Cutting foam sheets... with a needle!
- Thread starter dkj4linux
- Start date
That is true. At -30 F I am not sure I want a hole in a wall that will leak in that "refreshing" air into my work space.
Vacuum hold down V2 coming along well. Almost done cutting channels into my base. Need to cut the vertical channels, mill out the hole in the middle for the vacuum, 3d print the adaptor/mount I made for it, then seal it and glue on my pink foam on top. Then drill 150 holes into the pink foam of course.
I also picked up some 1/32" 4mm cut depth bits to try those for cutting plans. Not much thicker than the needle 0.79mm vs 0.63mm. Not sure how well they will work yet and how much of a mess it will leave the top of the sheet.
I also picked up some 1/32" 4mm cut depth bits to try those for cutting plans. Not much thicker than the needle 0.79mm vs 0.63mm. Not sure how well they will work yet and how much of a mess it will leave the top of the sheet.
ironkane
Member
Looks like my setup. I used blue masking tape to seal the edges of a paper stripped sheet of DTFB. I then poked small holes through to the board below. I wouldn't worry too much about making it air tight. I think that these shop vacs prefer some air flow via leakage to run a little cooler. We're shooting for suction, not a true vacuum.
When I said paper stripped sheet of DTFB, I was being literal. Strip the paper off of both sides of your waste board foam. You'll get a better seal for the DTFB you put on top.
When I said paper stripped sheet of DTFB, I was being literal. Strip the paper off of both sides of your waste board foam. You'll get a better seal for the DTFB you put on top.
dkj4linux
Elite member
You really need to give us some more information... and pictures are always welcome.
What "computer" are you using? Firmware? CNC? Cutter?
More info about all these would help us to know a bit about what you've got and where you are with it.
-- David
dkj4linux
Elite member
A month or so ago, after more than 2 years of total inactivity, my needle-cutter/foam-cutting thread over on RCGroups (here) cranked up a bit and showed some signs of life. I began interacting with a couple of fellows, interested in the needle cutter, but who were also fellow Linux enthusiasts. Both are experienced in CNC stuff and running LinuxCNC on a few of their machines.
While all the needle cutter discussion was very good and thought-provoking, I also found my interest in LinuxCNC/EMC2 rekindled. I've shown my BuildYourCNC-inspired, leadscrew-driven, wooden CNC many times but, of particular interest, it also ran LinuxCNC/EMC2... and this was, of course, before there was ever an MPCNC to discover and play with. This machine has sat idle and unused, for several years now, on an enclosed, but non-climate controlled, back porch over in my other house.
And then late last summer, in the August/September time frame and a couple of hundred posts back in this thread, I built my version of "moebeast"s FoamRipper machine, very-loosely based on the LowRider concept from V1Engineering, and somewhat similar in form (moving-gantry) and function (needle-cutting) to the old wooden machine that cut so many RC foamy airplanes for my late fishing/flying/golfing buddy and me.
So, with my renewed interest in LinuxCNC, I decided to see if I could convert the FoamRipper from Marlin-based to LinuxCNC... to try and duplicate the functionality and operation of that old wooden machine I remember with such fondness.
First, I rescued the computer and interface board from my wooden CNC machine... and, of course, it wouldn't boot... or even power on. I replaced the power supply and got the computer to power up but the HDD sadly never responded to my "gentle-then-not-so-gentle" attempts to get it functional again. No biggie, I grabbed another junker HDD -- this one greeted me with a Win2000 BSOD -- and an old LinuxCNC/EMC2 liveCD... and I had a clean install in short order.
Then the parallel interface board, a perfectly good HobbyCNC 3-axis stepper driver board I'd built as a kit... but sadly only suitable for UNIPOLAR stepper motors. As the FoamRipper is driven by NEMA 17 bipolar motors -- ala MPCNC, LowRider, etc -- the old interface board wouldn't do.
