Light Engraving....

[sunil jain]

hi to every one...
Today I faced following problem with my GCC 25 watt-
First few lines are engraved dark and then suddenly engraving lightens.
optics are clean.
Any one help me on this problem.
regards.

[Viktor Voroncov]

1) Put picture of problem here
2) On which material you are engraving
3) Is this problem on different materials? Does it happened in the same place in file? on table?

[sunil jain]

1) Put picture of problem here
2) On which material you are engraving
3) Is this problem on different materials? Does it happened in the same place in file? on table?

Hi...Viktor...

1. i usually engrave on steam beech. the engraving with dark band and light band are marked.
2. the same problem is observed with acrylic and other material
3. the result varys day to day and moment to moment.
4. the engraving is darker at one moment, but at other moment engraving lightens suddenly.

regards

[Rodne Gold]

Looks like the tube is losing power - probably one of the 2 RF boards going bad , this will reduce power to 1/2 leading to the lighter engraving.
Does it get darker after going lighter or just start off dark and get lighter after a while?
Does the cutting also have issues?

I suggest opening your machine and cleaning all dust off both the laser source , fans etc and doing the same to the motherboard. A soft brush and canned air will work.

[Viktor Voroncov]

What is type of your laser tube and how long you work with this tube?

[Dee Gallo]

Have you checked whether your table is level? Could be bad focus too.

[Dan Hintz]

Try posting a pic that isn't so heavily degraded by JPEG compression... it's difficult to tell if you're getting no output on certain strips or if it's actually just a lighter engraving.

[JAIME PUJOL]

I had a similar problem lens went bad had to replace. You can tell with a eye loop if the lens has flak out.

[Viktor Voroncov]

If tube is Synrad 48 and worked at least 2 years - 99% problem in tube but easy to fix (30 minutes and $2)

[Rodne Gold]

Whats the fix Viktor?
Synrad sent me a circuit diagram of their RF board and the components needed to repair it , was quite cheap , but they also sent the instructions of how to tune the boards and that didnt look at all simple, you needed an occiliscope (sP?) and an offboard controller...

[Viktor Voroncov]

Usual problem of Synrad 48 is broken capacitors on boards inside tube. If tube is out of warranty, open it, check capacitors (marked RED CIRCLES on picture), buy from local electronic shop replacement and work.

[Rodne Gold]

Ta Viktor - looks like something else blew up on that tube judging by the scorch mark further down the cover ?

[Viktor Voroncov]

Yes, but it was another story Picture is just for demonstration when capacitors are.

[sunil jain]

Thanks for all of you.

1. Rodne Gold:-
it get darker few lines and lightens till last. machine cuts 3mm cast acrylic ay 2.8s/100p in enhance mode.
sometime it is light from starting and remains as it is till last point.

2. Dan Hintz:-
picture posted earlier may appear freaky because the engraved plaque is scanned.
I am again sending engraving sample 100p/12s. Earlier the same result was achieved at 100p/30s.

3. Dee Gallo:-
The level & focus of machine is perfect.

4. Viktor Voroncov:- "If tube is Synrad 48 and worked at least 2 years - 99% problem in tube but easy to fix (30 minutes and $2)"
My GCC 25W 3 year old and tube is synrad J48-2S-SGC. What is the way to fix the tube. Can it be done locally.

regards

[Rodne Gold]

I definately looks like either Viktors fix would work (worth a try) or one of the RF boards is going west. Typically , when one goes , the power drops to 1/2
Problem is , if it is a RF board and you continue to run it like that , both boards will fail.
Mail Synrad and ask em what can be wrong , they will send you repair instructions - the parts for the RF boards are cheap and can be found almost anywhere. As I said before , the tuning of the RF boards could be an issue , however I'm sure that there was a poster here that did repair their own and left em untuned and had no issues.
Call GCC as well , or mail em , they can offer you a refurbed swap out tube , you send em your old one and they send you a "new" one - its not cheap tho.