Official Luthiers Forum!

Andy, the 8080 profiles sure do look massive and with the heavy endplates is looks like the frame would be self-supporting.
I don't see any leveling screws so I'm assuming you can set it down on an uneven surface and it doesn't flex to conform?
That would seem to be the advantage of the extrusions, strong yet light.

P.S. Would that be your mentor or your apprentice on the shelf behind the machine?

There are holes drilled and tapped for leveling feet or bolting to a bench in the end plates, I just haven't stuck anything in there yet as I'm planning on building a bench from unistrut. I'll use the holes to bolt it to the bench and the bench will have leveling feet.

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Ahh.. You're on CNCzone too, now I get it. Your neck work looks great!



Just for discussions sake, I've actually changed my mind a bit from when I started this process and was looking for a full blast turn key system: One of the things that has become kind of apparent is that because the Xzero is more like a semi finished kit rather than turn key, I now know a heck of a lot more about the machine and how this stuff works than I would have had I gone with a turn key system like a Romaxx or Shark etc.

I could also see how for some folks, especially those who aren't familiar with electronics and electronic controls could get pretty frustrated but, if you can hack your way through it, you'll end up with an accelerated education in CNC.

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For me, I think the frustration would be more of knowing what to expect from the machine and learning some of the specific issues between CAD/CAM/Machine. I've made my living in the computer industry since the mainframe days, and have a lot of automation experience along the way, but old age and laziness has led me to turn-key solutions. Of course, I'm never willing to let a turn-key solution stay as-is once I've learned what I want to from it. Still too much tinkerer in me I guess, and I'm pretty set in my ways. I was working with servo controlled systems that are a lot like today's CNC machines 30 years ago. All that technology has changed very little since then (except pricing!), but design software has changed a lot. That's where I really had the learning curve to go through.

At any rate, I've learned a lot more since I've been re-working the Raptor I got and it's been a blast. I can't wait to see some bandura parts coming off of your machine, Andy! Actually following your posts on the various forums is what led me to getting the Raptor that I have. No regrets either--I'm able to do much more with it than I had expected. It's a very stable and well thought out machine, yours with the upgraded parts should be even better.

Dave

The unistrut table sounds like a good idea as it would probably flex rather than the router frame.
It's true that we're only machining wood in most cases.
Being from a machine tool building background, I tend to "worry" about axis alignments etc where .001"/ft. non-accumulative was the norm.
With that said, however, instrument-making does require more precision than sign making, for example.
The large surface area on the ends of the 8080 extrusions, for example, call for precision machining for squareness.
Just some thoughts.
Nelson

I'm not much of a machinist but I know what you mean. I figured that I'd take some time to set up the machine now and then forget about it. As I mentioned, I spent about an hour adjusting the rails so that they're parallel to the extrusions and I managed to get it to within 4 thou over the length of the table. I was using a dial indicator fixed to the rail measuring against the extrusion so I realize that's not the ultimate in accuracy but should be good enough for what I'll be doing.

The ends of the 8080 were faced with an end mill (George actually has some videos of his machines being manufactured) and once I got everything aligned and tightened down, everything is as square as I can measure with the tools that I have.

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Thanks for the feedback, Andy.
I would certainly consider the XZero for my next CNC.
I like the open construction as it would allow a 4th axis trunnion fixture to fit in.

The problem might be because it is rack & pinion, R/P and not meant for accuracy ,with more advanced ballscrews is the way to go, R/P was before for longer machines,with ballscrew now affordable for the larger machines,ballscrew would be the way to go other than rollor pinion or helical R/P ,but plain R/P they are not precision made,but are only 1/3 the price of a ballscrew,so that is why people use them on machines

Hey Andy, thanks very much for posting your experiences. I read every word with interest. I am in the same position as you were, trying to make a decision on a CNC. Have been thinking about it for a long time, but got serious in the last couple of months. Did a lot of research, looked closely at the machines you considered and also the Shopbot desktop, but as soon as I get the approval from SHMBE (very tricky) will be ordering a Xzero. Knew nothing about George and his machines until I saw your posts. Impressive looking machines, solidly built and affordable. Not turn key, but I can handle that.

