edgefinder that I like to use, and may just make it the #1 tool now that I think of it.

An electronic touch probe would be really fast and could line up on sine bar fixture as well.

So if you haven't spent a bunch on the TTS, what do you really need?

- Your R8 tooling

- A presetter or other means of measuring tool height on the mill. IH shows how to make a presetter from a dial gage. A touch pad that connects to a Mach3 macro would probably be the ultimate in cheap and cheerful. When you build your ATC, you can set it up to automatically measure the height of every tool in the carousel with a Mach 3 macro.

- A #1 tool that is appropriate to your jobs. For me, it had been a 1/2" endmill. I can see where to line up on your sine plate, something else would work better. I like the idea of an edgefinding probe linked to Mach 3.

Start a job by inserting the #1 tool and setting tool height for your workpiece (or see my recent blog post about basing your tool heights on your workholding rather than your workpiece: www.cnccookbook.com).

Place the first tool required for your job in the spindle. The tool table is already set up. Hit run and off she goes.

Cheers,

BW