So I started thinking that with "step and direction" control from LinuxCNC and also for our beloved A4988/DRV8825 "stepstick" devices... a "marriage" was in order. I scrounged around in my "stash" and found a "Mach3 Interface Board" (a simple and very inexpensive parallel port breakout board)... and a couple of small Uno-compatible CNC shields popular with the GRBL crowd. A few days of tinkering and a small handful of jumpers... and I had an inexpensive parallel-port board-set for LinuxCNC (and probably Mach3) to MPCNC/LowRider/FoamRipper/etc. I've documented this over on the V1Engineering and RCGroups forums and you can follow it in greater detail there... Inexpensive LinuxCNC interface for MPCNC and Mostly Printed CNC and cutting foam.
For those who aren't familiar with LinuxCNC... LinuxCNC is running on a Linux OS with a real-time kernel, on dedicated PC hardware, and is spewing out *real-time* control signals for the CNC machine through the parallel port... no command buffering, ala Marlin/GRBL. There’s no firmware or “smarts” (no Uno!) in this interface circuitry... it is simply conditioning the control signals from the parallel port to drive signals for the bipolar stepper motors. For those unhappy that USB is "not supported"... please understand that USB is historically not fast enough for the required data rates and precise timing for CNC.
PLEASE understand I am not trying to pit one controller software against another or talk anyone into converting their own beloved Marlin-/GRBL-based machines. This is NOT FOR EVERYBODY. If you're just curious and unsure of what LinuxCNC brings to the party… you may want to pass. But if you really, REALLY wants to set up a LinuxCNC system and are willing to put forth the effort and turn over a few rocks, then I'm here to tell you that it's doable and all the necessary bits/pieces are out there... and rather inexpensively, at that.
I'm still in the middle of the FoamRipper/LinuxCNC conversion but, so far, I've used this little board set to drive a small GRBL-based engraving machine...
and a Marlin-based MPCNC...
I've got several threads going, spread over 3 different forums, and am unclear at this point as to how/where I want to document the different facets (FoamRipper, parallel-port interface circuitry, vacuum pad, needle-cutter, etc.) of this project... but I did want to update this thread, which has been languishing for a while. I would hate to see this thread, which has garnered quite a following over the past couple of years, go too long relatively inactive... so feel the need to at least get it caught up to the present.
More to come later.
-- David
While all the needle cutter discussion was very good and thought-provoking, I also found my interest in LinuxCNC/EMC2 rekindled. I've shown my BuildYourCNC-inspired, leadscrew-driven, wooden CNC many times but, of particular interest, it also ran LinuxCNC/EMC2... and this was, of course, before there was ever an MPCNC to discover and play with. This machine has sat idle and unused, for several years now, on an enclosed, but non-climate controlled, back porch over in my other house.
And then late last summer, in the August/September time frame and a couple of hundred posts back in this thread, I built my version of "moebeast"s FoamRipper machine, very-loosely based on the LowRider concept from V1Engineering, and somewhat similar in form (moving-gantry) and function (needle-cutting) to the old wooden machine that cut so many RC foamy airplanes for my late fishing/flying/golfing buddy and me.
So, with my renewed interest in LinuxCNC, I decided to see if I could convert the FoamRipper from Marlin-based to LinuxCNC... to try and duplicate the functionality and operation of that old wooden machine I remember with such fondness.
First, I rescued the computer and interface board from my wooden CNC machine... and, of course, it wouldn't boot... or even power on. I replaced the power supply and got the computer to power up but the HDD sadly never responded to my "gentle-then-not-so-gentle" attempts to get it functional again. No biggie, I grabbed another junker HDD -- this one greeted me with a Win2000 BSOD -- and an old LinuxCNC/EMC2 liveCD... and I had a clean install in short order.
Then the parallel interface board, a perfectly good HobbyCNC 3-axis stepper driver board I'd built as a kit... but sadly only suitable for UNIPOLAR stepper motors. As the FoamRipper is driven by NEMA 17 bipolar motors -- ala MPCNC, LowRider, etc -- the old interface board wouldn't do.
