Newbie sanity check

[mmm]

Hello all! I've been fascinated with CNC machines for years and I think I finally have the resources to build one for myself. I've spent several hours reading these forums and looking at others' homemade CNC designs and I think I've reached the point where I'd like to throw my simple plan out there and make sure I'm not too crazy.

With a completed CNC machine, I'd like to be able to easily cut wood and MDF, up to say 2" thick. If I could cut thin aluminum that would be even more of a bonus. Speed is not a real concern for me. I love watching these things run and since this is not going to be a production machine (and will be housed in the garage) it can run for as long as it needs without disturbing anybody too much. On this starter machine, I'd like a travel of say 10" or 12" in the X- and Y-directions, and 3" or 4" in the Z direction. The accuracy doesn't have to be super at this point...I'd like to be able to easily cut out parts for another CNC without concern, or perhaps build a slick wooden clock as I've seen others do on these boards, but I'll not be working with very fine elements (at least not on this machine).

For the steppers and drivers, I'm looking at the KL-4030 package from Keling Inc. with 270oz bipolar steppers, 1.8deg/step, 32v @ 2.8a rating. The power supply is 36v/8.8a.

http://www.kelinginc.net/ThreeXCNCPackage2.html

This package is appealing for several reasons. The power supply is in a nice enclosure, although I could just buy one by myself. Same with the controllers. Additionally, the wiring diagram looks simple enough and at $359 it's definitely pretty inexpensive.

I haven't decided entirely on the frame yet, but I'm giving serious consideration to this one:

http://www.instructables.com/id/How-...-Cheaply-and-/

This is a simple design built with 1/2" MDF and parts mostly available from Home Depot or Lowes. This is very appealing because the instructions are laid out in great detail with pictures and lego-style diagrams, so will keep my frustration to a minimum, hopefully. Using this method, I should be able to purchase all of the parts from a local hardware store for about $250, get the Keling kit for $359, and end up with a working CNC for the low cost of about $750 and many hours of cussing and fist-shaking. (my total budget is about a thousand bucks).

My cutting tool will be a Dremel to start, as I have one laying about somewhere and it never gets used for anything. I'll likely buy something beefier after I get the machine up and running, but at this point I have no idea what.

Oh, and my home is a PC graveyard so no worries there. Since I don't know much at all about CNC software, I'm going to try real hard to love the Linux CNC software since it's free, but if that doesn't work out I'll spring for Mach3 which seems to have a very good reputation around here.

So my outstanding questions at this point (sorry for the novel):

1. Is the frame sturdy enough for cutting wood and possibly some very thin aluminum or brass? Pretend I've got a nice cutting tool that I got for less than $100.

2. Am I overlooking anything on the electronics side? I've got a parallel cable sitting around, but I think between that and the Keling kit I should have a ready to go system.

3. Am I going about this all wrong?

4. Does anybody have a CNC in Tampa or the surrounding area that could help me out with cutting out the MDF? If so, how much would something like that cost? I'll bring the board and the DXF! There are plans on the site for individual components or as one giant 48"x48" sheet.

Thanks for any -- and all -- comments!

[TOTALLYRC]

