4th Axis addition - V2XT

[NC Cams]

Want/need to add the fourth axis 'option' to a V2XT that i just bought. Version is a 1998 with the DX32 with BMDC controller card.

Short of duplicating/buying the OEM pieces/parts, has anybody done a retrofit/4th axis upgrade to a 3 axis machine?

What did you use and where did you get it short of buying off of Ebay? Need suggestions for axis/indexers (model numbers and makes).

Any advice on where to get the material for the harnesses (cable, connectors/sockets for plug-in wires on AUF and AXSBOB cards, etc)?.

I do have the factory schematics.

[RedGTZ]

I'm also looking at doing the same exact thing but with a TorqCut 22 from Bpt, the machine is like new and I would have parts to do in 4 axis once in a while but I want to keep the cost of this install as low as possible

Thanks for any inputs!

[NC Cams]

As my situation is essentially a 'retirement' project, my cost criteria is exactly the same.

Cheapest alternative I've found so far is Troyke who made the "table" for Bridgeport's 4th axis as the OEM. BPT then did their own system drive integration/packaging. BPT did not buy a pre-packaged kit as you now can do now from Haas or SMW or Troyke - but for a real co$t.

Basically, Troyke sells the table/axis and then you start adding motors, cables, drive belts, etc to them to make the full 4th axis. You have to buy your own servo amp drive too. It doesn't get inexpensive once you get a fully functioning system - hell, Troyke even charges you for the frigging cable and that isn't cheap (according to their on-line price sheet).

In your case, you have AC drives for your servo's hence you really want a "matched" amp/motor package for the 4th axis. From what I learned so far, you do NOT want to go mixed mode (AC VMC, DC 4th axis or vice versa).

ALthough AC drives are much more modern and have all the more modern advantages, they do have added comlexity. Reason: a separate path of communitication has to be established between motor and drive so as to affect proper commutation.

This is in addition to servo position feedback. This means matched motor/drive combo which surely ups the cost ante and the complexity and reduces flexibility of choice. Depending on your skill level, it may simply be outside the realm of DIY integration for you to create your own 4th axis AC system. Recall that you or someone has to tune it and tell the DX32 that it is there and do so properly.

SO far, the prices I've gotten range from $5700 (9" table only, no wiring or motor or drive) plus $1.3 to $1.8k for a motor plus the encoders plus the cabling (prices TBD) - probably $8k~$9k when it is all said and done.

Just to find the proper MIL connector that plugs into the prewired cabinet essentially turns this into a PITA project AND the schematic is NOT that easy to read/figure out regarding which pins are which on the prewired MIL connector that should be in the cabinet.

I got an $8K "estimate" for a plug and play system from Haas. But they are not at all quick in responding to my formal RFQ. And even when I sent them the schematic and all the motor and servo amp info and the controller info, they seemed reluctant to want to prewire it for me.

In light of the fact that you are probably running an AC based servo drive system on your machine, you're options for an aftermarket system are more limited than mine (DC system on V2XT with prewired cabinet).

Even so, I"m learning that adding a 4th axis drive to anything that is of a "legacy" device such as our units turns into anything but fun and games.

I can't wait to see what fun is in store for me with my "4th axis, the DX32 software automatically recognizes that is there" when/if I get a 4th axis. Is there any reason why I should dream/hope this will happen???

[machintek]

Careful. The Torque cut 22 had DC motors. SEM on X and Y and a PARVEX on the Z. Spindle drive was Yaskawa AC type.
The TC1,2,3, and 4 had the Yaskawa AC drives on everything.

George

[RedGTZ]

Thanks for the quick reply guys.

I dont really need sychornized 4th axis for now but rather a positioning 4th axis, would this be an easier install??

I think the project will be put aside until the next machine gets in the shop... it seems to be a real pita to get all this working right and I have only a basic knowledge of all that integration stuff.

My TC22 was prewired for the 4th axis but the drive and other components are not there so that would be a huge investment compared to the price paid for the machine...

