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CuttingTools
04-29-2007, 09:39 PM
I have A cnc TAIG Mill with the 18" Table, This machine has the CNC Leadscrew nuts. I am getting backlash that I just cannot tolerate as I machine many parts that have bearing fits machined into them. Has anyone installed ball screws on the Taig mill? If so can you elaborate on the process. I am open to listening to any ideas on correcting this problem.

Scott

edferg
04-30-2007, 01:56 AM
I would ask here:
http://groups.yahoo.com/group/taigtools/

On my Taig CNC mill I get 0.003" backlash, which from reading the group, seems typical. If you are getting more than that, there are ways to isolate and fix the cause.

I've seen a couple of posts from guys who have converted Taig mills to ballscrews (search the group above). From their descriptions, it is not easy or cheap. If it was an easy retrofit I would be interested myself.

Ed

Stepper Monkey
04-30-2007, 07:40 AM
What do you consider acceptable? I can get .002" or so on mine, and like Edfurg saud .002"-.003" seems typical and realistic.
I looked at mine to do a ballscrew conversion on, but it looked easier to me just to use the Taig to simply build another machine from scratch than to modify the stock Taig. Now I have the Taig for most use and a homebrew with ballscrews that I used the Taig to build. Ironically it cost about the same as modifying the Taig would have, as the major cost is in screws and a/c bearings. Easier too, I think.

I also scored a seriously beefy used Parker Daedal unit out of a laser optics facility that holds 1.3 micron, or .000051", but that is just getting stupid. It only has a 6" x 6" working envelope, But ground ballscrews and six(!) encoders. Its for sale cheap if you really feel the need something that blatantly insane, or just shop around for surplus if you are in a tech-rich area for something similar.

edferg
04-30-2007, 10:47 AM
Stepper - Have you posted a description or photos of your mill?

Also, send me a PM with details on your Parker Daedal unit. I have an application for a small working envelope mill for engraving.

I agree, It would be just as cheap to build a mill using ballscrews. I wish Taig offered a ballscrew version.

For a turn-key system, the Syil Products X2 and X3 are the lowest cost ballscrew mills I'm aware of: http://www.syilamerica.com/products.asp

Ed

GammaWill
05-04-2007, 03:04 PM
I have a brand-new Taig 2018CR-ER and after doing the disassambly-and-nut-adjust featured on Nick Carters Taig pages, I got my backlash to .002".

I typically mill symmetrical 1" mold cavities 1/4" deep in aluminum using a 1/32" ball cutter, and the backlash is not noticeable on my resulting parts.

Just the same, I tried using the backlash compensation available in Mach3 which dropped the backlash to zero, but it added a crazy ramped decelerator when the axis changed direction, which tended to stall my steppers when used with my gcode and the acceleration I had set on my axes. I couldn't get rid of the funky behavior, so I abandoned the backlash compensation altogether.

It is kind of funny - my guage measures thous on a big dial, and a deflection of .002 looked HUGE on it. At first, I thought "Oh Noes!", but then I stopped and asked myself "Will, is it *really* that bad?". It wasn't. :)

CuttingTools
05-07-2007, 07:57 AM
I worked with the Taig over the weekend and I was able to get the backlash to .002 by adjusting the lead screw nut. My screw does have some wear in the center as it is now tight at both ends of the travel. All the parts I machine are small so this is not too much of a problem. I am going to order new screws and nuts for both the X and Y axis< when I install these I am going to add a bijur automatic oil pump so I know that they will always be well oiled.

Scott

edferg
05-07-2007, 11:37 AM
Give us an update when you install the new parts. I ordered a new nut for my X axis but have not installed it. The brass leadscrew nut has a boss that appears to be press fitted into the mill. Not sure how to remove it and align the new one.

Ed

cartertool
05-07-2007, 05:04 PM
You can press it out, or carefully use a soft punch and punch it out.


The brass leadscrew nut has a boss that appears to be press fitted into the mill. Not sure how to remove it and align the new one.