Originally Posted by mmm Hello all! I've been fascinated with CNC machines for years and I think I finally have the resources to build one for myself. I've spent several hours reading these forums and looking at others' homemade CNC designs and I think I've reached the point where I'd like to throw my simple plan out there and make sure I'm not too crazy. With a completed CNC machine, I'd like to be able to easily cut wood and MDF, up to say 2" thick. If I could cut thin aluminum that would be even more of a bonus. Speed is not a real concern for me. I love watching these things run and since this is not going to be a production machine (and will be housed in the garage) it can run for as long as it needs without disturbing anybody too much. On this starter machine, I'd like a travel of say 10" or 12" in the X- and Y-directions, and 3" or 4" in the Z direction. The accuracy doesn't have to be super at this point...I'd like to be able to easily cut out parts for another CNC without concern, or perhaps build a slick wooden clock as I've seen others do on these boards, but I'll not be working with very fine elements (at least not on this machine). For the steppers and drivers, I'm looking at the KL-4030 package from Keling Inc. with 270oz bipolar steppers, 1.8deg/step, 32v @ 2.8a rating. The power supply is 36v/8.8a. http://www.kelinginc.net/ThreeXCNCPackage2.html This package is appealing for several reasons. The power supply is in a nice enclosure, although I could just buy one by myself. Same with the controllers. Additionally, the wiring diagram looks simple enough and at $359 it's definitely pretty inexpensive. I haven't decided entirely on the frame yet, but I'm giving serious consideration to this one: http://www.instructables.com/id/How-...-Cheaply-and-/ This is a simple design built with 1/2" MDF and parts mostly available from Home Depot or Lowes. This is very appealing because the instructions are laid out in great detail with pictures and lego-style diagrams, so will keep my frustration to a minimum, hopefully. Using this method, I should be able to purchase all of the parts from a local hardware store for about $250, get the Keling kit for $359, and end up with a working CNC for the low cost of about $750 and many hours of cussing and fist-shaking. (my total budget is about a thousand bucks). My cutting tool will be a Dremel to start, as I have one laying about somewhere and it never gets used for anything. I'll likely buy something beefier after I get the machine up and running, but at this point I have no idea what. Oh, and my home is a PC graveyard so no worries there. Since I don't know much at all about CNC software, I'm going to try real hard to love the Linux CNC software since it's free, but if that doesn't work out I'll spring for Mach3 which seems to have a very good reputation around here. So my outstanding questions at this point (sorry for the novel): 1. Is the frame sturdy enough for cutting wood and possibly some very thin aluminum or brass? Pretend I've got a nice cutting tool that I got for less than $100. 2. Am I overlooking anything on the electronics side? I've got a parallel cable sitting around, but I think between that and the Keling kit I should have a ready to go system. 3. Am I going about this all wrong? 4. Does anybody have a CNC in Tampa or the surrounding area that could help me out with cutting out the MDF? If so, how much would something like that cost? I'll bring the board and the DXF! There are plans on the site for individual components or as one giant 48"x48" sheet. Thanks for any -- and all -- comments!

Answer to your questions in the order in chich you posted them.

1. Not really. the mdf will more than likely not have the rigidity to cut alum.

2. I may sound like a broken record around here, but for the extra couple of hundred, go Gecko G540. Keling has a nice package on his site.
It has an integrate breakout board and other nice stuff that makes it worth every penny.
You will keep it forever.

3. Slightly. There is a lower limit to how slow you can go and not burn the cutter or material. This machine will obviously be a learning experience and you will graduate to a "real" machine from here. Don't cheap out on the electronics as I think it is a false savings.
You will misc wire to hook stuff up.
DON'T FORGET THE BIG RED ESTOP SWITCH.
It should be one of the first things that you wire up.

4. I can't help as I am in CT.

My other thoughts

1.Use a computer case to house all of the components to keep the dust off of them, since you are in a pc grave yard.

2. Dremels are great to learn on and do light cutting, they would probably take for ever to go thru 2" material if at all.

3. A router will make short work of heavier stock, but you mdf frame may not have the strength to handle the work load.

4.Mach3 is free to try so I would try it and emc2. If you like dos turbo cnc is an option. there are others out there.

5. Read as much as you can here on the zone and elsewhere.

6. Have fun and ask questions.

Mike

[mmm]

Thanks for your comments! As I mentioned, my budget is about a thousand for this project (and you are absolutely correct that this is kind of a "gateway CNC"), so the reusability of the electronic components is definitely important. Looks like they have a Gecko 540 kit for $550:

G540 4 axis package (1PCS G540 +4 pcs KL23H2100-30-4B (3/8” Dual
shaft with a flat) 382 oz-in + 1 pcs KL-350-48 48V/7.3A 110V/230V
power supply): $549.95

I have heard a lot of good things about the Gecko products, and although I couldn't tell you one bit about how they are different from anything else, I think I will be thanking myself in a year if I spend the extra $180 on this set instead.

