New Indexer

[kubotaman]

Okay I am seriously looking at purchasing the indexer. I have a question as to the two units offered by ShopBot. I know of the differences between the two units offered. I want to know if anyone out there have used or purchased the more expensive unit. If so, was the price difference, which is twice the price, worth the added expense? Would you do it again?

[pam_d_draper]

I too would like feedback on this, I make little nite stands and would like to make my own.
I have a used PRT.

Pam

[richards]

When I just looked, there were three units listed:

2-six inch units and 1-twelve inch unit.

The twelve-inch unit has an Alpha motor and Alpha stepper driver and a planetary gear box. One of the six-inch units has an Alpha motor and an Alpha stepper driver. The least expensive unit has a standard non-Alpha stepper motor. Both six-inch units have tapered-hob gear boxes.

Do a search on the Forum and then contact some of the 'botters. Some have built their own units while others have bought the indexer directly from Shopbot. Those 'botters that I've talked to have been more than willing to share their experiences.

When I experimented with a home-made indexer, one thing became very apparent: An indexer is NOT a lathe. An indexer "indexes" a part, i.e., it rotates a part so that part is correctly positioned for milling. A lathe spins the part rapidly under the cutter. In other words, if you use an indexer as a substitute for a lathe, you may find that it takes a LOT more time to do the same job. On the other hand, if you use the indexer to do the kinds of jobs that it was designed to do, it is irreplaceable.

[myxpykalix]

Following up on mikes comments...others have inserted a small lathe between the indexer and the tailstock to give them lathe functionality along with the indexer.
For me that independant axis control will open up other avenues of creativity for some ideas i have brewing in my head.
Soon you won't need to have a lathe for independant axis control as that is coming soon.

For me not knowing anything about CNC when i bought my shopbot i bought the indexer and everything all in one and so it was installed and even now i think it would be better to buy one from them that you know will work rather then to try to cobble one together, however you could put one together cheaper.

[kubotaman]

Mike, where did you obtain the info on 3 indexers? I have read about the two offered numerous times but have never seen 3 listed.

Jack what is the sourse of "Soon you won't need to have a lathe for independant axis control as that is coming soon." How soon and is the info reliable?? About what time frame are you talking about??

[myxpykalix]

Daryl,
This info comes straight from the top, the big kahuna himself. It should be in the next version of the control software however certain models may have to have an additional card for their control box. There was no specific release date slated for it but based on all the other stuff he has going on i'm sure he's not BS'ing.
BTW- this was all told to me in strict confidence and I was sworn to secrecy, so just in case anyone asks, you didn't hear it from me, and don't tell anyone else....lol

[richards]

Daryl,

http://www.shopbottools.com/accessories.htm

(#15102) 6" Rotary Indexing Head (for PRSalpha); PRICE $3,075

(#15104) 12" Rotary Indexing Head / with planetary gearhead (for PRSalpha); PRICE $5,995

(#15105) 6" Rotary Indexing Head (for PRSstandard); PRICE $2,075

[kubotaman]

Mike I've read that page and never noticed the three indexers offered! I guess I don't read as good as I thought!

Jack, what is meant by "you won't need to have a lathe for independant axis control"? Does that mean that a person will be able to use the indexer as a lathe???

[gerryv]

Daryl,

A word of caution. I didn't do my homework well enough and assumed (incorrectly as far as I've been able to determine) that the indexer could be operated directly by such user-friendly programs as Partworks/3D and Aspire.

It appears that we are currently limited to what I'll call a sub-program within the SB3 controller software which may be just fine for folks comfortable/handy with a calculator (or at least more than basic math) and a handle on working with machine code. I stand to be corrected on this certainly as I'm still struggling trying to find out exactly the whats and hows with regard to the indexer software.

The other area that I screwed up on when I bought my machine was that there are various levels of and limits to how a CNC machine does 3D. I'd assumed that a CNC router and a (metal) CNC milling machine or machining centre worked the same in terms of all the axes working simultaneously. Somewhere along the way, I got the impression that the Shopbot could not do this which as I understand it now is incorrect in that the "hardware" is, in fact, capable.

That said, my rather confused understanding at the moment is that the existing SB3 program cannot run the X, Y, and Z axis while others such as A and/or B are doing their thing. In fairness, I'm not exactly sure how much of a disadvantage this is over software that can support true, simultaneous motion in 5 or 6 axes.

This might even be a tempest in a teapot opinion from the perspective of a machine owner already comfortable with their machine and software so take it with a grain of salt but, if you're like me, new to CNC, wanting the same degree of ease-of-use and capability with the indexer option as you get with the excellent Shopbot hardware/software combination well, like me, maybe you should hold on to see if the upgrade - when it does arrive - offers major enhancements in the areas of simultaneous axis function, lathe function and, hopefully, including some expanded wizard" capability.

