[ChrisAttebery]

I've seen a couple post stating that the G0704 is preferred over the Sieg X3 based machines. Can someone help me understand why that is? I'm coming from an Enco RF30 clone. On paper it would seem that the X3 machines would be better because they weigh over 100lbs more than the 0704.

I want to build a mid sized machine that I can get a comercially available CNC mount/ballscrew kit for. These two machines fit that bill.

I'd just keep my machine, but I don't have the time or engery to make my own conversion. Another option I have looked into is buying a Dyna 2400 CNC mill. I found one that I could pick up for around $2500, but it is a pretty small and slow machine compared to a conversion.

Thanks,


Chris

[photomankc]

Mostly relates to the Z axis. Lots of head droop issues and chatter in heavy cuts. Bigger table and tapered gibs. Basically nothing the X3 really does any better and several areas it seems to perform worse in. I almost went that way but ended up very happy with my PM-25 machine. I don't miss the 100lbs in any appreciable way.

[ChrisAttebery]

That's what I needed to know. Thanks!

[Connor]

In sort, G0704 more rigid despite being 100lbs lighter. Somewhere in Hoss's thread is has a compassion of all the different benchtop mills. G0704 came out on top in most of the cases when compared to the X3

[rwskinner]

The biggest issue are the Z axis gib strip in the SX3 / X3. They are machined at the wrong angle from the factory and the factory will not fix such an obvious mistake. A little time and it fixes most of the problem.

The G0704 has an Edge on the SX3 because you can control the motor much easier on the G0704 and X3 and can't on the SX3.

The Z is lifted more towards the center on the G0704 (I think) keeping the head from nodding as bad, the X3 and SX3 lift from behind the column and tends to cock the head unless the gibs are perfect.

Richard

[ChrisAttebery]

Thanks guys. I'm thinking through a couple different options and this really helps.


Chris

[H500]

Here's my observations, as a sx3 owner who is half considering trading it for a g0704 for better portability.

I'm not convinced that the g0704 column is a rigid as people say. It's closed at the bottom, but a slot runs up the center front for the lift mechanism. The sx3 column is open, but it's bigger. I can probably make it more rigid by adding a plate at the bottom.

The throat distance on the sx3 is about 2" deeper on the sx3. It's good if you need the clearance, but the cantilever also makes the machine less rigid in torsion.

The g0704 uses tapered gibs on all 3 axes. The sx3 only use them on the z axis. The x and y uses 4 screws. It's more difficult to adjust.

The sx3's z axis gib tends to be poorly machined. They have a slight concave that causes the head to nod when changing directions. It's about .0007 on my machine, no matter how tight I make the gib. I will need to fix it once I have the confidence.

The sx3 uses a relatively powerful brushless dc motor. There's no carbon brushes to wear out. But the electronics are more complex and the control is poorly thought out. The spindle speed is changed by pressing up/down buttons. Very inconvenient.

The sx3 spindle only goes up to 1800 rpm. There's no gears. It runs quietly, but the speed range is too limited.

[wizard]

I've seen a couple post stating that the G0704 is preferred over the Sieg X3 based machines. Can someone help me understand why that is? I'm coming from an Enco RF30 clone. On paper it would seem that the X3 machines would be better because they weigh over 100lbs more than the 0704.

There is this idea that weight and only weight is the only way to judge a machine on this forum. That concept is a huge mistake. Use the weight in the wrong way and you will not get a better machine.

I want to build a mid sized machine that I can get a comercially available CNC mount/ballscrew kit for. These two machines fit that bill.

Or you can buy a machine that comes from the factory as a CNC machine.

I'd just keep my machine, but I don't have the time or engery to make my own conversion. Another option I have looked into is buying a Dyna 2400 CNC mill. I found one that I could pick up for around $2500, but it is a pretty small and slow machine compared to a conversion.

Thanks,


Chris

Shop around and look at the various solutions available as CNC mills. In a nut shell machines from LMS, Tormak and other similar vendors trying to deliver low cost machines.

As for the 704 people see that as a better constructed machine. Sound mechanical design can do wonders within a given weight range. A purpose built CNC machine does allow for slightly better redistribution of the allocated weight. Now the focus on weight here isn't by accident, these small mills have limitations placed on their weight due to the market they sell into.

[Flexo!]

I havent read many reports quoting how bad the X3's column is, but this page:

My CNC Adventures about half way through "Crap thing about the X3 #2: The Column"

Quotes 0.5mm deflection with just 10kg force applied to the spindle nose.

There's a few differences in travel lengths etc between the X3 and G0704 style machines, but on my WMD25 the deflection "twist" was 0.3mm (measured at the spindle, approx 185mm from the column, 20kg force applied at the very front of the head).

