Replacing Epilog Helix Laser with Chinese or other less expensive laser

[Colby Boles]

I'm missing why you would need to replace anything but the laser, power supply, and laser control interfacing? Why would I need to change the stepper motors or other aspects of the table drive system?

It is *possible* to interface a glass tube , you need a tube and power supply , a motherboard and lcd panel. Possibly new stepper motors and stepper motor drives. Will cost about $1000-2000
It wont be easy tho. You will have to most likely rewire and do extensive fabrication on the machine. Basically the software and hardware (non epilog , would be something like RDCAM + RDLC320 motherboard) will control the stepper motors , steps per inch when the machine fires , acceleration rates , what the machine limits are etc etc etc
All in could cost you close to or more than $4-5k in time , aggravation etc. You would still have a compromised "unsaleable" machine.
I think it would be better to get a RF tube for $6.5k or import a fully running 1200 x 900 80w machine from china for that money.

[Richard Rumancik]

I'm not sure what you mean by the "Laser control interfacing" but to me that would be the mainboard. I don't know your system but I think that you have a separate motor controller (drive) on that machine. (On some laser systems the stepper or servo drives are on the mainboard.) So supposing that you do have a stepper controller board and you replace the mainboard with a Chinese unit. How will you interface the Chinese mainboard with the Epilog motor controller? More than likely the protocol between the mainboard and controller is proprietary and you will never be able to reverse-engineer it. And even if you could it would not be cost effective.

On some CNC routers and mills there is a lot more modularity between each part of the system and the signals/protocol between modules are more standardized (such as step/direction signals, G-code). But I don't think you will see any standardization on laser systems. If you can't get the Chinese mainboard to talk to the Epilog motor control board (I'm assuming it is separate) then you would need new motor drives. And with new drives chances are the existing motors will be incompatible. Hence Rodne's comment . . . .

[Rodne Gold]

As Richard says , stepper motor drivers are not on the chinese motherboards , so if they on the epilog Mobo or it has another motor driver board , you will probably need to replace em. More difficult will be to change the wiring to the new motherboard as it does not accept stuff like ribbon cables and any other proprietory connector. It might need wiring extensions and a lot of tracing or replacing.
You would maybe have to replace limit switches as well , you might have to replace the power supply to the mainboard too. You would almost definitely have to cut or weld a platform on your machine to accept the tube , possibly leaving the tube hanging out somewhere (with the HT end exposed). In all probability you would have to change your 1st mirror mount and possibly amend all of them.
You will need a chiller like a CW 5000 ($450) or maybe something lesser if you got a lower than 80w tube. You will have other issues , like glass tubes cannot fire at low powers , which might limit you in what you want to process. The one good thing is that a motherboard like a RDLC320 and the software like laserworks/rdcam is extremely configurable and can actually be set up so that the conversion WILL work..however this is like re inventing the wheel , kinda like building a laser from scratch. You will have a Chevy with a toyota engine , mopar gearbox and foird wheels and brakes.. Would you buy such a vehicle or would you feel confident in it's reliability or high performance?

If you don't want to spend $6.5k , then sell your laser on for $3k and add in another $3k to get a chinese one ( The ones I got for under $6k work extremely well , I have mix of "mainstream" and chinese machines )
Up to you , if it was me however , and this was my first laser , I would spring for the epilog tube and enjoy better software , a faster laser, retain inherent value and use and local support...

[Colby Boles]

I do reverse-engineer hardware / firmware for a living, and bought all of the CNC equipment in our shop (waterjet, VMC, CNC press brake, etc.) in non-working condition and got them up and going, but I think that might be beside the point here. Like most machines, I would think all laser cutters basically consists of a mainboard that is controlling the motion system as well as the laser output. To me the laser module itself is fairly self contained with a power input and some analog or digital control signals to control the turn on, pulsing and output power as well as any error or trouble states of the laser. I would think that all laser supplies have somewhat analogous control inputs and outputs. I would think the main challenge would be if the replacement laser had different latency characteristics that couldn't be dialed out in the user accessible portion of the software before the motion path and laser power timing sequence was computed that is executed by the mainboard.

For reference, here are a couple of drawings for a 70W Coherent laser that I think is pretty similar to the 75W one that goes in the Epilog:

http://www.coherent.com/downloads/Di...evB_0812_3.pdf

In the rear view drawing you can see it has the same RJ-45 control connector and 48V power supply that my unit has.

Looking further into the Coherent Integrator's manual on page 37 you can see the pinout of the RJ-45:

http://www.coherent.com/downloads/Di...AA.pdf#page=42

Coherent RJ-45 pinout.JPG

So it looks like there aren't any analog controls at all - just a TTL input to enable the laser, another to pulse / control the RF, and 4 TTL status outputs.

I don't know how much a C70A costs, but it might be the easiest replacement after getting one from Epilog.

[Colby Boles]

I hear your point on the Chinese laser tubes being on the long side - I really do want a solution that fits inside the unit (other than a chiller if needed). I'm still not following why a laser change would require a new mainboard / motion control system. Presuming you can get the laser to modulate its output in the same way from the same control inputs, I would think another laser would functionally be a direct replacement? Or is it that all of the lasers behave so differently in terms out output linearity and latency that the path / power pre-computations made by the mainboard will never be right with a different laser?

