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Palmar
29-10-2015, 05:47 PM
Hi!!

MY first post. For many years I have been thinking of buying an CO2 Laser Cutter. The ready to use chineese cutters range from 900-3000gbp
have been looking for an 5030 or 6040 machine. But have been reading alot they are unstable and no support after ordereing from China. Even they promise good service and support.
So I will not go that route.

So I was thinking, maby I could build a CO2 laser instead, with quality parts ang get a more stable and better laser cutter.
Will use the CO2 for cutting up to 4-5 mm of plywood and 4-5mm of acrylic sheets. Also do engraving into theese.

Maby one of theese rails will do the trick? :
http://www.aliexpress.com/store/product/High-Quality-motorized-customized-length-Linear-rail-laser-cutting-laser-engraving-parts/1264013_32244576102.html
or http://www.aliexpress.com/store/product/cnc-linear-motion-guide-hgh25ha-linear-guid-high-speed-linear-guides/617865_2037540272.html
i just need a 6040 system complete with head. Price is around 700-800gbp for the kit

need to add:
motors + driver
lasertube 50 or 60w + psu
optics
dsp system awc 708 lite
wires
any thing else ?
And build and case around the whole machine

My question is, what is the recommended of
Servo or stepper based motor?
lasertube + psu ?


Thanks for all reply :D

Regards
Palmar

Robin Hewitt
29-10-2015, 10:41 PM
If you are cutting plywood you need to pump air down with the beam so the tarry gungy horrible smoke cannot get back on to your lens rendering it opaque and destroying the surface coating.
The 6040 I got had a particularly naff fume extraction, a vague suck somewhere at the back, sudden steps in the ducting, no particular air inlet to guide or encourage the flow.
The driver board and ghastly dongled Chinese software, open frame high voltage PSU scarcely justified the enormous amount of case set aside for them. Every expense had been spared.
What it really needed was a water flow/temperature measure to stop me firing up the tube should the flow stop for any reason.
If making your own, remember that everything below the beam wants to scatter light, not reflect :calm:

Palmar
30-10-2015, 08:28 AM
If you are cutting plywood you need to pump air down with the beam so the tarry gungy horrible smoke cannot get back on to your lens rendering it opaque and destroying the surface coating.
The 6040 I got had a particularly naff fume extraction, a vague suck somewhere at the back, sudden steps in the ducting, no particular air inlet to guide or encourage the flow.
The driver board and ghastly dongled Chinese software, open frame high voltage PSU scarcely justified the enormous amount of case set aside for them. Every expense had been spared.
What it really needed was a water flow/temperature measure to stop me firing up the tube should the flow stop for any reason.
If making your own, remember that everything below the beam wants to scatter light, not reflect :calm:


Thanks for the reply.
I will add a waterpump and a exhaust system + an air compressor for the head.
I think a knife or honeycomb table will do the trick for no reflection of laser

Palmar
30-10-2015, 12:43 PM
Nema 23 motor with 8mm shaft... but there are many of theese, different types... any that is recomennded for usage with a co2 laser and drivers
Is it best to use dual shaft motor in Y axis?

Will this do:
Nema 23 motor for y axis


Step angle: 0.9 deg
Step per revolution: 400
Phases: 2
No. wires: 4
Current: 2.1A
Holding Torque: 0.9 N.M (127 oz*in)
Dual Shaft: 6.35mm in diameter
Dual Shaft length: 21mm
Inductance: 2.5 mH
Phase resistance: 1.8 ohms
Detente torque: 400 gcm
Rotor Inertia: 280 g-cm2
Weight: 0.6KG (1.4lb)
Length: 54mm

Robin Hewitt
30-10-2015, 11:09 PM
The 6040 uses 200 step NEMA17 motors which are really zippy at 12V.
There are no cutting forces, you really want to keep this as light as possible, especially if you want to scan a cross hatch engraving.

Palmar
31-10-2015, 12:09 PM
The 6040 uses 200 step NEMA17 motors which are really zippy at 12V.
There are no cutting forces, you really want to keep this as light as possible, especially if you want to scan a cross hatch engraving.

I see. What about the step angle?
I see there are 0.9, 1.2 and 1.8 angle.
Should I go for an nema 17 also for the x axis ?

regards

Robin Hewitt
31-10-2015, 09:29 PM
Sorry cross purposes, I am trying to do too much and, apparently, failing miserably :confusion:

I am talking about the cheap Chinese laser, you are talking about converting a cheap Chinese router table in to a laser :frog:

Please ignore everything I said :hysterical:

Palmar
31-10-2015, 11:04 PM
hehe
I have ordered the rail kit from mjunit Link here (http://www.aliexpress.com/store/group/Laser-machine-Linear-rail/617865_253373815.html) want to build co2 laser cutter/engraver from scratch :) I think that is better than ordering theese systems.
Regarding the motors and drivers, I am a bit confused... There are a sh*tload of different nema 17 and nema 23 motors.
They recommend nema23 motors since they have 8mm shaft. And the kit contains 8mm couplings and mounts for nema 23. But I am lost here...so many motors to choose from.

What do I need to look after regarding motors and drivers?

Palmar
04-11-2015, 10:35 PM
I would be gratefull for any tips regarding motor + driver :D

Palmar
10-11-2015, 04:53 PM
Just received the parcels today. Well packed.
1650316504

Here is layout
16505

Will build a frame of aluminum extrusions 2020 and 2040.

More later..

PS.
Any tips regarding motors + drivers? ;) It has 57mm mounts.

Palmar
13-11-2015, 09:30 AM
Wrong motors...