I'll get in touch with you guys for sure if I ever decide to make this dream a reality. You seem to both have a lot knowledge with the Bpt machines

Thanks again!

[NC Cams]

The servo amp is a "cheaper" part of the project when you lay out the whole cost factor.

Motion Science and Advance Motion Controls sell brush type DC servo amps that will readily work pretty much as bolt ins. The AMC's are between $350 and $395 each and they should bolt up to the appropriate wires that are already in the cabinet.

The axis hardware along with the cable from the axis to the power cabinet are the pricey items however.

Sorry about the bogus info on the DC vs AC for the TC22 servo motor - I was looking at the VMC 800/1000 wiring diagram which is AC motored.

BE REAL CAREFUL when buying used 4th axis. I've seen many that seemed like a deal - only to find out (in time luckily) that the motors are AC and I need DC.

Apparently you and I are looking for the same entity and they aren't that plentiful. For the time being, Haas still custom makes DC fitted motors but supposedly that will last until years end when they are supposed to quit.

I guess that it would not be THAT hard to change an AC motored servo over to DC from a mechanicla standpoint. However, the PITA that you'd have to go thru to get a motor, make sure it had proper encoders, and a tach could be more trouble than it is worth. Yes you can shop on Ebay but 100vdc servo motors with tachs and encoders don't seem to be at all plentiful.

My research, Machintek George's help plus advice from another tech indicate that once you have the thing wired, it is pretty much plug and play. The DX32 controller automatically senses the 4th axis and away you go.

Yes, the cabinets are "prewired" but I still can't find the wires that go from the amp to the output connector in my cabinet - I found the shunting relay but can't find the wired 'tween it and the amp. Not a biggie to run but why bother disturbing a harness if you don't have to.

My knowledge about the systems was developed as a matter of general interest in concert with a need to repair/service my mill and not having the cash on hand to simply pay to have it done. Actually, I got a bit too involved in the reverse engineering of the electronics but is has not been a waste of time and effort.

When you consider what it costs to build a V2XT versus what they want to fit it with a 4th axis, the option HAD to be a real money maker. If you take the time to study the wiring diagram and find the wires (thankfully BPT labels stuff real well), it isn't that hard to figure out what's going on.

How to find and get a deal on the axis, now that takes a real gift and/or a huge chunk of luck.

A positioning 4th axis might be easier and perhaps cheaper but for a little bit more, you can go to the full axis and be oh so much more flexible and/or precise.

As my dad told me when I was old enought to drink, "drink top shelf, it tastes better and you won't be as sick in the morning". This translates to "buy the best you can't afford, you won't be disappointed with the performance" when it comes to buying equipment for my business and/or hobby interests.

[NEATman]

machintek-
If one already had the SEM motor with encoder and the same model drive as on the V2XT, it would be straightforward to use this motor and drive a 4th axis? Does the cabinet supply the DC power needed for the amplifier? Or would I need a seperate powersupply for this additional drive?

NEATman

[NC Cams]

The DC buss on the V2XT supplies power to ALL the axis drives (100-105vdc if memory serves correct).

If the motor on the 4th axis that you're using is compatible with that voltage (SEM or whatever), it should run fine off of the V2XT power supply. If you have a4th axis motor that is a twin to the V2XT drives, you are in fat city.

There is a MIL spec connector on my V2XT that is already plumbed with the power and feedback/control circuits needed for 4th axis work.

The wires for the 4th axis amp are coiled and ready and taped to the back of another amp. When/if properly connnected and the parameters in the BMDC configuration file propely set, the 4th axis should "plug and play" if the 4th axis connector cable is appropriately and properly wired.

[RedGTZ]

Just bought my 4th axis yesterday, I had to jump on this one

I did a post about it and about the install, I'll update it as I'm going thru the whole process.

http://www.cnczone.com/forums/showth...853#post346853

Any advices? I got a lot from that thread alone so maybe you got something new to share NC Cams or Machinetek