So I started thinking that with "step and direction" control from LinuxCNC and also for our beloved A4988/DRV8825 "stepstick" devices... a "marriage" was in order. I scrounged around in my "stash" and found a "Mach3 Interface Board" (a simple and very inexpensive parallel port breakout board)... and a couple of small Uno-compatible CNC shields popular with the GRBL crowd. A few days of tinkering and a small handful of jumpers... and I had an inexpensive parallel-port board-set for LinuxCNC (and probably Mach3) to MPCNC/LowRider/FoamRipper/etc. I've documented this over on the V1Engineering and RCGroups forums and you can follow it in greater detail there... Inexpensive LinuxCNC interface for MPCNC and Mostly Printed CNC and cutting foam.
For those who aren't familiar with LinuxCNC... LinuxCNC is running on a Linux OS with a real-time kernel, on dedicated PC hardware, and is spewing out *real-time* control signals for the CNC machine through the parallel port... no command buffering, ala Marlin/GRBL. There’s no firmware or “smarts” (no Uno!) in this interface circuitry... it is simply conditioning the control signals from the parallel port to drive signals for the bipolar stepper motors. For those unhappy that USB is "not supported"... please understand that USB is historically not fast enough for the required data rates and precise timing for CNC.
PLEASE understand I am not trying to pit one controller software against another or talk anyone into converting their own beloved Marlin-/GRBL-based machines. This is NOT FOR EVERYBODY. If you're just curious and unsure of what LinuxCNC brings to the party… you may want to pass. But if you really, REALLY wants to set up a LinuxCNC system and are willing to put forth the effort and turn over a few rocks, then I'm here to tell you that it's doable and all the necessary bits/pieces are out there... and rather inexpensively, at that.
I'm still in the middle of the FoamRipper/LinuxCNC conversion but, so far, I've used this little board set to drive a small GRBL-based engraving machine...
and a Marlin-based MPCNC...
I've got several threads going, spread over 3 different forums, and am unclear at this point as to how/where I want to document the different facets (FoamRipper, parallel-port interface circuitry, vacuum pad, needle-cutter, etc.) of this project... but I did want to update this thread, which has been languishing for a while. I would hate to see this thread, which has garnered quite a following over the past couple of years, go too long relatively inactive... so feel the need to at least get it caught up to the present.
More to come later.
-- David
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dkj4linux
Elite member
I might add that I also did a bit of playing around while I had the MPCNC set up with LinuxCNC. I adjusted the LinuxCNC max velocity and acceleration values to match the MPCNC/Marlin values we commonly use. Definite improvement in the movement, more consistent with movement in Marlin-driven MPCNC, with sharper corners... note especially the "M" in the lower plot (before adjustment) in contrast to the upper two plots (after adjustment)
I also decided to see what would happen if I tried to load Allted's obligatory "crown" gcode (Marlin) file -- without alteration of any kind -- into LinuxCNC. My thinking was that the Marlin gcode "pallet" should be a subset of the fuller implementation of LinuxCNC's. Aside from a couple of "warnings" -- not "errors" -- about file termination, they were easily dismissed and the file ran to completion anyway...
-- David
I also decided to see what would happen if I tried to load Allted's obligatory "crown" gcode (Marlin) file -- without alteration of any kind -- into LinuxCNC. My thinking was that the Marlin gcode "pallet" should be a subset of the fuller implementation of LinuxCNC's. Aside from a couple of "warnings" -- not "errors" -- about file termination, they were easily dismissed and the file ran to completion anyway...
-- David
dkj4linux
Elite member
Alright! Finished putting the parallel interface board set together and installed it onto the gantry endplate, where previously the Mega/RAMPS had been.