Ed

fretsman
04-28-2011, 06:33 PM
you can converted Taig mills to ballscrews without any problems
go to cnc kit router mini mill BF20 taig ballscrew - Build Your Own (http://www.conversioncnckit.com/)

Not a whole lot of info on that website at all.

Did you use this kit?

Do you have any pictures of the setup?

I saw your thread on the 5 axis Taig and was hoping you'd answer the questions others had for you there.

http://www.cnczone.com/forums/taig_mills_lathes/120223-my_new_taig_5_axis.html

awerby
04-29-2011, 03:56 PM
In another thread, you wrote:

"yes but if i change do The distance of 150 mm machine is moved 149.35 it is sam problem bath i dont no wath"

It was a bit difficult to understand what you meant, but it sounds like a problem, and not inconsistent with a backlash error. Was this the same machine you put the ballscrews in?

Andrew Werby
ComputerSculpture.com &mdash; Home Page for Discount Hardware & Software (http://www.computersculpture.com)

Rift
05-01-2011, 04:14 AM
that problem is nat with taig machine that problem is with bf20 on this machine i have NSK BALLSCREW

Any chance you could provide some more pictures of your ballscrew setup?

I'm a bit leery of that site you linked there isn't much info and seems like a lot of the links just don't do anything.

awetmore
05-03-2011, 11:28 AM
That same guy has been spamming the taigtools mailling list. Since he doesn't provide very detailed information (even a photo or a set of installation instructions) I can't expect most people to order from him.

I was fighting some bad X backlash on my Taig mill recently and it turned out to be the nylock nut that holds the coupler in place. I reinstalled the coupler and my backlash is around 0.0015" right now. I'm good with that.

I also made new coupler tubes (the little plastic tubes) and found an easy source for them. Many Bic-style pens have ink tubes that are the same diameter (just under 1/8", I think it was 0.120"). One pen tube is enough for one coupler.

Punisher_67
05-06-2011, 11:19 PM
This certainly would be a worth while upgrade but more info would be an asset . I have new leadscrews and nuts on hand for my X , Y and Z axis but may go this direction instead

awerby
05-07-2011, 04:30 PM
Please let us know how it works, okay? As was pointed out, there's not much information on that site on the installation details. I'm particularly curious about how the ballnuts interface with the existing Taig setup, which doesn't have room for the typical ballnut flange.

Andrew Werby
ComputerSculpture.com &mdash; Home Page for Discount Hardware & Software (http://www.computersculpture.com)

Punisher_67
05-07-2011, 07:33 PM
I agree either $hit or get off the pot , This would be an awesome upgrade but the lack of info is a little disapointing .

Forums like this are a great help if info is shared

fretsman
05-07-2011, 09:45 PM
i will add video haw is working the ball screw

I really don't think that's going to be enough info to promote your ballscrew conversion. Especially when we're talking the type of cash you're asking for.

Jeff-Birt
05-08-2011, 12:34 AM
Personally I fail to see the cost/benefit analysis of ball screws on a machine the size of a Taig.

The advantages of high quality ball screws are longevity, efficiency and low backlash. They provide an efficient and accurate means of of motion that does not need the maintenance of other systems.

Cheap ballscrews are no better backlash wise than good ACME screws. Also don't forget that lead screws are also rated by their pitch deviation per unit length. Who cares if you only have 0.0005" of backlash if the pitch is off 0.001" over 4"?

Now, with care a Taig's backlash can be easily adjusted to less than 0.001". If you keep the screws lubricated and tweak it every six months it will stay that way. For most folks they will have a lot more variation in the dimensions of what they make from tool wear, the way the GCode is written etc.

If your building an industrial machine that will run 24/7 then it is a different story.

Punisher_67
05-09-2011, 01:19 PM
I see the benefit even on a Taig mill but I certainly cannot justify the complete package cost of $1100.00 for the complete kit . Like come on thats flipping hi way robbery considering the whole machine less the cnc equipment costs only $925.00 .

Post a picture or something Komar of the complete kit and not some lame video .

John Bear Ross
11-12-2011, 08:14 PM
Here's a 5-Axis Taig from Canuckistan, eh.

