Richard Rumancik
01-04-2008, 4:37 PM
In another thread Bob said:
Tell me, can you "cut" with a 20 watt laser and if so, how much lumber?
I wanted to make some steelrule dies. ( 3/4" plywood)
Maybe it's smarter to run the lser straight at em. Bob
Bob – thought we should start a new thread so we don't hijack the other one . . .
Making steel rule dies was one on the first applications of C02 lasers in industry. But you probably need a kilowatt+ laser to cut through the birch plywood that is normally used. It is often 15 laminations or so, and the glue really attenuates the beam.
To get a uniform width cut all the way through, you need a long focal length so you don't get a V-shaped cut. As a result you need quite a bit of power.
That being said, I did make a steel rule dieboard as a test with my 30 watt laser. The way I did this was to laminate several pieces of 4 mm birch plywood. I was designing for a 2pt rule (.028 thick steel) so I cut two offset lines to get the width correct to accept the rule. Then I cut 5 identical pieces. With a 40 watt laser you might be able to do it with 3 layers.
Now, the trick is to get them aligned exactly. In the layout I had added alignment holes in the corners. Theoretically two pins are adequate. For my sample, I applied wood glue and then pressed in .156" dowel pins to align the layers together. It is important to keep glue out of the slots. It is actually fairly quick once you do a few. It might be necessary to spend a few minutes cleaning out the slot with a suitable tool to "dress" it to the right tolerance.
Then you need to bend and install the rules.
I don't know if you can compete with commercial die makers, however, with this method. Commercial steel rule dies are generally not that expensive. (Simple shapes maybe $100 ruled.) But if you want to experiment for your own products or in-house work, and can bend the rules, it may be viable. I had the idea that I could supply dieboards to a local gasket company, but they wanted to have complete dies. I am not set up to bend and install the rules. There may be a market somewhere for blank dieboards . . .
The laser has the advantage over a jigsaw when doing multiple dies of the same shape. With the laser, you know they will be the same. When hand cut on a jigsaw, each die will come out a little differently.
Tell me, can you "cut" with a 20 watt laser and if so, how much lumber?
I wanted to make some steelrule dies. ( 3/4" plywood)
Maybe it's smarter to run the lser straight at em. Bob
Bob – thought we should start a new thread so we don't hijack the other one . . .
Making steel rule dies was one on the first applications of C02 lasers in industry. But you probably need a kilowatt+ laser to cut through the birch plywood that is normally used. It is often 15 laminations or so, and the glue really attenuates the beam.
To get a uniform width cut all the way through, you need a long focal length so you don't get a V-shaped cut. As a result you need quite a bit of power.
That being said, I did make a steel rule dieboard as a test with my 30 watt laser. The way I did this was to laminate several pieces of 4 mm birch plywood. I was designing for a 2pt rule (.028 thick steel) so I cut two offset lines to get the width correct to accept the rule. Then I cut 5 identical pieces. With a 40 watt laser you might be able to do it with 3 layers.
Now, the trick is to get them aligned exactly. In the layout I had added alignment holes in the corners. Theoretically two pins are adequate. For my sample, I applied wood glue and then pressed in .156" dowel pins to align the layers together. It is important to keep glue out of the slots. It is actually fairly quick once you do a few. It might be necessary to spend a few minutes cleaning out the slot with a suitable tool to "dress" it to the right tolerance.
Then you need to bend and install the rules.
I don't know if you can compete with commercial die makers, however, with this method. Commercial steel rule dies are generally not that expensive. (Simple shapes maybe $100 ruled.) But if you want to experiment for your own products or in-house work, and can bend the rules, it may be viable. I had the idea that I could supply dieboards to a local gasket company, but they wanted to have complete dies. I am not set up to bend and install the rules. There may be a market somewhere for blank dieboards . . .
The laser has the advantage over a jigsaw when doing multiple dies of the same shape. With the laser, you know they will be the same. When hand cut on a jigsaw, each die will come out a little differently.