I am really impressed with the design of these little Uno CNC shields. All the pins for external connections are neatly grouped together and the hookup of that 4th "A" device is very versatile. With just a couple of jumpers, the "A" device can be used as a clone of the X, Y, or Z axis... or used for a 4th axis.
For FoamRipper, I've got 2 motors driving the gantry along the length of the work surface... and the other two are single motors. So I cloned A to Y (as marked on the shield)... and then hooked up the X step and dir signals from the breakout board to this axis, where I now have two motor connections. Then Y step and dir from breakout board went to X (as marked on shield) and, finally, Z to Z; i..e. I've swapped X and Y (as marked on the shield) to simplify the wiring for the two-motor X axis. The two jumpers just above the blue screw connections cloned the A device to Y (not populated yet)... and these two right-most devices are my new X axis. I've also setup DRV8825 1:16 micro-stepping rather than 1:32... just for grins. A dab of hot-glue holds the boards (hopefully securely!) to the standoffs on the mounting plate.
Installed on the gantry end-plate. BTW the USB cable is simply supplying +5v logic power to the interface... no data.
Yeah, it's bulky... but it can be broken down pretty easily/quickly and sized to cut full-size foam sheets of interest to most RC'ers...
and first moves! Air-milling the EMC2 logo from precious tests...
I'm quite pleased with my morning's work. Time for a nap...
-- David
I am really impressed with the design of these little Uno CNC shields. All the pins for external connections are neatly grouped together and the hookup of that 4th "A" device is very versatile. With just a couple of jumpers, the "A" device can be used as a clone of the X, Y, or Z axis... or used for a 4th axis.
For FoamRipper, I've got 2 motors driving the gantry along the length of the work surface... and the other two are single motors. So I cloned A to Y (as marked on the shield)... and then hooked up the X step and dir signals from the breakout board to this axis, where I now have two motor connections. Then Y step and dir from breakout board went to X (as marked on shield) and, finally, Z to Z; i..e. I've swapped X and Y (as marked on the shield) to simplify the wiring for the two-motor X axis. The two jumpers just above the blue screw connections cloned the A device to Y (not populated yet)... and these two right-most devices are my new X axis. I've also setup DRV8825 1:16 micro-stepping rather than 1:32... just for grins. A dab of hot-glue holds the boards (hopefully securely!) to the standoffs on the mounting plate.
Installed on the gantry end-plate. BTW the USB cable is simply supplying +5v logic power to the interface... no data.
Yeah, it's bulky... but it can be broken down pretty easily/quickly and sized to cut full-size foam sheets of interest to most RC'ers...
and first moves! Air-milling the EMC2 logo from precious tests...
I'm quite pleased with my morning's work. Time for a nap...
-- David
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dkj4linux
Elite member
Getting closer....
Set up a FoamRipper configuration. Loaded a SVG file I'd created using the Blackstripes extensions into Estlcam and created a gcocde (.ngc) file. Not too bad for a ballpoint pen... though there are a couple of small ink blobs I wish weren't there. Took a little less than an hour to print.
-- David
Set up a FoamRipper configuration. Loaded a SVG file I'd created using the Blackstripes extensions into Estlcam and created a gcocde (.ngc) file. Not too bad for a ballpoint pen... though there are a couple of small ink blobs I wish weren't there. Took a little less than an hour to print.
-- David
dkj4linux
Elite member
Ok... time to move on. I know folks in the forums I frequent are getting tired of me showing these machines in operation... doing everything but needle-cutting foam. But there is a method to my madness...
Several have mentioned that it would really be of great utility and interest if we could do artwork/linework/decoration on a plane's parts prior to cutting it out using the needle-cutter. Shouldn't be a problem as far as the machine is concerned... but finding appropriate software to accomplish it might be.