Since my last post I have ordered a larger Raptor from George--the width on mine is fine, but the length is just a tad short of what I need for a few projects I have in mind. I ordered a 24X48 to replace my 24X36. But its a positive vote that I ordered another XZero. It's been on order for awhile, but hopefully mine is going to be shipped here in the next day or two.

From my experience so far, George's machines are very nice (especially for the price), and he genuinely is trying to improve them even when they were very good to begin with. Patience seems to be the key right now. I think George probably bit off more than he knew he had when he started selling the machines, and has been struggling to get his company beefed up to the same level his machines have been. I did the same thing with my banjo business, so I empathize completely. The orders I got completely caught me off guard, and I'm afraid I pissed a lot of people off in the process of getting things together. Live and learn. The XZero is helping me get MY business issues worked out.

But George is adding some additional people (I think he's been trying to be manufacturer, marketer, packer, shipper, ombudsman all at the same time) and a new larger facility specifically set up for packing and shipping machines. I've emailed with him many times and have talked to him on the phone and have found him to be a very nice guy. But as I say, I think his company is at one of those critical times right now where demand has outweighed supply and it's just taking him a little bit of time to catch up with it all. My advise is that the machine is well worth the patience, but it still requires some patience. George really is trying to build the machine that many of us have really been looking for--solid, well made, and priced within the reach of a modest instrument shop. I wish him the best in this endeavor. The Raptor I've been using has completely revolutionized the way I'm building instruments. I'll be back with an update after the new machine arrives.

Dave

I'll second what Dave has to say which brings another piece of advice to anyone who's following: Buy the biggest machine you can afford - in fact stretch yourself a bit.

I bought the 24x36 but I think if I had it to do over, I'd go for 36x48. It's not that I need this size right away but I'm just thinking of possibilities that will be more difficult due to the size I decided on (e.g. 24" radius work boards, bass necks etc.). If I ever do upgrade, I'll almost certainly buy from George again.

I've got my machine as set up as it's going to be for the next 3 to 6 months and I'll try and get some video maybe tomorrow.

The attached picture is from some fooling around I did yesterday. I just drew up a funky spline pocket and inlay to see how tight the machine is. I made a mistake in the G-code and when I tried to cut the male inlay portion I somehow accidentally set the depth of cut to 1" and the first plunge cut was at 1" depth at 100ipm. The only reason I noticed was because the work piece was moving! No broken bit, no stalling, no nothing. You can see the 1" depth cut right next to the inlay - or at least the portion of it made before I hit stop! I think with a weaker machine or a weaker spindle (I have a 2kW) I would have at minimum broken the bit.

This may be no big deal for those of you with high dollar machines but I'm pretty impressed. The pocket is .003" smaller than the inlay and it's shrunk a bit since yesterday. The grain is at 90o because I generated the G-code such that the inlay was machined 90o to the pocket to maximize any errors between the axis. Not bad if you aksed me!

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And I agree with Andy--buy the biggest machine you can afford....and fit into your shop. That's been my problem (both factors actually). I'd have probably ordered a bigger machine yet, but I have a really small shop and even a 24X48 is really pushing it for the space I have. a 36X48 wouldn't fit unless I got rid of my table saw, which isn't going to happen. The 24X36 will do a whole lot--everything that I'm wanting to do anytime soon. But in addition to banjos, I'm a steel guitar and uke guy. Ukes are obviously no problem, but steels are. With a 48" long machine, I can do electric lap steels as well as banjo cases that I can't do with the shorter machine unless I do it in indexed steps.

Dave

OK, thanks for that advice. I just emailed George upping the size to the biggest I can fit into my shop (30 x 48). That size should be future proof (I hope).

Nice Machine Andy. I'm looking at getting one within the next year or two. Where did you find this one?

Well, no thanks to the spammer that brought this thread back up, but I'm still using my second XZero CNC. It was something of a struggle to get all of the parts from the vendor, and it was definitely more of a pile of parts than it was a kit. But the parts were well made and the machine is still working great today. I've done several upgrades. Thanks to Andy for bringing it to my attention to begin with!

Dave

What a blast from the past! I'm still running two Xzeros almost every day and adding a third machine in the next few weeks (not an Xzero but probably at least as good - Avid CNC desktop Pro - will be cutting tenons and other odd jobs). My first Xzero machine is still in use - ran over 8 hours yesterday and will soon be getting an upgrade to step/servos and an ATC spindle....my how time flies!

