Laser engrave a belt help

[Bert Kemp]

I'd like to try and laser engrave a belt. My Problem is my engraver is pass thru front to back and I can only engrave about 14" of the belt at a time. So I need a way to move the belt forward and keep everything in line and matched up. any ideas on how to do this would be greatly appreciated. https://leatherworker.net/forum/uploads/emoticons/default_smile.png

[Grant Wilkinson]

Since I don't know your machine or the software you are using, the following may be completely useless, but I'll have a go.

I've done similar projects in wood using a CNC router. I use the tiling method shown here:

https://www.youtube.com/watch?v=3jhnKr4fc_c

I didn't have the same cam program that Peter has, but I could still use the concept.. Maybe you could mount the belt to a board, so that you could have a reference hole/mark and run two "toolpaths" that way??

I have a small laser attachment for my CNC router and run Lightburn software. I've never tried this using LB. If you do get some method to work, please report back.

[Mike Null]

Bert
Why can't you run it in the x axis?

[Doug Fisher]

One possibility is to make jig that allows you to feed the belt through your machine in a straight line and then use the pass through feature of LightBurn.

https://www.youtube.com/watch?v=n__saOKVupA

[Bert Kemp]

Grant my machine and software are listed in the post. Looking at that video it gives me ideas but since I can't lower a tool into a hole for perfect positioning so its still going to be hard.

[Kev Williams]

don't usually have this issue with my lasers, but I've had to splice together many large engravings on my tool machines, this one was fun-
453685 453686453687

what you need first (if possible) is a reliable straight edge that you can move your work along.

Then, you need to map out how much you can engrave before you have to move the work, and leave enough room for the LAST thing you engraved to fit the engraving area next, because you need to line up the next section TO the last thing you engraved. Example: Say this below will be done in 3 sections, and I've chosen my 'break points':

Now is the time for all good men to come to the aid of their country

--so I'll engrave
Now is the time for all

then setup the next section to fit
all good men to come to

So, all is my alignment point for the next section;
once I make sure the all would engrave in the same place after the material move, then I'm ready to engrave the
good men to come to

--then move the work to fit
to the aid of their country

then make sure the to is aligned after the move, then engrave
the aid of their country

hope that made sense :)

[Bert Kemp]

Because my pass thru is front to back
Bert
Why can't you run it in the x axis?

[Bert Kemp]

Lightburn won't work on my machine:( but yes some sort of a jig is what I have to come up with
One possibility is to make jig that allows you to feed the belt through your machine in a straight line and then use the pass through feature of LightBurn.

https://www.youtube.com/watch?v=n__saOKVupA

[Bert Kemp]

I kinda sort of maybe LOL understand what your sayin but doing it from left to right would be a lot easier I think then top to bottom
don't usually have this issue with my lasers, but I've had to splice together many large engravings on my tool machines, this one was fun-
453685 453686453687

what you need first (if possible) is a reliable straight edge that you can move your work along.

Then, you need to map out how much you can engrave before you have to move the work, and leave enough room for the LAST thing you engraved to fit the engraving area next, because you need to line up the next section TO the last thing you engraved. Example: Say this below will be done in 3 sections, and I've chosen my 'break points':

Now is the time for all good men to come to the aid of their country

--so I'll engrave
Now is the time for all

then setup the next section to fit
all good men to come to

So, all is my alignment point for the next section;
once I make sure the all would engrave in the same place after the material move, then I'm ready to engrave the
good men to come to

--then move the work to fit
to the aid of their country

then make sure the to is aligned after the move, then engrave
the aid of their country

hope that made sense :)

[Glen Monaghan]

...since I can't lower a tool into a hole for perfect positioning so its still going to be hard.

I've used two similar approaches for lasering. First time, I needed to engrave a shape that would be cut out later so I just added small squares engraved in waste areas of each "tile" or section. Then, after repositioning the substrate for the next section, I first ran the laser at zero power with the red dot turned on to trace the reference squares in their new position so that I could fine tune positioning as necessary before engraving the next section. That worked but took a lot of fiddling and pucker power.

