New Machine Build- Solsylva 25x25 Build

[NichB77]

Hi all,

I have been working with CNC for the past year or two, and really enjoy doing it. After being told I should make my own router, and seeing a Solsylva 13x13 working in person, I am seriously considering doing so. My two main set backs are money, as I plan on heading off to college next fall, and lack of knowledge. After reading Crane's 25x25 Solsylva Build w/ Pictures, which I think is amazing, I decided to start looking into prices on the specialty parts I am going to have to buy.

The parts that came to my head first were lead screws, bearings, steppers, and stepper drivers. From Crane's build I learned that 3/8 leadscrew is a little slow so I decided to go for 1/2"-10 5 start precision Acme steel lead screw, please tell me if I am crazy and I don't need something this high quality, which I found at $57.50 for 6 feet which, as far as I know, with 25" X + 25" Y + 8" Z should be enough.

As for the bearings I know from skating experience that Swiss makes the smoothest rolling, most durable bearings out there, and I figure these bearings are going to get saw dust in them so I decided on Bones Swiss Labyrinth bearings. Let me know if I'm crazy again. I found an 8 pack for $37, and I believe I will nedd 16 bearings, correct me if I'm wrong, so thats $74 which isn't all that bad for the quality.

While looking at stepper motors I thought about the mills I use at school, Technos that I love because they are quick and accurate and Denfords which take what feels like days to do the same thing. I decided I want to run at a speed similar to the Technos, which I believe use NEMA 23 stepper motors. After a little searching I found STP-MTR-23055, a bi-polar 166 oz-in NEMA 23 with double stack, for $30. This seemed like a good deal to me and I thought it I would be able to hit decent travel speeds (by that I mean IPM) with these steppers and the leadscrews I picked out.

Stepper driver is where I started to get lost due to lack of knowledge. I know I will need a chopper stepper that will allow me to make a 4 wire connection because my stepper motors are 4 wire. I think I want to have 1/16" microstepping capabilities. I do not know how many amps per phase I need, what type of current I want, or what type of power supply I want it to accept. For that matter I don't know what type of power supply I want either.

I know that I am going to need other specialty parts but I am not sure what those are or how many I am going to need of each part. If anybody could help me with my stepper driver and power supply questions, tell me what other specialty parts I am going to need, and/or tell me the parts I have chosen are too high quality for my machine I would be very greatful.

Thanks,
Nick

I plan on making this my build thread when I do start the actual build.

[ger21]

As for the bearings I know from skating experience that Swiss makes the smoothest rolling, most durable bearings out there, and I figure these bearings are going to get saw dust in them so I decided on Bones Swiss Labyrinth bearings. Let me know if I'm crazy again. I found an 8 pack for $37, and I believe I will nedd 16 bearings, correct me if I'm wrong, so thats $74 which isn't all that bad for the quality.

Buy them from VXB.com for about $1 each. You won't be able to tell the difference, and you'll save $50.


While looking at stepper motors I thought about the mills I use at school, Technos that

I love because they are quick and accurate and Denfords which take what feels like days to do the same thing. I decided I want to run at a speed similar to the Technos, which I believe use NEMA 23 stepper motors. After a little searching I found STP-MTR-23055, a bi-polar 166 oz-in NEMA 23 with double stack, for $30. This seemed like a good deal to me and I thought it I would be able to hit decent travel speeds (by that I mean IPM) with these steppers and the leadscrews I picked out.

166oz is a bit small with those leadscrews, imo.


It'll end up costing about $150 than something cheaper, but you should seriously consider the first or 3rd kit on this page.
Page Title

This gives you motors, drives, and power supply.

You'll get crazy fast speeds, with a ton of power to spare. And should you decide to upgrade to a bigger machine, it'll work fine with a bigger machine.
And it'll give you at least double the performance of anything cheaper.

[NichB77]

I'm suprised you won't be able to tell the difference between Swiss bearings and the cheap ones, especially when they are gonna be around all of that saw dust, but I will definitely go for the $1 ones. Any skateboard bearings will work I assume or do the plans from Solsylva come with a specific size bearing that you will need?

166oz is a bit small with those leadscrews, imo.

Are these leadscrews right for me in your opinon? I plan on cutting mostly hardwoods. Maybe a little corrian or plastic. I don't really have any reason to cut metals ever except maybe some aluminum if im feeling adventurous.

Those packages are awesome. I was looking a Gecko drives, but I thougt I might be able to find something a little cheaper. My budget is somewhere around $500 and, depending on what other specialty parts I'm going to need to order, those kits might be a little out of my price range. I will definitely look around and try to find either the pieces to the kit or the whole kit at a cheaper price.

I don't really plan on ever making a bigger machine because my projects are usually under two feet. Also, seeing as I will be in a dorm or small apartment next year I like this compact design especially with the folding stand. I do like the option of being able to move to a bigger machine though.

