• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

HOME BUILT CO2 LASER FOR DTFB (lots of pics)

#1
I thought I would share a few pictures of the laser build that I completed recently. When I began with flite test planes only a few months ago I knew quickly that I wanted a way to cut out my own planes from the plans that they so generously provide for each of their new releases. I have a CNC router that cuts the foam nicely with a little tiny bit, but it can only cut out a sheet up to 24x24 so the DTFB at 20x30 was a no go. I had been modifying the layout of the plans within auto-cad and Corel to get them to fit the working area of the router but it was a pain. I had a little old lightly used Asian K40 laser laying around so I decided to gut it as a donor for a much larger laser that could cut a full sheet of DTFB. I ended up with a little over 31x21" of travel so I can comfortably fit a full sheet of the foam and use every square inch of it now. I did not have any plans I just designed it in my head as I went. Most of the mechanics are from the original K40, they have just been cut apart and extended quite a bit to get the desired travel. The electronics are from Cohesion3D (amazing improvement over stock) and the software that I use to control it is called LightBurn, again a quantum leap over the corel plugin that the stock K40 relied upon. Now I have full control of laser speed and power on the fly and I can assign different cut or score or engrave strategies to each layer as I see fit. Below are about 35 pics of the build process up to the laser as it sits today. It is all done with the exception of the lifting bed that I need to get finalized, for right now it is just set for the thickness of DTFB but as I want to be able to cut other things or engrave on thicker objects it will ultimately be able to move up and down about 4 or 5 inches. Thanks for looking.
 

jhitesma

Some guy in the desert
Mentor
#8
Very nice. I have my MPCNC with a needle cutter for foam and 3w laser for light duty stuff...but I've really be considering picking up a K40 for some heavier engraving/cutting. The price on them has come down so low it's hard to say no....but it looks like the newer 50w models are <$2k now and have better controllers, ship with air assist, and have a better controller...but they're about $1,000 more and ship in a 2'x2'x4' crate that comes on a truck so you have to pay an extra $150 for lift gate service for home delivery.

So I'm kind of torn...pick up a cheap K40 and then put as much or more money into upgrading it (new electronics, air assist, better power supply...) or pony up the cash and make room for something bigger.

Which is the other issue...not sure where I'd put a laser cutter...my shop is out of room. And while I no longer have to appease my wife my keeping hobby stuff out of the house, I'm not in a big rush to let it in myself now either :D
 
#9
Very nice. I have my MPCNC with a needle cutter for foam and 3w laser for light duty stuff...but I've really be considering picking up a K40 for some heavier engraving/cutting. The price on them has come down so low it's hard to say no....but it looks like the newer 50w models are <$2k now and have better controllers, ship with air assist, and have a better controller...but they're about $1,000 more and ship in a 2'x2'x4' crate that comes on a truck so you have to pay an extra $150 for lift gate service for home delivery.

So I'm kind of torn...pick up a cheap K40 and then put as much or more money into upgrading it (new electronics, air assist, better power supply...) or pony up the cash and make room for something bigger.

Which is the other issue...not sure where I'd put a laser cutter...my shop is out of room. And while I no longer have to appease my wife my keeping hobby stuff out of the house, I'm not in a big rush to let it in myself now either :D
I fully understand the space constraint, and honestly it was no small consideration in my case. As you can likely see I mounted mine under a work bench on ball bearing slides so that I can pull it out into the room when it is in use, and then stow it away when I am not using it. It doesn't quite fit under the bench but almost. I use a laser at work that is physically larger than this one yet has about half of the travel, most of the Chinese, and American lasers seem to have a lot of wasted real estate inside of them that leads to a machine which ends up being much larger than it needs to be.
I think that K40 lasers have dipped below 375 on eBay now, shipping included. Honestly for that price they simply cant be beat as there is no way you could buy even half of the included components for that price. Most if not all K40's even the newer units are hobbled by a controller card and software pair that really limit the usefulness of the laser. In other words the hardware is actually better than the software side of things allows. In my build, as in many others the combo of the Cohesion3d control card and the LightBurn take care of all of those shortcomings for less than 200 bucks. I now have a fully function piece of software that far exceeds the capabilities of the 35K laser that I use at my "real job" This software really makes the laser a joy to run and use. In total I spent right around 1k on this build including the donor K40 but I do have a fairly good supply of raw materials and I am better than average at scrounging as well.
 

