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Chris Ward3
09-29-2014, 7:43 PM
I have been trying to laser a moose antler. One of the problems that I am having is getting the settings right. If I want to engrave something deep down and need the table to be down what settings do I use?
I have tried:
Wood (whatever type)
Material Thickness: 1”
Fixture Type: Custom
Height: 7
But it occurs to me that if I were trying to engrave the top of an 8" box I would use the same settings. This doesn't make sence!

Can anyone understand my dilema and offer some suggestions or solutions?

So far, I haven't been able to make a mark on it. So I tried a wood plaque at the same depth and it did not laser properly either.

Scott Shepherd
09-29-2014, 7:48 PM
I have been trying to laser a moose antler. One of the problems that I am having is getting the settings right. If I want to engrave something deep down and need the table to be down what settings do I use?
I have tried:
Wood (whatever type)
Material Thickness: 1”
Fixture Type: Custom
Height: 7
But it occurs to me that if I were trying to engrave the top of an 8" box I would use the same settings. This doesn't make sence!

Can anyone understand my dilema and offer some suggestions or solutions?

So far, I haven't been able to make a mark on it. So I tried a wood plaque at the same depth and it did not laser properly either.

Not possible. Your focal length cannot change. It's exactly that, it's the "focal point" where the beam is in focus. 8 1/2" down, the beam is 1/4" in diameter and I don't think you are going to get that to work. You head needs to be the focal distance from the area you are engraving.

Chris Ward3
09-29-2014, 9:01 PM
Thank you Scott,

I thought that was the case. So please excuse my ignorance, but, are other makes of laser engraving machines able to change the focal point to work in the situation that I described? If so, I would have to think that they are more versatile and maybe I should have purchased something different. I must say that this machine has been very dependable for what I have used it for until this situation.

Thank you for your expertise. I was going to reply to you from another thread with my question while I was searching to see if I coud find my answer but I didn't think I should hijack another thread with my dilema. I seemed to think that you would be the one to ask : )

Scott Shepherd
09-29-2014, 9:13 PM
Thank you Scott,

I thought that was the case. So please excuse my ignorance, but, are other makes of laser engraving machines able to change the focal point to work in the situation that I described? If so, I would have to think that they are more versatile and maybe I should have purchased something different. I must say that this machine has been very dependable for what I have used it for until this situation.

Thank you for your expertise. I was going to reply to you from another thread with my question while I was searching to see if I coud find my answer but I didn't think I should hijack another thread with my dilema. I seemed to think that you would be the one to ask : )

Nope, they all work the same. You can buy different focal length lenses like a 4" lens, but nothing it going to focus 8" down. You bought a great machine! It should serve you well.

Mitchell Tutty
09-29-2014, 9:20 PM
Depending on how important this job is to you it may be worthwhile creating a jig to prop the antler up at a certain point.
This is pretty much your only viable option, even with a 4'' lens your beam is going to far too out of focus to get a reasonable quality etch.

Bert Kemp
09-29-2014, 9:26 PM
can we get a picture of the antler on the bed of the laser?

Kevin Gregerson
09-30-2014, 12:36 AM
So, some might consider turning off the auto z in the systems tab. Then, getting some magnets for bypassing the magnetic interlocks on the doors. Then, while wearing safety glasses setup and use as needed but keeping hands away.

Kevin Gregerson
09-30-2014, 12:38 AM
Not possible. Your focal length cannot change. It's exactly that, it's the "focal point" where the beam is in focus. 8 1/2" down, the beam is 1/4" in diameter and I don't think you are going to get that to work. You head needs to be the focal distance from the area you are engraving.

Further more the 4 inch lens will increase the distance which you can mark but it also increases the spot size and decreases the power density at the focal point.

Scott Shepherd
09-30-2014, 8:14 AM
Depending on how important this job is to you it may be worthwhile creating a jig to prop the antler up at a certain point.
This is pretty much your only viable option, even with a 4'' lens your beam is going to far too out of focus to get a reasonable quality etch.

I agree, there might be a way to put it in there and put a mark on it, it might just be in a slightly different place than originally wanted.

David Somers
09-30-2014, 10:28 AM
Chris,

Is the issue you are having that your gantry and lens head will hit the upcurved antler tines if you don't have a suitable distance between the lens and the surface you are cutting/engraving?

If that is the case, you should be able to limit the movement range of the gantry and lens head through the lasers controls. That would allow you to raise the table up to a better height and use a shorter focal length lens and get a better quality engraving. The limits on the movement of the gantry and head would prevent the laser from hitting the tines. You could fold some cardboard into the rough shape of your antlers and use that as a test to be sure of your settings if you wanted some reassurance before you used the real tines?

Scott....am I off base on this thought?
And Kevin Gregerson....as a ULS rep, can you steer Chris in the right direction in your manuals for those movement limits in Chris's ULS model?

