[Don Clement]

"Price of CAM software to actually spit out 5th axis g-code: priceless (ok, just $12k, but might as well be priceless)"

Ignorance is bliss to a troll. I got my SprutCAM for ~$1k because I bought it with my Tormach 1100 and Tormach 8" rotary table. And yes priceless @$1K which is $11k saved. If this thread is about saving money on 4th and 5th axis that is almost useless without an affordable CAM program unless one is just indexing then just write the G-code without cam. Fortunately Tormach offers a way to save BIG money on 4th and 5th axis continuous capable SprutCAM when buying their products. So you saved $1.4K on that RT and still have to convert to CNC and then have to spend an additional $12K for that CAM package to run it.

Don Clement

[acannell]

So anyway, what would be a good choice for a motor to turn the table?

Im not sure how much torque it needs to have.

-if you just use it for prepositioning, then maybe it only needs to handle turning the table, and you can count on the worm gear friction and/or manual clamps for holding torque during cutting

-if its to turn while cutting, then you need to figure out maximum cutting forces, which can vary wildly depending on what you are planning on. Assuming worst case would be a cut at the edge of the table (or edge of the work, if it goes beyond).

So some kind of prediction of what you would use the table for would seem to be in order.

Or another way to look at it would be: whats the biggest motor you can fit without increasing size, weight, and cost too much? I think I'm a fan of that option.

So steppers or brushless servomotor?

What about speed: It seems like the fastest I can turn it by hand is about 3rpm (the table). I wouldnt want to go much faster than that CNC because I'm not sure if the design would handle it as far as maintaining oil and getting hot or wearing much faster for some reason.

3rpm is 1080 degrees per minute. One rev of the handwheel is 4 degrees. So 270 turns for 1080 degrees. So 270 rpm. That may be in the ballpark for a stepper, as well as a brushless. I'd like to avoid a pulley system and it seems Tormach got away without one too.

So direct drive, 270 rpm, and how much torque? If we say we want..arbitrarily, 30 lbs of force at the edge of the 6" table, that comes out to 15 foot lbs of torque. Divided by 90 is 0.166 ft lbs, or 2 in. lbs.

But is 30lbs enough force?

[JRouche]

Hey Doc. Good to see this project is still alive. I have accumulated a few 6" rotary tables just for this purpose. Ill be following along.. JR

[acannell]

Hey Doc. Good to see this project is still alive. I have accumulated a few 6" rotary tables just for this purpose. Ill be following along.. JR

JRouche! Dont follow along, join in! Lets get a few people together that want to do rotary table CNC retrofitting, start a thread, and brainstorm about motors and motor brackets. I am by no means an expert. Are you in? Lets see if we can get 5 people total..theres you, me, and then we need three more. Hopefully people that already have a rotary table and are serious about converting it like NOW. Its like one of those makeup parties girls have except its a rotary table CNC conversion workshop.

[acannell]

I use HSMWorks. 5th axis is only available on the Premium version, which costs $11500. Just because you have cheap CAM software doesn't make my comment trolling.

You want to see the picture if my Tormach 1100 in my garage?

I see why this forum gets a bad rap.

tmarks11: whats it going to take to convince you to drop all your other projects and convert a rotary table to CNC with me and Jrouche??

[acannell]

I use HSMWorks. 5th axis is only available on the Premium version, which costs $11500.
Attachment 252976

Wow I'm jealous of the newness of that mill.....hopefully its alot dirtier by now

[tmarks11]

Yep, it is a bit dirty now.

There are quite a few threads on cnczone on converting rotary tables. A short search turns up a number of discussions of phase II 6" conversions. I am almost even thinking of a 4", mostly for the convenience of moving less weight on and off the table. I think mostly I would be working with 1" and 2" diameter pieces, so I don't think the smaller chuck capability would be an issue.

I already have an 8" phase II rotary, and that thing is a monster to move around, I thought about converting it, but it mostly lives on a bottom shelf these days.

[JRouche]

JRouche! Dont follow along, join in! Lets get a few people together that want to do rotary table CNC retrofitting, start a thread, and brainstorm about motors and motor brackets. I am by no means an expert. Are you in? Lets see if we can get 5 people total..theres you, me, and then we need three more. Hopefully people that already have a rotary table and are serious about converting it like NOW. Its like one of those makeup parties girls have except its a rotary table CNC conversion workshop.