jhitesma

Some guy in the desert
Mentor
#10
I fully understand the space constraint, and honestly it was no small consideration in my case. As you can likely see I mounted mine under a work bench on ball bearing slides so that I can pull it out into the room when it is in use, and then stow it away when I am not using it. It doesn't quite fit under the bench but almost. I use a laser at work that is physically larger than this one yet has about half of the travel, most of the Chinese, and American lasers seem to have a lot of wasted real estate inside of them that leads to a machine which ends up being much larger than it needs to be.
Yes, I was very impressed by the under bench mount. Though even the area under my CNC bench is stuffed full...I really need to do another major cleaning of my shop (it was just 2 years ago I emptied it to make room for the CNC and it's already impossible to walk in again!)

One of the big issues is with the CNC I've been building more and now I've got piles of mostly built planes waiting for me to finish them :D

I think that K40 lasers have dipped below 375 on eBay now, shipping included. Honestly for that price they simply cant be beat as there is no way you could buy even half of the included components for that price. Most if not all K40's even the newer units are hobbled by a controller card and software pair that really limit the usefulness of the laser. In other words the hardware is actually better than the software side of things allows. In my build, as in many others the combo of the Cohesion3d control card and the LightBurn take care of all of those shortcomings for less than 200 bucks. I now have a fully function piece of software that far exceeds the capabilities of the 35K laser that I use at my "real job" This software really makes the laser a joy to run and use. In total I spent right around 1k on this build including the donor K40 but I do have a fairly good supply of raw materials and I am better than average at scrounging as well.
Well...I just gave in. eBay is running a 15% off coupon today only. Found an updated K40 (Different controller, wheels, light inside, temp sensor) that came out to $305 shipped with the 15% off. For that price I couldn't say no. Even if i wind up replacing the electronics (not sure what the "upgraded" controller will be) I'm up for it. Same for things like adding air assist and such. Don't think I'll do what you did and enlarge it - I have my CNC for big stuff. I mostly want this for cutting smaller stuff...but who knows what I may decide to do down the road. I planned on looking into lightburn anyway to use with the laser on my CNC....
 

dkj4linux

Well-known member
#12
Oh, Jason... dang you! Never even considered it... but if you're going down that rabbit hole, how the heck are we supposed to keep up?
 

jhitesma

Some guy in the desert
Mentor
#14
Oh, Jason... dang you! Never even considered it... but if you're going down that rabbit hole, how the heck are we supposed to keep up?
Well, the CNC is out in my shop and I don't get out there very often now that I'm the only responsible adult in the house. So I figure a smaller Co2 laser will give me a machine that will fit on my dining room table - but can still be moved out of the way when I want the house presentable :D (I even have an exhaust opening in the laundry room next door - may need a slightly stronger fan and longer hose but seems to be made for it!)

But it looks like I'd have a long way to go to catch up to @nebraskatrevor myself so I wouldn't worry about catching up to me yet ;)

Honestly if it wasn't for the 15% off ebay sale today I wouldn't have pulled the trigger. And I'm still kind of thinking I'd be better off with one of the newer 50w models (even if they're more like $1,500) since they have a bigger working area, 10 more watts, adjustable bed height, better control board, and come pre-fitted with air assist and an air pump. But...I kind of need a project more than another machine and I really don't have anywhere I could fit on of the larger 50w machines right now and $305 shipped is right at the "sounds like a potentially fun project" point :D

Plus my daughter likes the idea of me having a laser. She apparently didn't know I already have one since she's never been allowed in my shop while it's running since I only have one pair of safety glasses. So having an enclosed one she can observe may get her more involved in making things I hope!
 
