Hi there Foorum mebers
I´m a newbe on laser cutting…
I have 2 questuons.
#1 Please give me a hint about the space beetwen the wood
and the bottom.
I esume I have to have some metalic plate under.or?
. #2 How do cut if the wood is slightly bend
Kristian
Most often, a steel plate or a honeycomb is used, this has the advantage that you can use magnets to align your material.
When using steel plate, you should ensure that there is space between the material and the steel plate, otherwise condensation may occur.
Hey, I´m new to this forum. I´ve built 2 laser routers from scratch.
regarding #1:
I use ceramic tiles (from my bathhroom renovation) as a flat base on my wooden table. Then I have a 1.5cm thick honeycomb on top of that. You should consider space between the material you want to cut and the bottom, otherwise you´ll get burnmarks on the bottom of your workpiece. I would reccomend honeycomb or similar. Most honeycombs come with an aluminum plate sufficient enough for most diode lasers.
If you buy a honeycomb, it will come with pins like these. Both my aluminum and steel honeycombs came with a set of them. They are $8/100 on Amazon, so no worry if you slice one or two.
I pitched the honeycomb when I found there didn’t seem to be any use to it except to cause fires and mark up the back of the work. It’s worst attribute is it destroys the air flow in my laser. These best thing I did was to pitch the honeycomb.
Steel plate, alignment holes for jigs… easily wipes off. If you’re cutting, you need to raise the material off the plate, where I use 5mm tall magnets. Here is mine doing a job with the stock fan and pump with the door completely open and cutting 5mm sub flooring.
I pitched mine, because it didn’t work as I imagined… and I found most places that seem to have laser fires have honeycomb beds.
Of course that’s my opinion, as a vast amount of users who implement them. Including Russ Sadler who has some videos of how poorly and dangerous these actually prove to be.
@bernd.dk mine was aluminum, so I couldn’t use magnets
I want to pick up the gauntlet one last time.
Jack and I strongly disagree on the meaning and use of honeycomb. That’s perfectly fine and legitimate. But, I “defend” honeycomb not from principle but from experience. (Jack certainly does too )
As my primary use of my CO2 laser, I make lamps in 0.8mm 3 layer plywood. Some parts are relatively fragile and delicate. I cut all parts directly on my steel honeycomb, no intermediate layer. There are sometimes traces of smoke on the edges, but not so much that it is a problem in the production process itself. If some parts need finishing, I use a clean cotton cloth with technical alcohol and wipe off the traces of smoke without any problems.
The lamps that I have made in clear and opal acrylic are also made in the same way, but they have a protective film from the factory on both sides. Here I never post-process.)
Why don’t I have the massive soot traces and condensate that other users of honeycomb have?, or the fire hazard that some users talk about…
I am convinced that the correct air circulation, i.e. the amount and ratio of in and out suction is the key to success. (this can be achieved with strong, adjustable fans/extractors)
If you have the opportunity to obtain the right conditions, a honeycomb machine bed can be used without the risk of fire and with very little soot, I have proven it for over 3 years.
It will simply look too amateurish to have a relatively expensive laser cut product with fire marks for sale, my lamps have absolutely no traces of such fire/soot marks, I guarantee that.
I’m not writing this because I think my point of view is more true than Jack’s, I’m telling about it because I think there are several different options and that honeycomb can be used just fine if used correctly.
I do think you’re right about ventilation, which was the driving factor for me to remove the honeycomb. Air flow would go into the machine and most of it would end up going down the honeycomb, completely avoiding the cut area, which is where I need it to flow.
Different machine configurations will also make a difference, such as my vent being in the rear compared to the sides and at the bottom.
It was only an opinion… I do think I mentioned the fact the many people, including Russ Sadler who knows honeycomb issues well, still uses them.
I cut small pieces and use a hand brush to push them all off the steel plate into a container.
I’ve accumulated a bunch of cardboard sheets to cover the area around whatever I’m cutting, plus a baffle in the front passthrough hatch to keep the incoming air from going below the platform.
So the airflow is through the hatch, over the cardboard, past the material, down through the honeycomb around it, and away.
For big slabs, I remove the honeycomb and use the knife blades underneath.
A few mm is often enough to prevent reflections from the laser hitting the subsurface and back to the workpieces being processed.
A new shiny aluminum honeycomb will reflect more like a black steel honeycomb/steel plate.
As I have written before in my post, I use no spacer material as standard. If I want to use some distance I will use punk spikes, I have them lying around here but use them very rarely.
The images are set up as a demonstration. I have several different tall punk spikes. Sometimes I cut 2mm holes in the 4 corners, it makes centering/positioning easier.
In the case of general plates, which are not wobbled, it is the same height of punk spikes which give it a flat surface. Sometimes weight blocks can be used to force the material down, the weights just need to be smaller in height than one’s focus height to avoid carambola.
An important prerequisite is, of course, that the machine bed is level.
Sorry, I still not understand the way to get the material flat with magnets.
can you make a schematic sketch, so
I understand how it works.
Forgive my stupidity
There is not much to explain, the prerequisite is that your honeycomb is made of black steel and not aluminium.
In addition to magnets, I have also made other “hold downs”, you can see in the pictures.
THX Bernd
that was great info.
How about the hold down with the pin.in pic 3. is the pin same thicknes as
the hole in the honeycomb ?
I found a steelplate (Honeycomb) on Bauhaus here in Gothenburg
is this useful ?
It`s 120X1000X2,2MM
This one has a “spring system” and fits tight in the honeycomb hole, the other which is my faforit and which I use daily, fits loose in the hole but is drilled and glued to an angle to the part that holds the items down. A small press on the end of the top plate and it presses firmly without expanding the Honeycomb hole.
I have described it in an old post and think I have also posted the drawing here, but where …