without a rotary. Haven’t tried this in a long time. I have some extra time and I thought I’d play around. I’m using a 200mm lens on my 50 Watt Fiber.
First off, when I got the laser focusing dot where I think it should be, I made a 5mm x5mm square, and fired off a shot. Wow… No cleaning needed. It just blew the powder coat right off. I wasn’t expecting that. I usually engrave my tumbs with a 100mm lens with a rotary.
Anyway when I use my 100mm and a rotary, the lettering at the top is around 75mm across. Without the rotary, to get it to properly engrave I have to shrink down the lettering to around 58mm. Quite a bit smaller looking than my customer is used to. I’ve already done 50 a couple of weeks ago with the rotary.
I’m waiting for her balance of her order to show up. Thought I’d experiment a bit today.
Should I be able with a 200mm lens to get that 75mm’sh text to engrave? I’ve enabled cylinder correction with these settings: Mirror distance 340.00 / Object diameter 120mm. I’ve never used it since I always use my rotary.
Thoughts? This process would be so much faster. Around 20 seconds -vs- 2:30 seconds.
The advantage of the rotary is that the focus distance remains the same. If engraving on a fixed curved surface, the sides will quickly go out of focus. I cheat doing curved surfaces with my Sculpfun diode lasers, but they are known for exceptionally long DOF (depth of focus) values.
The 2:10 longer burn time suggests you are using rollers. If this is true, you might be able to shorten the time with a chuck rotary. If you are already using a chuck, I have no idea why it is taking over 7x longer.
I use a Chuck Style Rotary. If I find that vid I’ll post it here of someone just laying the tumbler down, and throwing a logo on it. I really didn’t pay much mind as to the width of the logo they did to be honest.
With my rotary, my settings are Speed 500, Freq 400, Max Power 25, LPI 0.0250. I do understand Focal Length. In my previous life, I was a professional photographer.
I have some tumblers I can screw with to see if I can get the speed quicker. Her order won’t be in for another 30 days.
Skip to 2:42 in the vid. Those are my type of 20oz tumblers as well.
I threw on my Rotary, and it took 4:48 seconds, @ Speed 1500, Freq 50, Max Power 75, LPI 0.0500. It’s been around 3 weeks since I did some of her tumblers with my 100. I think it was over 3:00 each, best I can remember.
If I have to use a rotary, I have too. Doesn’t matter really. I was more curious than anything.
If you are talking about a fiber laser, with a 300X300 lens and using the cylinder correction tool you should be able to get a pretty good sized engraving on a curve.
I might try to reduce the artwork at the top by 25%, and see what it looks like. The artwork down below that engraves fine. The text at the top is where I don’t have enough Focal Length on the sides.
What size lens are you using. 200mm could be an F200mm or it could be a coverage of 200mm square.
Another thing that may make using your rotary substantially faster is a larger is using a larger split size. Use the lenses dof for figuring out a different split size.
With Lightburn when the rotary needs to change, it’s given control back to Lightburn, which turns the rotary and then gives control back to the board. A larger split size makes for a faster job.
