GS15plus problem

[netsol]

Tbh you might be experiencing interference.. As it's a VERY old machine theres virtually a 100% chance that the electrolytic caps in the psu and other circuits have now started to fail - it's very common in vintage equipment - so you'll now be getting ripple in internal power lines which does affect the main board - also many newer machines (pc's, basically anything using power) use switched mode psus which can introduce noise into the mains input - a ferrite bead can reduce inbound noise, but replacing the caps isn't a particularly hard task, but there might be a "few".

if the problem wasn't so consistent, i would agree with you. but, the electrolytic only effects the middle circle? doubtful i would think.

but, you are on the right track. if i am playing with one of my gerber 4b's or an edge, i would blow everything out with compuressed air, unseat every plug in chip CAREFULLY and reset. unseat every plug at least twice (spray with non lubricating contact cleaner if you have any) buy a cheap ESR meter on ebay for $20 and check all electrolytics, resolder all heavy pin connections on the bottom of the board

this has fixed more gerber edges (trunnions, le's and edge 2's ) than i can count

 

[Sander_Sander]

Looks more like that while buffering something goes wrong and when the machine gets the next few instructions it goes wrong at that point. I will see when the next chips arrives if that solves the problem.
If these are replaced by new ones i can rule them all out.

The buffer chip also repaired the Gerber Fastrack twice. Fingers crossed....
I used compressed air also to clean it up inside.

I also ordered the caps for the pc that died last week, see if i can revive this one too. When i can afford to do the upgrade for the software and the usb to edge cable i can work from my new pc, and the old pc can be put in storage.

 

[netsol]

Looks more like that while buffering something goes wrong and when the machine gets the next few instructions it goes wrong at that point. I will see when the next chips arrives if that solves the problem.
If these are replaced by new ones i can rule them all out.

The buffer chip also repaired the Gerber Fastrack twice. Fingers crossed....
I used compressed air also to clean it up inside.

I also ordered the caps for the pc that died last week, see if i can revive this one too. When i can afford to do the upgrade for the software and the usb to edge cable i can work from my new pc, and the old pc can be put in storage.

yes, unfortunately, the chinese learned out to use the cheapest electrolyics
we started having this issue with televisions, vcr's and camcorders in the late 1980's (this all came with miniturization and surface mount components. they eliminated any safety factor (25 V cap in a 16 volt circuit. that sort of thing)

 

[Sander_Sander]

yes nowadays there is a lot of crap for sale unfortunately, i rather have one of these old reliable work horses than a new one.

 

[netsol]

i am a computer consultant (semi-retired(?)
i am going over about 25 older computers still in use at a united way office this morning
you don't have to tell me about older computers and devices still in use

 

[Vassago]

Hi Vassago, thank you for your answer. I have ordered all the push in chips that i could find at the webshop that sold the buffer chip, those will all arrive next week. If this does not fix it i will look at the caps, i have replaced a cap on a monitor that stopped working, i can do that.
Where should the ferrite bead be placed? On the Com port cable?

On comport & mains cable.. The older things get, the more susceptible they become to transmitted noise.. The big smoothing caps are one of the main issues - the esr will rise dramatically with age.. Most electrolytic caps last 10 - 15 years.. Once you go beyond that it's a downward spiral - the hotter things are the quicker they degrade.

You've got to remember.. A gerber of that vintage is a very very simple beast. Psu + step direction drives and a simple controller. Not much to go wrong, but if you get interference it can mess with the main board and thus the step/direction drives.

 

[Sander_Sander]

thank you Vassago, i will first see what happens when i replace the chips. If that does not solve it i will replace all the caps.

 

[kritze66]

While waiting on the above parts, you might check the timing belt to see if it's missing any teeth. I have a couple GS750s machines and this problem has occurred before. Maybe only one or two teeth are missing? Hope this helps.