Taig mill 5 axis with ball screw - Taig Ballscrew BF20 Mill milling routing machine machines (http://www.cncconversionkit.com/product.php?id_product=30)

Pricey ($5,775 USD). But, it has ballscrews, and choice of trunnion table or rotary on the A and Z.

270 oz/in steppers.

Post processor looks to be an extra $1000 (!).

I wish I had the cash, or Taig offered it from the factory like this.

Best,
JBR

Punisher_67
11-12-2011, 11:12 PM
They are way out to lunch on price , you can piece that together for less than that .

John Bear Ross
11-12-2011, 11:40 PM
They are way out to lunch on price , you can piece that together for less than that .

True, but they're also probably catering to jewelers who want turnkey solutions, and are used to paying $25K for a Neo5 or MDA Precision 5 axis mill.

Best,
JBR

acidcustom
11-16-2011, 04:34 AM
has anyone ever tried these
dumpsterCNC - anti-backlash solutions for home and industrial linear motion (http://dumpstercnc.com/)

Bob La Londe
02-27-2012, 10:41 AM
has anyone ever tried these
dumpsterCNC - anti-backlash solutions for home and industrial linear motion (http://dumpstercnc.com/)

Specifically: I have a set of his 1/4" acme screws on my MaxNC 5. They are OK, but 5 lbs spring force is not enough. I can easily overpower the springs. Its ok if you are doing engraving (which isn't usually critical anyway) or if you take light cuts and go slow. I don't know if its better with his larger nuts.

Just about my machine in general:

I have well over ten thousand hours on my Taig. Probably closer to twenty thousand. I could adjust it down to as close a .001 -.0015 when the screws where fresh, but I also had to tighten the gibs pretty tight. Even fresh it would stall at that range if I ran faster than about 10 IPM. Just too tight. At about .003 it was ok, but now that there are tons of hours on the machine anything tighter than about .005 will cause it to bind and stall at the outer range of its travel. I can grab the table an feel the movemement at .005. On the other hand at .005 she will run 45 IPM all day long. The other problem is that it seems to wear pretty fast. I keep the gibbs and screws lubricated. A one shot or even an automatic oiler would be better, but I haven't done it. I just manually grease everything everyday. Anyway, I guess my point is if you really use this machine you will wear it out. I know its a light duty hobby level desktp machine, but its got some potential. If it had a slightly better Z-column ways design, and double nut ball screws it would be unbeatable for its size. I am thinking about buying one of the sets of ball screws from the guy making the conversion up in Canada. His design looks like single nut, but he is claiming sub .003 consistently. My only conern is I have extended my Y travel and I am going to hate to lose that with the conversion if his screw isn't long enough. If I do the conversion the machine WILL be getting some kind of oiling system as well.

Either that or buy a Syil. LOL.

The Taig is a good deal for the money, but by the time you upgrade it to be really good you could have bought a Syil X4 or an X4 Speedmaster. Still we all have to start somewhere. If it hadn't been for the Taig price I never would have gotten into CNC machining. I was also thinking about selling it, but I learned so much on the machine that I kinda want to keep it anyway even if I retire it completely.


Now, with care a Taig's backlash can be easily adjusted to less than 0.001". If you keep the screws lubricated and tweak it every six months it will stay that way. For most folks they will have a lot more variation in the dimensions of what they make from tool wear, the way the GCode is written etc.

That would be awesome, but I have found that when running at good speeds I need to tweak it every 6-8 hours to even keep it .003 or better. When running a 30 hour job (I know. I know. It was never meant to do that.) it will change dramatically during the course of the job. Now that my machine is substantially worn it can't be run full range at .003 or better.

awetmore
02-27-2012, 10:48 AM
At 20,000 hours it seems reasonable to spend $150ish on new stock leadscrews and nuts and then get your backlash back down to reasonable numbers. I think of the leadscrews and nuts (especially the nuts) as moderately consumable items, and like that Taig makes replacements so readily available.

bjm323
02-29-2012, 09:47 PM
Looks to me like the guy is claiming .0003" not .003". That is a lot of coin for that conversion if it's no better than .003" backlash.