If these numbers are to be trusted, Seig are doing something very wrong with the extra 100kg!

[Fastest1]

The price is a little high on the that Dyna 2400. That being said, it is ready to run. Though its work envelope is small and its gear reduction on the screws does slow it down, it is a very accurate and capable machine. I wish it had the travel of the G0704.

[H500]

On my X3, I'm getting slightly less than .002" (.051mm) deflection with a 10kg side force using the setup in the photo.

The bottom of the spindle is 5.0" (127mm) above the table. The center is 8" (203mm) from the column.

Would anyone be interested in measuring the g0704 for comparison?

[hoss2006]

Would anyone be interested in measuring the g0704 for comparison?

I could but it won't be a fair test. Mine is far from stock with the Z axis flipped, big rotary mounted on the head and a 2.5" column spacer.
I'll still do it once my fish scale arrives.
Mean times, would any X3/SX3 owners care to perform a practical test of the whole machine by duplicating any of the hogging videos I made?
These ones are when the mill was still pretty stock so an SX3 with it's more powerful motor should have no problem.
Projects
specs are given at the beginning of the videos.
Good luck, Hoss

[H500]

I could but it won't be a fair test. Mine is far from stock with the Z axis flipped, big rotary mounted on the head and a 2.5" column spacer.
I'll still do it once my fish scale arrives.

I would be very interested in what sort of deflections you get.

Mean times, would any X3/SX3 owners care to perform a practical test of the whole machine by duplicating any of the hogging videos I made?

That's quite impressive. I'm relatively new to machining. I don't think I have the confidence to push my machine that hard yet. If something went wrong, I wouldn't be able to tell until the damage has been done. When my roughing bit gets here, I'll see if I can make the machine work harder. I don't own any large size bits at the moment.

[Fastest1]

You might want to buy a few extra end mills!

I would be very interested in what sort of deflections you get.


That's quite impressive. I'm relatively new to machining. I don't think I have the confidence to push my machine that hard yet. If something went wrong, I wouldn't be able to tell until the damage has been done. When my roughing bit gets here, I'll see if I can make the machine work harder. I don't own any large size bits at the moment.

[H500]

You might want to buy a few extra end mills!

Each bit is a loyal servant, to be treated with respect and never abused.

[arizonavideo]

Does failure count as hogging?


[ame="http://www.youtube.com/watch?v=BsQO093GVeg"]Face mill fail! - YouTube[/ame]

[ChrisAttebery]

Well, after my third attempt at a Dyna 2400 purchase fell through I gave up and ordered a G0704 and CNC Fusion kit. I'm going to call Automation Technologies on Monday to discuss the electronics. I'd like to use a fairly new laptop I have, but it only has USB ports. I think a Smoothstepper is what I want but I want to make sure I'm not missing something.

[wizard]

If you go that route make sure it is the Ethernet based solution. You should also check out Dynomotion.

Well, after my third attempt at a Dyna 2400 purchase fell through I gave up and ordered a G0704 and CNC Fusion kit. I'm going to call Automation Technologies on Monday to discuss the electronics. I'd like to use a fairly new laptop I have, but it only has USB ports. I think a Smoothstepper is what I want but I want to make sure I'm not missing something.

[hoss2006]

On my X3, I'm getting slightly less than .002" (.051mm) deflection with a 10kg side force using the setup in the photo.

The bottom of the spindle is 5.0" (127mm) above the table. The center is 8" (203mm) from the column.

Would anyone be interested in measuring the g0704 for comparison?

Excuse the delay but below are my results.
Happy to say my head deflects less than .002 as well even with the mods to the head and column (slot is extended 3" lower).
My spindle is cantilevered farther away (10") and the head isn't in full contact with the Z slide (Z flip mod) as a stock G0704 and there's that big rotary 5th axis (I should have locked)
so I'm pleased.
Now if any X3 gentlemen would care to show how well their machine cuts as a whole?
Projects
Hoss

[ame=http://www.youtube.com/watch?v=MQ7Xuw7wmnc&feature=plcp]Fishscale Test - YouTube[/ame]

[Whizbang]

Excuse the delay but below are my results.
Happy to say my head deflects less than .002 as well even with the mods to the head and column (slot is extended 3" lower).
My spindle is cantilevered farther away (10") and the head isn't in full contact with the Z slide (Z flip mod) as a stock G0704 and there's that big rotary 5th axis (I should have locked)
so I'm pleased.
Now if any X3 gentlemen would care to show how well their machine cuts as a whole?
Projects
Hoss

Fishscale Test - YouTube

I wish I could get that kind of accuracy. I have something in the works to compete I'll post back in a few days