Alignment problems and tube level

[Jonathan Bowen]

Does the tube being out of level cause allignment issues? I am upgrading my 40 watt Hurricane Agnes to a 60 watt tube and can't get it to allign. I got it close but the beam is clipping the bottom corner of the mirror. The table will not let me adjust it into the right position. I'm working on making a new bracket to shift the 1st mirror to into the tube a bit more. I might give up on that and just drill new holes into the bracket and tap them for new screws. I don't have metric taps. The 2nd mirror bracket is maxed out to the outside so I can't more that anymore. I also can't level the tube without making some heavy modifications. The tube being taller means it sits lower and if I drop the second bracket anymore then I hit the pressure sensor. I've thought about raising the tube a bit but I'm hitting the 1st mirror really nice and if I shift it up then I'll still be off mirror slightly on the second one.

[Dan Hintz]

In the end, what's important is the beam is parallel to the bed once it leaves the last stationary optic.

[Jonathan Bowen]

that is what I figured but its getting really frustrating. Been at it for 2 days and I can get close but never spot on. Still losing power due to bad alignment.

[Jerome Stanek]

My tube was angled up just slightly and I worked for a week trying to align it. I finally raised the back of the tube and got it level and only took about an hour to get it aligned.

[Rich Harman]

The tube does not have to be level. The first mirror can steer the beam left/right, up/down. Reci recommends that the tubes be angled slightly, rear end down so as to help with evacuation of air bubbles in the water cooled tube.

If you can adjust the beam up or down to hit the center of the second mirror then the "levelness" of the tube is not the issue.

[Jonathan Bowen]

Well 2 days of fiddling with the stupid thing and I got it close. I had to push the second mirror bracket to it's limit. I ended up reaming out the mounting holes. I have about 1/16" left on one side. The tube is currently elevated slightly on the front end. I'm still a bit under power but I might just be expecting too much from the 60 Watt. According to Hurricane's manual their 60 Watt should be able to do 15mm/s on acrylic at 100%. However, I have the tube set to about 20.5 or 21 amps. So their numbers are probably set to their power supply and those are not calibrated and probably run hot. Not sure what others experience but considering I was running about 5mm/s I;d say cutting my production times in half is worth all the effort. Not really worth it financially but only because I broke a tube because I'm an idiot. Still on the fence about if its riskier to remove the tube in a week or so when I have to move the machine to a new location or if I should just leave it in.

[Rich Harman]

I cut 1/8" acrylic at 20 mm/sec, I could cut faster but this speed gives the best cut quality - the parts fall out on their own when removing the material from the laser bed.

I am sure it is milliamps not amps that you meant, or .021 Amps. I think if you are reading the meter, then that is a better indication of the power going into the tube rather than the power setting. For example I have my power supply adjusted so that a setting of 80% is 24 mA - which is about 100% of the power recommended for long life of the tube. I could adjust the trim pot so that a 98% power setting equals 24 mA, it doesn't really matter what the percent says, only what the actual current going through the tube is. The only time that I don't use full power to cut is when the material is so thin that the speed required would be too high - like card stock, paper or foam.

I will be moving my laser in the next couple months, I will leave the tube in place when I do.

[Jonathan Bowen]

Yes but your tube isn't housed in a PVC tube with 3 screws holding a plastic flange onto the side of the machine :) There is less risk in taking the tube out for the move so I will probably do it. I'm just really paranoid because this setup didn't work out as great as I had initially planned. it's just a bit more flimsy then I'd like and having broken one tube already it has me thinking the worst. I'll just have to be super careful so I don't snag anything like the electrode connector on the way out.