As Richard says , stepper motor drivers are not on the chinese motherboards , so if they on the epilog Mobo or it has another motor driver board , you will probably need to replace em. More difficult will be to change the wiring to the new motherboard as it does not accept stuff like ribbon cables and any other proprietory connector. It might need wiring extensions and a lot of tracing or replacing.
You would maybe have to replace limit switches as well , you might have to replace the power supply to the mainboard too. You would almost definitely have to cut or weld a platform on your machine to accept the tube , possibly leaving the tube hanging out somewhere (with the HT end exposed). In all probability you would have to change your 1st mirror mount and possibly amend all of them.
You will need a chiller like a CW 5000 ($450) or maybe something lesser if you got a lower than 80w tube. You will have other issues , like glass tubes cannot fire at low powers , which might limit you in what you want to process. The one good thing is that a motherboard like a RDLC320 and the software like laserworks/rdcam is extremely configurable and can actually be set up so that the conversion WILL work..however this is like re inventing the wheel , kinda like building a laser from scratch. You will have a Chevy with a toyota engine , mopar gearbox and foird wheels and brakes.. Would you buy such a vehicle or would you feel confident in it's reliability or high performance?

If you don't want to spend $6.5k , then sell your laser on for $3k and add in another $3k to get a chinese one ( The ones I got for under $6k work extremely well , I have mix of "mainstream" and chinese machines )
Up to you , if it was me however , and this was my first laser , I would spring for the epilog tube and enjoy better software , a faster laser, retain inherent value and use and local support...

[Rodne Gold]

There is not an issue triggering the laser to fire , the issue *is* when it will fire , latency , adjusting power etc as well as interfacing it's drivers
Whether you actually will have access to the epilogs MOBO or programming code to modify the system is debatable .. I'm pretty sure they wont be amenable to giving you that..but you can try.... It would be easier to use a MOBO designed for task... A RDLC320 + LCD screen + software = $400

GCC supply a glass tubed laser that uses more or less the same platform as its RF one , so it is a possible solution. The chinese glass machines are also configurable to use an RF tube too.
As an academic exercise , doing the retrofit would be interesting... as a commercial decision for a business ..I'm not so sure it makes economic sense.

[Mark Ross]

The other thing you might want to check out is if anyone on this forum or otherwise had that model and it caught fire. I don't know that model, but on Epilog 36EXT's the fire would have to be really bad to get to the tube section, most of the time the damage is up top.

[Colby Boles]

I hear you. We will not be using this laser for much production work so we are a little more willing to play around with it. I pulled the mainboard last night and also examined some of the firmware that runs it in IDA. It is an Intel XScale (ARM) PXA255 running vxWorks. I don't know how much is taken care of by their two FPGAs yet (at least one seems to be purposed towards the Ethernet interface), but it certainly possible what I am looking for is in there.

The more I think about it though, this Helix model comes with a variety of different wattage and model lasers in it. There must be at least some minimal configuration to let it know what laser you have, or compensate for eventual decline in laser power. At this point I don't know if the path and laser modulation is completely pre-computed on the PC side as part of the "print driver", or if the mainboard does some of the itself.

There is not an issue triggering the laser to fire , the issue *is* when it will fire , latency , adjusting power etc as well as interfacing it's drivers
Whether you actually will have access to the epilogs MOBO or programming code to modify the system is debatable .. I'm pretty sure they wont be amenable to giving you that..but you can try.... It would be easier to use a MOBO designed for task... A RDLC320 + LCD screen + software = $400

GCC supply a glass tubed laser that uses more or less the same platform as its RF one , so it is a possible solution. The chinese glass machines are also configurable to use an RF tube too.
As an academic exercise , doing the retrofit would be interesting... as a commercial decision for a business ..I'm not so sure it makes economic sense.

[matthew knott]

I think it could be done IF you can find a way to get into the epilog firmware and adjust the laser settings, we have a (broken) Epilog EXT36 that has a refurbished Coherent C70A laser in it, its in bits right now and i'm way to busy to put it back together right now. I have a fair bit of experience interfacing both Coherent and Synrad laser tubes and they are very simple in operation, as are the chinese glass tubes. The problem as already pointed out is RF tubes switch on/off times are much quicker, i suspect for slow vector cutting it may not be a big issue but for engraving you would need to find a way to synchronize the laser firing to the motion, it would be quite easy to go the other way and use an RF laser on a chinese system as they allow you access to adjust the settings but epilog don't You never know it might not be that bad and you might get lucky but you would have to do quite a bit of work getting the mechanics right to get the beam aligned with current optical system. I really don't think changing the motor and mainboard is a viable option, just buy a chinese laser and save the heart ache. You can find replacement RF lasers, we got a cheap coherent 30w of ebay 5 years ago and its still running like new in one of our galvo systems, but new they are very very expensive. Be interested to know how you get on with this project, when you brought it did you know the tube was missing? this is the sort of thing that ends up on ebay sold as 'working when taken out of action, stored for a while we know nothing about it, can't test it, sold as seen' and some sucker takes a punt on it thinking they might get lucky and net a bargain.

