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Hi everyone,
I have a crazy idea, as strange as it might sound I am planning it for a while.
I purchased a 3060 40W Chinese machine a while ago, very dissapointed with the quality. The alignment is poor, it will never be on focus all over the table size and the table itself it can never be laveled.
I thought to take out the tube and power supply, make a decent housing and cooling system and attach it to an old CNC mill I have.
I use the laser mainly for cutting, I think using it on a perfectly aligned machine should give good results.
The question is, which parts of the existing optics I need.
I think of installing the tube vertically, so the mirrors are not needed.
I think there is a focusing lens which should be left in place.
Am I skipping anything? What problems should I expect?
Any comment or idea will be highly appreciated.
So the Laser tube will be on the Z axis up/down?
believe it or not but i went through this whole Forum for lasers as i am interested in buying or making my own.. and i did read some where that its a bad to put tube on an axis,,
Correct me if I'm wrong ..
I can't logically think what might be wrong:
A vertical milling machine moves the Z up down while the X/Y is table movement.
The Z is adjusted exactly as the table height is adjusted on the laser engraver. The nice part is that while on the laser the head moves X/Y and for this it needs the mirrors, here I don't need them.
No vibration will be transfered to the Z from the table, which is controlled by servo motors.
Another thing is the distance from the tube to surface, which with this setup is becoming the shortest possible - no mirror problems of any kind.
What I am not sure is if there is a lens on the laser's head or not and if there is how to align it.
I am just thinking of the possibilities and advantages this setup can provide, and the nice part is like an attachement to the CNC, I can cover it when not in use, I can use a far better cooling system (at least better than the aquarium pump provided by the Chinese factory) an my intention is to use it on an open frame CNC mill I have, which is used only for plastics.
The only thing I am not sure about is the lens.
You will need to keep the focusing lens. The laser light spot has fuzzy edges, and the lens makes the spot have a hard edge.
I would like to know more about this, and will be watching.
John
Your idea is not crazy, and I see no reason it would not work well.
The laser would only require the lens which could be mounted into your assembly.
I would only be concerned that to focus you will need to move the laser assembly up/down on the Z-axis. With servo drive this should not be a problem, just keep the accel/decel smooth and the speed low.
Install plexi/acrylic safety covers with interlocks and you should be fine.
Zax.
THE OPTICS IN THE LASER SYSTEM, INCLUDING THE MIRROR, ARE DESIGNED TO BRING THE BEAM IN FOCUS AT THE DESIGN CUTTING HEIGHT. YOU NEED TO KEEP THE LASER TO CUTTING HEIGHT WITHIN THE DESIGN PARAMETERS, SO, WITHOUT THE MIRROR, YOU NEED ADDITIONAL HEIGHT WHICH HAS TO BE PROVIDED IN THE Z AXIS. IF THE MIRROR IS NOT FLAT, IT IS PART OF THE FOCUSING OPTICS AND CAN NOT BE TAKEN OUT OF THE BEAM PATH.
THERE IS ALSO THE QUESTION OF COOLING, YOU HAVE TO MAKE SURE THE COOLANT FLOW WILL WORK VERTICALLY, THAT THERE WON'T BE TRAPPED AIR OR AREAS OF NO OR LOW FLOW ALLOWING LOCALIZED OVERHEATING WHICH COULD CAUSE DISTORTION OF THE OPTICAL PATH, LOSS OF FOCUS OR AIM, LASING EFFICIENCY OR PERMANENT DAMAGE.
hi, bro emvali.
can i know what brand ur machine?
and give more information about ur problem, my be i can help u.
because i laser engineer Han's Laser china brand!
I checked the spare set of mirrors I got with the machine, they all look flat.
The existing system has 4 mirrors: If I sum all the distances the beam travels from the tube end, the first mirror is placed at some 8cm away and shifts the beam up to the second mirror which is some 25cm away from the first one. Then a third mirror is installed on the X axis, at 0 it sits some 10cm away from the second mirror and at X=60, 70cm. The last mirror is installed on Y just above the lens, it's distance from the third is at 0 also some 10cm and at max Y 40cm.
So, the beam length is at 0 some 52cm and at XY max. 143 cm.
The distance between the last mirror and the focusing lens is 3cm and the focus is at 45mm.
The possible vertical setup is 30-40 cm above surface.
The mirrors are one big problem with all the Chinese engravers, as they all look flat I guess I need the focusing lens only.
About the cooling system, the first thought is to use the CNC machine's system, with the addition of a filter. On my laser tube the cooling entrance is near the positive voltage end and the exit near the beam exit. I think this will make things even easier.
What I am a little worried about is the coolant pressure, these laser tubes are very fragile, if you sneeze in the wrong direction they break.
My machine is a 3060 made by Artsign, very dissapointed with it.Originally Posted by arsuman
By the way, I am thinking if I make the setup using the CNC mill to use a 80 or 100W tube - I am using it mainly for cutting and not engraving.
I see the laser tubes at this power are very long, do you have any knowledge of shorter, more compact types?
Thanks
Hi, Emvali
Please keep informed about progress - idea is excellent
I am worry only about two things:
1) Cooling of laser tube - have no idea how will work vertical water flow.
2) Proper fixing of laser tube - you must have from smooth fixture from one side to keep glass tube, and rigid fixture to keep optic line always same.
But I see advantages:
1) No mirrors - no power decrease
2) Straight optic line
It is not necessary (contrary to Ken's shouting) to keep the distance from end of tube to the focus mirror the same. This can be reduced to your 30cm range without issue, the opposite (having a greater distance) would not be true.
The mirrors (yes, they are flat) serve no benefit, in fact they just incur losses in the system.
More power = longer tube. You could always use 2 x 40W tubes. It has been discussed here before.
Zax.
This is because of something called divergence. The laser beam widens as it propagates and the focus will inevitably shift if the lenses are fixed. Usually you want to focus the beam at the center of your work so then as the optics move back and forth the work will be more or less in focus.
Flying optics is best for speed and raster work benefits with speed. Try moving a XY table at those speeds.
I understand your frustration and to save you some more frustrations I would advise you to learn about your machine capabilities and work within them. That would give you best results.
The longer the tube - more co2 molecules are excited and lase = more power, the longer is the distance between the electrodes - higher voltage is needed to get it to lase.
Cheers.
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