Bob La Londe
02-29-2012, 10:12 PM
Looks to me like the guy is claiming .0003" not .003". That is a lot of coin for that conversion if it's no better than .003" backlash.

My mistake. I meant sub .0003. It should be able to rapid faster as well with those screws if running steppers.

Bob La Londe
03-01-2012, 12:16 PM
At 20,000 hours it seems reasonable to spend $150ish on new stock leadscrews and nuts and then get your backlash back down to reasonable numbers. I think of the leadscrews and nuts (especially the nuts) as moderately consumable items, and like that Taig makes replacements so readily available.

I looked and emailed Taig (usually quite responsive) and haven't found that.

Never mind. I see Super-Tech has them listed.

Bob La Londe
03-02-2012, 01:24 PM
Not so easy as I thought. I have been trying to order screws and nuts. Super-Tech shows a screw not listed for sale. Taig would prefer I order by part number, gave me a list of part numbers, but then said, "Make sure these are the parts you want." I have looked over the Taig website, and have not been able to find a parts diagram, or a parts list which I can use to, "Make sure these are the parts you want."

It may seem a little OCD on my part (and it is), but I hate to order parts and not KNOW they will be the right parts. When the manufacturer tells me that I need to make sure they are the right parts it makes me a little nervous.

fretsman
03-02-2012, 01:35 PM
Not so easy as I thought. I have been trying to order screws and nuts. Super-Tech shows a screw not listed for sale. Taig would prefer I order by part number, gave me a list of part numbers, but then said, "Make sure these are the parts you want." I have looked over the Taig website, and have not been able to find a parts diagram, or a parts list which I can use to, "Make sure these are the parts you want."

It may seem a little OCD on my part (and it is), but I hate to order parts and not KNOW they will be the right parts. When the manufacturer tells me that I need to make sure they are the right parts it makes me a little nervous.

Does this help?

http://www.cartertools.com/expmill.gif

Dave

Bob La Londe
03-02-2012, 02:32 PM
Does this help?

http://www.cartertools.com/expmill.gif

Dave

Thanks.

cameraguy
03-02-2012, 04:20 PM
the 25, 25a and 26a are the standard set for a 2019.

however, when you order new nuts and screws, you can simply order two Z axis screws and one X. (two (2) 25a's and one (1) 26a). also order part #1251, the lathe headstock spacer/riser block.

the reasoning for this is that the Z axis screw is identical to the Y save for it is about an inch or so longer. add a pair of one inch standoffs (and longer allen screws) to attach the Y bearing plate to the machine, and now you have an extra inch of Y travel. to use this the headstock needs cantilevered out an inch, which is where the spacer comes in. install it and you will gain an inch of throat as well.

any extra throat affects rigidity obviously, so if you need to really hog anything out you can return the machine to normal by temporarily removing the spacer block if you get any vibration or chatter. for most every normal use though, it works wonderfully and is plenty stiff, and that extra inch really helps a lot. even if its just keeping the rear rubber mat free from pinching against the column and losing steps, its a livesaver.

Bob La Londe
03-02-2012, 09:07 PM
Well, I got the screws and nuts ordered from Super-Tech. Didn't catch that bit about the Z & Y until after I placed the order. The screws are cheap enough though if I want to just order another screw.

I might mention that I already put spacers on my Y axis with the "stock" screw that came with the 2019, and I am using a home made spindle mount for a Porter Cable router that puts the spindle center further out from the column. I can work on pieces 12 x 6+, and sometimes do.

I also was trying to get some more info from the guy who sells the ballscrew kit. He doesn't answer questions very well. He responds, but its so short and meaningless as be totally useless. I would guess that's probably the main reason he hasn't sold more of them if he responds to everybody that way.

fretsman
03-04-2012, 08:45 AM
Bob, were the parts you bought cheaper from Super Tech even with the 10% discount you get from Nick Carter (cartertools.com)?

Thanks,
Dave

Bob La Londe
03-04-2012, 11:30 AM
Super-Tech was the same price as direct from Taig. Didn't even know Nick Carter offered a discount. Oh, well. Its not like they were expensive parts to begin with.