Hi Guys,

After about 7 months collecting the stuff, machining and building, I have finally got my CO2 cutting head up and running. Early days yet as I still have a lot of learning to do but I thought you may be interested in seeing the first test piece. Pretty basic pyro-engraving but as it was the first thing made I am pretty pleased with the result.

I made a short video (low resolution) which is here http://www.cooperman.talktalk.net/laser1a.wmv

If anyone is interested in further details of the CO2 cutting head, the build details are here http://www.cooperman.talktalk.net/files/27.htm

When I manage to lay my hands on some genuine Depron I will let you all know if or how well it cuts.

Tweakie. Attached files

 

That is incredible! Wow!

 

Hi Kram,

I doubt I have the setup to cut right through the MDF but if the carbon residue was gas cleared from the kerf and multipass was used then it may be possible but I think that a much more powerful laser than mine would be necessary.
The video is in real time. If my machine acceleration settings were increased it could have been completed a lot faster (my machine table is on casters standing on an insulated floor and any faster acceleration setting tend to make the machine rock).
Can' take any credit for the GCode - this was posted by Sam on the Mach forum to give us an alternative to the Roadrunner code.

My first tests with Balsa resulted in a fire but I have now fitted an air direction nozzle to the laser lens assembly and this has improved matters considerably. So far just 1/16" sheet but nice cuts (sooty edges) and quick too.

Thank you for the interest, I will post more details as I proceed.

Tweakie.

 

This is the 1/16" balsa cutouts (same GCode I used for the OS engine gaskets).

I have found that lower power settings with lower feedrates seem to work best here but I have a problem with my (import from China) digital current display at low prf settings so my next job will be to replace this with a legacy type moving coil panel meter. This will give me a better idea of the ideal settings to obtain repeatability.

Tweakie. Attached files

 

I'm going to add just a word of caution, you may even know about it. At my work we just purchased a laser die cutter it cuts sheets up to 5 feet square and a 1/4 inch thick. When the tech came to setup the machine they warned against certain material such as Vinyl produce toxic gases. As far as the the gas removal they came back and did a retro fit of a small vacuum it helps with the dis colorization of the material. Any way just wanted to throw that out there

 

Thanks James, you are quite right - the most dangerous thing about laser cutting is the toxic fumes and particles produced.
Although I am running this in a well vented area with an extractor system it would perhaps be a wise precaution to fit an extractor hood above the machine position. Another project to think about.

Tweakie.

 

I'm just curious. Beside the coolness factor, what's the advantage of a laser over a router? I'm sure the cuts can be made clean with a router also.

 

Hi Yoram,

I really don't think there is any advantage, for me it is just another tool.

Adding the laser head has in some respects increased the versatility of my machine ; I can still route wood, plastics, circuit boards etc and engrave with the spindle and I can also fit a vinyl knife for cutting decals, signs etc or an impact engraver for marking hard stuff.
The laser would not be much good for any of these tasks but it does excel at certain things such as fine engraving.
I have yet to discover it's full potential but if it saves the need to manufacture another press tool just for making custom Melanex insulators it will have paid for it's parts cost.

Tweakie.

 

Still experimenting, this is 1/4 balsa and 1/8 acrylic - I chose the same part to get comparison of the results between different materials.

I have been unable to cut lite-ply without setting it alight, I think it is the adhesive used to bond the layers but at least I have learn't the reason why inert gas is used when cutting certain materials

Tweakie. Attached files

 

Hi Mark,

The laser will cut 1/4 balsa in one pass, with the power turned up a bit, but the extra heat generated spoils the straight sides and tends to burn the material. So they were cut in two passes. I will try both the balsa and acrylic again with CO2 gas assist (borrow the bottle from my MIG set) instead of air and see what difference it makes.
I am learning fast but not fast enough I think.

These are 2mm and 6mm acrylic.



Tweakie.