Here, I've used Inkscape to create an outlined hatched-circle pattern, shown below. I've used the Eggbot extension to cross-hatch the inner circle -- representing an arbitrary "filled" area -- and moved it to it's own layer... this is the "artwork" to be done with pen or marker. The outer circle is the "outline" to be done with the needle cutter... and is moved to it's own layer. Not sure at this point how valuable this "layering" will be but it seems like a good idea to me.
So I saved the SVG (contains both layers) and then imported it into Estlcam (which I think ignores the layers). There I selected all the artwork to be "engraved" with the "pen" tool and created a gcode file for "artwork". I then deleted all the "artwork" toolpaths... and selected the outer circle to be engraved with the "needle" tool. After previewing to insure just the outer circle would be engraved, I then saved the gcode file for "outline".
My machine currently mounts both a needle-cutter and a pen-holder... the offsets between the two will be determined later. But for now -- for quiet/quick/compact and less wasteful reasons -- I'm using paper and pen (rather than foam and needle cutter) for both the artwork and outline runs. The procedure should not change.
So, I placed a clean sheet of paper/foam on the work-surface and moved the pen/marker into a starting position over the material... setting this location as X and Y "home". I then lowered Z to find the top of the material and set this as Z "home". IMPORTANT: I then manually pressed on the pen (this could be automated I suppose) to insure a small mark was made on the material surface... this is for registration purposes for the next operation. I then ran the gcode for "artwork".
Upon completion of the "artwork" step(s), I ran the pen out over to a random area and UN-homed the machine... losing all origin information. I then jogged the pen back into the vicinity of the registration mark and then "sneaked up" on it, first in X and Y, and finally Z. Setting the "jog rate" slider on the Axis interface to a low value and using the keyboard made this quite easy to align the pen tip (needle tip) with the registration mark.
and, finally, run the "outline"/cutting operation
Carefully done, this should yield "good enough" registration between the "artwork" and "outline" operations... for all but the most "picky" of us
So, that's the plan... as I see it now. I think identifying software and generating the artwork... with dark lines and filled areas suitable for CNC... may well be the "hard" part.
Thoughts? Ideas?
-- David
Several have mentioned that it would really be of great utility and interest if we could do artwork/linework/decoration on a plane's parts prior to cutting it out using the needle-cutter. Shouldn't be a problem as far as the machine is concerned... but finding appropriate software to accomplish it might be.
Here, I've used Inkscape to create an outlined hatched-circle pattern, shown below. I've used the Eggbot extension to cross-hatch the inner circle -- representing an arbitrary "filled" area -- and moved it to it's own layer... this is the "artwork" to be done with pen or marker. The outer circle is the "outline" to be done with the needle cutter... and is moved to it's own layer. Not sure at this point how valuable this "layering" will be but it seems like a good idea to me.
So I saved the SVG (contains both layers) and then imported it into Estlcam (which I think ignores the layers). There I selected all the artwork to be "engraved" with the "pen" tool and created a gcode file for "artwork". I then deleted all the "artwork" toolpaths... and selected the outer circle to be engraved with the "needle" tool. After previewing to insure just the outer circle would be engraved, I then saved the gcode file for "outline".
My machine currently mounts both a needle-cutter and a pen-holder... the offsets between the two will be determined later. But for now -- for quiet/quick/compact and less wasteful reasons -- I'm using paper and pen (rather than foam and needle cutter) for both the artwork and outline runs. The procedure should not change.
So, I placed a clean sheet of paper/foam on the work-surface and moved the pen/marker into a starting position over the material... setting this location as X and Y "home". I then lowered Z to find the top of the material and set this as Z "home". IMPORTANT: I then manually pressed on the pen (this could be automated I suppose) to insure a small mark was made on the material surface... this is for registration purposes for the next operation. I then ran the gcode for "artwork".