[NichB77]

I talked to my teacher who got me interested in building my own machine today and he tolde me I should look at the Xylotex kits. Does anybody know if these are good reliable parts or are they going to be half the preformance of the kits Ger21 told me to look into?

The one that I think would be best for me is 3 Axis System Kit. The steppers are slightly higher torque than the ones Ger21 pointed out. Will this be too much torque though?

The other option is 3 Axis System Kit, which is what my teacher used on his Solsylva 13x13. I thought this kit might not be enough for my 25x25, and for the same price I can get the bigger stepper motors.

Any input is helpful.

Thanks,
Nick

[ger21]

or are they going to be half the performance of the kits Ger21 told me to look into?

I actually use a Xylotex on my machine, since the G540 wasn't available when I built it.

I use 1/2-8 2 start screws, and can cut at up to 190ipm with it using 250 oz motors.

The G540 kit is well worth the extra $150. But, if you don't have it, the Xylotex is a decent drive.

But... two things.

1) Mine suffered from severe resonance, and I needed to add dampers to my steppers to make them usable. The G540 has circuitry to eliminate resonance.

2) The Xylotex (and almost all inexpensive drives) is susceptible to damage from miswiring. A wire coming loose from a motor connection is enough to kill it.

But once I made my dampers, mine's been running strong for a few years now.

Here's a video with and without the dampers.

Stepper Motor Damper Test. - YouTube

Stepper Motor Damper Test. - YouTube

[ger21]

If you do go with the Xylotex, it's a tough choice on which motors to get. I'd probably lean towards the 425's. Their max rpm will be quite a bit less than the others, but the extra torque at lower speeds will be good with the 5 start screws.

[adprinter]

Originally Posted by NichB77 I talked to my teacher who got me interested in building my own machine today and he tolde me I should look at the Xylotex kits. Does anybody know if these are good reliable parts or are they going to be half the preformance of the kits Ger21 told me to look into? The one that I think would be best for me is 3 Axis System Kit. The steppers are slightly higher torque than the ones Ger21 pointed out. Will this be too much torque though? The other option is 3 Axis System Kit, which is what my teacher used on his Solsylva 13x13. I thought this kit might not be enough for my 25x25, and for the same price I can get the bigger stepper motors. Any input is helpful. Thanks, Nick

Nick,
A VERY important point should be noted about the 3 Axis kits you referenced in your links. "The stepper motor drive board plays NO role in Home/Limit/STOP switch inputs, or various outputs, other than to provide screw point attachments to the parallel port I/O. See your software configuration setup for these types of I/O usages." Therefore, if you cannot afford a Gecko G540 kit right now, you should seriously consider waiting until you can! As the Gecko is already set up for wiring limit switches (which will prevent the machine from destroying itself) and are a great convenience for setting up the needed reference between computer and machine regarding the machine's actual physical location. While it is possible to setup the software to function WITHOUT limit switches, it is near impossible to achieve repeatable positioning without them. (In the likely event that you need to turn the machine off, and come back to it tomorrow for example).

[ger21]

Nick, A VERY important point should be noted about the 3 Axis kits you referenced in your links. "The stepper motor drive board plays NO role in Home/Limit/STOP switch inputs, or various outputs, other than to provide screw point attachments to the parallel port I/O. See your software configuration setup for these types of I/O usages."

I have Romans electronic home switches, a Super-PID with on/off and rpm control, and an autozero touchplate connected directly to my Xylotex. The only thing I need was a pullup resistor for the auto zero plate. It's not really a big deal to connect anything you want to it.

[NichB77]

Thanks for the warning adprinter. Another new thing I learned today. I have decided to go with the gecko package with the 387 oz-in motors. I might have to save up for a little while longer but Ger21 gave me a bit of information, which I will post later when im at my computer instead of on my phone, on why the 387 is better than the 425.

[ger21]

Get the 381's, not the 387's.

[NichB77]

This just further proves that I should be doing this from a computer not a phone. I have decided on the gecko package with the 381 oz-in motors. I will post the info that Ger21 gave me when I can access my computer later. Tomorrow I plan on talking to my teacher to make sure he has no other suggestions, which I don't think he will, and then the best part, sit down with my dad and talk to him about the "investment" I plan on making. Wish me luck.

[NichB77]

Just in case there are others out there trying to make similar decisions to the one I made on my stepper motors I will post what Ger21 told me that helped me decide which motors I wanted. Basically, motors with lower inductance lose torque at higher speeds than motors with high inductance. This means that a motor with lower inductance will have more torque than a motor with high inductance except for at low speeds. After doing more research I found that by looking at torque curves you can find which motors hold the highest torque at the speeds you plan on operating at. If anybody would like to add to what I think I've figured out feel free.