4th axis on a excitech cnc

[mecanicu]

I'm starting a project for a rotary (4th axis) on a excitech machine...my big question is. It's possible to add the rotary on a excitech (shm2030a), dsp model (the controller only handles 3 axis... so i heared). The idea is to physical swap the wire from the X axis stepped motor with the wire from the 4th axis stepped motor ( it's important to say, the stepped motor that i use for the rotary will be the exact model whitch it's on the x axis). W8ing for idea's...Tx

[mecanicu]

no one know's..no one interested !!!!!HELP:d:d

[mecanicu]

I think i will be the first person "crazy" to do a 4th axis on a excitech cnc....

[mecanicu]

I need some advice on my project..the swaping of the x axis with the 4th axis i think will work....Kent_Norway for example it's the first who mannaged to do a rotary on a excitech cnc..buy his way was going from dsp to mach3...it's not an option for me...i am determin to make it happend on dsp setting's.."the swap project"...so all of you with some experience on electronic's and excitech cnc pls help me!!!!
it will be a new begining in excitech cnc's...

[mecanicu]

I did some reaserch and i found something interesting at the dps manual..i will add a pic so you cand understend "interpolation function: linear, circular".
How i cand change from linear to circular the x axis?????

[Big S]

I think you need a program called 'wrapper' or similar, then you change the X-axis over to the rotary axis and the software does the rest. I think the mechanical setup wont be too hard but the software side of things might take some sorting out.

Shannon.

[cabnet636]

sit tight fellowws soon there will be a software solution you will be happy with

jim

"http://www.youtube.com/watch?v=Q8QlyC9-oyA"]YouTube- grape column


"http://www.youtube.com/watch?v=uigIWptYOpQ&feature=related"]YouTube- grapes on a CAMaster

[Kent_Norway]

Hi there.

I have been in "CNC hibernation" but I would get back to your PM and posts when I finally have my version connected.

K

[Kent_Norway]

Sorry for late reply. Many projects going here now but tonight I managed to get the 4th axis connected. It was a mixed excitement and disappointment feeling in the "exercise" ...

Now for your questions :

1: If you have the stock DSP firmware you would need to work out the steps/unit for your 4th axis setup. So if you have made it using "something" with a reduction 1:50 or something - work it out and change it in your DSP just when you are doing 4th axis work.

2: Interpolation - Circular or not. I have no idea on what to do or implement in this respect

3: Homing sensor for the 4th axis; You could parallel connect this to your X or Y axis. This is how I have done it, but it does not work 100% ...

A summary of my experience regarding the 4th axis DSP firmware:

1: The firmware makes you able to change from XYZ mode and XAZ mode.
This means you cant move the Gantry while milling, the material milled must therefor be directed in X direction.

2: The manual says that you should connect the homing sensor from the 4th axis in parallel to the Y home sensor. This does not work for me. If you home the machine without the 4th axis connected, the machines homes OK. However if you have the 4th axis connected, power the machine on, hit HOME , the x axis is homed together with A and Z. Now changing to XYZ mode and homing the machine runs the Gantry to it's end stop and seriously damage the machine by knocking the Gantry to it's end position even if the home switches is passed. I thought this was caused by the fact that the 4th axis was in it's "home" position so I manually moved it out of position. This did not change the behavior of the machine ..
I have not checked which damage this action has caused on my machine, but both Y motors jumped heavily and I guess slipped on some kind of belt or something

3: The DSP is according to the manual suppose to have a 4th axis step/unit setting. I have still not found it any where in the setup so I'm not sure how the movement is linked to the physical movement.

4: My first comments on this firmware was not to good, but I think me and Tanney have talked passed each other here. Now if the firmware has a simple "step/unit" setting - I could live with the DSP as it is. I could accept to home the machine first without the 4th axis, then connect the 4th axis - home this and do my work. So if you read this Tanney, please let us know if there is a updated firmware we could use which includes the 4th axis "step/unit" setting - and in case - you possibly could sell this firmware for us which needs the 4th axis.

I have the USB CNC board lying but I have grown fund of this small little DSP unit and would hate to include a PC, new boards and tool sense setup.
If only this small function works I would be happy and I'm pretty sure that the manufacturer has a new firmware lying some where :-)

Hope it helped and again - sorry for my delayed reply.

Kent

[Big S]

2: The manual says that you should connect the homing sensor from the 4th axis in parallel to the Y home sensor. This does not work for me. If you home the machine without the 4th axis connected, the machines homes OK. However if you have the 4th axis connected, power the machine on, hit HOME , the x axis is homed together with A and Z. Now changing to XYZ mode and homing the machine runs the Gantry to it's end stop and seriously damage the machine by knocking the Gantry to it's end position even if the home switches is passed. I thought this was caused by the fact that the 4th axis was in it's "home" position so I manually moved it out of position. This did not change the behavior of the machine ..
I have not checked which damage this action has caused on my machine, but both Y motors jumped heavily and I guess slipped on some kind of belt or something

The Y motors jumping is the phases in the stepper motors being overridden. I have done this a few times on my machine when I accidentally bent a homing sensor tab out of place. I don't think the 'skipping' would do any damage to anything, I would be more worried about a high speed impact of the gantry onto the mechanical stops (been there done that too). At the speeds that the machine homes at, everything should be fine, YMMV.

Shannon.

[Kent_Norway]

The Y motors jumping is the phases in the stepper motors being overridden. I have done this a few times on my machine when I accidentally bent a homing sensor tab out of place. I don't think the 'skipping' would do any damage to anything, I would be more worried about a high speed impact of the gantry onto the mechanical stops (been there done that too). At the speeds that the machine homes at, everything should be fine, YMMV.

Shannon.

Thanks Shannon,

As usual you are a big contribution to the community :-)
My Gantry knocked in to the physical end stops during homing and I almost $hit my pants, seeing $ fly down the drain.... Good to hear that I'm not alone.

Long time since we spoke Shannon. Every things cool in your end ?

K

[mecanicu]

tx for your replay....i'm trying to contact someone from excitech for 7 day's now, so they cand enlited me....but no succes. i have another dilema....i studied my breakout board and i stumble on a interesting thing..."a c axis" slot. but my technical manual from the board it's in chine's, i need to know what that "c axis" is for. maybe i can connect the 4th axis there and only switch from x to a axis from the dsp....the firmware is the bigest problem for me now.....so if you can send my the firmware you have with the supossed 4th axis futures, i will be forever inded. tx.....