Upon completion of the "artwork" step(s), I ran the pen out over to a random area and UN-homed the machine... losing all origin information. I then jogged the pen back into the vicinity of the registration mark and then "sneaked up" on it, first in X and Y, and finally Z. Setting the "jog rate" slider on the Axis interface to a low value and using the keyboard made this quite easy to align the pen tip (needle tip) with the registration mark.
and, finally, run the "outline"/cutting operation
Carefully done, this should yield "good enough" registration between the "artwork" and "outline" operations... for all but the most "picky" of us
So, that's the plan... as I see it now. I think identifying software and generating the artwork... with dark lines and filled areas suitable for CNC... may well be the "hard" part.
Thoughts? Ideas?
-- David
dkj4linux
Elite member
Decided I'd better check the calibration before going too much further...
Not terrible... there's a bit better consistency in the 1mm spacing between tic marks in X than Y. Not sure the cause...
Also there's just a very small error over the 100mm range... I think it is the "Scale" adjustment in LinuxCNC that will dial in the steps per mm?
-- David
Not terrible... there's a bit better consistency in the 1mm spacing between tic marks in X than Y. Not sure the cause...
Also there's just a very small error over the 100mm range... I think it is the "Scale" adjustment in LinuxCNC that will dial in the steps per mm?
-- David
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Michael9865
Elite member
Does your area have maker spaces? Some of them have 3D printers. Also check with your local library.
dkj4linux
Elite member
synjin,
There are no patterns, to my knowledge, for the needle-cutter... other than a few 3d-printed ones, such as Jhitesma's Improved Needle Cutter out on Thingiverse.
The needle cutter is strictly a DIY project. Your post indicates you are a "Compulsive DIYer"... so this should be right up your alley. This thread is teeming with scores of needle-cutter builds and, even without patterns, there's plenty of information sprinkled throughout to, hopefully, give you a few rough dimensions and a sense of direction.
I know this is a long thread but it is worth the read... or at least a scan. Look back at post #1952... my first needle cutters were re-purposed CPU fans, then brushed DC motors on wooden platforms, and brushless motor setups on mouse-traps, laser-cut plywood, 3d printed, etc. There have been metal ones, wooden ones, plastic ones... and cutters built with a combination of materials. The idea is to use whatever materials and components you might have on hand, or are readily available to you, and that you are comfortable working with... using whatever tools and abilities you have.
I'm really not trying to discourage you. I am trying to let you know that this is a very straight-forward build, using common everyday materials, and is well within the capabilities of almost anyone who's a little bit "handy". And this forum is full of friendly folks who have built and use them... and are ready, willing, and able to help you build your own.
So, join in and tell us a little about yourself and your foam-cutting plans... and give us an idea of what you'd like your needle-cutter to look like. We're here to help.
Welcome to the party!
-- David
There are no patterns, to my knowledge, for the needle-cutter... other than a few 3d-printed ones, such as Jhitesma's Improved Needle Cutter out on Thingiverse.
The needle cutter is strictly a DIY project. Your post indicates you are a "Compulsive DIYer"... so this should be right up your alley. This thread is teeming with scores of needle-cutter builds and, even without patterns, there's plenty of information sprinkled throughout to, hopefully, give you a few rough dimensions and a sense of direction.
I know this is a long thread but it is worth the read... or at least a scan. Look back at post #1952... my first needle cutters were re-purposed CPU fans, then brushed DC motors on wooden platforms, and brushless motor setups on mouse-traps, laser-cut plywood, 3d printed, etc. There have been metal ones, wooden ones, plastic ones... and cutters built with a combination of materials. The idea is to use whatever materials and components you might have on hand, or are readily available to you, and that you are comfortable working with... using whatever tools and abilities you have.
I'm really not trying to discourage you. I am trying to let you know that this is a very straight-forward build, using common everyday materials, and is well within the capabilities of almost anyone who's a little bit "handy". And this forum is full of friendly folks who have built and use them... and are ready, willing, and able to help you build your own.
So, join in and tell us a little about yourself and your foam-cutting plans... and give us an idea of what you'd like your needle-cutter to look like. We're here to help.
Welcome to the party!
-- David
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