This Husker finally started building!

[nuplowboy]

At long last, I've begun the contruction of my first CNC router/dremel!

After giving it some thought and thanks to some folks from the zone, I've decided to slap together jgro's design for my first attempt. I can then use that machine to make patterns for aluminum castings to make a more durable version with potentially more range. It'll also let me experiment so I better know what the Aluminum machine should be. (what size steppers, lead screw pitch, spindle type, etc)

Work began on Saturday as I hacked up the MDF into pieces roughly the sizes shown in the plans. I say roughly because Home Depot did some of the cuts and let's just say I'll have to adjust a few dimensions... That's just one more reason to upgrade to a big-ol' cabinet table saw someday...

Today I slept in, then went to work. I was able to get the base and bed torsion boxes glued up. Then, I ran out of Gorilla glue. And, I got hungry. I'd post pics, but we've all seen MDF boxes!

More to come, I've got money in this thing, I'm committed now!

[nuplowboy]

Due to other commitments (work, basketball league) Nothing was done on the cnc project today. However, this is fortunate, because the quality of the work was poor.

With any luck, progress will happen tomorrow afternoon.

I do have a couple of questions...

1. What is the most economical (cheap) software for converting 3D CAD models (STL, etc) to G-code? I have found a couple and the best bet so far is MeshCAM (~$100) Are there others out there I have not run across?

2. Does anyone have a supplier/part# for a good, simple N.C. home/limit switch they've had good luck with? Again, since I'm...err "thrifty", I'm looking for low-buck but decent.

Thanks! More to come and pictures whenever I get something that looks less like a pile of MDF!

[ger21]

Originally Posted by nuplowboy 1. What is the most economical (cheap) software for converting 3D CAD models (STL, etc) to G-code? I have found a couple and the best bet so far is MeshCAM (~$100) Are there others out there I have not run across?

There site was down when I just checked, but STLWork was on sale for $75. Not sure if it still is, though. http://www.cadcamcadcam.com/ I believe there is a demo you can try.

Almost forgot. FreeMill. http://www.cncportal.com
It's free, but a pain to use due to the almost nonexistant options. Depends what you're making, though.

[nuplowboy]

Well, tonight there was some progress. All adjustment blocks are drilled and tapped. I also dug out the router to start on the dados in some of the parts for the Y and Z. MDF is a real pain in the rear. Oh well. Progress is pretty slow since after getting home I have to fire up the heater in the shop and let that go for an hour so it gets up to a decent temp.

Ger21... I downloaded FreeMill last night, and checked out the other. Thanks for the links, they look promising. The price for FreeMill is definitely in my price range although I will probably upgrade to MeshCAM or STLwork later.

A question about FreeMill. I was playing around with it today and it has bunches of options for postprocessing. I've been figuring on running TurboCNC or a similar program to feed the 3-axis controller from HobbyCNC. My question is, which postprocessing option in FreeMill gives me the G-code or whatever that works (best) with TurboCNC?

[nuplowboy]

Things are starting to look like a machine. After a couple half-days of workin' on it this weekend, I have the base, table, and gantry pretty close to ready. Below are pics of the base/table and gantry as they were last night. Today I finished up some of the gantry glue-up. I also painted the table and the underside of the base (hammered black on most, silver/grey for the working table surface) and started drilling parts for the X axis carriage. That work's about 75% ready for glue.

Also bought the ready-rod and pipe this afternoon, Will have the gantry on the base rails as soon as I machine the angle-iron to hold the skate bearings. I'm using steel for the bearing supports instead of Aluminum. This is partly for strength and rigidity. The other reason is laziness, I can cut steel easier with my chop saw and I can always weld the excess into some other project!

[stevec]

nuplowboy,
Looks Great so far!

You are building alot faster than I did. I am building the same machine for my first build and the mdf cutting and building is now done, now I am working on the smaller stuff like the backlash-nuts. It's intresting to know that someone else is working on the same project at the same time and going through the same pains. I will take a photo of mine today and post it here for your viewing. We may be able to help each other in getting these up and running. I am still unsure about software, motors and a controller. I was thinking about using the hobbyCNC kit. What do you plan to use?

