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Cutting foam sheets... with a needle!

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wait so for these kits, you still need to 3dprint the pieces? also, does it include the electronics, or is it in the kit?
I assume this kit will be the same as the original and does not includes the printed parts or aluminum extrusions. But all printed parts are relatively simple flat parts that are quick and easy to print... and the V-slot extrusions are available from multiple sources. Everything else is included in the kit... including the electronics.
 
I'd suggest getting onto the ERC FB group (and peruse the FT thread) to see what others -- without a printer -- are doing. I'm sure this isn't an uncommon problem.

If you are an avid DIY'er, a 3d printer is IMO the single most valuable tool in your toolbox... and well worth looking into getting. Beyond my earliest machines, I couldn't have done any of the machines/mechanisms I've done in this thread without one. Please note also that though Edward has made a monumental effort to document his machine and provide step-by-step direction to build it... it is still a DIY project, i.e. not so much a traditional "kit" as a collection of all the parts necessary to build/duplicate his machine.
 
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Anti-Gravity Foam Wing Cutter Controller

Hi All

Probably not the place to post this (it's the only thread I know with intelligent folks in it :) ), but for now, I'll put it here to see if there's any interest - if so, I'll do up some schematics and stuff and move it to where it might need to be .

It's been a while since I visited this thread and much has happened since. I didn't completely waste my current lockdown .
This is a quick show of what is in essence, an electronic emulation of a gravity drop-arm foam cutter (similar to the old Tekoa style of arm).
The original cutters had a weighted drop arm calculated in percent - to which were attached cables/clips and a multitude of pulleys and wheels.
There was much 'faffing' about swapping cables over when you had finished doing one wing then swapping to the other - this just has a button.

This IS NOT a CNC controller - more a kind of mandraulic controller  I haven't seen anything like this around, otherwise I would have made one - let me know if this is the case !

I've attached a couple of pix and a link to an amateurish video to show the operation. The metre stick in the video emulates what would be the hotwire bow with a foam block to be cut in front of it (tip set at 75% chord of the root) - there would be aerofoil templates either side of the block for the hotwire to ride on of course.
The controller is an arduino nano with a couple of A4988 stepper controllers - a few pots and pushbuttons - plus the ubiquitous 3D printed enclosures and parts of course  Motors are just a pair of nema17's I had lying around (as with the rest of the parts really). Version 1 used geared motors (el cheapo  ) - worked perfectly except that at slow speeds, the motors had too much stiction and occasionally stopped. I tried various cheap motors - all the same really. A pair of ultra expensive swiss geared maxxon motors worked perfectly of course :mad:
Version 2 is what you see here.
Control is simple, setup you motors/cords across the width of the foam block, set the basic hotwire speed then dial in the (pre-calculated) ratio of the root to the tip (root is always 100%), switch on the hotwire and hit start. Wait until it exits exactly parallel to the trailing edge, then hit stop. Rinse and repeat for the bottom template. For the opposite wing, same thing, setup your hotwire again, press the swap button (swaps root/tip speeds) then hit start again.
Root to tip ratios are not as simple they sound, there are MANY other things to take into consideration ! I wrote an app around 20 years ago to do this very job and it's still just as valid today (I had a set of plans for an agricultural mechanical version of this controller on my old website back then). It was written in RealBasic (nee Xbasic) - it's now called Xojo (why???) I have the code repaired in the latest version, but no longer own a licence - it can compile to mac/pc/web/android/ios etc these days. You can run it in the IDE (it's free to do anything, just can't compile sans a licence) - if you have a licence, that might be useful to the community .

Let me know if there is any interest in this project.

Cheers

Neil

Link for video ...

 

Attachments

Anti-Gravity Foam Wing Cutter Controller

Hi All

Probably not the place to post this (it's the only thread I know with intelligent folks in it :) ), but for now, I'll put it here to see if there's any interest - if so, I'll do up some schematics and stuff and move it to where it might need to be .

It's been a while since I visited this thread and much has happened since. I didn't completely waste my current lockdown .
This is a quick show of what is in essence, an electronic emulation of a gravity drop-arm foam cutter (similar to the old Tekoa style of arm).
The original cutters had a weighted drop arm calculated in percent - to which were attached cables/clips and a multitude of pulleys and wheels.
There was much 'faffing' about swapping cables over when you had finished doing one wing then swapping to the other - this just has a button.

This IS NOT a CNC controller - more a kind of mandraulic controller  I haven't seen anything like this around, otherwise I would have made one - let me know if this is the case !

I've attached a couple of pix and a link to an amateurish video to show the operation. The metre stick in the video emulates what would be the hotwire bow with a foam block to be cut in front of it (tip set at 75% chord of the root) - there would be aerofoil templates either side of the block for the hotwire to ride on of course.
The controller is an arduino nano with a couple of A4988 stepper controllers - a few pots and pushbuttons - plus the ubiquitous 3D printed enclosures and parts of course  Motors are just a pair of nema17's I had lying around (as with the rest of the parts really). Version 1 used geared motors (el cheapo  ) - worked perfectly except that at slow speeds, the motors had too much stiction and occasionally stopped. I tried various cheap motors - all the same really. A pair of ultra expensive swiss geared maxxon motors worked perfectly of course :mad:
Version 2 is what you see here.
Control is simple, setup you motors/cords across the width of the foam block, set the basic hotwire speed then dial in the (pre-calculated) ratio of the root to the tip (root is always 100%), switch on the hotwire and hit start. Wait until it exits exactly parallel to the trailing edge, then hit stop. Rinse and repeat for the bottom template. For the opposite wing, same thing, setup your hotwire again, press the swap button (swaps root/tip speeds) then hit start again.
Root to tip ratios are not as simple they sound, there are MANY other things to take into consideration ! I wrote an app around 20 years ago to do this very job and it's still just as valid today (I had a set of plans for an agricultural mechanical version of this controller on my old website back then). It was written in RealBasic (nee Xbasic) - it's now called Xojo (why???) I have the code repaired in the latest version, but no longer own a licence - it can compile to mac/pc/web/android/ios etc these days. You can run it in the IDE (it's free to do anything, just can't compile sans a licence) - if you have a licence, that might be useful to the community .

Let me know if there is any interest in this project.

Cheers

Neil

Link for video ...

what is that even for?
 
most led lasers will not cut the white foamboard, it will cut the top paper layer and that's about it. The white foam just disperses the laser. Black foamboard with black foam core cuts fine on my 7.5 watt output neje laser. This are my findings, other may vary.