Chris, if all my assumptions are correct, then you are faced with getting everything aligned correctly on the table. One thought would be to take a sheet of paper of suitable size and lay it on the table aligned to your X and Y rulers, and then lay your antler on top in the position you want. Use a pencil and outline the antler on the paper, with a few reference marks so you could reposition it accurately if you removed it.

Then take that sheet of paper and scan it into your computer. lay out your engraving overlayed on the scanned image. Put the paper back into the laser, lay the antlers on it using all your reference marks to accurately reposition it, and now your graphic should match up correctly with the antler. You could always do a very light test of your graphic on the sheet of paper to be certain you have it right before you commit to the actual antler. Or put some blue painters tape on the antler and very lightly test on that.

And lastly....fair warning. I do not actually have a laser in hand yet. I am just trying to reason out a relatively simple approach for you with this problem. With luck, someone else will read this and say "oooh! Got a better way to do that!!!!" and then you and I will both know a bit more!!!! <grin>

Dave

Kev Williams
09-30-2014, 10:58 AM
Not to sound condescending, but I think some of the issue may be the perception that laser beams are always straight and narrow, like those at laser light shows, or laser pointers that shine the same small dot 100' away as it does 2" away. (or a mile away as many pilots can attest) Our lasers are straight and FAT, until they hit a lens to funnel the beam down to a tiny point. After that point, the beam funnels in reverse, getting wider and wider as space increases...

Kevin Gregerson
09-30-2014, 11:22 AM
I have been trying to laser a moose antler. One of the problems that I am having is getting the settings right. If I want to engrave something deep down and need the table to be down what settings do I use?
I have tried:
Wood (whatever type)
Material Thickness: 1”
Fixture Type: Custom
Height: 7
But it occurs to me that if I were trying to engrave the top of an 8" box I would use the same settings. This doesn't make sence!

Can anyone understand my dilema and offer some suggestions or solutions?

So far, I haven't been able to make a mark on it. So I tried a wood plaque at the same depth and it did not laser properly either.


So, have you got that tool that has a shoulder on it that you put on your materials?

If so you will want to turn off the auto z in the systems tab on your computer. You want to raise your material to the shoulder of that tool. The reason why is because your laser beam is a Concave see image below for descriptions, and your best focal depth is around .2 inches on wood so you want to be marking on a piece that's relatively level, the correct distance from the laser head and out of the way of the gantry. You can go as far as removing the Z table to get a few more inches inside the machine if you are working with things like the antler. Just remove the connection for the magnet underneath, then there are 3 screws on the bottom right and two on the left top of the table.
297589

Chris Ward3
09-30-2014, 5:46 PM
Wow, thank you all,

I was under the impression that I would be able to, using settings, focus the laser down the 9" (8 actually because the antler is about an inch thick) to mark it in the bowl of the antler. When I position it bowl side up the antler stem (where it was cut nearer to the skull) sticks up that much. I now know that the table depth only allows for the position under the focus area. It would be possible to laser etch it in the bowl only if the lid of the laser is open to allow the stem part of the antler to stick up and the bowl area to be in focus. I am going to try to etch the back of the antler just to find out how badly it smells and how good of an etching I can get to see if I want to explore this any further. If it looks good and I can stand the smell, I may want to quiz you Kevin, on how I might do the bowl side.

Again, I thank you all so much. This is something I probably should have known already about the focus but hey, I do now.

Now that I know how great it is to get advice here I am sure you will hear from me again. And as I read the threads, if there is something I can share, I will be happy to do so. I think most of you know more than I do.

Chris Ward3
09-30-2014, 5:51 PM
Hi Kevin,

No, I don't have that tool. I think the only way for me to laser the bowl would be to do it with the lid open. I think you said that was a possibility, with alterations and great care. I am going to laser the back side of the antler, see how good it turns out, how smelly it is, and then decide if I want to try to do any antler bowls. It is a pretty valuable customer of mine who is interested in this so I may get back to you, if that is ok?

Thank you

Scott Shepherd
09-30-2014, 5:57 PM
Chris, you're right, you'd have to do it with the lid open and be careful on the movement. It's a doable thing, but a little challenging.

As for the engraving, it'll engrave nice. I've done deer antler knife handles before. They work well. I don't recall the smell being anything etched in my brain, so I think you'll be fine.

Kevin Gregerson
10-01-2014, 5:20 PM
Hi Kevin,

No, I don't have that tool. I think the only way for me to laser the bowl would be to do it with the lid open. I think you said that was a possibility, with alterations and great care. I am going to laser the back side of the antler, see how good it turns out, how smelly it is, and then decide if I want to try to do any antler bowls. It is a pretty valuable customer of mine who is interested in this so I may get back to you, if that is ok?

Thank you


If someone wanted to open the lid and run the system in a class 4 method they would need to bypass the magnetic interlocks. To do this would require magnets and some eye protection.

Kev Williams
10-01-2014, 7:13 PM
I gave up on stuff actually fitting IN the laser LONNNGGG ago...
297703297704

David Somers
10-02-2014, 10:08 AM
And you guys should see how Kev brands horses and cattle! Ingenious!
<grin>

Dave