[MrMaxP]

Hi all,

I'm new to this whole world of CNC lasers so forgive me for asking stupid questions.

I've just ordered a cheap Chinese laser from eBay (the 40W cheap one. K40's I believe most people call them). I know they've generally got a bad rep, but I'm just a hobbyist and don't have much money. I've done my research and I'm happy with the awful software it comes with and the possibility of having to repair it a lot. Fingers crossed it'll work well and arrive without damage.

My main question is sourcing materials to use it with. I'm planning on making various things out of wood and pretty coloured acrylic but where do I buy these things? I'm guessing when it says it cuts ply-wood it means any type of ply? But why do I see adverts for "laser-ply". Is it different in some way? Also, with acrylic, it seems like the prices vary immensely. One company selling A4 sheets for £1 others for £6. And can it cut all acrylics? I'm having trouble finding the answers with google and cnczone searches. Maybe my search skills need improving.

So, can anyone tell me if I need special ply and special acrylic or will anything do? Even better, can anyone suggest a supplier of these in the UK that are cheap?

Thanks,
Max

[ELaser]

where in the UK? if in the south west I can offer some help

[MrMaxP]

I'm in the Birmingham area, unfortunately.

[3Dingo]

Hello MrMaxP

We have the same laser cutter. JL-K3020 - I also have the upgraded laser cutter version as well. We mainly cut acrylic. We have had some problems with some materials. Mainly acrylic sheets that have paper protective layering instead of plastic protectant causing the acrylic to catch fire and damage some components of the laser cutter. Our last fire in our JL-K2030 melted the rail wheels and destroyed the belt. So make sure you never leave your laser cutter cutting un supervised. Proper ventilation and interior blower slims that % of chance of fire quite a bit. Since the fire we are now using acrylic sheets with plastic protective coating the fire stopped during cutting.

We purchase our acrylic sheets from a wide variety of places: (Mainly Amazon and Ebay) here is a list of places we have ordered acrylic sheets through:

https://www.inventables.com/technologies/
Red Translucent Acrylic Plexiglass Sheet 1 8" x 12" x 12" 2157 | eBay
http://www.ebay.com/itm/BLACK-ACRYLI.../271430446035?

the Plastic film acrylic sheets are a bit more expensive but well worth it compared to burning out your laser cutter.

NOTE: some of these have paper protective film please be careful and watch closely while cutting.

Home Depot also has some Clear acrylic sheets but no colored ones.

[MrMaxP]

Excellent, thanks. I've just ordered some ply and a sheet of acrylic off eBay.

My machine turned up today but unfortunately it's broken. Smashed laser tube to name the worse problem with it. Now to argue with the seller about return shipping!

Thanks,

[3Dingo]

Oh man that's a bummer! Same thing happened to us last week our first laser cutter was being repaired by me and my wife ordered another laser cutter and we just got it in at the beginning of the week and same issue BLOWN TUBE!!! So we complained and complained nothing happened so we left very bad feedback and now the seller responds "please send us 30$ so we can ship you a new tube"..took awhile for them to ship but we should be getting the new tube in today and I'll need to research on how to swap out the tubes. I'll keep you posted with the event when I install the new tube.

Your very welcome and I'll put as much info as I can regarding the tube swap.

[3Dingo]

Just found this video showing how to replace the tube. Seems pretty easy and straight forward. Truthfully i think bothering the seller for a new tube seems more reasonable than reboxing everything back up and resending the entire laser cutter back. Just a personal opinion.

[GWKlaser]

very bad purchase experience....

[miketola]

This is good place. They have birch and poplar plywoods.

https://www.kitronik.co.uk/3201-3mm-...0mm-sheet.html

Another places.

It depends what glue they use. "wrong" glue and its just burn black and smell.

/MIKA


https://www.kitronik.co.uk/3201-3mm-...0mm-sheet.html

[MrMaxP]

[QUOTE=3Dingo;1669688]Just found this video showing how to replace the tube. Seems pretty easy and straight forward. Truthfully i think bothering the seller for a new tube seems more reasonable than reboxing everything back up and resending the entire laser cutter back. Just a personal opinion.

Hey, thanks. They have just offered me a new tube. I'm a bit concerned though that the X axis is damaged. The bar that the head moves along is not level with the cutting bed. It seems to be at an angle. From the videos I've watched It looks like this is not supposed to be this way. I've tried to take a couple of pictures. Luckily I very carefully unboxed it and it is now all boxed up read to go back. I'm going to insist on a new machine I think because of the X axis problem.

Attachment 273136
Attachment 273138

[Nolan Yang]

Hello Max, this is Nolan from Thunder Laser, I hope my advice can help you.
laser cutting machine can cut many kinds of materials, like wood, acrylic, paper, plastic, rubber and so on.
but if you use low power laser tube, you only can cut thin materials. more details, please download the parameter for different materials from our website. (nuts)
download - Thunderlaser

[miketola]

MRMaxP. Loose your belts and just put it straight like 90 degrees angle. Its very popular problem in china machines. You can hear small noise when belt is jumping when you turn it right.

[3Dingo]

i installed the tube today with no issues. Same as the video. Anyways regarding the X-axis. I had the same problem the moment i tuned mine on with the new tube today there was a problem with the X-axis uneven and the under chassis belt was very loose on the x-axis. so i took off the rail on the left then i can adjust the Y Axis belt position to align the X axis back to a aligned position. i had to adjust the mirrors a tad but got it working within 30 mins.

[MrMaxP]

Yep, miketola and 3Dingo were right. When I started taking it apart it was obvious that the left and right of the X axis weren't inline! Thanks! It seems to work well now, apart from no laser of course! I taped a pen to it to test it. The tape didn't hold well so the lines were sloppy, but it proved it worked.

Thanks guys.

Attachment 273310
Attachment 273312

[MrMaxP]

I got the replacement tube last night, and thanks to the video I got it fitted and it seems to work fine. I've only done very basic alignment just to test it but it's cutting well. I hope to align it in a couple of weeks when I'm back from vacation and experiment with what it will cut.

New and old tube

[dave92]

Hi There,

I'm new here and have just purchased a K40 laser machine (i had researched these machines prior to purchase so i was aware of what to expect).

My machine turned up with a broken tube but i have been sent a whole new machine, but that's beside the point!

My main question is what speeds and cutting power (mA) are people using for the following materials:

3mm Birch Ply
3mm MDF
3mm Acrylic
6mm Acrylic

I'm struggling to find a happy medium between speed and power.

Thanks in anticipation.