3-Axis Stepper Controller

[MP1]

Greekpic,
The pin assignments were setup to match generic software packages. If I understood correctly, then the pulses from generic packages such as DanCad will no longer work.
I did the same thing several years ago and wrote my own software. It was not until later that I realized my board with the pin assignments that I chose would only work with my software. This was not a big issue, but I ended up changing the pin assignments (and re-writing my software) so that I was not restricted to only one software package on my machine.

MP

 

[GreekPIC]

In most software packages you can change the pin assignment. I use TurboCNC and it does that, so does CNCPlayer which I've also tried. I haven't tried Mach2 but from what I've heard it does too. As a matter of fact it comes as a surprise to me that there are programs out there that don't give you this option.

 

[MP1]

Yes, there are some programs out there that do not allow for this. That is what makes it necessary for a particular pin out when making a "one size fits all" type of board. Otherwise you get a lot of grumbles from those who use such limited software.
Since you have the capabilities with all of your software programs, then this will not cause you a problem. I only wanted to point this out as a "heads up" for those who might use the new board and have a problem. I have a small LED board that I made years ago. I slow down the pulses so that I can see them and plug the board in to see what is lighting up before adding ANY new hardware to the computer. A good tool to have on hand. I highly suggest this to anyone making the CNC projects.

MP

 

[GreekPIC]

Could someone help me with this? There's one in every hand drill.

I thought it was a capacitor (it says 0.33uF on the case) but I measured it with my DVM and it was not.

 

[Dazza]

Hi GreekPIC ,

This link may give you some answers(http://www.dse.com.au/cgi-bin/dse.storefront/4292562d0a01eeac273fc0a87f9c06ed/Product/View/R2620) .

 

[GreekPIC]

Ok, thanks. So, if it's a cap, why doesn't my DVM agree with the nominal value?

 

[EdwardM]

Hi GreekPIC

this link will give the the complete answer as to why the DVM reads anywhere between 470k and 2.7M Ohms
http://www.pge.uk.com/PGE/pdf/KNB153x_R.pdf

Ed

 

[GreekPIC]

Oh, now I see, not just a capacitor, thanks.

 

[GreekPIC]

I also wanted to report my experiences from using this board:

-First of all the ver2.0 board will plug-in connectors makes it a lot easier to use. While seting the machine up you will need to rewire often. Having to unscrew ~20 terminals isn't fun.

-It runs really cool. With printer steppers at 15V and heatsinks on the UCN's I had it running for 3,5 hours, moving the table diagonaly back and forth. Temp at the heatsink was ~30

 

[EdwardM]

Hi GreekPIC

I've been promising myself for years that I'd build a CNC machine  real soon now.

With printer steppers at 15V and heatsinks on the UCN's I had it running for 3,5 hours, moving the table diagonaly back and forth

Apologies if you've already done so but could you post a picture of the mechanical aspects of the machine?

Thanks

Ed

 

[GreekPIC]

Well what I'm building now is just a test bed. I want to work all the details out so when I make the "real deal" there'll be no surprises.

It's made out of everything I could find for free or really cheap. The body is melamine particle board (gift), the ways are ball bearing drawer slides, the motors from a scrapped printer, the spindle motor from a busted jig saw. The leadscrews are M8 threaded rod (gift).

Ver2.0 machine will have aluminum frame, THK rails, ballscrews, 3ph spindle motor and VFD.

If you need something small (e.g. fpr milling - drilling PCB's) I would suggest using rods & plain bronze bearings for the ways. There are nice rods where the steppers came from... ;D

View attachment 37074

 

[Dazza]

Hi GreekPIC ,

Very nice work , I have been planning to go the same way about it, start off with some think simple to become familiar with the whole process, then go on to the real deal 8).

I have been dreaming up all sorts of ways to make a starter project, but I do like yours and it would be really nice and I would appreciate it, if you could provide a few more picks of the really good parts.

And I'm sure you know what I mean by the good parts ;D ;D.

 

[GreekPIC]

Here you go, I think this makes it clear:

View attachment 37080

 

[GreekPIC]

Both leadnuts (X&Y) are bolted on the middle plate (you can see the X one and the bolts that hold the Y one. They are made from aluminum.

-Lesson #1. Use Derlin for leadnuts. I thought the screw would wear the nut out to a point that binding will be minimized but its 7075T6 aluminum and I'll wear out before it does.

You can see the motor support (laser cut & CNC bent) and the home/limit switches.

-Lesson #2. Use timing belts to connect the motor to the screw. Otherwise the allignmen requirements will be very high.

You can aslo see the ball bearing drawer slides. The middle plate slides along the Y axis over the base, the top plate (table) slides along X over the middle plate. Z uses the same slides and holds the chuck of a flexible drill shaft. The spindle motor is inside the body and this way the Z motor doesn't have to carry its weight.

On top of the machine you can see the red emergency stop button and the start button. They operate a relay inside.

 

[Glass-Giant]

Hi,
Newbie here.  I've been thinking of building a cnc mill for foam for a year or two now. I bought all the stuff for this board over the last year and stuff for a simple metal detector. Doing the metal detector now, as I've never made a pcb before.  Will be starting the mill within the month.

-First of all the ver2.0 board will plug-in connectors makes it a lot easier to use. While seting the machine up you will need to rewire often. Having to unscrew ~20 terminals isn't fun.

I must have missed this - where is ver 2.0?  I didn't see it in the Projects section or in the previous comments.  Or is ver 2.0 your own doing?


Thanks,
Shawn

 

[GreekPIC]

I've made some changes in the board, you'll find them on page 12

 

[Glass-Giant]

Ah, I see now. I must have missed that on my first run through.

 

[morir]

Hi.

I

 

[Dazza]

Oh, that's great GreekPIC Thanks ,

not only a nice snapshot of the good parts ;D, but some good construction tips as well .

Very much appreciated .

 

[Glass-Giant]

-It runs really cool. With printer steppers at 15V and heatsinks on the UCN's I had it running for 3,5 hours, moving the table diagonaly back and forth. Temp at the heatsink was ~30