Messages

151

Competitions / Re: ******Guess and win a G100 Grex******

« on: May 22, 2007, 01:16:24 PM »

My Guess is 2,473,682 chips 

152

General Mach Discussion / Re: Denford ORAC.

« on: March 03, 2007, 09:35:21 AM »

Hi, As asked here is the circuit diagram and the current macro I'm using.


Hope this helps.


Regards
John

153

Tangent Corner / Re: Stand alone indexer

« on: January 16, 2007, 03:41:02 PM »

Hi, ahh Step quantity. Perhaps I didnt read your last post correctly. It can be done but if your like me having time to build circuits and printed boards it's just as easy to buy something ready made. I looked at the cubloc website and they have got things well sorted. Probably the best route to go.


Regards

154

Tangent Corner / Re: Stand alone indexer

« on: January 16, 2007, 08:25:27 AM »

Hi, If you are into electronics, You could use a 555 timer for the pulses and an L298 bridge driver to handle the stepper. With clever use of another 555 tied to the first's control pin 5 you could ramp up the pulses. It would be cheap and simple circuit on vero board.


Just a suggestion.

Cheers

155

Feature Requests / Re: Turn Graphics Stock Control

« on: January 07, 2007, 03:05:29 PM »

Hi, I did mention this in another post quite a while ago, It is the only thing that lets Mach-Turn down as a design-it, see-it, cut-it, program.

I hope that something could be done to change that, meanwhile I'm still using the old Boxford DOS software to design the g-code as it has an 'accurate'? view of what the end product will look like.

156

Others / Orac Toolchanger Circuit Diagram

« on: January 06, 2007, 02:31:10 PM »

The toolchanger circuit diagram for the Denford Orac showing the wire colours used. The supply is 12v and the motor supply is 24v.

157

General Mach Discussion / Re: Help! Please! this Chaos has to stop!

« on: December 06, 2006, 06:32:13 AM »

Hi, The video say's it all. The sound is the stepper not keeping up with the amount of steps being sent from Mach. If you go to Motor tuning and select the drive, Let's say Z and decrease the Accel value then click on save settings. This will allow the pulses to ramp up from a slow start to the feed rate you set.

I did notice that during the quick ramp up to speed there is a low resonance vibration that occurred before losing steps. If you have the driver with microstepping there is a small adjustment screw on the back of the Gecko driver

ADJUST: This trimpot adjusts the motor for the smoothest possible low-speed operation. Set the motor speed to
about 1/4 revolution per second, then turn the trimpot until a distinct null is noted in the motor’s vibration. This will
result in the most even microstep placement for a given motor and power supply voltage.

Failing all the above, Your power supply Voltage is too low for your needs. I would suggest upgrading the power supply to a higher Voltage.

If you eventually decide to do this we are all here to help.


Kind Regards
John

158

General Mach Discussion / Re: Help! Please! this Chaos has to stop!

« on: December 06, 2006, 06:29:09 AM »

Hi, The video say's it all. The sound is the stepper not keeping up with the amount of steps being sent from Mach. If you go to Motor tuning and select the drive, Let's say Z and decrease the Accel value then click on save settings. This will allow the pulses to ramp up from a slow start to the feed rate you set.

I did notice that during the quick ramp up to speed there is a low resonance vibration that occurred before losing steps. If you have the driver with microstepping there is a small adjustment screw on the back of the Gecko driver

ADJUST: This trimpot adjusts the motor for the smoothest possible low-speed operation. Set the motor speed to
about 1/4 revolution per second, then turn the trimpot until a distinct null is noted in the motor’s vibration. This will
result in the most even microstep placement for a given motor and power supply voltage.

Failing all the above, Your power supply Voltage is too low for your needs. I would suggest upgrading the power supply to a higher Voltage.

If you eventually decide to do this we are all here to help.


Kind Regards
John

159

General Mach Discussion / Re: Help! Please! this Chaos has to stop!

« on: December 05, 2006, 06:35:42 PM »

Hi, The numbers on Mach will still run because you don't have a closed loop system and Mach doesn't know there is a problem. Lets assume that the pulses coming from Mach are reaching the drivers OK. If you could test for this it would eliminate one possibility.

I believe your problem could be one of these things...

1) If all the drivers have a common enable signal (terminal 7 on Gecko's) then an intermittant on/off signal on this will mess things up as you have described.

2) The power supply to the gecko's could have a fault, a dodgy wire or perhaps the rectifier is on the verge of failing.
I have never had one with an intermittant fault. they usually fail totally but you said the box got very hot and this is one of the components that would get hot (maybe the case it is mounted on is not dissipating the heat.

With this in mind could you substitute the power supply, like using a 24v battery charger or batteries  just to test.

Look forward to the video.

Kind Regards
John

160

General Mach Discussion / Re: Help! Please! this Chaos has to stop!

« on: December 05, 2006, 12:39:00 PM »

Hi,  Hood is right. Although a power supply of 75v would be better, It seems by your explanation in the email this will not sort your problem immediately. You said that when the axis miss steps the steppers moan.

Are you saying that when the problem occurs, all the axises stop at the same time (for how long) and then start working again normally? This is the big question because if that is so we can eliminate some of the things it might be.

Your port and baud settings are OK. As are the current resistors. The mounting of the Gecko units should be OK for steppers under 3amps although heat transfer paste between the Gecko unit and the mounting would be better in the long term if you are using the machine all day every day. But don't worry about this for now.

Shielded cable has the earth/ground wire on the outside of all the other wires made like a lattice (similar to TV aerial cable or audio cable)
It acts like a Faraday cage and keeps stray signals from getting in or out of the cable long it's length. All of your signal wires should be shielded ( wires to the computer and the step and direction on the gecko's)

I hope I've answered most of you questions but to get back to the problem I need a better explanation of this moan from the steppers or perhaps a video of this problem happening.

Does the moan sound like a low vigorous hum?

Regards
John