Thread: DIY Laser Cutter Engraver

and another of Ricks little laser
[ame="http://www.youtube.com/watch?v=CEPjTfP5GNc"]YouTube - Rick Laser Co2 cutting geared CARD[/ame]

I would think speed would be helpful as well, and you don't need a heavy gantry loaded with a heavy spindle motor so this will be a bonus. You may have to go for servo's for speed... I am not being altogether serious here, just stirrin Rod

Cheers.

Russell.

Don't listen to him Sean. This is how your machine will be communicating with your driver - are we there yet - nah we overshot - back up a metre- are we there yet - nah too far - go forward a metre - and so.
Seriously not like that at all but I couldn't let Russell get away with it.

lol good night guys I need some sleep.

Well I have been busy doing up the plans still plenty more to do but its a start I will probably send the plans to Bennets Steel next Monday with the final cut list plenty cutting for them to do.

Anyway this is the skin nearly finished will be welded up as I cant imagine screwing together 25x3 mm SHS but I may go the two Ill get a quote and see what the difference is..

The actual innards will be on something like a 80/20 frame.

Morning all,

Belts what are people thoughts on these and can we get them in Australia they aren't going to have to handle a lot of weight actually very little the axis is going to be 1300 long so I guess that's 2600 long and light weight if possible I need to look up pulleys as well.

Sean

Originally Posted by stevejw

would it be possible to mount the laser to the Z axis vertically on a gantry which is fixed. Then have the X & Y axis move the table so the gantry is fixed.

Your response was that "it would be like waving a fluoro tube around in the air.
How? Why?

If the laser is fixed to an unmoving Z axis, and the table is moved beneath it, then where is the 'waving about' going to come from?

Puzzled,
Andrew

Hi Andrew,

My first thoughts were the same to mount it vertically but when I thought about it there are probably a few reasons worth considering.
The 100w laser tubes are 1800mm long and require water cooling in the tube. There could be problems with flow rates given the lift required in vertical mounting. Depending on the volume of water in the tube there could also be quite a bit of added weight to the glass tube.
If the laser is fixed then the only method of axis movement is a moving table design. This means all three axes will have to be operating under the table which will be very complex.
The machine is operating at high speed so the sudden starts and stops will probably set up a resonance that will cause problems.
If you shed has a roof height of 2400 then that only leaves 600 under the laser tube to make the machine.
All the designs I looked at mount the tube horizontal so I think that is a good indicator that this is the way to go.

Hi Andrew it would be fantastic way of doing it but as Rod said height and resonance could be a real killer and that's what I was trying to say with my post just lost for words these things running well dont run slow at all and a v2 100w 1.8m tube around $900us I cant take that chance.

Also having a moving table that can do 1200x800 would also be impractical because of space and it really needs to be enclosed as well for safety.

Just to give everyone an idea of what a tube looks like I have added a picture its a gas tube inside a another cooling tube that is filled with coolant.

At 1.8m it aint something to be stuffing around with water and electricity don't mix.

A high speed low line gantry is what I need to build .

Sean








.

Moonshine tube

Originally Posted by rodm

Moonshine tube

You calling me a Hillbillie

Thanks I couldn't get the following song out of my head so I though I would share.

[ame=http://www.youtube.com/watch?v=2y9dkCJYB8M]YouTube - Theme Song and Credits to The Beverly Hillbillies[/ame]

When the laser eventually dies it may be the next project make some black gold.

Sean / Rod,
I now understand your design concerns with my suggestion, so if the tube is fixed in horizontal plane how is the beam directed at the ever moving mirror / colminator on Z axis?



Cheers
Steve

Originally Posted by stevejw

Sean / Rod,
I now understand your design concerns with my suggestion, so if the tube is fixed in horizontal plane how is the beam directed at the ever moving mirror / colminator on Z axis?

Cheers
Steve

Hey Steve I am always open to ideas the way this is done is using mirrors, easiest way of showing you this is via a video of a laser being set up

Go to about 5mins in.

[ame="http://www.youtube.com/watch?v=qfIOOxOZ4SQ&feature=related"]YouTube - Laser Engraver Setup Part 2[/ame]

So the Z axis is the work table you can lower or heighten the table as required for the work piece.

You could have an z axis but then you would need another mirror but from what I nave been reading every time you use a mirror you have a % of loss it may be 3% on the first then 9% on the secound then the third in the head more loss add a fourth you get even more loss so what happens is you end up having a tube that may be say a 40w but only is giving you 30w by the time you get past all the reflection etc.

Then you have three mirror types three different coatings range from $17 each up to about $60 for the best grade mirrors these will help with above but you want the best possible result when you spend the $$$$..

Thanks Sean,
The process is now as clear as mud Now i see tha the Z axis can be very light and this will aid in high speed very clever!
I t is actually very simple I am impressed.


Cheers
Steve