Too bad I won't be able to cut aluminum, but it's not the end of the world! And a great excuse to build another CNC down the road.

Since I have your ear, can you recommend a good replacement for the Dremel for this application, that would work well with MDF and give me a little more cutting power?

Thanks again!

[ger21]

Originally Posted by mmm Since I have your ear, can you recommend a good replacement for the Dremel for this application, that would work well with MDF and give me a little more cutting power? Thanks again!

Variable speed version of the Bosch Colt.

[TOTALLYRC]

Originally Posted by mmm Thanks for your comments! As I mentioned, my budget is about a thousand for this project (and you are absolutely correct that this is kind of a "gateway CNC"), so the reusability of the electronic components is definitely important. Looks like they have a Gecko 540 kit for $550: G540 4 axis package (1PCS G540 +4 pcs KL23H2100-30-4B (3/8” Dual shaft with a flat) 382 oz-in + 1 pcs KL-350-48 48V/7.3A 110V/230V power supply): $549.95 I have heard a lot of good things about the Gecko products, and although I couldn't tell you one bit about how they are different from anything else, I think I will be thanking myself in a year if I spend the extra $180 on this set instead. Too bad I won't be able to cut aluminum, but it's not the end of the world! And a great excuse to build another CNC down the road. Since I have your ear, can you recommend a good replacement for the Dremel for this application, that would work well with MDF and give me a little more cutting power? Thanks again!

The major benefits to Geckos are as follows.
1. Unparalleled support.
2. Mid band instability compensation. electronically prevents the motor from stalling unless you overload it.
3. Quite operation. will not buzz and squeal when idle like chopper drives.
4. Morphing from microstep to full step on the fly. This gives the best resolution at low speeds and max torque at high speeds.
5. 50v operation for great rapids fom a low priced package.
6. 4 axis drivers included
7. Integrated breakout board for computer protection.
8. Integrated 0-10v anaolog output to drive a vfd/dc motor control. great for that mill and lathe in your future.
9 Did I mention the great customer support.
10.Very conservative ratings on internal components so risk of failure is minimal.

Originally Posted by ger21 Variable speed version of the Bosch Colt.

Tha looks to be a nice router. Aluminum so it won't flex and a round housing to make it easier to mount.

I have used both the Dremel (Not good), and rotozip with plastic housing (better but still lacking). I am working on mounting a 2hp router to my cnc router and I will see.

[mmm]

This is a possibly stupid question, but the design that I'm looking at building is only a three-axis model. Can I run the G540 using only X, Y, and Z, and later build a new machine that incorporates the fourth axis?

I was able to find the Bosch Colt variable speed on eBay for about $120 shipped on eBay...not bad! Including that and the G540 package from Keling, it looks like my cost (after taxes and shipping) should be somewhere in the $1100 neighborhood. That's right on budget (my budget didn't include the tool purchase).

Another question -- with this tool and the G540 kit, is the limiting factor for cutting aluminum or other soft metals going to be the stability of MDF? In other words, is it feasible to take the electronics, steppers, and router that I have listed above and move them into a sturdier frame table down the line and be able to cut metal? My biggest concerns are the steppers and other assorted electronics (like the power supply) -- if they don't move to another CNC setup after my first, they'll collect dust or just be passed to a friend, whereas the router can certainly find more use.

Thanks so much for all the help you all have given so far...going on a cruise later this week and next Sunday is my birthday, so I'll finish up my decision making by then and take the plunge!

[ger21]

Originally Posted by mmm This is a possibly stupid question, but the design that I'm looking at building is only a three-axis model. Can I run the G540 using only X, Y, and Z, and later build a new machine that incorporates the fourth axis?

Yes, you can only use the ones you need.

Originally Posted by mmm Another question -- with this tool and the G540 kit, is the limiting factor for cutting aluminum or other soft metals going to be the stability of MDF?