[Colby Boles]

Thanks for the reply. To be very clear to everyone, the sellers are in the govt. surplus business and were very upfront about the lack of laser and gave me plenty of details about why these end up with the lasers removed. The have a number of these machines to sell off one at a time to maximize their money - they list them serially on ebay, here is one for sale now: http://www.ebay.com/itm/Epilog-Helix...item53f7c78967

I'm not that familiar with the Epilog drivers yet, but I got the impression from a friend yesterday that works with a number of Epilog machines that the machines themselves are pretty dumb and so it would seem that all of the "CAM" path determination and laser timing is probably pre-baked by the print driver into the datastream that spools to the printer which is simply a motion control playback system with a buffer. I should be able to fake out some of the laser status signals on the CAT-5 cable and get this thing fired up sans-laser so I can start playing with the software and look at the datastream coming over ethernet or USB.

That said, I'm starting to get the impression that some sort of Coherent / Synrad / other RF tube will still be the way to go in terms of being able to fit it all into the same machine envelope. I might look into getting a C70L instead of the C70A and put a chiller underneath the machine. My prices from Epilog actually need correcting - it is worse than I thought before:

75w $12495.00/1 year warranty/Coherent Manufactured Tube
60w $7995.00/2 year warranty/Epilog Tube
50w $6495.00/2 year warranty/Epilog Tube
40w $4995.00/2 year warranty/Epilog Tube
30w $3495.00/2 year warranty/Epilog Tube

Where did you source the C70A? From Coherent?

Colby

I think it could be done IF you can find a way to get into the epilog firmware and adjust the laser settings, we have a (broken) Epilog EXT36 that has a refurbished Coherent C70A laser in it, its in bits right now and i'm way to busy to put it back together right now. I have a fair bit of experience interfacing both Coherent and Synrad laser tubes and they are very simple in operation, as are the chinese glass tubes. The problem as already pointed out is RF tubes switch on/off times are much quicker, i suspect for slow vector cutting it may not be a big issue but for engraving you would need to find a way to synchronize the laser firing to the motion, it would be quite easy to go the other way and use an RF laser on a chinese system as they allow you access to adjust the settings but epilog don't You never know it might not be that bad and you might get lucky but you would have to do quite a bit of work getting the mechanics right to get the beam aligned with current optical system. I really don't think changing the motor and mainboard is a viable option, just buy a chinese laser and save the heart ache. You can find replacement RF lasers, we got a cheap coherent 30w of ebay 5 years ago and its still running like new in one of our galvo systems, but new they are very very expensive. Be interested to know how you get on with this project, when you brought it did you know the tube was missing? this is the sort of thing that ends up on ebay sold as 'working when taken out of action, stored for a while we know nothing about it, can't test it, sold as seen' and some sucker takes a punt on it thinking they might get lucky and net a bargain.

[Richard Rumancik]

Colby - Putting in a Coherent tube gives you a fighting chance to get this machine back to life as that it what Epilog used. Anything else and you will end up needing a firmware patch and Epilog isn't going to release the code to you. If you use another Coherent tube why do you have to reverse engineer the machine at all? It would be a shame to spend a lot of hours on it and get it to "almost" work. Epilog might be willing to provide some assistance if you use a Coherent tube but not a Synrad or anything else.

Seems like you should just make Matthew an offer on his C70A tube, pay the hit on shipping over the pond, and you are all set.

[Stan Lightner]

One of the reasons I decided to join this forum was the rule of no politics. However, here I find several government bashing posts that have not been addressed by the moderator. Is this just another case of having a rule but not enforcing it when wing nuts submit their negative comments?

[Rodne Gold]

I am a moderator here and didn't see anything particularily disturbingly political in any of the posts , but I live in South Africa so maybe aren't as sensitive to this .. I always thought the USA was a bastion of free speech? Mike Null , who is a USA citizen is also a moderator and I see he has taken no action..
I think however you are out of order referring to posters as "wing nuts".

[Colby Boles]

I apologize - I'd assumed that the unnecessary destruction of perfectly functional lasers would be universally considered as wasteful. I'm not try to make any political statement here one way or another.

One of the reasons I decided to join this forum was the rule of no politics. However, here I find several government bashing posts that have not been addressed by the moderator. Is this just another case of having a rule but not enforcing it when wing nuts submit their negative comments?

[Stan Lightner]

I apologize - I'd assumed that the unnecessary destruction of perfectly functional lasers would be universally considered as wasteful. I'm not try to make any political statement here one way or another.

Neither you or I know the rationale behind the removal of the laser. To assume it was done due to some arbitrary governmental rule/policy is without merit.

Bottom line I'm a disabled Vietnam Vet who is more than a little tired of anyone who simply bashes the "guvermunt" since it is a easy target. I was also a citizen of Oklahoma City on April 19, 1995 so you may also have some sort of idea as to how I feel about off the wall negative comments. That said, I'll have to think a long time to decide if I will return to this forum, and right now its quite doubtful.