Hi All,
Mainly for @AngusMcleod but useful to document anyway.
Wanted to know how well 1/4" and 1/8" balsa wood cut using the 2.8W JTech laser on the X-Carve. Spoiler alert: actually very well 
First off the 1/8" sheet I got. It is this one:
I did the classic laser at 25mm above the surface, 0.2mm step down each pass and 15 passes (emulating a spindle). Usual 1.6amps power (about 2W).
Cleanly cut at 500mm/min which I thought might be pushing it. Kept increasing feed speed until the test square (30mm X 30mm with rounded corners) no longer cleanly fell out on lifting the material. That was at 2300mm/min and 2500mm/min required some pressure.
So safe speed for cutting is 2000mm/min which is about five times faster than I thought it would be. This gives a little bit of over cutting that ensures a clean cut.
Cheers
Ian
4 Likes
Then tried the 1/4" sheet, this one:
This time I did the test square with 30 passes but with the laser at 75mm above the surface and no step downs. This avoids the laser beam being clipped due to the beam divergence.
Again a very clean cut at 2000mm/min at the same power.
Works really well, just under 2minutes run time.
Cheers
Ian
2 Likes
In the 1/8" material banged out a quick 100mm X 50mm battery tray. Total cut time just over 9 minutes.
Cheers
Ian
1 Like
Looking at the sacrificial waste board underneath I think we can increase the DOC to say around 0.4mm, possibly halving the number of passes, depending on your scheme (actual step down or not).
Cheers
Ian
Fair bit longer than I would have expected for a laser, but that’s a darn nice-looking finished product.
Is there a thread on here with your conversion, and what all this is? Very interested in ALL of it, and how to do it.
I think it could be done quicker but the point of this was a clean and perfect cut first. Optimisation of feeds and speeds is left to the user
You are welcome Angus, not really played with balsa before so interesting for me anyway.
I’d agree. If you can cut it with a spindle then do that. If you can’t then the laser is doable but for small runs.
I’m currently playing with combining the two in carbon fibre/fibreglass (I’m into big hex/octocopters). Cut using the spindle then laser on markings all in one job with a rough (cut) and detail (laser). It’s just down to getting the offset between spindle and laser bang on.
That could work for you. Spindle cut the majority but laser those inside corners you need to be sharp.
Cheers
Ian
Fair 'nuff! It’s really not a fair comparison anyway, I’ve just been watching tons of videos of ~30-50W CO2 lasers, so my mind is turning up images of single passes cutting the stuff like butter. Utterly unfair, given the absurd price difference, but it skewed my expectations a bit. lol
Just bought a Cheap Chinese 40 watt Laser delivered to my door for $366.00!
It is limited to about an 8 x 11 inch cut area. I also own a JTech laser for my X-Carve which is used more for engraving large areas. Working on making a portable version of just the JTech for working on an unlimited size surface.
Totally agree. If I needed to do laser cutting (because a spindle cannot) everyday with lots and lots of work I’d also buy a proper 40w machine and a software package to suit.
The JTech to me is simply another little cutting/marking “bit” which has actually turned out to be a lot more useful than originally thought when I got it. It combined with the X-Carve has added a huge new dimension to my wife’s jewellery business.
Always a balance between cost, speed, usability, life span etc.
Cheers
Ian
What are the main differences between the JTech and Chinese 40W? I’m currently decided between the two.
39.2 watts. Sorry couldn’t help myself.
But it is power. A 40 watt will be a dedicated machine, JTech is a laser diode add on.
Dave
Ariel, WA
What types of things would each laser do best with?
The JTech will attach to the carriage of an X-Carve and can be used for laser engraving and cutting thin materials.
A 40 watt stand alone laser will also do laser engraving and will cut thicker materials. A 40 watt unit uses water cooling to keep the temp of the CO2 laser tube from over heating. The 40 watt unit is a flying mirror style laser with a fixed CO2 laser tube and mirrors that aim the light on the work as the carriage moves.
It takes a lot more time to aim the mirrors in order to get the best work from the unit.
The JTech unit is a diode laser with no mirrors. The laser unit travels on the carriage and just need to have focus set.
Dave
Ariel, WA
If I’m more interested in cutting materials and not engraving, will the 40W laser do well with quality and accuracy/precision compared to the JTech? Thanks!
What materials and thickness do you want to cut. What is the max size of material you want to cut.
There are a lot of lasers out there for sale. They range from around $300 to as much as you want to spend. They will cut from paper to 1" thick steel and if you want to cut steel you are talking big bucks and a fiber optic laser.
They come is sizes from 12"X12" to 12’X12’ and larger price goes up with size.
Dave
Ariel, WA
Take a look at the Glowforge site to see what a 40w laser can do.
@DavidSohlstrom Do you know anyone Who might know if a 10Watt laser can cut 1/8 baltic Birch plywood? I have some coming in that’s supposed to be laser grade, but am having trouble getting a straight answer? Because regular plywood it’s having trouble, now does it make a difference if it’s old plywood? Main question though can a diode laser cut 1/8 baltic Birch plywood? That’s the main question I’m looking for a answer. Thanks 
Bruce
cutting 1/8 baltic birch plywood would be a very slow process if it could even be done. I believe that most lasers that can cut are generally 30 watt or greater.
Dave
