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View Full Version : Taig MicroMill DSLS 3000 versus Seig KX1/KX3 ??



squale
10-03-2008, 08:20 PM
I'm looking to get a small cnc mill to learn cnc machining on so when I step up to the larger cnc machines I have a good idea of how to program, etc.

what do you feel about the Taig versus the Seig KX1 ? They are both about 3K.

and how about the KX3 ?? is that a big step up from the Taig and KX1 ?

thanks

Stepper Monkey
10-03-2008, 09:13 PM
Taig is a big step up from the X1, X3 is a big step up from the Taig.

Stick with X3 or Taig depending on your needs, the X1 is generally considered nigh unusable.

On another note, the particular closed-loop system on the Taig you mention is not generally considered to be of as great of practical value or utility as it first appears, nor is any closed-loop stepper system for that matter. Probably not extra money well spent over a good open-loop system.

I would suggest either (1) if you are going to spend that amount of money for the DSLS go ahead and just get the X3 if it is what you need, or (2) save a bundle over the DSLS and just get a basic Taig with a far superior Gecko G540 driver for far less money.

Can't say which option is best for you as we don't know exactly what you are looking to be making.

squale
10-03-2008, 10:42 PM
well can you explain what the open loop versus closed loop system is all about and why one is better than the other?

I am mainly looking to learn cnc machining and be able to make some parts out of delrin, 316l stainless and some aluminum. Most of the stuff will be stainless 303, 304 or 316. Other stuff will be plastics such as UMHD, PET, and Delrin.

Here are some sample parts I would like to make: http://www.thewholepkg.com/index.aspx?ContentPage=ChangeParts

all of these parts are within 6" long by 4" wide or less.

TOTALLYRC
10-03-2008, 11:38 PM
well can you explain what the open loop versus closed loop system is all about and why one is better than the other?

I am mainly looking to learn cnc machining and be able to make some parts out of delrin, 316l stainless and some aluminum. Most of the stuff will be stainless 303, 304 or 316. Other stuff will be plastics such as UMHD, PET, and Delrin.

Here are some sample parts I would like to make: http://www.thewholepkg.com/index.aspx?ContentPage=ChangeParts

all of these parts are within 6" long by 4" wide or less.

Hi squale.
As a taig owner I wouldn't be thrilled if I had to do a lot of stainless parts. :(The rigidity isn't there. You can do work in stainless but you are very limitied with depth of cut.
The Taig will do the delrin and aluminum with a minimum of fuss.

Based on what stepper monkey said, I would go with the x3 based machine.

There is a reason why machine shops use large cast iron machines and it because of the mass and the vibration dampening qualities of cast iron. Something to do with the carbon atoms inside the cast iron matrix
A machine made out of steel is going to have more vibration problems. Take a piece of steel and hold it lightly in your fingers and tap it with a hammer and it will ring. The ringing is vibrations freely traveling thru the steel. Cast iron will dampen most of the vibrations.

Open loop means that we tell the steppers where to go and we take it on faith that they get there. If it doesn't get there it is called losing steps.

Closed loop means we provide some sort of feed back to the control "closing the loop".
In a servo based system it has to have encoders to close the loop to at least the drive if not the computer. The DSLS system I believe has encoders mounted on steppers to close the loop.

I would say however that far more hobbiest systems and a fair number of real cnc machines run open loop than closed loop. With the advent of good open loop drivers such as the g540 and others that have mid band compensation open loop rocks.

Especially from a cost benefit ratio and ease of setup.

Once set up properly an open loop system will not loose steps unless there is a problem. Properly setup means that you are running with a safety margin on the stepper stalling speeds and you keep the ways properly lubed and so forth.

Mike

Stepper Monkey
10-04-2008, 01:39 AM
There is a lot of data on both types of systems, it would take a small book to go into all of the details though.

A closed loop system on servo motors is necessary, as the motors don't automatically know where they are - they act rather like a normal electrical motor and so they require an encoder system to tell them how far they have moved, and to correct for any errors. A stepper motor moves a known position each step, and so under normal circumstances encoders are entirely redundant. In a properly set up stepper system steps don't just get "lost" unless something is dramatically wrong. An encoder system would be useful here if it could correct any errors on the fly were something to go wrong, but the DSLS is not that advanced. It simply stops the machine if it registers an error. That's the limit of what it can do.
Now, if something does go wrong - like a crash or stall or running into the machines hard limits of travel - the system does register the lost steps and simply stops the machine, but it can't really help you recover from it. Even if it could, you usually can't use it's help anyway as the code was likely bad or your workpiece has been ruined or displaced, or the fixture needed repositioning, so you can almost never just pick up where you left off anyway. This type of simple system does have some use sometimes, its just extremely limited in scope and only ever activates outside of normal operating conditions. Under all normal conditions it is simply inactive and runs like an open-loop system, and under abnormal conditions is of limited help at best, if you are lucky - at most it will save you five minutes or less even if it is.

