A few questions (pre-build / planning)

[rdfl]

Hi everyone,

I've only recently been poking around the forums but I'm very interested in building a MechMate. I'm still in the pre-planning stages while I try to absorb all the information and read through the forums but I wanted to throw out a few quick questions that if nothing else, will help me decide which areas to research next.

First, concerning the "control box" and other electronics...what else is included there other than the geckos, PMDX and power supply?

Again, I'm still looking through the vast amount of info here but I need to latch on to a few more key words to guide me along right now.

Second, in very general terms, what's the best way to start? I noticed that the forum areas are numbered starting with the table and ending with the software. I also noticed many posts discussing the "kitchen table" system for testing.

I can't order all my parts in one big $8000 lump (assuming I had already become familiar with everything) but I also don't want to build the bulk of the mechanical unit only to have it not be touched (and take up a good amount of floor space) while I tinker with the electronics. Finally, as much as my budget will allow I'd like to have a continuous flow of things to do on the project so I don't wind up with a 3-week span while I'm waiting for a special order item.

Hopefully, I avoided the typical newbie pitfalls here and I look forward to hearing everyone's thoughts and learning more about the project.

Thanks for reading.
Rick

[sailfl]

Rick

Welcome to your build.

It is the same for all of us. Where to start. What size table do I want to build. Reading as much as you can and downloading the plans and printing them off is an important step. They will become the book that you will get to know well.

You don't have to start with the table. Some start building the kitchen table project first and it takes up a lot less space. Most of the parts in the controller box are resaonably priced. The motors cost a little more.

Read threads and ask questions. Members will help you when you hit a wall. It won't be long before you will be cutting and helping others. That is the way this place works.

Good luck.

[rdfl]

sailfl,

Thanks for the welcome and encouraging words.

-Rick

[jhiggins7]

Rick,

Welcome to the Forum and good luck with your build.:)

You asked:
...First, concerning the "control box" and other electronics...what else is included there other than the geckos, PMDX and power supply?...

Beyond the three items you mention, some folks add a Solid State Relay to control a Router. In addition, there is a Disconnect Switch and a Contactor. The Contactor is latched through one of the E-Stop circuits and can be deactivated by hitting one of the E-Stop buttons or, of course, the Stop Button.

You will also need to provide power to the PMDX.

In my case, I added a dual 12 & 24 volt power supply and a Relay Board to allow me to control a Router, Dust Collector and Hold-Down Vacuum using 24 volt DC Contactors.

As for where to start, I started with the Control Box. Partly because I'm more familiar with electronics than metal working, but also because I bought some used OM Vexta Stepper Motors and I wanted to make sure they would work.

Regards,
John

[rdfl]

John,

Thanks so much for the info...I've latched onto a couple key words you said and I have a few follow-up questions if you don't mind.

First, you said that I would need to supply power to the PMDX. Does it require it's own dedicated power supply?

Second, you said "some folks add a Solid State Relay to control a Router". In what way are you using the term "control" here? I assumed that Gecko's took care of the signals to the router...is there something more?

Next, you said you added a "relay board". Can you link me to any general image of this? I'm picturing some type of terminal block/strip...am I way off base here?

Also, I'm hoping you can offer one more bit of info. I see lots of talk about the Delta VFD but it seems that it's only being used with a spindle and not a router. Is that correct? Is it optional for a router or just totally unnecessary?

Again, I admit I still have lots of reading to do so if you don't have a quick answer but can point me to another thread that would be great as well.

Thanks for your time, I look forward to reading your replies.
-Rick

[Gerald D]

Power for the PMDX (http://www.mechmate.com/forums/showthread.php?p=3548&postcount=14)

Second, you said "some folks add a Solid State Relay to control a Router". In what way are you using the term "control" here? I assumed that Gecko's took care of the signals to the router...is there something more? Gecko's only look after the stepper motors, not the routers (unless you are using a Gecko 540, which is not the most common choice. . . . yet). The PMDX gives the on/off signal to a router - but you need a heavier switch to handle the amps. Some folk use a Solid State Relay, some use another contactor.

Relay board is for the limit/home switches at the "ends" of the rails . . . . if you are using limit/home switches. Some of us don't.

VFD's are only for spindles - they cannot be used with routers.