#15
Well done man, well done!
Nothing beats dropping in a sheet of foamboard and 2 minutes later having a kit ready to assemble does it! (y)(y)
It is satisfying, but it is more like 8 to 11 minutes a sheet depending on the complexity of a sheet. Not as fast as a higher wattage laser would be but still quite satisfying to watch.
 

dkj4linux

Well-known member
#16
Well, the CNC is out in my shop and I don't get out there very often now that I'm the only responsible adult in the house. So I figure a smaller Co2 laser will give me a machine that will fit on my dining room table - but can still be moved out of the way when I want the house presentable :D (I even have an exhaust opening in the laundry room next door - may need a slightly stronger fan and longer hose but seems to be made for it!)

But it looks like I'd have a long way to go to catch up to @nebraskatrevor myself so I wouldn't worry about catching up to me yet ;)

Honestly if it wasn't for the 15% off ebay sale today I wouldn't have pulled the trigger. And I'm still kind of thinking I'd be better off with one of the newer 50w models (even if they're more like $1,500) since they have a bigger working area, 10 more watts, adjustable bed height, better control board, and come pre-fitted with air assist and an air pump. But...I kind of need a project more than another machine and I really don't have anywhere I could fit on of the larger 50w machines right now and $305 shipped is right at the "sounds like a potentially fun project" point :D

Plus my daughter likes the idea of me having a laser. She apparently didn't know I already have one since she's never been allowed in my shop while it's running since I only have one pair of safety glasses. So having an enclosed one she can observe may get her more involved in making things I hope!
I do understand, Jason... just yanking your chain a little bit ;)

Actually, I can always use a new project myself... the price doesn't sound unreasonable, it'd be something new to play with, and you've really got me thinking now. Even though I haven't really finished the projects I've got going now... they are all to the point that it's just the "finishing" lacking. And you know how I hate finishing anything... :eek:

@nebraskatrevor, you've really done some impressive work. Kudos!
 

jhitesma

Some guy in the desert
Mentor
#17
Hey @nebraskatrevor - question for you about the cohesion board.

From what I can see it's basically a clone of a smoothie board - but with external stepper drivers instead of built in. Which seems like a step back to me. One of the big appeals of smoothie to me (aside from being easier to update and being 32bit and faster...) are the built in stepper drivers with the ability to set the current on them through software.

It seems like the upside of the cohesion board is it's footprint matches the K40's board, and they ship with configs already defined for the K40 along with helpful diagrams on how to wire them.

But...I don't mind doing the config myself, and figuring out the wiring isn't that hard having built a few machines from scratch, and footprint doesn't bother me as I can easily make new mounts.

I'm also not a fan of the A4988 drivers that cohesion ships with their boards (though I do have quite a few spare DRV8825's I could swap in which IMHO are far superior) so I'm having a hard time selling myself on cohesion for an upgrade.

My machine should be here today - I have a spare RAMPS (as well as a CNC shield and Uno board) which I could toss in it as an initial upgrade since I'm pretty sure I'll hate the stock control board. But I'm trying to decide what route I'd like to take for a future upgrade. An actual smoothieboard 3x is $40 less than Cohesion's board so that's kind of tempting. And MKS Sbase boards (Chinese clones of Smoothie) are only about $60 which is even more tempting....

I'll probably start a thread of my own about whatever I wind up doing to the cheap K40 I picked up....but wanted to get your feedback about why you chose the Cohesion board to help me make some decisions!
 
#18
Hey @nebraskatrevor - question for you about the cohesion board.

From what I can see it's basically a clone of a smoothie board - but with external stepper drivers instead of built in. Which seems like a step back to me. One of the big appeals of smoothie to me (aside from being easier to update and being 32bit and faster...) are the built in stepper drivers with the ability to set the current on them through software.

It seems like the upside of the cohesion board is it's footprint matches the K40's board, and they ship with configs already defined for the K40 along with helpful diagrams on how to wire them.

