Laser cutting/engraving help.

[Glyn Jones]

I have recently bought a 40W laser and have now got it installed and working! I have tried various different materials for cutting and engraving, and have had various degrees of success. I thought I would open a new thread for non-technical Q&A about cutting and etching.
I have various questions, and may be able to offer some help with other peoples problems.
When all my kit arrived the air-assist pump was wired for 110V and as I live in the UK it needs to be 240V. While waiting for a transformer to be delivered I decided to experiment with various materials. Engraving was fine, but I cannot cut through 4mm plywood without it charring badly. Is this because the compressor is not attached, or could it be something else?

[Neil Pritchett]

Hi Glyn,

40W and 4mm ply in a single cut is pushing things a bit!
You don't say what laser you have, all things are not equal when it comes to quoted power ratings.

The air assist will make a big difference as it will do 2 things:
1/ keep the smoke 'fog' away so the beam does not get filtered.
2/ keeps the edges of the cut cooler reducing the burn.

With the air assist, the laser can also cut faster. This will also reduce the edge burn.

Sorry you bought a US machine. I think we could have given you more direct support. We are the distributors of Redsail lasers here in the UK, and we provide on-site warranty for our customers. However, we will always try to help where we can.
Our web site gives some advise and tips. Take a look at ctrlasers.co.uk There may be some hints that will help.

Best regards. Neil

[Glyn Jones]

Thanks Neil,
It will cut through 4mm acrylic in a single pass, and will cut the ply but chars the edges. The laser I bought was a Pinnacle M40. The main reason for buying abroad was the exchange rate. I looked at various lasers in Europe, but they were all considerably more expensive as I wanted a large cutting area. I should get the compressor working this weekend, so I'll keep you posted!

[sloppie]

use low nozzle pressure when cutting acrylic. see if this helps

[Neil Pritchett]

Originally Posted by Glyn Jones Thanks Neil, It will cut through 4mm acrylic in a single pass, and will cut the ply but chars the edges. The laser I bought was a Pinnacle M40. The main reason for buying abroad was the exchange rate. I looked at various lasers in Europe, but they were all considerably more expensive as I wanted a large cutting area. I should get the compressor working this weekend, so I'll keep you posted!

Hi Glyn,
The air assist is vital for ply.
You will also find that the quality of the ply makes a big difference. As a giude, the tighter the grain, the less burning. It appears to be that the end grain of the plys "burns back" when these are soft and/or loose grained. The tighter grain of birch ply has less tendancy for this to happen. Also Beech is an excelent wood. This is because there is virtually no difference between the summer and winter growth, both are tight grained.
Hope this helps. Regards. Neil (for http://www.ctrlasers.co.uk)

[dragoneye]

Hello Glyn,

When cutting ply use interior ply and you wont have a problem cutting 6mm it all in the glue that is used look for A bonded Ply birch ply is the one used in the states which is made in russia if you cannot find it in the uk use the best you can find it will pay in the long run, your have trouble with acrylic if you dont cut all the way through in one pass as it will heal itself i cut 9mm ply and 15mm acrylic in one pass on a 60 watt laser, and can cut 6mm on my 40 watt laser make sure you take great care in mirror alighment as this will reduce the cutting power. just a note make sure you only cut cast acrylic as the other gives off bad odour and smokes badly mdf gives off a poisoness gas when it is cut so make sure you have a good filter system set up for this .

Hope this is of use to you

Trevor