Author Topic: laser. (Read 22000 times)

Tweakie · « **on:** October 08, 2012, 06:57:41 AM »

A CO2 laser produced image on Obeche using the Mach3 Impact / Laser Engraving plugin with a step-over of 0.2mm and feed-rate of 3000mm/min.

Tweakie.

John Stevenson · « **Reply #1 on:** October 08, 2012, 07:44:46 AM »

Do you have her phone number ?

Tweakie · « **Reply #2 on:** October 08, 2012, 08:19:04 AM »

She looks a bit expensive to run John so I gave that a miss.

Tweakie.

John Stevenson · « **Reply #3 on:** October 08, 2012, 02:10:26 PM »

Wonder what it costs to rent ?

krv3000 · « **Reply #4 on:** October 08, 2012, 05:34:54 PM »

thats the wife

Tweakie · « **Reply #5 on:** October 09, 2012, 06:48:05 AM »

This little charmer is just about within my budget.

Tweakie.

kwackers · « **Reply #6 on:** October 09, 2012, 08:16:15 AM »

I've had her, she wasn't that great.

Tweakie · « **Reply #7 on:** October 09, 2012, 08:27:27 AM »

Was that Ashley Olsen or Super Kitty ??

Tweakie.

Lykle · « **Reply #8 on:** December 16, 2012, 11:10:17 AM »

Hi Tweaky,

Looking good! Have you tried it with lettering instead of an image?
How does that come out? I think it might be a bit more difficult to get it right for plain text.

Lykle

Tweakie · « **Reply #9 on:** December 16, 2012, 11:31:53 AM »

Hi Lykle,

Because lasers are essentially a 1 bit device (on / off) engraving text is probably the easiest task of them all.
Both vector and raster engraving are possible and this is just a basic example of some raster work.

Tweakie.

Lykle · « **Reply #10 on:** December 23, 2012, 05:26:22 AM »

Oh wow Tweaky, that looks very good!

Next question, how does that look on Aluminium or Stainless Steel?

And of course, do you have a build log of the device? Because more and more I have a need for engraving, and this is much better than engraving. So I would love to make something like this.
Although stuck out here in the boondocks is not the best place to be to build something like this. But I can try.

Lykle

John Stevenson · « **Reply #11 on:** December 23, 2012, 06:27:27 AM »

Won't work on alumium, very hard to mark without some stuff called Ceemark which is an aerosol that cost £100 a tin [ no typo ]
It contains a ceramic slurry made from ground up 3rd century Ming vases, hence the price.
The laser melts this and fuses it to the surface, it's suitable for most metals.

You can do stainless easily but spraying the surface with some dry moly lube [ £12 a tin from RS - better ] and then laser it into the surface

Screwcutting chart but had problems with distortion [ since fixed ] but this gives you an idea of what it can do.

Next step is to switch the air assist off and try fusing power coat powder onto alloy.

John S.

{edit} Sorry knackered the link up.

Tweakie · « **Reply #12 on:** December 23, 2012, 08:34:32 AM »

As John said, my CO2 laser will not mark aluminium without an additive.
However, it will ablate the dye layer in anodized aluminium as shown on this scrap piece of black anodized.

Tweakie.

Rob.Wilson · « **Reply #13 on:** December 23, 2012, 10:37:25 AM »

Nice job John

Did the heat build up in the plate make the etching go darker (amusing it was etched top left to bottom right) in the bottom right corner ?

Rob

John Stevenson · « **Reply #14 on:** December 23, 2012, 11:33:21 AM »

Rob,
No the job was crap but it proved the concept.
The reason it darker bottom right is the plate warped with the heat and curled up, this then altered the focal length of the beam so you get fatter letters which hold more black.

same at the top as it did all the lines and circles first, then went on to do the lettering. The last lettering to do was at the top and because of the curl it's missed the circles.

Best example is the middle of the plate except the two last lines as I tried to see if it would push down and moved the plate.

When I do them not I pin them to a big block of alloy and do the lettering in stages to allow the heat to dissipate.

Another way of doing these is to take a sheet of normal perspex, spray the back silver using a Willco rattle can, burn the image on the back in reverse, then rattle can it black.

This gives you a nice plate and smooth on the front so the lettering can't wear off.

Rob.Wilson · « **Reply #15 on:** December 23, 2012, 01:05:25 PM »

Makes scene John ,I suppose it would not take much for the beam to be out of focus .

The Perspex chart came out a treat . Did you scan the original chart or did you do it in CAD?

Rob

John Stevenson · « **Reply #16 on:** December 23, 2012, 01:34:17 PM »

Did it in CAD using a couple of photo's and a sketch of the sizes.
The original was too far gone to scan.

DaveH · « **Reply #17 on:** December 23, 2012, 03:07:32 PM »

John,
That perspex one is very nice

DaveH

John Stevenson · « **Reply #18 on:** December 24, 2012, 05:33:55 AM »

Tweakie.
That picture on the anodised alloy is fantastic.
I know it can be done and last week i picked a load of 1mm sheet offcuts that I want to send in to the anodisers to get done.

Can you give us a blow by blow of how it's done as not done any graphics on the laser yet ?

Noitoen · « **Reply #19 on:** December 24, 2012, 08:19:23 AM »

Is your laser engraver home made?

Tweakie · « **Reply #20 on:** December 24, 2012, 11:49:30 AM »

Quote

Can you give us a blow by blow of how it's done as not done any graphics on the laser yet ?

The images were produced using the Impact / Laser plugin with Mach3.
There are more details here; http://hobbymaro.puhasoft.hu/Tweakie/Engraving.pdf
The latest version of the plugin .dll is here; http://hobbymaro.puhasoft.hu/Tweakie/Engraving.dll

Quote

Is your laser engraver home made?

My laser is homebuilt.

Tweakie.

John Stevenson · « **Reply #21 on:** December 24, 2012, 06:43:19 PM »

Tweakie,

Thanks for that but not using mach3 and using the propitiatory software with the Chinese laser

Tweakie · « **Reply #22 on:** December 28, 2012, 03:07:50 AM »

Ahh…Looks like you (and Art) will have to make the best of what the Chinese laser operating software has to offer.

Tweakie.

Tweakie · « **Reply #23 on:** January 03, 2013, 06:40:41 AM »

Many will have already seen a Lithophane or perhaps made their own. It is an ancient art form dating back many centuries and was at it’s most popular, here in the UK, during Victorian times. They were often produced by hand engraving an image in wax on a glass (or similar) sheet then pouring over clay slip. Once dry the parts were separated and the slip incorporated and fired into a porcelain or china clay tile, plate, cup etc. The invention of photography was perhaps the cause of their demise and unfortunately, they eventually fell out of favour and all but disappeared.

The advent of CNC has slowly caused a revival and they are now starting to gain popularity once again. I have made many using spindle machining but wondered if it would be possible to achieve acceptable results using a laser and I was honestly surprised by the results.

I still have to make some improvements in the technique used but thought you may like to see the results so far.

Tweakie.

Tweakie · « **Reply #24 on:** January 12, 2013, 06:40:53 AM »

Hi Guys,

Thanks to suggestions from others I have been able to improve my technique and this is the latest Lithophane laser cut into Corian.
I was using a constant velocity of 4000mm / min for the X axis (excepting the acceleration and deceleration zones for each line scan). The final work does need backlighting (unlike opal Plexiglas) so it looks like I will be making a few LED / diffuser light frames when I get the chance.

Tweakie.

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Author Topic: laser. (Read 22000 times)

Rob.Wilson

Rob.Wilson