I tried to get around this by looking for a true 3D, 4+ simultaneous axis CAM or CAD/CAM program that speaks SB code but haven't yet found one. That may be the solution for me but I doubt that any of them, even the pricey ones would have as easy a learning curve as the SB software.

All that said, I could be inaccurate or just plain wrong on some of this so if anyone wants to chew my ear off that's fine - as long as you tell me in simple accurate terms what's right as well :-)

[Gary Campbell]

You guys may want to look on the Vectric Website. It appears that they now have some abilities to output to rotary axes.
Gary

[gerryv]

Good point Gary, it's my understanding that both Partworks 3D and Vectric Cut 3D allow you to do 2 and 4 sided cutting where side 1 is cut, rotate to side 2 and cut, etc. Not simultaneous, or equal to what CNC mills typically do but, no doubt, fine for what a lot of people need and the benefit of a direct, user-friendly interface.

[myxpykalix]

Let me back up a bit. Before I got a shopbot i had a legacy ornamental mill which in essence is a poor mans manual shopbot.

So if i was making a spindle or baluster with my bit in the router i manually lower it to the surface of material and lock the depth on the router there. Then i measure whatever depth I want on the depth bar, lock it off.
Then the mill turns the stock while i manually lower the bit into the material till it stops.

I have found that with different bits i can create several different designs freehand "on the fly".

And when i bought my shopbot and indexer i too thought you could control it manually similar to this. With independant axis control (coming soon) I think you will see new and creative ways for us to be able to use the indexer.

Daryl...what i meant was, some guys to get independant axis control (B spins while you move x,y,z)have inserted a small lathe between the indexer head and tailstock
http://www.talkshopbot.com/forum/messages/33571/43053.html?1245897845
and soon that manual shortcut will not be necessary as this will be controlled within the software (with a small controller card upgrade on some models).

[myxpykalix]

daryl,
"Does that mean that a person will be able to use the indexer as a lathe???"

I don't believe you will be able to spin it like a lathe at those speeds to be able to put a toolrest up and put a chisel to the work but you will be able to spin the work while moving the x,y,z manually

[cabnet636]

like gary has said, vectric has announced that the rotary function will be on the next release of aspire and vcarve, there will be more on this a t the pittsburg and dallas camps

[gerryv]

good point Jack. Based on my experience with a metal type mill and tooling, I don't see having to spin at lathe speeds as a necessity in many cases, as long as I can cut with the side of the cutter rather than the end. I find that the finish when using the end of an end cutter, regardless of how many flutes, really sucks as compared to what you get side-cutting, even with high end milling machines.

[gerryv]

Daryl, do you want this to revert back to your original question which I know you've been trying to get answered before?

[gerryv]

Thanks for the info James, I had emailed them just a few days ago about this capability and their response did not allude to this at all. It will be nice to see what's new!

[jseiler]

I didn't see anything on their website about this. Interesting.

[tmerrill]

It is buried in a long thread in the Hardware section. Here is what Brian said:

"Vectric and wrapped toolpaths

We have been following these discussions with a great deal of interest. When Greg visited Vectric a good while ago he was very keen on wrapped output from VCP / Aspire, as have a number of other individual and OEM customers. We have supported wrapped output of toolpaths from a particular OEM version of VCP for over 12 months but I have always worried about the lack of ‘ease of use’ as we can’t preview the result of the wrapped toolpath. This was not a problem for the OEM version as it was mainly diamond drag / very shallow engraving. We have always strived with the Vectric product range to produce software which is easy to use and also allows the user to visualise their results before they ever cut it on the CNC. Unfortunately with wrapped toolpath output this visualisation capability is lost. However the enthusiasm which has been shown for wrapped output on this thread has convinced me to change my mind and I have added the wrapped toolpath output option to the next version of VCP / Aspire (this will be a free upgrade for existing users as it will me a ‘minor’ point release). We are currently Beta testing and hope to be able to release about the time of the user groups.
Brian"

[cabnet636]

sorry info already posted

jim

[eaglesplsh]

Anyone willing to confirm/deny Gerald's comments on the ability to move 4 axis at the same time?

At the moment, my indexer is still a box of parts waiting to be assembled, so I don't have first hand experience myself.

At the annual Shopbot gathering in Texas last fall, Scott Cox gave a talk on designing parts for the indexer/wrapping parts onto a 4th axis. As I recall, his samples may have used all 4 axis at the same time.

Also, there is are M4 and M5 commands shown in the Command Reference Guide:

M4 - Move 4 Dimensions
{x-location/distance, y-location/distance, z-location/distance, a-location/distance}
Makes an X, Y, Z, and A axis move to the designated location or a specified distance (if in Relative Mode) at current Move or cutting speed. These 3-D interpolated moves are made on a diagonal from the current location to the end location indicated in the location/distance values, which may be absolute or relative depending on the Move Mode setting. If a value is not entered for one of the parameters, the value defaults to the current location assuming a comma is used as a spacer to designate the correct parameter field.

