Lens/Mirror

[Mark Taylor2]

I'm attaching a photo for this. I changed the tube and checked the alignment at mirrors 1 and 2. I put a bit paper in front of the mirror/lens head and checked that. All were dead center at both upper left corner of the cutting area and lower right corner of the cutting area (near and far). No beam out of the lens for cutting or etching. The head was loose so I re-seated it. Still no beam out. I removed the lens and put a piece of thermal paper on the underside of the top assembly (mirror part) and when I look down, I see that the burn is upper right.

I've tried spacers on the mirror opposite the burn area thinking angle of beam in = angle of beam out but no joy. I've disassembled the lens/mirror head and re-installed it several times checking everything for "square and level". Everything seems to be square and level.

Any ideas on how to fix this to get the beam centered so it will hit the center of the lens? I'm stumped.

Machine is a MicroMark Laserkniife (glorified K40) with an upgraded power supply (Automation Tech), 45W/50W tube (Lightobject) and chiller (Lightobject).


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[Bill George]

Did it ever work or has something been changed?

[Ron Gosnell]

Theres a couple of good articles on this site if you can find the right search terms. Pretty detailed.

[Matt McCoy]

I don't see the pic -- maybe since I'm on a tablet. If I follow you correctly, you have good alignment all the way to mirror 3, but not through the lens. If that's the case, mirror 3 will need to be adjusted to hit the center of your lens.

[Bill George]

No pictures posted even on a PC laptop seen.



Happy New Year!!

[Mark Taylor2]

Facepalm moment... photo added.

[Matt McCoy]

From the pic, I would guess the path is blocked by the nose cone. Might try a test pulse without it to see if you get a mark. Mirror 3 will need to be adjusted so the beam hits the center of the lens.

[Kev Williams]

for the life of me I can't tell what I'm looking at in that picture--can't tell if the camera is under the lens or above it? I see an oval that may be the mirror, if so, then is this a cellphone pic below the lens?

That all said, if the beam is hitting all the mirrors in the center, then the last mirror- over the lens- needs to be moved laterally (to move the beam left or right in the X axis) and/or the tilt must be adjusted (to make the beam perpendicular from top to bottom).

[Jerome Stanek]

when I got my laser I couldn't figure out why it was cutting on an angle until I checked the last mirror placement. they had the mirror to far back and to get the beam centered it had to hit the lens on an angle not straight down just had to move the mirror forward

[Mark Taylor2]

I'm starting again at the beginning of the mirror alignment. This is most puzzling is why everything lined up and looks good until I get to the final mirror.

I tried shimming the mirror and got the beam centered, then when I put the lens in, the beam shot off at angle. I'm wondering if the lens/mirror (not sure of the right word) "cart" somehow got wacked out of adjustment but I don't have any info on adjusting it nor what screws to turn.

[Kev Williams]

can you show us a few pics of the full laser head assembly?

[Mark Taylor2]

Pics are here. What I've discovered so far is that the tube sank into it's mounts due to the water. There's foam padding. So that's partly fixed it. Everything (beam wise) is where it should be until it hits mirror#3 and goes to hell in a handbasket....

Here's the pictures of the laser head. The mirror/lens is sitting below it.

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[Bill George]

Pics are here. What I've discovered so far is that the tube sank into it's mounts due to the water. There's foam padding. So that's partly fixed it. Everything (beam wise) is where it should be until it hits mirror#3 and goes to hell in a handbasket....

Here's the pictures of the laser head. The mirror/lens is sitting below it.

350573350574

Sank into the water??
The beam needs to be in the center of the mirrors verified by putting masking tape over each and finding the burn mark. The last one is the hole in the laser head on top entering the hole and then hitting the mirror. Is it centered entering the hole? If so the mirror on the back needs to have the burn mark centered and directed down the tube. Start at the tube and work forward to the laser head. Good write ups on here and on Ray Scotts website. You should not need to shim or otherwise adjust that last mirror.So a new tube was installed, is it the same height as the old one if not did you make a adjustment to correct?

[Mark Taylor2]

Not sank into the water.. into the foam mounts. I had checked the alignment when I put in the new tube and then had to wait almost a week to do any testing as I was waiting for the chiller. I got everything reset, re-centered, and the beam is almost dead center on the lens.

[Mark Taylor2]

I do believe I found the problem... the #3 mirror appears to be delaminating. I've ordered a new one. I realized that my results were inconsistent and was struggling to lock down and remove any variables in the aligning and testing. I finally noticed that the mirror front piece and the substrate were not, for a lack of a better word, aligned. If I pressed it on edge, it moved and I could get it re-centered but after handling it and testing, things shifted. I'm not sure what caused this. Heat? Minute scratches on the mirror surface? Age? Who knows.

[Bill George]

The K40 either being sold as a K40 or Micro mark uses the cheapest components they can find.

[Bert Kemp]

Mark I know you already have this laser, and you think putting ,mirrors, lens, control brd and the like will make it better and yes it will but its a never ending money pit. Next will be the cheap rubber rollers will start to wear and that will cause problems that you will wonder whats going on, then the belts wear our it goes on and on and on. By time your done you ave 5 or 6 k in it and it still isn't as good as a Chinese import for 3 K. Sorry I keep telling you this but I'm just trying to get you to give up that micromark and get a real laser you'll be so much happier and the money you spend on it only hurts till your lasering away pain free .lol. Trust me I know. I cringed when I spent the money for my rabbit, more so then most cause it doesn't make me any money. But it runs and I don't have to spending money fixing it all the time. Sell this one on CL for what ever you can get then add a few bucks and get something half way decent.:)

[Mark Taylor2]

Kev,
The first picture was an overhead shot as straight down as I could get it. The mirror was removed to see the burn spot which is at the 2 o'clock position in the tube.

