[rfresh737]

Success today! I finally got my Benbox DIY 2.5 watt Laser machine to actually cut 3mm Plywood!!


This system is sold as an engraver only. I changed a jumper on the controller board and flashed a new gitHub Laser Branch of the Grbl software to make it also work as a laser cutting machine.


This is the unit:
Page Not Found - Aliexpress.com



It is also sold on many other websites such as Banggood.com.

[electronrancher]

Cool, congrats. I wanted to mention that if you are cutting near the upper limit of your machine it is often helpful to set the lens a bit closer to the work than normal. The object is to set the focal point of the beam about mid-way through the material you're cutting.

This might get you a more consistent cut through of your plywood.

Wish you the best of luck!

[duewy]

Isn't it best to drop the Z axis into the cut a bit for each pass thus keeping the optimal distance to the surface of each conservative cut?

[rfresh737]

It would be nice to do that...unfortunately, almost all laser machines don't have a Z axis.

[Bigbird48]

How many passes and how long did it take to cut that sq

It would be nice to do that...unfortunately, almost all laser machines don't have a Z axis.

[rfresh737]

Once I determined the speed for the 3mm plywood (I was powering up at 100%), it took 5 passes and about 20 secs per pass.

[joelaw]

Now that you have it working, can you tell me exactly what you had to change to get it to cut? I have a 3 watt laser and cannot get thru the first layer of 1/16" plywood. It just burns about a .010" deep and then starts burning sideways.

I am using a Shapeoko 3 with a 445nm 3.5 watt laser and a G-2 lens but even with that amount of power it just won't cut.

I also have a lower power Banggood machine and I know that it will not cut. Been working on this for days without success.

Joe Lawrence

[rfresh737]

@Joe,

3.5 watts should be plenty to make 3mm plywood cuts.

I started a thread on your question and asked you some questions myself...please go to this link to read my response to your question Having Trouble Cutting Using 3.5 Watt Laser. Please create a free account and then answer my questions I left there for you. There are also other resources on the Benbox Laser DIY Machines - Index support forum that can help you.

For information on how I did the cuts, look here DIY Laser Machine vs AliExpress

For information on how I modified my Benbox DIY Laser with its 2.5 watt laser to support PWM so I could control and set varying power levels, look here Benbox Interface Questions and go to page [2] and look specifically at Reply #26.

Thanks...

[joelaw]

refresh737:

I signed in and tried to post an answer but I keep getting "403 Forbidden" error or sometimes a "timeout error"?

I will answer your questions here.


1. Yes I can change my laser output with M3 S0 to M3 S255..

2. I focus by eye using a M3 S50 setting and get the dot as small as possible..

3. I just start the program over 6-8 times.

Joe

[rfresh737]

Yeah, I got that 403 error a couple of times this morning too. I clicked the back button and tried again and it finally accepted my post. First time I've seen that.

S50 is too much power for focusing. Try S10 or S15.

What software are you using?

Did you write your gcode test file?

Have you tried using the gcode file I posted on Benbox Laser DIY Machines - Index ? That one makes all the passes in one gcode file so you don't have to restart your 'program' for each pass.

And please tell me again what machine is this?

[joelaw]

Yeah, I got that 403 error a couple of times this morning too. I clicked the back button and tried again and it finally accepted my post. First time I've seen that.

S50 is too much power for focusing. Try S10 or S15.

What software are you using?

Did you write your gcode test file?

Have you tried using the gcode file I posted on Benbox Laser DIY Machines - Index ? That one makes all the passes in one gcode file so you don't have to restart your 'program' for each pass.

And please tell me again what machine is this?

I am using a Shapeoko 3 machine with a Analog laser controller from online with a max of 3 amps, a 12v power supply and Grbl v. 0.9.h I believe. I modified Grbl to set the spindle from 0 - 255 instead of the 30,000 default for output to laser module. It accepts S0 to S255 for a 0 - 5v analog out. I also use Grbl-Panel as control software and M3 turn the laser on and M5 to stop.

I use whatever low power setting so it is bright enough to see well but not burn the board. I have a amp meter in series with the laser output so I can adjust max power to the diode if required. In low power the meter does not move.

[rfresh737]

Hmmm...it does sound like your laser isn't running at 100% power...but you have an amp meter so you know its running at full power (right?)...but what amp equals full power? Normally voltage determines the power...send 5v and you'll get 100% power...send 2.5v and you'll get 50% power. But I don't know what that is in amps...can you somehow check the laser voltage and make sure you're getting 5v? You'll need 5v to do any kind of cutting.

[joelaw]

Sorry I have been gone for many hours. I measure 2.4 amps @ 4.9v going to the diode. Pretty much the max settings for safety. I burned several $100 lasers before getting a GOOD controller.

[rfresh737]

That voltage is OK alright...wow what a head scratcher. If you wouldn't mind trying to post your results on the Benbox Laser DIY Machines - Index forum, @Zax will see it and he may have some other idea's for you...he's pretty sharp...!!!

[joelaw]

refresh737

The Benbox site is still down as of Saturday morning. Still waiting to post.

Joe

[rfresh737]

No, it's been up...I've been on it posting and answering threads: Benbox Laser DIY Machines - Index

[joelaw]

I just tried again @ 6:15 pm EST and I get an error message "This webpage not available" same as before. I rebooted and same thing. I have Verizon FIOS 75mbit, a Dell i7 and don't have problems getting on anywhere else. Maybe it's just me.

Joe

[rfresh737]

Yeah it's something to do with your connection...folks are posting there today and I am posting there too...sorry for the troubles...

[joelaw]

It must be Verizon because I cannot get on with my iPhone, iPad or a iMac? Must be blocking for some reason.