 

[Sander_Sander]

Hi kritze66, thank you for your reply. My machine has the swivel knife option, that orange belt is not used when using this. My belt is detoriated, and i have locked the head in place, have not needed the normal function in years. I only use the swivel knife because it is way faster than the tangential function.

 

[netsol]

He raises an interesting point. are teeth missing on either of the other belts?

 

[Sander_Sander]

I will have to check that....

 

[Jburns]

are the chrome rails very clean? I have heard of this when rails are dirty, unoiled .

 

[FunkotronXL]

Had a GS15+ years ago that did this exact same issue. Never got it resolved and parted out the unit after too many repair events and shipping costs.

When the plotter does this, I'm guessing you hear that "buzz/chirp" noise as, what looks like your Y-axis from the image, slips and loses position on the web. Best guess was the issue was mechanical. Gear mesh, belt wear, loss of Y-axis motor torque are potential places to check.

When the issue starts, does it repeat for every plot? or does it flip back and forth between proper plots with occasional slip fails?

 

[Vassago]

Another possibility is increased friction or reduced stepper power - could result in lost steps..

 

[Sander_Sander]

Jburns: Yes rails is clean, i once had the rails a bit dirty after not using the machine for a while, but then it makes more like an egg shape when you cut a circle then a complete sudden 90 degree turn while cutting, that is not what is causing this problem

@Funkotron: it suddenly changes direction and instead of cutting a round shape it makes a line in the length of the machine (guess that is X axis, the way the roll goes through the machine.
The problem does not always occur, sometimes it does and sometimes not. I used it today to cut out some other things (some small stickers, with all kind of shapes), and this went perfect. I also have made a sticker that is like 50x65 mm, and has around 330 rectangle shaped holes in it with tiny rounded edges, cut 3 of those above each other and all went perfect. In total that was 1100 somewhat objects to cut.

@ Vassago, is it possible to check a stepper if it gets enough power?

Today i got the chips, will install them tomorrow and see what happens then, my large cutter was fixed twice by renewing the Buffer chip.

 

[Sander_Sander]

I have changed the Buffer chip, but the error still occurs. I will change the other chips that i have got too. When after that it still occurs i will proceed to renew the powercaps.

 

[jfiscus]

Just judging based on all the comments here and the photos I can see, it looks like it is only taking a crap on the one axis.
It looks like it is trying to complete the shape on the X axis (linear through the machine) but it looks like it is in the wrong position across the machine.
I'd look into trying a different motor for that Y(?) axis, we had ours crap out a couple years ago. Definitely look in that area, maybe even a cracked gear.

I've used these machines for quite a long time and never had to do electrical stuff like capacitors, but I've replaced many motors, sensors, and gears.

 

[Sander_Sander]

jfiscus thank you for your reply, i took the covers off again, i checked all the belts and gear teath, these are ok. Is there a way to check the stepper motor or is it only possible to swap it out for a new one? I have no clue of how to check its function.
Is a cracked gear on the inside of the stepper motor? Or do you mean all the gears where the belts are running around?
The part number on the motors are M061-LS-541 (for turning the roll through) and M061-LS-518 (for moving the head) and are from Warner Electric, it says SLO-SYN MOTOR. I am looking to find a replacement motor now. I am not sure if it is the one that moves the head or spools the roll through the machine.

 

[James Burke]

I've been away from my desk for a few weeks and am just seeing this. But from my experience with a IVB connected to an LMK, I'd guess the problem is somehow due to data over-flow. I can't remember exactly what I did to finally solve the problem, but I seem to remember it had to do with slowing down the baud rate and utilizing a serial card in the PC, instead of a USB adapter. Once I got it fixed, it never gave me a moment's problem....ever.

But my results were just like yours....it always gave very consistent and predictable results, and you could literally bet Vegas (and win) at just when and where it was going to fail.


JB

 

[Sander_Sander]

i have contacted a company that is specialized in these motors to see if they can be refurbished or that they can supply me with new motors.