Need advice on power needed for CNC Laser machine

Hi everyone.

I am in the process of gathering up parts to build a DIY laser (based on the open source 2.x Laser designed by Barton Dring) and it's a 40 watt Co2 machine. I am building mine slightly larger (from about 20x12 to 24x18 inches cutting area). Given my cabinet is going to be larger I can likely fit a larger tube.

The materials I would mostly be cutting is: Balsa up to 1/2 inch thick, Lite Ply up to 1/4 inch thick, Birch Aircraft ply 1/2 inch thick.

Will a 40 watt tube suffice (man, I hope so)? If not, then what would be adequate, 60 watt? I know the optics (mirrors and lens need to be upgraded) and Power Supply parts will change too.
Is there any downside to going larger beyond cost? Spot size? Kerf width?

Thanks

Bob T.

I have a 40w laser and I would be hard pressed to recommend it for cutting 1/2" aircraft plywood. I do not know about the balsa. The problem is the number of passes it would take to get through the thick material. Balsa, it could probably handle, but the extra passes may char the balsa excessively, I really have no experience with balsa however. lets wait and see what others say about this, as I am not an expert at all.

Milt

hi there
the aircraft plywood is very strong due to the used glue and that's the problem the glue does not cut well. but for 1/2 inch thick plywood you need at least 60W or 80 W laser machine to get ad efficient cut.
greetings
waltfl

1/2 inch your going to need at least 80 watts if not more, 40 watts has a difficult time with 1/4" they will do it but not consistently with a single pass, and double the wattage doesn't mean double the cutting power.it doesn't work that way.

Thanks all. Yes, in my travels all over the internet I've read that it's the glue used that's the number 1 factor in cutting aircraft ply. What was so confusing that I was reading opinions from folks that live in different parts of the world and they all contradicted one another until I realized that the wood ply and glues used here in the USA aren't the same in other parts of the world.
Well, I'm still looking into the 80-90 watt tube instead of the 40 watt. It means I have to build the cabinet larger to accommodate the longer tube. No real big deal except for the stiffness. Have to watch out to keep the frame stiff enough so that I don't have any alignment issues later on.

Why not just add the box to hold the tube like this one.

also theres a pretty big price jump in tubes fro 40 watt to 80 or 90 watt tubes just something to keep in mind, especially if your on a budget.

Quote:

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Originally Posted by fixtureman1

Why not just add the box to hold the tube like this one.

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Yeah, I've thought of that too. It's likely what I'll do because the 80-90 watt, and all the 60 watt I've looked at thus far are 49". The 40 watt is about 43" if memory serves me right. I have a supplier that sources a 80-90 watt tube for $500+ 50 for a shipping crate. VIP Lasers. Sounds almost too good to be true.

Bob T.

Quote:

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Originally Posted by Bigbird48

also theres a pretty big price jump in tubes fro 40 watt to 80 or 90 watt tubes just something to keep in mind, especially if your on a budget.

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See my previous reply. Of course the mirrors and lens and power supply ramp up the cost too. I just hate the idea of having a machine that is so-so and not up to my needs. I think 40 watt's a bit on the iffy side from all the videos and such I've looked at on youtube. It would be fine for balsa sheet goods but marginal for plywood. I'm going through a significant amount of work to build this thing so I don't want to be fussing/modifying it later.

Bob T.

Yea I would say they sound to good to be true, but hey maybe not, check them out real good.