PDA

View Full Version : Very happy with my k40, have some questions !



josh kruse
12-03-2013, 4:58 PM
hi everyone, i am new here. i just received my Chinese k40 40w laser cutter in the mail. i finally got the lenses all aligned and figured out the basics on it.


so far i have removed the bed and made a larger one, i am also working on an adjustable mod. while it is not the best machine, it gets the job done and im happy with it ($575). when i first tried cutting cardboard it wouldn't cut, only burn. i then realized it wasn't at the correct focal length. so that is now fixed. i tried cutting 1/8 inch poplar wood last night on a setting of 12ma. it took about 10 passes before it cut through it but it came out very chard. so...

1, what is the optimal strategy for cutting wood of 1/8 inch (no air assist yet, is this affecting cut time/burn?) ??my machine has the capability for changing cut speed through moshidraw.

2. what type of cheap air assist can i use? a aquarium pump? any ideas?

3. what is the highest i can safely turn the power up to. can i turn it all the way to 30ma on the gauge?

4. for cutting, should i use multiple passes of high speed/ low speed with low power to reduce char? or is there a better route?

5. any free graphic software out there that exports in correct formats to use with moshi? coreldraw is 130 bucks and i would rather try something free.

6. can i keep my laser cutter in my garage? i live in illinois and temps go below zero. i am concerned about the tube. i think it might crack from the heat when turned on. so i was thinking about running warm water through it before use or heating with a heating blanket so the glass doesn't crack.

sorry for all the question. i have lurked for a while here and know there's some very knowledgeable people here that can help me. thanks everyone.

josh

Walt Langhans
12-03-2013, 5:34 PM
Hi Josh welcome to the wonderful world of lasers!

I'll answer what I can for you and let others fill in the rest.

Regarding your air supply, NEVER go cheap here. The more air (most of the time) the better. You need it to keep the area being lasered free of debris and to keep flair ups down so you don't set your stuff on fire.

Here's a good air pump to use: http://www.rabbitlaserusa.com/WebShop/index.html

I keep my laser in the garage, I'm in Atlanta GA and we've hit freezing weather here, but not for any extended periods of time, the only thing I've done is add some anti freeze to the liquid in my chiller and I have not had any problems. HOWEVER, laser tubes have operating specs and I suggest you read up on them. And there are several members in the great white north that should be able to give you further pointers on operating in such extreme conditions.

Good luck and have fun!

josh kruse
12-03-2013, 5:39 PM
so add anti freeze to the water so it doesn't freeze in the tubes? and i need to stay cheap with this machine. im thinking using a tire inflation or pancake air compressor. thanks. hope some more can answer the rest.

acgtaully, i have a big air comprssor in my garage, what type of tubing and connectors would i need to step it down small enough to fit into the machine

Jerome Stanek
12-03-2013, 6:32 PM
I have a heated horse pail and keep the water pump going. the water pump keeps the water abovr freezing and the heated pail is just a backup when it gets real cold.

josh kruse
12-03-2013, 6:43 PM
is it possible to put some anti freeze in the water and drain all water after each use by attachning a air compressor and blowing the water out?

josh kruse
12-04-2013, 1:30 AM
bump need help guys

Jerome Stanek
12-04-2013, 5:55 AM
I was told not to add anti freeze to the water so that is why I looked at the other options. One was to tent the machine and use a light bulb under it to keep it from freezing but when I saw that the water pump was keeping the water at 50 degrees when it was in the low 40s I decided the heated pail and leaving the pump run was what I would do. When it gets real cold I throw a shipping blanket over it and the whole machine stays nice and warm

Dave Sheldrake
12-04-2013, 6:12 AM
1, what is the optimal strategy for cutting wood of 1/8 inch (no air assist yet, is this affecting cut time/burn?) ??my machine has the capability for changing cut speed through moshidraw.

With no air assist you run the risk of damaging the lens on that type of machine, it should cut 1/8th plywood without any real problems though.


2. what type of cheap air assist can i use? a aquarium pump? any ideas?

Hilea ACO280 or larger air pump will do the job.


3. what is the highest i can safely turn the power up to. can i turn it all the way to 30ma on the gauge?

Anything much above 16mA will kill the tube very quickly, above 20mA will cause stability / saturation problems.


4. for cutting, should i use multiple passes of high speed/ low speed with low power to reduce char? or is there a better route?

It can work but tends to be inefficient, air assist will solve most charring problems.


5. any free graphic software out there that exports in correct formats to use with moshi? coreldraw is 130 bucks and i would rather try something free

Inkscape for pictures and Draftsite for DXF cad files. Both free for personal use.


6. can i keep my laser cutter in my garage? i live in illinois and temps go below zero. i am concerned about the tube. i think it might crack from the heat when turned on. so i was thinking about running warm water through it before use or heating with a heating blanket so the glass doesn't crack.

Bubbles are the biggest killer of DC tubes, better to have a additive such as "LS LaserCool" or similar in the water, it runs to -15 degrees safely and has an algae inhibitor. DON'T blow air through the tube unless you really must, they aren't designed to take any pressure and will turn into a glass grenade if something goes wrong.

best wishes

Dave