View Full Version : Nose cones etc

Kev Williams
04-10-2016, 11:30 AM
The 'is the 80w Trotec 40w' thread got derailed a bit towards cutting and nose cones-- I was going to add to it but decided to start a 'nose cone' thread instead. :)

I've said this before- I've found no use whatsoever for a nose cone. I laser engraved with my ULS and LS900 for 10 years before I ever saw one. I've tested my Triumph using and not using its nose cone, and the only effect I've noted is I have less power with the cone, which tells me part of the beam (which is centered nicely in the cone's tip) is hitting the cone before it gets to the work. Maybe my tip opening is too tight, I don't know.

My ULS and LS900 never had one, and both machines (19 and 12 years old) are still going strong on their original lenses. The ULS doesn't have air assist, but 25w machines don't really need it. What both machines have is a great air evacuation design. Both machine's air enters from the front of the machine, in front of the table, and the air outlet is in the back, level with the 2" focus point of the lens. No air moves UNDER the tables. All the air moving in the machine sweeps across the top of the table, and your work. The air flow draws smoke straight back and out, never reaching the lens.

My LS900 has, in my biased opinion, the best designed laser cabinet in the business. First, no cone. Air assist is is adjustable on the machine, uses very small (1/16"?) air tubing that can be connected directly to 125psi and to the machine. The air nozzle is a copper tube, angled toward the back of the machine, and can be rotated up and out of the way if needed. If you plan to do a lot of cutting (I don't, but...), note the 50c sized hole toward the upper-left side of the table. That hole is connected to the air line visible under the table that's part of the exhaust system. At the back of the cabinet, there's a round tube to the left of the stepper and it's brace, connecting a secondary vacuum hose as shown. I never use this, I just put in place for the pic, and is missing the flattened-funnel looking end cap that sits about 1/4" above the work just in front of the beam spot. There's a blast door that you can close that now diverts the suction to the hose ports. Using a cutting grid table top, you can cut gobs of plastic or wood, and the is smoke drawn right at both ends of the cut. The blast door is never fully closed and will still draw plenty enough air to evacuate any residual smoke. I've never used the upper hose, but the lower hose works better than you might expect. The upper hose is good for low-speed rastering or vectoring only. I guess one of these days I should hook up the top hose and see how well it works! But just because of the great basic exhaust airflow, I only have to clean my lens and it's mirror maybe twice a month. The other mirror I clean maybe every 3 months. And I believe that air assist outside the lens with the airflow angled makes much more sense than blown straight down. And I may be wrong, but because of my tests, I also believe that if your coned lens is getting hot, it's because the CONE is getting hot, not the lens itself...
Right or wrong, these are my opinions-- :D Yours?


Dan Hintz
04-11-2016, 6:17 AM
And I may be wrong, but because of my tests, I also believe that if your coned lens is getting hot, it's because the CONE is getting hot, not the lens itself...

If the cone is getting hot, it's because the beam is hitting it... you need to realign. If the beam was getting the lens hot enough to heat the cone, you need to replace the lens because it's trashed.

Gene Uselman
04-12-2016, 3:17 PM
Very interesting. So you do not normally use the vacuum hose that goes to the head? I would also love to see some closer pix of the head area- maybe from a couple angles? Thanks Gene