Bert,
I know deep down inside that you are right. I'm considering that as a possibility. Just need to figure this out for the knowledge and so whoever I sell it too, doesn't give me grief that it's not working properly.


Currently, I found the adjustments for the mirror/laser carriage. Every screw was loose. I've re-tightened them and checked, double-checked everything to get things square. It appears that the mirror needs shimming, but with the de-lamination on it, I'm holding for now. I think I need a few beers and consider what's the best way to shim and also to consider Bert's suggestion.

[David Somers]

Mark,

It is hard to tell, but my eye brows go way up when you say the mirror needs shimming. That suggests things are not just off, but wayyyyyyyyy off and you need to go back to square one. and if you do have a mirror that is delaminated there is no sense fussing until you replace it. That is like putting a brand new tire on a car whose wheel alignment is way out. Pretty fruitless.

I think someone earlier suggested the Rabbitlaserusa.com web site (Ray Scott) for a good explanation of aligning your mirrors from laser tube on to the cone. all you need is some masking tape to do it. Since it is an inexpensive laser, Once that is done I would check to be sure your table surface is on a plane that is parallel to the XY axis. And I do mean it needs to be on the money if you are going to get consistent cutting from every corner of the machine. The focus on any laser is VERY shallow and it doesnt take the table being off by a smidgeon to affect things adversely and drive you crazy. (I love the word Smidgeon!! Dont know why!! <grin>)

Dave

[Mark Taylor2]

I've been listening to the sage advice here and reading other related topics. What struck me was Dave's comment about "level" on the machine itself. I have the laser on a Skill folding work table.. one of those plastic/metal things and my curiosity kicked in. I leveled the machine when I first set it up. Rechecking everything from the chassis up says "not anymore". I dug out a piece of 3/4" MDF particle board and set it on the table and then reset the machine on it. It's now level from bottom to top and all the internal spots I can find to set a bubble level on. Hmm... <facepalms> I'll let thing sit overnight before going any further with the tape/cash register paper alignment checks. I have learned through experience to wait 24 hours after resetting anything (taking things out of jigs is most notorious for me) to let things settle a bit.

[David Somers]

Mark,

The key isn't so much that it is level as it is that your honeycomb surface is absolutely on the same plane as the XY axis of your gantry. Though certainly having the machine itself on the level is helpful. Annoying to have things rolling down hill all the time! <grin> If the honeycomb is not on the same plane as the gantry then your point of focus will vary from corner to corner to corner and you will get variable performance all over the table. A small amount makes a BIG difference. The depth of field on a 2" lens is very small.

[Gary Hair]

I've been listening to the sage advice here and reading other related topics. What struck me was Dave's comment about "level" on the machine itself. I have the laser on a Skill folding work table.. one of those plastic/metal things and my curiosity kicked in. I leveled the machine when I first set it up. Rechecking everything from the chassis up says "not anymore". I dug out a piece of 3/4" MDF particle board and set it on the table and then reset the machine on it. It's now level from bottom to top and all the internal spots I can find to set a bubble level on. Hmm... <facepalms> I'll let thing sit overnight before going any further with the tape/cash register paper alignment checks. I have learned through experience to wait 24 hours after resetting anything (taking things out of jigs is most notorious for me) to let things settle a bit.

What you actually need to do is to ensure the distance from the lens to the bed is the same across the entire bed - that is what most people refer to when they ask if your bed is level - but it's actually parallel and has nothing to do with level. My guess is the first person to use the term "level" didn't know how to describe it correctly and thought "level" sounded right... If the laser is sitting at an obvious angle then it could be an issue, but otherwise it just needs to be on a flat, secure, fairly level, surface, but it's certainly not that critical to get any part of it level.

[Kev Williams]

You could mount the laser from the rafters in your garage and get the laser to work perfectly, as all the mirrors can be adjusted to make the beam hit the lens dead to rights centered and perpendicular anywhere within the machine regardless of the beam's origin...

It's just easier if the laser tube IS fairly level ;)

[Bill George]

Of course the thought for the day either if its level or parallel with the table or whatever is the machine built good enough to stay where its set? If you move it does it hold those settings? Sometimes you need to stop, step back and think.... what is my time worth? Why do I put up with this? Believe me I have had those moments.

[Mark Taylor2]

I just want to say thanks for the help and input on this problem. I've solved it by tightening and checking every nut and bolt and re-aligning and adjusting. It was a learning experience but everything seems to be steady even after sliding the workbench out from the wall and back several times.

As for the future... this machine will probably be replaced or supplemented by a BossLaser or something equal once we learn the status of my wife's health. I've been encouraged to get into custom cutting for a very niche hobby and am working on learning all I can including some of the more "obscure" features of CorelDraw.

Anyway, thanks again. Sawmillcreek members are a very special breed because of their willingness to help out.

[John Lifer]

I'll say again, that I've been pleased with my Chinese laser from Ray Fine. You can get a 400x 600 80 watt machine for under $2k delivered to us port. You're in Oregon, so freight on up from LA wouldn't be much and duty/fees would only be a few hundred. Well under $3k. (Shipped to me in Arkansas would have been about $2900 total). I'd do that rather than keep spending on a k