[Jkountz]

Ok guys and gals after years of pouring through these forums and designing several really nice yet very expensive machines, I have decided to start humble with my 1st CNC endeavour.
I came across the build thread here for the Grunblau MDF 3790 and the more I looked at it the clearer it became that is where I would start. This is a really nice machine made from MDF and boasts a cutting size of 37x90 inches. The plans were affordable so I bought them a while back and have been studying them ever since.
Brian (the original designer and builder) has been very helpful answering my many questions and pointing me in the right direction.
Im in the parts gathering phase at the moment and have been making purchases like a mad man the past couple of weeks.
So far I have ALL the standard nuts and bolts, the motor/driver/psu package, the aluminum rails and the bearings, cable and connectors etc. This weekend Im going to pick up the MDF and start the actual build. I am playing around with the electronics enclosure getting everything placed and secured before wiring everything up.
I will be using R&P for the X and Y axis where as the original design used acme screws. Still have some details to work out there but nothing major. :banana::banana:Here are some pics to get this build thread started, not much to look at right now but its coming, finally its going to happen!!

[dodger889]

Just a quick note. Those power supplies you should use a master power switch and off the power supply itself use and e stop switch to kill any motion. That switch could be use also for an idle switch for the motors during Mach3 power ups. Then in the BOB use that e stop to just stop everything including Mach3 . So in effect you could have 3 e-stops all doing different ways of stopping the machine..

[Jkountz]

I planned for a master power switch and of course an e-stop already. Im not sure I follow you on the idle switch for the motors during mach power ups. Shouldnt everything be off while Mach is starting anyway? Or did you mean something else?

[dodger889]

When you start up those drivers apply power to the motor and they start to heat up with that power supply and driver combo. If you look at the power supply there is a jumper that will allow for the remote control of on off of the power output.

[Jkountz]

Ah ok I will take a look at that, thanks for pointing that out!! Got more parts in today and the MDF is coming this weekend, cant wait to get started actually building the machine!!

[PaulRowntree]

When you start up those drivers apply power to the motor and they start to heat up with that power supply and driver combo. If you look at the power supply there is a jumper that will allow for the remote control of on off of the power output.

My G540 instructions tell me not to have any switches between the power supply and the G540. I always assumed that the G540 doesn't like rapid voltage changes. I don't know about other Gecko drives, or if the output enable behaves like a switch.

Cheers!

[ger21]

I don't know about other Gecko drives..........

Never switch the DC on any Gecko drives, or probably any others for that matter.

[Devastator]

Never switch the DC on any Gecko drives, or probably any others for that matter.

My hobbycnc EZ driver kit came with two power switches, one for the AC and one for the DC. I've always wondered about that since I hear it can cause problems with other driver boards. I've never had a problem with it, but I certainly would not flip the switch with the motors running to find out. Same goes with attaching it to the e-stop.

[Jkountz]

More progress today albeit slow and steady. I picked up all the MDF for the project and my back is really mad at me now! I had the full sized patterns I got from Brian printed the other day and got busy laying out some of the smaller pieces. Got a few cut out. Im loving the full size patterns, a bargain at twice the price folks seriously. Just stick them to the blank and have at it with the bandsaw and final shape/sand on the disc sander. The patterns are laid out in such a way that optimizes the sheets of MDF for the best yield. For example all the 6" wide pieces are together so you can just rip one long piece then cut the parts to length and mark any holes with a center punch. Done deal!
Heres some pics of todays progress.

[Jkountz]

Todays progress. I got the table top drilled (lots of holes to drill!) and cut out the lower half of the table. I also got the gantry uprights cut out and shaped to size. Its coming along faster that I thought, I should be able to start some assembly of all these components in the next day or so. Still waiting for some hardware to get here but plenty to do in the meantime. I need to learn more about Mach3 and motor tuning. Some good bedtime reading there for sure!!
Heres a couple pics for ya.

[HungryArie]

To gain a better accuracy of the holes you could considering placing the items onto each other and drill two holes in one go.

[Jkountz]

To gain a better accuracy of the holes you could considering placing the items onto each other and drill two holes in one go.

Yep, already ahead of you there, only way I know of to make sure everything lines up!!

[Jkountz]

So today I started some actual assembly, I got both bearing block assemblies done and the router mount or mandible if you will. I also got all the holes in the lower table drilled. Its slow going but Im not in any hurry really, just taking my time and trying to avoid any big mistakes!!
Some pics of todays progress.

[azide_0x37]

Looks like you're just a bit further along than me on this build. And updates recently? Oh, and how are those drivers interfacing with the CAD/Cam software? I've got identical ones, just haven't tried setting them up yet...

Should do that today...

[Jkountz]

Ive been slacking in the picture taking department, sorry about that! I have alot done since the last time I posted, darn holidays and that stupid thing called....what is it again?? Oh yeah WORK, keeps getting in the way of my cnc fun.
But I have managed to get some things done. The table top is done as is the frame of the gantry. I got part of the Z axis together this morning and hope to finish that up today or maybe over the weekend. Now I just gotta figure out how to get all the stuck paper off my parts. Sanding seems to be in my future....Yeah boy how I love to sand MDF.....

Its getting there, more to come later....

[Jkountz]

Z axis is almost complete now I just gotta figure out my R and P drive for the X and Y. I think I have a workable model but wont know for sure until I try it. I am waiting for the rack to arrive any day now so it wont be long!
Heres a short video showing how smooth everything is working so far. Its like buttah...!!

[Trotline]

Very nice! You're within "spitting distance" now.

A comment / request: The torn paper on your Y-axis looks remarkably cool. ( guessing that's why it's still there.) Please keep that! It's better than any slick paint job you could get done. Just do something to preserve it, like clearcoating, etc..

Keep up the good work!

Luke

[Jkountz]

Thats funny trotline, youre not the first one to tell me that!! I guess I might just have to keep it on there now!! LOL
Thanks for the comments!!

[Jkountz]

I have been toying with the electronics for this machine and I have a simple question for anyone who may know. On my drivers there is listed RMS and Peak amps. My motors are supposed to be rated a 3.0A. Should I set my driver to RMS or Peak and should I use a setting just under or over the 3.0A rating? (there is no 3.0 even rating)

[cambosoup99]

I have been toying with the electronics for this machine and I have a simple question for anyone who may know. On my drivers there is listed RMS and Peak amps. My motors are supposed to be rated a 3.0A. Should I set my driver to RMS or Peak and should I use a setting just under or over the 3.0A rating? (there is no 3.0 even rating)

If its rated at 3a, I wouldn't go over that.