LOL Im afraid Lotta unhappy :boxing: folks on the thread it seems.. Ill just watch from afar for now. Good luck...... JR

[acannell]

Yep, it is a bit dirty now.

There are quite a few threads on cnczone on converting rotary tables. A short search turns up a number of discussions of phase II 6" conversions. I am almost even thinking of a 4", mostly for the convenience of moving less weight on and off the table. I think mostly I would be working with 1" and 2" diameter pieces, so I don't think the smaller chuck capability would be an issue.

I already have an 8" phase II rotary, and that thing is a monster to move around, I thought about converting it, but it mostly lives on a bottom shelf these days.

I dont blame you at all. The TSK160 weights 75 lbs and its about the max I can lift onto the mill bed.

So what kind of connections does the Tormach have for 4th axis? What are we talking about electrically? Stepper/brushless? If you have to buy a separate driver, what does that driver connect to? Some kind of motherboard?

[tmarks11]

So what kind of connections does the Tormach have for 4th axis? What are we talking about electrically? Stepper/brushless? If you have to buy a separate driver, what does that driver connect to? Some kind of motherboard?

Tormach sells the 4th axis driver as a separate accessory; their control cabinet has a space with pre-drilled holes to mount it, with a ribbon cable and plug already run from the breakout board. Pretty fool proof. Just add a leadshine MA860H stepper driver, and a NEMA23 bipolar motor for a 6" rotary table, and you are done.

The adaptor bracket from the motor to the rotary table would have to be custom built depending on what you were using a s a 4th axis. Here is a pretty good one in this video (got this off of a Hoss thread on 4th axis):
https://www.youtube.com/watch?v=2JLnW3-JX2w

[LSM]

what are you complaining about the Tormach rotary tables are inexpensive 8k is the normal range for a 4th axis in the real world.
and then you have to buy the electronics for the machine. that will run more then the price of the Tormach 4th axis kit complete
.
it all comes down to do you want to use it or spend all your time making it and calibrating it
AT $2100 for a 6" tilting with 4th axis kit is a good deal and the 8" for around $100 more get real.
it isn't worth messing around with a DIY job

[tmarks11]

what are you complaining about the Tormach rotary tables are inexpensive 8k is the normal range for a 4th axis in the real world.

Quite a bit difference in build quality between a Haas 4th axis and a converted phase II rotary table.

And I am pretty sure that at least half of the cnczone regulars are here because they "like to mess around with DIY jobs".

This is definitely not the first time DIY conversions for 4th axis have come up in the Tormach forum, and they are regular fodder in the bench top forum.

[acannell]

what are you complaining about the Tormach rotary tables are inexpensive 8k is the normal range for a 4th axis in the real world.
and then you have to buy the electronics for the machine. that will run more then the price of the Tormach 4th axis kit complete
.
it all comes down to do you want to use it or spend all your time making it and calibrating it
AT $2100 for a 6" tilting with 4th axis kit is a good deal and the 8" for around $100 more get real.
it isn't worth messing around with a DIY job

Lol its always hilarious when people on machining forums call something "DIY" or to much of a "waste of time". Meanwhile they spent thousands of dollars to have a CNC mill put in their house. Its all relative isn't it? Dont you find saying that a 4th axis CNC rotary table shouldnt be "DIY", on CNCZONE, is obviously and immediately absurd and ironic?

And I'm a bit disappointed so many of you seem to think adapting a motor to a rotary table is somehow a major undertaking. Why are you people in machining at all?

Anyways, lets get some info going here:

The Tormach operators manual for the 4th axis: Direct Document and Software Download | Tormach LLC providers of personal small CNC machines, CNC tooling, and many more CNC items.

VERY good read. In fact, this makes a MUCH MUCH better manual for the TSK160 than the Chinese one, no surprise. Especially as to details about oiling and adjustments.

Also, there are detailed specs for pretty much every aspect of Tormachs 4th axis.

Including an exploded view ..does that mean I can order parts for my TSK160 from Tormach in the USA? That could be interesting.