Machine rigidity and possibly the spindle will be the limiting factor. Depends what "other soft metals" are. you may find you need to use coolant to cut some metals, which doesn't mix well with mdf machines. And while you can take very light passes, metal usually requires slow spindle speeds and more power. But I have seen people cut aluminum parts with a dremel, or Rotozip, so technically you should be able to cut what you want, but results can vary.

[TOTALLYRC]

Originally Posted by mmm This is a possibly stupid question, but the design that I'm looking at building is only a three-axis model. Can I run the G540 using only X, Y, and Z, and later build a new machine that incorporates the fourth axis? I was able to find the Bosch Colt variable speed on eBay for about $120 shipped on eBay...not bad! Including that and the G540 package from Keling, it looks like my cost (after taxes and shipping) should be somewhere in the $1100 neighborhood. That's right on budget (my budget didn't include the tool purchase). Another question -- with this tool and the G540 kit, is the limiting factor for cutting aluminum or other soft metals going to be the stability of MDF? In other words, is it feasible to take the electronics, steppers, and router that I have listed above and move them into a sturdier frame table down the line and be able to cut metal? My biggest concerns are the steppers and other assorted electronics (like the power supply) -- if they don't move to another CNC setup after my first, they'll collect dust or just be passed to a friend, whereas the router can certainly find more use. Thanks so much for all the help you all have given so far...going on a cruise later this week and next Sunday is my birthday, so I'll finish up my decision making by then and take the plunge!

Not stupid, it is a very valid question. and yes you will be a ble to run it as a four axis(mill or router with 4 axis), three axis (mill/router), two axis (lathe), one axis (bandsaw) I am going to do my bandsaw someday, just because I can.

The electronics will be very suitable for a wide range of machines that your are likely to own.
The limiting factor on cutting harder materials than wood is the rigidity of the machine. And just to be clear, you will be ble to move them to another machine. You can also set it up so you can run more than one machine just by switching wires and stuff.

Have a nice cruise and I hope to hear from you when you get back.


Mike

[CarveOne]

Don't forget that the 4th axis board (G251) can be used to replace one of the other G251 boards in the G540 assembly if one goes bad for any reason (though these little boards are well protected electrically). The bad board can be sent back while you continue to have three working axes.

Hmmmmm, I kinda like the idea of an x & y axis table on my 22" throat scroll saw. CNC marquetry anyone? Cheaper to build and operate than a laser cutter.

CarveOne

[mmm]

Good morning!

After much thought, I've decided to bite the bullet. I'm going to get a table router kit from Modular CNC ($310), a Gecko G540 from Gecko ($299), and some 382oz/in steppers from Keling as well as the power supply.

First, does this look like a decent starter setup? I'll be milling a new CNC eventually from these parts, but for now I'm just going to be learning how to use the machine and working with some simple wood stuff.

Second, I see that the G540 has a DB9 connection for each motor. Is there a decent place to get these cables pre-made for the motors or should I pretty much be making these myself? I don't mind spending a couple extra bucks to save the time.

Oh yeah, and is there anywhere else I should be shopping for this stuff? I've had a surprising amount of trouble sourcing these things elsewhere...

Thanks all!

[TOTALLYRC]

Originally Posted by mmm Good morning! After much thought, I've decided to bite the bullet. I'm going to get a table router kit from Modular CNC ($310), a Gecko G540 from Gecko ($299), and some 382oz/in steppers from Keling as well as the power supply. First, does this look like a decent starter setup? I'll be milling a new CNC eventually from these parts, but for now I'm just going to be learning how to use the machine and working with some simple wood stuff. Second, I see that the G540 has a DB9 connection for each motor. Is there a decent place to get these cables pre-made for the motors or should I pretty much be making these myself? I don't mind spending a couple extra bucks to save the time. Oh yeah, and is there anywhere else I should be shopping for this stuff? I've had a surprising amount of trouble sourcing these things elsewhere... Thanks all!

The G540 comes with the db9 ends because you have to put the current limiting resistors in the line. You could possibly use standard cable and cut the ends off, but I don't know what everyone is doing.