Second time, I didn't have "waste" areas so used a carrier with notches along the side, thinking that it would be easier to just slide the substrate and carrier until the next notch lined up with an index along a straight edge (the same idea as in the video but I had to use a carrier and created the notches in advance). The flaw was that it was highly dependent on the precision of the notches, and I wasn't precise enough for perfect alignment. Would work great if, for example, you also had a large enough CNC to make the carrier with precision spacing, or if your work piece allowed you to cut the notches along the edge (or, alternatively, cut small holes somewhere in the interior, similar to the CNC in the video) of your substrate on the fly as you engraved each section; you could then align the notches or holes with fixed index pins for each subsequent section.

You could tape your belt onto a long board, which would keep the belt straight, provide a fixed reference side, and (assuming the board was wider than the belt) provide space to create reference marks next to the belt, along the edge of the board, for repositioning.

Edit: Just read Kev's idea. Similar concept but, where I was creating and using separate reference marks for alignment, he just traced the overlapped part of the previous section of his design to align the next section.

[Kev Williams]

That big plate was done x-axis-swapped to the y axis, so it was done top to bottom- it was 48" x 30", and that machine's working area is only 25 x 19"- only reason I COULD do it was because the gantry uprights are 31" apart, the plate just barely fit, plus I had to remove my straight edges so the plate could be taped to the table, no clamps! Don't remember if I did it in 3 sections or 4 but at least 3 were necessary.

You can map out your moves in Corel so you know exactly how far to move your belt, or mark the table with tape, etc... hard to explain, this isn't much better but might help ;)
453710

[Bert Kemp]

One of my biggest problems is the leather belt stip is over 60"s long I only have about 20"s of space behind the laser and can't move the laser, so taping the belt to a long board is out. Also becausr the belt is so long its going to require a lot of moves. I haven't designed the belt yet so maybe to make things easier, would be to leave a space between sections of the design then when moving the belt It won't have to be exact, if I'm off a hair in the distance moved it shouldn't be a big deal. So maybe just a guide for the leather to move thru will be enough.
I've used two similar approaches for lasering. First time, I needed to engrave a shape that would be cut out later so I just added small squares engraved in waste areas of each "tile" or section. Then, after repositioning the substrate for the next section, I first ran the laser at zero power with the red dot turned on to trace the reference squares in their new position so that I could fine tune positioning as necessary before engraving the next section. That worked but took a lot of fiddling and pucker power.

Second time, I didn't have "waste" areas so used a carrier with notches along the side, thinking that it would be easier to just slide the substrate and carrier until the next notch lined up with an index along a straight edge (the same idea as in the video but I had to use a carrier and created the notches in advance). The flaw was that it was highly dependent on the precision of the notches, and I wasn't precise enough for perfect alignment. Would work great if, for example, you also had a large enough CNC to make the carrier with precision spacing, or if your work piece allowed you to cut the notches along the edge (or, alternatively, cut small holes somewhere in the interior, similar to the CNC in the video) of your substrate on the fly as you engraved each section; you could then align the notches or holes with fixed index pins for each subsequent section.

You could tape your belt onto a long board, which would keep the belt straight, provide a fixed reference side, and (assuming the board was wider than the belt) provide space to create reference marks next to the belt, along the edge of the board, for repositioning.

Edit: Just read Kev's idea. Similar concept but, where I was creating and using separate reference marks for alignment, he just traced the overlapped part of the previous section of his design to align the next section.

[Bert Kemp]

Thanks for all the replies, every one gave me ideas and they all helped. Since this is a belt for me its kinda like a proto type for the next one. Don't know when I'll do it but will let you know how it turs out. Thanks guys

[Glen Monaghan]

I haven't designed the belt yet so maybe to make things easier, would be to leave a space between sections of the design then when moving the belt It won't have to be exact, if I'm off a hair in the distance moved it shouldn't be a big deal. So maybe just a guide for the leather to move thru will be enough.

Oh, well if you don't have to engrave a full-length contiguous design, then Bob's-your-uncle! Just keep your alignment along the length straight and leave sufficient gaps at the places where you need to shift the belt so that a millimeter or so of misalignment in the shift direction isn't obvious.

[Bert Kemp]

LOL Well lets hope Uncle Bob is right LOL :D
Oh, well if you don't have to engrave a full-length contiguous design, then Bob's-your-uncle! Just keep your alignment along the length straight and leave sufficient gaps at the places where you need to shift the belt so that a millimeter or so of misalignment in the shift direction isn't obvious.