Obviously, having it is better than not having it if it was free, since it does has some use, but it is of so little practical use it just can't really justify the extra cost. That is why so few machines use it, even in far more expensive units where cost is not an object.

In my opinion it is mainly a marketing tool used to comfort people scared witless by servo salesmen FUD on the "horrors" of steppers, but who can't afford to spring for a full servo system. It is a poor middle ground that costs nearly as much as servos while delivering no better real-world performance than a base stepper system. Just go with one or the other, both well exceed our needs in any case.

jalessi
10-04-2008, 02:32 AM
Squale,


Most of the parts on your link would be made on a CNC lathe not a mill.


I personally don't think either the Taig or the X3 is the right choice for any of the stainless parts period.

You will be making a big mistake.

Jeff...

philbur
10-04-2008, 05:17 AM
And if he only needs a few of each then a manual lathe would also be a far better alternative than a CNCed mill. He could be up and running for $500 rather than sitting with $5000 worth of equipment that doesn't do what he needs.

He should be looking here:

http://www.grizzly.com/products/mach-specs.aspx?key=460

Phil:)


Squale,


Most of the parts on your link would be made on a CNC lathe not a mill.


I personally don't think either the Taig or the X3 is the right choice for any of the stainless parts period.

You will be making a big mistake.

Jeff...

Stepper Monkey
10-04-2008, 06:12 AM
I just looked at the link too, that is definitely lathe territory, and likely manual lathe unless you are going to do a lot of the same identical part.

A good manual lathe is much cheaper than a CNC mill, too, so you can afford to get a fairly beefy one.

squale
10-04-2008, 11:19 AM
I was thinking along the same lines now with a manual lathe. What do you guys think about the Micro-Mark 7 x 14 lathe? http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=82710

or even the Sieg C4 lathe sold here in the usa by Travers: https://www.travers.com/c4/

could either of those lathes turn the work shown on that link? Those parts again are no more than 8" long by 4" OD

Mostly either 303, 304 or 316 ss or plastic such as UHMW, PET, Delrin, PVC, etc.

hoss2006
10-04-2008, 01:59 PM
Forget the 7X? lathes if you want to cut stainless, they can't handle it.
A little better would be the 9x? lathes like the Travers but I don't see why they are
charging double what grizzly does and they don't even give you a 4 jaw chuck.
Maybe it's the digital tach that costs so much.:)
The power cross slide is a nice feature but not needed if CNCing is in the future.
G4000 9" x 19" Bench Lathe (http://www.grizzly.com/products/9-x-19-Bench-Lathe/G4000)
The best option would be a 10x22 from Grizzly (http://www.grizzly.com/products/10-x-22-Bench-Top-Metal-Lathe/G0602), it will handle the work no problem.
It may be backordered a couple months when you order but it is well worth the wait.
Mine can cut case hardened ballscrew like butter whereas my old 7x10 was nearly useless for anything harder than aluminum.

jalessi
10-04-2008, 02:08 PM
Hi again,

Hoss is giving you very good advise.


I don't want to step on toes here however the fact is you keep saying STAINLESS STEEL.


STAINLESS STEEL work hardens very easy and taking a light cut will do that in quick order.

Get the biggest lathe that can take a very aggresive cut, otherwise you will be spinning your wheels.

Talk to some of the guys that work with STAINLESS STEEL on a daily basis before you waste alot of money.

Jeff...

squale
10-30-2008, 12:10 PM
can anybody comment on why the Taig is better than the KX1 ?

sansbury
11-01-2008, 06:06 PM
"can anybody comment on why the Taig is better than the KX1 ?"

Probably not, the KX1 is still pretty new with very few out there. Don't even know who sells it in the US. A lot of commentary on it is by people talking about the X1, which is substantially different. The KX1 has a totally different vertical column and spindle assembly, which are the weakest parts of the X1 by far.

Taig OTOH is very well-known. It is small though.

squale
11-01-2008, 06:28 PM
well I think the KX1 and the Taig are about the same size correct?