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Have you got an ATC picked out, Andy?

If so, which manufacturer are you going with?

I'll be interested to hear about your step/servo upgrade too. I've beefed up my steppers/drivers quite a bit over the years, and really after switching to UCCNC, I have been extremely pleased with the Raptor's performance. It wasn't shabby before, but it's definitely better now.

Dave

I decided to go with the CNCDepot spindle here: https://www.cncdepot.net/product-page/f ... s-spindles

There's cheaper out there but this is U.S. made and I've gotten some very good feedback about them. Checked runout when I got the one and it's almost nothing. <0.0002" for sure. I have one on hand and two more on the way. For anyone thinking about buying any sort of spindle right now - buy as soon as you can, spindles are in rather short supply in the U.S. right now.

Haven't had a chance to play with it yet as my new machine isn't together yet and I'm still waiting for the control box - for once I decided to not go DIY on the control box. Arturo from CNC4PC is building two of them for me, one for the brand new machine and one for the oldest Raptor. The control on it now is 48v G540 DIY based. Top speed of about 380ipm and accels around 50"/S^2 - ish

My newer machine (larger Raptor, 30x48") runs 65v with Applied Motion Technologies step/servos - TSM23P in a 3AG or 4AG size depending on the axis. Runs a UC100 with a C11 breakout board (also from CNC4PC) in a homemade control box. Top speed is 580ipm but that's limited by the UC100's slow kernel speed. I think it could go a bit faster but with just one ballscrew I think I'll be hitting the RPM limits of the screw soon. Worth mentioning that both my old and new raptor have 10mm pitch screws.

Accels are between 90 and 110"/S^2 but that might be a bit deceptive, I'm not sure the servos are quite keeping up with that. Probably 80 to 90 (depending on the Axis) would be right. It used to take me about 45min to cut the back side of a neck, with a faster top speed (I cut at max velocity) and almost 100% increase in accels, it now takes about 30. I cut a part that normally took I think around 13 min to machine and the accels alone dropped that time to 9min - that's running the identical program, same feedrates, just faster rapids and accels .

I cut necks at 580ipm all day with that thing. I'm hoping to get a even a little more speed out of that machine once I upgrade to a UC300 or 400 which I need to do to get enough I/O to run the ATC.

The thing I love most about the servos is that when something goes wrong, it catches it instantly. The other day, I took too aggressive a cut in an unfamiliar wood (and I think I need to adjust my VFD settings) and stalled the spindle before I could hit e-stop...good news was that the servos hit the e-stop for me pretty much instantly. Work piece - a custom electric neck in roasted maple wasn't damaged at all. I slowed down my feed, re-wound a bit and kept going and, wait for it....didn't even have to re-home the machine .

A few weeks earlier, I was running some standard acoustic necks on the G540 based raptor, open loop stepper machine and something went wrong while I wasn't at the machine. Heard some nasty noises and found out that somehow the neck had come off the vacuum fixture (located with 1/4" dowel pins no less) and been destroyed in the process. I also found out over the next few weeks that I probably wrecked that spindle in the process - was breaking small end mills like never before - found about .0025" runout in the spindle. Ok for cabinet work or something like that but a no-go for micro end mills. Thank you open loop control

[Edited to make it clear that the non-servo machine caused all the ruckus]

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Very cool--thanks for the info. I'm using a UC100, and your speeds/accels look pretty close to mine. I'm running 48 volt C11/Gecko 203 Vampire drives and a Colombo spindle. I'm not running closed loop controls--just big steppers and re-home between tools.

In my earlier professional days, I did a lot of work with industrial servo systems where absolute precision was key--with wooodworking, it's not so much so. But I'm also not in a hurry, doing work only for myself, so pushing the machine closer to the limits isn't a concern of mine.

Dave

I edited my last post to make it more clear that it was the open loop stepper machine that caused all the troubles.

And Dave, I got the step servos not so much for better accuracy, the steppers are good enough for that, it was for the extra power and so that it would e-stop on a stall instead of wrecking things. If I wasn't running these things every day, I'd be happy with the steppers.

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