RE: [CAD_CAM_EDM_DRO] Keling - Laser Cutting/Engraving Machine

>
> I'm interested in buying a small inexpensive laser cutting machine.
> Inexpensive is relative!
>
> Those I have been looking at are on eBay. Many are sold by Chinese
> sellers with a few sold by sellers in the US. The machines appear to
> all be the same unit and roughly the same price when all is said and
> done. Keling is one of the sellers and has the best feedback.
>
> Has anyone done business with Keling and if so how was their customer

service?

>
> Has anyone purchased one of these little laser cutters on eBay

Yep.

Go get one, they're good fun.

Dunno about Keling, I got mine from
http://myworld.ebay.com/qiandingzhensatisfaction/. They're also known under
a couple of other names (HappyLoveShopping, I think, etc)

They're all the same unit, although there are 3 versions. First is the
'base' unit like you linked to, next up has a few nice bits added, like a
light in the cabinet, air assist etc but the main feature is a Z-lift table.
It's pretty easy to make one yourself, and add the other bits. Those units
are easily spotted by the emergency button in the front panel. Last is
those imported by locals and upgraded with a new driver. (The drivers can
be purchased, but run to $500-$600, so yeah...). Mechanically they're the
same.

These will run straight out the box; hook up the water pump, install the
software and you're set.

That said, mine arrived broken, the large & heavy HT transformer snapped off
its base and bounced around pounding the rest of the board. Seller sent a
new one, in the meantime I repaired the old one (mainly cracked tracks on
the PCB), it still didn't work.

Actually it did, when the new board turned up it didn't work either, I found
the tube was cracked... so the seller sent me a new one.

New tube arrived wrapped in foam & bubble wrap, wedged into a 100mm PVC
pipe, and then wrapping in a few more layers of foam & bubble & tape. It
was an impressive sight. The postman hates me (too many huge parcels) but
even he was amused. Hooked it up, stuffed about with aligning mirrors and I
was finally in business.

That said, the second one was perfect; up & running in an hour.

Hence the seller recommendation, yeah it was broken but they sorted it out
without much hassle. Arrived in under a week too.

The software (MoshiDraw) is terrible, it's recently been update with a new
version - MoshiDraw 2012 which is somewhat less terrible. You don't need to
use MoshiDraw much, do your design in Coreldraw or whatever, and just use
MoshiDraw to cut it. The old version would only import .plt files (HPLG),
the latest will recognise DXF. It used to have a macro where you could
'print' directly from CorelDraw, but I think it only worked up to X3, and I
don't think MoshiDraw 2012 supports it.

MoshiDraw 2012 supports layers which is nice so you can organise the cutting
order better, rather than the 'cut at random' it usually does. I haven't
played with that though.

(As an aside, MoshiDraw 2012 bears a remarkable resemblance to CorelDraw...)
The old MoshiDraw requires XP SP3, the newer one works on Win7. Some claim
the old version works on Win7, I couldn't get it to run.

I'm eventually going to convert mine run on Mach3, so essentially pull the
control board and add a couple driver boards and a BOB. The current driver
seems to run the motor at 24v 0.5A, though the motors appear to be capable
of ~1.7A. Higher amps plus microstepping should improve performance, indeed
one YouTube video claims 700 IPM speed (!). The current max speed is 120
IPM. There's a fair bit on info on the webs about this.

It'll cut wood & plastic, but not metals (steel starts at around 100W +
oxygen air assist, aluminium laughs at you, copper wets its pants from the
hilarity). 3mm MDF cuts at about 10mm/s (too lazy to calc IPM, sorry),
acrylic a bit less depending if you want a nice edge. It's amazingly handy
to use the laser to cut router templates from MDF. Paper, cardstock,
(laminated as well) cuts nicely.

Cooling is needed, mine (like many) is the ultra-sophisticated "pump in a
bucket" model. The tube needs to be kept at 20-24C (room temperature-ish),
I find dropping a 2L bottle full of ice into it keeps the temperature under
control. Going under 20C is ok, hitting 30C is bad.

Commercial chillers are about $500; I was going to rig up a Peltier but
decided I didn't like the idea of needing 100W of heat to produce (at best)
10W of cool, so I've got a tiny bar fridge (42L) I'm going to use instead.
I'm also going to swap the submersible pump for one that isn't, having the
pump dump 10-15W of heat into water I'm trying to keep cool doesn't seem all
that smart.

Here's a few pictures of cutting vinyl stickers:
https://www.dropbox.com/sh/c8zwzxbf5utb9jk/277UqqZoY5. (Ok, it's the end
result.)

That's two layers of vinyl, blue over white. The laser power is adjusted to
cut either just the top blue layer (lettering), both layers (the inside
circle) or both layers and the backing (outside). I was surprised this
worked, btw. I had done one layer (regular stickers) but didn't think two
would work.

Cutting vinyl isn't recommended, it produces gasses that are bad for you
health and rusts your laser something fierce. Even pits the aluminium
parts. (Technically, vaporising the vinyl produces fluorine, that combines
with water in the atmosphere to make hydrochloric acid - enjoy!)

Keep your fingers out of it too, getting shot bloody hurts, even at low
power. Even reflected off the base hurts. Regular clear safety glasses
work for blocking infrared beams, you don't need special $100 ones. And a
spray bottle for putting out the fires.

Still, go get one!

Oh, one more thing. Get an ultrasonic cleaner for the mirrors & lens. I
found cleaning by hand (acetone mainly) looked like it did the job, but
there must have been a clear film that the ultrasonic cleaner removed.
Power levels went up! YMMV depending on what you cut. Plus there's less
chance of scratching, they're pretty fragile. The cleaner was just one of
the cheap $30 ones, nothing special, I use water and a drop of detergent.
Air assist will keep the lens clean as well.

Tony

(That's a rather long post, but lasers really are awesome!)