Steve

[dwwright]

I built the same machine about a month ago. I used the hobbycnc board and 80 oz/in. motors, but I'd recommend either the 127 or 200 oz/in that he sells now. I started out with a AT power supply but soon upgraded to a 24 V that I found on ebay. I'm now looking at modifying a amp power supply to get 35 to 40 volts out of. JGRO's design has plenty of adjustment built in to make it accurate. I thought about doing the steel angle iron myself, but I found that the aluminum was much easier to mill with the wood equipment I have. By the way, I didn't install home/limit switches as I haven't found that I need them. I may wire a emergency stop switch eventually to the limit switch. Other than that, most of the stuff I mill is within the table limits and it doesn't move fast enough (10-15 ipm) to cause much concern.

Darren

[stevec]

dwwright,

Do you recommend getting the hobbycnc chopper driver kit for $79.00 or should I get the package kit for $120.00. It's a $41.00 difference and not sure if it's a savings or get the other parts locally. Also, should I look to ebay for the stepper motors or get them at hobbycnc as well? And where do I get the power suppy.

Thanks
Steve

[dwwright]

Originally Posted by stevec dwwright, Do you recommend getting the hobbycnc chopper driver kit for $79.00 or should I get the package kit for $120.00. It's a $41.00 difference and not sure if it's a savings or get the other parts locally. Also, should I look to ebay for the stepper motors or get them at hobbycnc as well? And where do I get the power suppy. Thanks Steve

Looks like the kit is a good value. I spent $30 for wire alone, fans are usually around $10 - $15, not to mention the other power supply parts. However Old stereos (with high output) and old amplifiers are good sources for power supplies and you can sometimes find them at antique stores for a good price. Check around at an office park to see if they have any old telephone equipment, they usually have some 24v power supplies with them that would work also. I guess it depends on how resourceful you are and if you want to build the power supply. Dave's price for the motors w/the board are a good value and he would probably be more likely to support them, but he's pretty helpful otherwise too.

Additionally, the next time around I'll do the 4-axis board. I regret not buying it the first time as I'd like to setup for spinning some table legs and such. Although you can add another motor and plug it in place of the x or y axis.

Just my thoughts and ramblings....Hope this helps

Darren

[nuplowboy]

I already have a hobbyCNC kit with the 80 oz steppers from about a year ago when I got semi-serious about building a machine. I got as far as to build the controller and PC power supply and attempt the first aluminum casting. That casting failed back in August/September and sort of took the wind out of my sails. I got motivated again and with the weather, figured the MDF plan was the best for a first run.

As far as build speed, I'm not being nearly as picky with details as I would normally be. I figure a CNC router with bad accuracy (bad for CNC) is still way better/easier than me cutting out patterns, etc by hand. You can build a pretty decent piece of furniture with 0.031 accuracy! The next machine will be much more rigid (all aluminum) and stronger and will be built with better precision. I'll probably upgrade to bigger steppers for the next one too, so I can tackle the occasional aluminum part or go faster in wood.

[stevec]

Here is a few shots of my jgro special. The last photo is a cheap cutting board I got at Walmart (.99). I am building the anti-backlash nuts (try) with it. Not sure if it will work, I read someone on this board say it will.

Steve

[nuplowboy]

No progress Monday, very little today. I did paint the top of the base. I started fab on the angle iron bearing supports for the Y axis. As I mentioned, I went with steel. Drilling the holes was no problem, but then I got to the spot faces to recess the cap screw heads. Using a file wasn't very appealing (laziness kicked in) and I hated to take the grinder to it and get a less-than flat surface. Then, a solution hit me . I know plan to weld the head of the cap screw to the inside of the angle iron. This will leave the outside ridge clean and eliminate the need to hold the head of the screw while tightening/adjusting. I tacked one in place to test the plan before retiring to the couch for Biker Buildoff. (Darn Discovery Channel really cuts into my hobby time!, American Chopper, American HotRod...) Problem solved...