[rnels]

I have ShopBot's indexer. I use M5 commands. With the indexer being the B or 5th element in the M5 string.

Example 1: (very simplified)

If your indexer is oriented along the X axis you would have the Y values for the whole ShopBot part file at 0 as you want to maintain a straight line down Y to stay in the middle of the blank. You would then be able to use the other 3 axis for additional positioning - X along the length of the blank, Z for positioning the depth of cut, and B for positioning the desired rotation. A is always 0 for me as I only use B.

Using a pre-rounded blank:

'M5,X,Y,Z,A,B

VD,,5 'Set display to 5 axis
VS,,,,720 'Set indexer speed - play with to see what works best.

J5,2,0,1,0,0 'Position at 2 inches in X and safez of 1 inch above blank at zero rotation.

'Demo purposes only assuming Z zeroed to top of
'blank - ShopBot uses center of blank
'so there would only be positive Z numbers.

M5,2,0,-.1,0,0 'Same X position move -.1 in Z (depth) at 0 rotation.

M5,2,0,-.1,0,360 'Same X position and Z depth rotate 360 degrees leaving a .1 inch ring around the whole blank. Very simplified you would probably want to rotate more times around to get a cleaner ring.

MZ,1 'raise Z to safez
MB,0 'reset for next command or ZB if you are using 360 degree increments.

Example 2:

You want to carve a whole relief on one side of a square blank then rotate to the next and do the same.

Zero on your blank as if you were carving without the indexer. I use X 0, Y 0 lower left hand corner of my model. If your model was 2 inches high by 6 inches long you would need a blank that was 2 inches square by maybe 8 inches long to allow a little extra on the headstock and tailstock ends (extra length is optional). So I would zero the X about 1 inch from the headstock end and Y at the edge of the blank.

'M5,X,Y,Z,A,B

VD,,5 'Set display to 5 axis
VS,,,,720 'Set indexer speed

M5,X,Y,Z,0,0 'All of your SBP code for your relief at 0 rotation.

etc.,0,0
etc.,0,0

When done with side 1 make sure your safeZ is higher than the edges as they rotate around to side 2.

MZ,2 'hypothetical just make sure high enough.

MB,90 'rotate 90 degrees to side 2.
J2,0,0 'reposition to your XY zero.

M5,X,Y,Z,0,90 'All of your SBP code for your relief at 90 rotation. Indexer will stay at side 2 or 90 degrees and not move allowing your relief to carve on this side as long as all M5 etc. commands have 90 in the B position.

etc.,0,90
etc.,0,90

Simplified - The software that wraps the file (model) for the indexer would convert the Y distances (for indexers in the X orientation) to B rotational values so the indexer would rotate to the specific Y value in degrees (distance?) around the blank.

[kubotaman]

I certainly don't want to be rude but does anyone have first hand knowledge about the 12" indexer like I had originally asked???

[scottcox]

Daryl,

I have one of the 12" 25/1 planetary setups. I'm VERY happy with the way the hardware has performed. It's a robust piece and when you have your tracks aligned right, it is dead-on accurate, every time. I have a 16" dia. x 10ft range for my indexer and have turned a log that was at least 100 pounds (seemed like it). You just don't want to spin it too fast.

I milled my own full length aluminum t-rack for the indexer, btw.

From the get-go, the software has been the limiting factor for the indexer, but that's changing. There really are MANY ways to program files for it, some easier than others.

[kubotaman]

Scott, thanks for the reply. You are the first one that I know that has the 12" indexer. Why did you buy it over the 6"? It is quite a bit of difference in price. You must have the 12" axis also since you can do 16's". I also have the 12"axis. Would you buy it again and do you do many large turnings?

[scottcox]

My thought was that bigger is better and I have no regrets. I've cut some rather large pieces and still wish I had more range.

I custom built a 5'x10' steel table with a 16" wide "trough" along one side parallel to the x axis. I centered the indexer at about the table surface, so I have about 8" of Z travel, hence 16" diameter.

[myxpykalix]

My table is based on the same plans as Scotts however my indexer is mounted below the surface level of the table and my Z will extend below my 0 center of the indexer and i don't seem to have a problem.

Scott...the bottom of the trough is about 12" deep so you would have had to elevate your aluminum track above that bottom, how did you do that?

[scottcox]

My trough is 10" deep from steel to steel. I have shims and the t-track in it equaling about 2". From the top of the t-track to the 25/1 indexer center is "almost" 10". And I have about 2 inches of table surface shims and material.

I wish I had more Z travel. I've had to relocate my spindle up and down the z-plate to use longer or shorter bits. I often machine flat stuff down in the trough, using the t-track as a hold-down for jigs. I also machine really thick stuff up on the table, calling for shorter bits.

The versitility of thing still astounds me.