Laser sporadic engraving

[Mike]

Its me again

photo below shows my issue, just started yesterday, when engraving it seems to miss out lines, not always the same thickness and not always in the same position,
its sporadic which makes it really hard to fault find.

I am thinking its maybe a poor connection on the tube, just wondering if anyone has had this before?

http://i171.photobucket.com/albums/u292 ... defect.jpg

[Spooky]

Hiya Mike,

Poor tube connection or "bleed" of the inbound power will cause this, have a look at your clips where the tube is joined or if you have soldered joints than maybe the croc clip modification is in order?

Check to ensure your wires aren't near or touching the metalwork of the machine to start with though.

Have you tried with different drawings as well?

Is the error consistent ?

best wishes

Dave

[johnb80]

Its me again

photo below shows my issue, just started yesterday, when engraving it seems to miss out lines, not always the same thickness and not always in the same position,
its sporadic which makes it really hard to fault find.

I am thinking its maybe a poor connection on the tube, just wondering if anyone has had this before?

http://i171.photobucket.com/albums/u292 ... defect.jpg

If you engrave again is it exactly the same or does the missed bits move?

J

[Mike]

Its never the same place, I need to try a more simple shape in different sizes.

the tube I have has soldered connections on it, what does the plug look like, As I may try and get some of those instead?

[Spooky]

Just a simple croc clip Mike,

That's all that is on mine.

best wishes

Dave

[bob]

Hi What speed and power are you using and on which machine?
high speed can sometimes cause them to jump

[Mike]

Heres an update.

I came to use the machine again and found that the laser wasn’t firing at all… gutted!

So I redid all the laser tube connections, tried the croc clips too, still the laser did not fire.

So I replaced the laser tube with a brand new one, Still the laser tube did not fire… more gutted-ness

So I had to look elsewhere, I know the machines are fitted with at least two safety mechanisms that prevent the laser firing,
The top door sensor and the water flow sensor. It turns out the electrical connection on the water flow sensor was intermittent.
The sensor and hose are suspended at the rear wall of the machine the only thing holding them up is the wiring into the sensor,
If and when I get a new flow sensor I will cable tie that direct to the rear wall.
I bet these are not off the shelf parts!

Hopefully this will solve the intermittent engraving issue too

I really do wish there was better information about the electronics and logic control in these units, it would have saved me allot of stress.

[Mike]

Also just to add the croc clips did not work well on mine, Dave have you got a big sleeve to insulate the clips. I had some arcing so went back to the solder method with lots of insulation.

[Spooky]

Hiya Mike,

Silicon tubing over the entire clip works, I'll take a photo of mine and post it so it's a little clearer.

The 22Kva will jump 4" unshielded.

best wishes

Dave

ps: Back in 5

[Mike]

Mine was arcing about 1", when I managed to get the laser to fire.
I have that old burnt out tube that I could steel the silicon tubing off

the cathode side didnt arc, so I take it that is connected direct to ground?