[SimonArthur]

I just bought an ArtCut M40 Laser (similar to the Rabbit HX40) from a reseller in the US. I'm trying to get it set up and am having a hard time aligning the mirrors.

I can get the laser to hit the center of the first mirror. I can even get the laser to hit the center of the second mirror when the carriage is all the way to the rear.

Here's the problem:
When I move the carriage, the beam is no longer centered in the second mirror. I don't see how the beam ever could be aligned correctly, as the beam and coming into and out of the first mirror is not in the same plane as the carriage.

It would seem that I would have to raise the second mirror (not just tilt it) or lower the first mirror, and I don't see a good way to do that.

If anyone has any ideas, I'd appreciate it greatly.

[SimonArthur]

I've attached a diagram that shows what's going on; hopefully it makes more sense than my explanation.

[MacGyver]

Aim for the first mirror. Send the carriage to the far end. Using the first mirror adjustment screws, aim for the center of the second mirror. Send the flying head to the far end. Using the second mirror adjustment screws, aim for the center of the down-angle mirror. This process gets repeated until all mirrors have been adjusted.

[SimonArthur]

MacGyver: what I don't understand is that Mirror #1 (the stationary mirror) is in a different plane from Mirror #2 (the mirror on the carriage). It is slightly higher up. I have attached a photo taken from straight on from the front of the machine that demonstrates this, as well as a revised diagram that I hope is clearer.

Thus, I can see no way to make the laser hit Mirror #2 on-center except by raising Mirror #2 or lowering Mirror #1. Is this correct?

Or should I be able to do all the adjustments by managing the tilt of the mirrors with the thumb screws?

[MacGyver]

If the mirror is not in the same plane, there's not a whole lot you can do other than physically move the mount. Without being in the same plane, the beam will not be aligned towards mirror #2 as the gantry axis slides up and down. Slight differences in height can be accomodated, but if that picture you attached is accurate, the difference in height is half a mirror or more... that's not correctable with adjustment screws.

See if they assembled the mounts themselves incorrectly, maybe with extra washers, or maybe not enough. Make sure both mounts are fully seated.

[Mrebeiro70]

I have the Rabbit 4030 that is very similar to yours. My machine also had the tube and first mirror higher than the others.
My tube broke and when I put in the replacement I couldn't get the rubber cushions around the tube and in the brackets like it was originally. So my new tube ended up being lower than the first mirror but now inline with all the others.
Just lower the mirror bracket about an 1/8 of an inch or so. I can't tell you how good the original alignment was before this happened since my first tube was broken, but after the adjustment the new tube is now inline with the carriage and everything is aligned perfectly.

It did take a couple hours to get the mirrors aligned due to the crappy design and machining of the parts. I also went through a lot of tape and little wooden disks but it's doable and these Chinese machines work surprisingly well once tuned up and you figure out the confusing software.

[SimonArthur]

Well, many hours and little discs later, I got it working. The design almost seems designed to frustrate the operator, and the instructions and video don't really help. You have to get mirror #1 aligned in 2 planes with mirror #2, in addition to adjusting its angle.

Thanks for the encouragement and advise, everyone.

[MacGyver]

I've found it much easier to use a laser pointer in place of the tube for initial alignment... it helps to get everyone in the same plane.

[Vincent de Kler]

I found that leveling the machine first and then getting all the tops of the mirrors on the same height using my laser level device (the type that draws a red line) positioned diagonally from the front of the machine , made it a whole lot easier. I imported a Chinese machine and was ready mentally to reset the whole lot. I thaink that also helped.

[Tweakie]

I started from scratch with mirror positioning as well as allignment. I made a frame (the same diameter as the CO2 tube) to sit in the tube mountings which held a small HeNe laser and used the beam from this to set up everything. Once done I replaced the HeNe with the CO2 and only one small adjustment of the final mirror was necessary to allign the beam within the 1.5mm diameter air assist nozzle.

Tweakie.

[Vincent de Kler]

Yes I also found that it is easier to get all the mounts on the same plane and in line(side -on and top) and then adjust the mirrors. This meant that some of the mounts had to be moved/lowered/ lifted etc. I like the plan of using the red dot pointer in a bracket exactly the same as the tube. I think I will cut myself a bracket like that to house the green diode laser I have. This will assist in lining up the laser beam(next time) as the beam of the green diode can be seen. The best ideas are the common sense ones. Thanks for that tip Tweakie

[GuiBerlin]

Here is how I did it :

[zax15uk]

That's creative, and effective. :cheers:

Zax.

[vincenttor]

thanks for these tips,

i just bought/recieved my 40w laser from llc company
they say its fired /tested in factory but the first mirror was beaming atleast 2 cm above the second mirror .
can it be that unadjust by transporting it from china to the netherlands ?
anyway got about 18 hours of time sitting in the adjusting and getting the machine to work but still no real nice results
going to order a green laser also with a more visible beam.

[zax15uk]

Vincent,

I am sure it was aligned at the factory but then moved in shipping.

They haven't copied anti-shake washers yet in China and apparently loc-tite isn't available either so this is pretty common.

Zax.

[vincenttor]

yes, i found it quite interesting that there was hot glue used to keep the screws tight.
most of m was allready gone before i touched it :stickpoke
I do infact got another major problem called EMI
sometimes my machine works but 98% of the time it doesnt.
trying to work it out with the help of llc but i don't know what to do anymore.
think im also going to open a topic about it because i really can't wait to use the machine

[zax15uk]

What exactly does it do when you say it doesn't work?

It is essential that you have a good ground connection, and that the ground is to the same location as the PC.

If you describe the symptoms I may be able to point you in the right direction.

Zax.

[vincenttor]

i will open a topic for it otherwise i steal the topic (nuts)