But...I don't mind doing the config myself, and figuring out the wiring isn't that hard having built a few machines from scratch, and footprint doesn't bother me as I can easily make new mounts.

I'm also not a fan of the A4988 drivers that cohesion ships with their boards (though I do have quite a few spare DRV8825's I could swap in which IMHO are far superior) so I'm having a hard time selling myself on cohesion for an upgrade.

My machine should be here today - I have a spare RAMPS (as well as a CNC shield and Uno board) which I could toss in it as an initial upgrade since I'm pretty sure I'll hate the stock control board. But I'm trying to decide what route I'd like to take for a future upgrade. An actual smoothieboard 3x is $40 less than Cohesion's board so that's kind of tempting. And MKS Sbase boards (Chinese clones of Smoothie) are only about $60 which is even more tempting....

I'll probably start a thread of my own about whatever I wind up doing to the cheap K40 I picked up....but wanted to get your feedback about why you chose the Cohesion board to help me make some decisions!
I will answer as best I can, but just know up front that I can already tell you know quite a bit more about the electronics side of it than I do! As I see it the cohesion3d has a few advantages, for me at least that made it desirable. First it works directly with the k40 stock electronics, that was a huge plus for me. Next it can run from the software I use, lightburn which btw is the best 40 bucks you will ever spend. Or run off of an sd card. I envision storing repetive jobs on the sd card and just loading them from the screen menus rather than hookimg up the laptop for those. I also like that it is super easy to configure. I just changed sizes and speeds but it was a simple as editing a text file. I cant speak to the other controllers you mention and they may be very similar. For me it came down to it being a nearly drop in solution. I dont know a ton about stepper drivers, but my ear tells me these are great. The steppers finally sound happy after years on the stock card where they sounded terrible. They also run very cool, barely above ambient even when the laser has been running for a while. I should also mention that the knowledge base for the cohesion board is wide and willing to help at a moments notice through their Google group. Good luck with your build!
 
#19
I also forgot the best part. The cohesion is able to manipulate the laser output power at all times. This allows you to draw things on as many diffirent layers as you want and then in the lightburn software you assign a diffirent cutting and or engraving strategy to each of those layers. That is extremely handy when cutting out f.t. style plans since you can have notes, scores, and cuts all on diffirent layers, with each being indivually adjusted. The lightburn/cohesion does this so seamlessly that it is amazing. It can really be appreciated if you had sone time trying to dial in, and then later replicate laser output power on a k40 using the cheap potentiometer that comes with them stock. This method is pardon the pun....light years ahead!
 

jhitesma

Some guy in the desert
Mentor
#20
Ok, that makes a lot of sense. Manipulating the laser output should be possible with just about any board - it's kind of shocking to me that they didn't built it into the initial system since it looks like the board they use should be capable of that.

That said...I got my machine last night and the stock electronics are even worse than I expected! I'll definitely be starting a thread later today about my experiences with the machine and the route I take to improve it.

I do see one nice thing about cohesion now that I have a machine to look at. That ribbon cable connector. That simplifies wiring a lot. But...I do NOT like that ribbon cable at all! They're running current to the X stepper through that?! I mean, the load is super low so there's not much current required - but still....that's just a failure waiting to happen. The Y stepper is run through real wires, but unless they're using 3-4 conductors for each of the 4 wires on the stepper there's no way that ribbon is rated for the current steppers use. So if you're literally looking to just drop in a new board the cohesion does make sense.

The cohesion being the same size is also kind of nice if you're looking for super easy...but...the stock board mounts in mine are questionable - the stock board is bowed because it's holes don't match the mounts! Wow.

There are some nice things I like about the machine compared to others I've seen online...but overall wow are the stock electronics sketchy! I'm leaning heavily towards going with an actual smoothie board right now - same basic guts as a cohesion board...only supported by the team that makes the firmware, and much nicer stepper drivers built in with software current control. Bit more complex to wire...but the stock wiring is iffy enough I don't mind replacing it...in fact I'm looking forward to replacing it :D

I'll start my own thread later so I don't clog this one up.