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

Help! I need suggestions for FB & Balsa cutter

Dazzy

Active member
#1
Just recently I paid US$15 bucks for a set of plans to build a 3 axis laser 60w cutter that would reliably cut foam, ply, balsa and light aluminum, the only problem that this build comes in at US$2500.00+. Ive been looking into it for a few weeks but just ant justify the $$ right now.

So can anyone suggest an alternative that at least cuts balsa upto 3/8" and foamboard or what I can reliable get here in oz its called depron to 6mm?

Im looking for a cutting size of 750mm square, ie 30" square or thereabouts.
 

Merv

Well-known member
#2
A needle cutter is the most economical way to go for making planes from fb. I’m in the process of building one myself.

I’m no expert but I believe balsa is far easier to cut with a laser than fb. It’s the white foam that is hard to cut, it reflects the laser. I’ve seen claims that some diode lasers can cut balsa. A machine that had interchangeable heads, a needle cutter for fb & a laser for balsa may work.
 
#3
with those plans, you could set the system up for using a Diode laser rather than a CO2 laser. Might save a few bucks on components as you would be able to shrink it all down.
 

jhitesma

Some guy in the desert
Mentor
#4
Diode laser can easily cut thinner balsa...but 3/8" would be tricky. Even with multiple passes you'd probably wind up with enough charring to through off accuracy. 1/8" and thinner no problem. 1/4" I've done with my 3w diode laser...but it's pushing it and you start to get more burning resulting in a larger kerf.

Best bet for best bang for the buck is probably a MPCNC like I built (and has been done by many others and discussed in depth in the needle cutter thread on here.) for foam I love my needle cutter, but I also have the 3w laser I use for thin ply and balsa as well as posterboard, and a router with a 3mm endmill I use for plastic, thicker wood (I've done 1/2" ply and hardwoods). If you build it large enough to do full sheets of foam you'll loose enough rigidity that metal isn't very realistic and you'll have to go slower on things like plastic and hardwood...but I'm not doing this for profit so I'm willing to slow down and take my time.
 

Dazzy

Active member
#5
A needle cutter is the most economical way to go for making planes from fb. I’m in the process of building one myself.

I’m no expert but I believe balsa is far easier to cut with a laser than fb. It’s the white foam that is hard to cut, it reflects the laser. I’ve seen claims that some diode lasers can cut balsa. A machine that had interchangeable heads, a needle cutter for fb & a laser for balsa may work.
In my prev post I put 3/8", that should have been 3/16 balsa".

Hey Merv thankyou for the fast reply, so does a machine with an interchangeable head exist to cut foamboard and light balsa?
 

Dazzy

Active member
#6
Diode laser can easily cut thinner balsa...but 3/8" would be tricky. Even with multiple passes you'd probably wind up with enough charring to through off accuracy. 1/8" and thinner no problem. 1/4" I've done with my 3w diode laser...but it's pushing it and you start to get more burning resulting in a larger kerf.

Best bet for best bang for the buck is probably a MPCNC like I built (and has been done by many others and discussed in depth in the needle cutter thread on here.) for foam I love my needle cutter, but I also have the 3w laser I use for thin ply and balsa as well as posterboard, and a router with a 3mm endmill I use for plastic, thicker wood (I've done 1/2" ply and hardwoods). If you build it large enough to do full sheets of foam you'll loose enough rigidity that metal isn't very realistic and you'll have to go slower on things like plastic and hardwood...but I'm not doing this for profit so I'm willing to slow down and take my time.

Hi Jhitesma like I said to Merv, In my prev post I put 3/8", that should have been 3/16" balsa. Anyway does a diode cutter exist?
or alternately
Has anyone built a multirole cutter that has interchangeable heads that you are aware of?
 

jhitesma

Some guy in the desert
Mentor
#8
3/16" should be possible with a 3w laser and air assist. May just take some experiments to find the optimal power/speed/number of passes to get the cleanest cut but should be possible.

And yes, the MPCNC can use multiple heads. That's how I switch between the 3w laser, the needle cutter, and the router all on the same machine.
 

Dazzy

Active member
#9
3/16" should be possible with a 3w laser and air assist. May just take some experiments to find the optimal power/speed/number of passes to get the cleanest cut but should be possible.

And yes, the MPCNC can use multiple heads. That's how I switch between the 3w laser, the needle cutter, and the router all on the same machine.
Hey jhitesma have you documented any information on your setup at all, maybe in pictures or video as Im sure myself and others would be interested in these features?

I havent found any yet but do you have any threads related to your design?

Further, is there any special preparations required for cutting when changing heads given that Im assuming here there are offset considerations to take into account for different cutters ( just assuming )?

Thankyou for the replies to date. Dazzy.
 

jhitesma

Some guy in the desert
Mentor
#10
I documented a lot of my learning in the giant "Needle Cutter" thread, and have started a few threads of my own on here (Just click on my profile and search for them) about other related projects. I do have a youtube channel where I posted videos of some of it but haven't uploaded anything in over two years. Would like to get back to more video...but just don't have time now that I'm a single father. I know the needle cutter thread is huge and intimidating...but there's a TON of great info in there.

As for swapping heads, the way I work with my machine the changes don't really matter. I keep things "dumb and simple" so instead of messing with offsets in software I usually just manually position the machine to where I want 0 to be (usually the top of my material in the lower left corner) and then reboot it's controller to zero all of the axes. Though I did stat getting a bit fancier when I noticed my machine would sometimes drift out of square with that method. So now I either push it all the way to the lower left corner until it physically stops against block I positioned to square it against and then keep it powered without rebooting from there so the steppers don't loose their position. Or...once I do that I use the LCD controller on my machine to reposition it to where I want home to be and then have a gcode command set as a shortcut in the LCD to re-zero everything.

But there are a lot of different ways to do it. I've also experimented with a GRBL based controller instead and a dedicated computer to feed gcode to it to get a more traditional CNC like experience. But I found for the simple kind of work I usually do it's more hassle than it's worth. The Marlin based setup running gcode off a sdcard is quick, and reliable for 95% of what I've asked my machine to do.