Should probably do a reality check and see how much Tormach wants for JUST the 4th axis parts..motor, brackets, drivers. tmarks11, are you sure they sell that as a kit, or is it something youd need to buy piece by piece? I thought they just sold the table + kit, or table, but not just kit.

So looks like some the motor, mouting, and coupling to the shaft are comprised of parts:

67, 68, 69, 70, 71, and 72.

Who would like to call Tormach and get some prices?

That mounting couldnt look simpler. I think they are literally using a solid coupler right to the worm gear. I forget what the worm shaft looks like with the handle off. I'll have to check and see what we're dealing with.

So what about torques and speeds:

Looks like they spec 264oz/in of holding torque for the 6" table. So thats 16.5 lb/in. Times 90 is 1485 lb/in. At 3 inches its 495 lbs. So lets say thats our design spec for torque/motor selection.

Minimum step, microstepping, is 1.2 arc minutes. If I am correct that equates to 0.00017 inches at the periphery of the 6" table. Sounds good to me.

[acannell]

okay part 69, the motor coupling, is $25.65

Tormach LLC

And I was wrong its not solid, duh. They show it in the manual as the usual split/helix style.

Heres my TSK160 with the handle off...

and then with the vernier off.

The center shaft with the key is the worm.

Looks like you could mount a motor to the 4 holes in the outer sleeve, the use the clamp for the sleeve to lock it in place, and couple motor the motor to the central shaft. Voila.

By releasing the lever, you would make it possible to rotate the motor to an arbitrary angle if needed, could be useful somehow.

I think I have a nema 23 stepper motor actually. But I dont think my mill will work with a stepper, it wants a brushless. Hmm..

I should note all the sliding surfaces on the vernier and even the handwheel appear ground...not too shabby

[acannell]

derp...

by removing the clamp quite a few more parts come off..

now we're really at the base level... that stump with the 4 holes is actually part of the eccentric shaft so you cant , nor would you want, to remove it.

As far as I know, according to my manual, the backlash is maintained by the two special nuts behind that precision washer, so that isnt something that needs to be worried about.

so you could mount your motor bracket directly to that. if you look at the pictures of the Tormach table you can tell thats how they mount theirs, and its pretty obviously the most logical point.

At this point, there really isnt anything to the design of the mount. Pick your coupler. Use the hole pattern on the motor and on the table mount. Make a space. Thats it.

For anyone who actually owns a tormach, machining something like this is a total non event. Designing it in Solidworks would be a fun afternoon.

Imma see if I can somehow use the stepper motors I already have, and if so, things are going to get real REALLY FAST.

Otherwise Im going to have to scrounge around on flea bay for a cheap brushless motor w/encoder which fits the bill.

[ger21]

If your tormach is running Mach3, then it's most likely just outputting step and direction signals, so you should be able to use any type of motor you want.

[acannell]

okay my MDP2231-4 MDRIVE motor with encoder...actually I forget if it does or not, it has an integrated drive and its hard to tell

Well anyways, its got 239 oz/in of torque which is 90% of the Tormach, and its definitely small. Come to think of it this may not really be that expensive of a motor..so it may be worth just buying one that has an encoder, because Im not sure how I could incorporate an encoder into this one since the shaft is so short.

[acannell]

heres an ebay NEMA 23 leadshine stepper motor with 2nm of torque (thats about the same as the Tormach), and it has a 1000 line encoder

$149

NEMA 23 Leadshine 2 Phase Stepper Motor 57HS20 EC 1000 2 0nm 1000 Line Encoder | eBay

[Windscreen]

acannell,

Did yours come with 0.47" keys like Utoole shows, or 0.55" keys like Tormach shows?

-Steve

[acannell]

acannell,

Did yours come with 0.47" keys like Utoole shows, or 0.55" keys like Tormach shows?

-Steve

Mine are 0.47". Are you thinking of getting one of these?

IMO it would be neat to use the keys and get perfect squareness every time. But its kind of limiting to only be able to space the table in slots in one direction. And then you have the fact you have these hardened keys sitting on your mills bed while you try to wiggle the 75lb table into the slot...yikes...

So I just use a tenths indicator to locate the table square, just like a vise