Right, now you should have a lot of reading to do - see you again in a week's time! ;)

[rdfl]

Gerald,

Thanks for taking the time to poke into my newbie thread. :)

I think that the "kitchen table" approach will be best for me. I have a much more concise visualization of what should be taking place in the control box...so now I can start looking over the dozen or so items that I need to do more in depth research about...and keep reading the forums of course.

Thanks again,
Rick

[domino11]

Welcome Rick!
Hope you like to read! :)

[Gerald D]

The "must-read" threads are the ones on the blue background at the top of each sub-forum.

[rdfl]

Gerald: Thanks, I had figured that one out already. :)

Domino: Thanks for the welcome.

[jhiggins7]

Rick,

Gerald answered most of the questions as I would have...he's up at the crack of dawn, eight hours earlier than we who are a third of the globe away.:D

The exception is the following:
[QUOTE=Gerald D;21302...Relay board is for the limit/home switches at the "ends" of the rails . . . . if you are using limit/home switches. Some of us don't...QUOTE]

In my case the Relay Board is to provide additional control for a Dust Collector and a Vacuum Hold-Down. The PMDX, as you've probably read by now, has 1 relay which many people use to control the Router SSR (or Contactor). I'm also planning to "turn-on" a Dust Collector and Vacuum Hold-Down using MACH3 and the PMDX to energize Contactors via the Relay Board.

I don't have pictures with me right now, but if you are interested in this Relay Board, I can share the design and pictures with you next week...or whenever you are ready. Just let me know.

Regards,
John

[rdfl]

John,

Thanks for the information. I'm thinking that I will want a vacuum hold down but it's too early for me to worry about that. I would think that I can just clamp down material if needed at first just to make sure the machine works correctly.

I would love to see whatever pictures and design info you can share. Even if it's not something I'm going to incorporate right away I would want to make sure I keep it in mind when making the control box layout/wiring and make sure I account for it when planning my budget.

Thanks again for replying.
-Rick

[jeffh]

Hi Rick! And welcome.

If you're looking for a couple of good threads to get the juices flowing and to
describe the whole process from start to finish, take a look at SMReish's thread in the "Mechmates already cutting" section of the forum. I think it's called: "Hectically in Production" or something similar. This thread provides really good details on a start to finish build.
(Actually, all of the threads in the "already cutting" section are really good sources of photos and information)

For the control box, I'm sure you've already seen the "Kitchen Table" thread but Gerald also has another thread that is very helpful as well. It's called:
"Mechmate DIY Control box full spec screened spindle 3phase export". The pictures are worth a thousand words.

And lastly, There's a basic diagram around here somewhere that Gerald (I think...) created that describes what all of the guts of the control box do.
I can't seem to find it after a quick search but if I do I'll post a link here.

Good luck with your build. Say goodbye to all your idle free time :)

-Jeff

[Gerald D]

Basic Schematic of what a Control Box does (http://www.mechmate.com/forums/showthread.php?t=278) ?

[jeffh]

Me again....

I found the diagram/thread that Gerald did (don't know how I missed it the first
time through...)

It's this thread: http://www.mechmate.com/forums/showthread.php?t=278

See also: http://www.mechmate.com/forums/showthread.php?p=3668&postcount=7

But be sure to read the whole thread! There's a lot of detail required for the control box and plenty of shock hazard so be careful.

Hope that helps.

[rdfl]

Hi Jeff,

Thanks for the welcome and info. I had already scoped out the threads you mentioned and added them to my reading list. I have not ventured too far into the Mechmates Cutting forums yet but after a quick look at the SMReish thread I can see it will be another great source of info...thanks for the heads up!

I already got ahold of the control box images but thanks to both you and Gerald for linking me to them.

As for my free time, I said good bye to it long ago. However, now I'll be saying good bye to my extra money as well...this is not going to be a cheap project. Maybe my wife won't notice? :D

Thanks again,
-Rick

[jeffh]

Sure Rick, You're very welcome!

Ahh I see Gerald beat me to the post!

(Where DOES that guy find all the time to do this and everything else he does?)

And you're spot on: You're wallet will get slightly thinner (although, In my opinion, this Mechmate is both the best AND least expensive CNC Router solution)
and, at times, you're wife won't be thrilled. Mine wasn't/isn't... :eek:

The best thing about this project is all the "Other" stuff you'll learn how to
do. That, to me, is better than the finished project.

Keep us posted with your build!

-Jeff