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Jun 15, 2019, 09:00 AM
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dkj4linux's Avatar
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Thanks, DK (I was actually called "DK" when in the Navy, way back when...), for bringing up the power on sequence... it's probably safest to do exactly as they say

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I had hoped the "extra" 2-axis controller board would have the original firmware on it... but he's reflashed it already.

Springer, I found this link to your 3-axis board and it mentions, as a footnote, the software (Grbl and Benbox) is available -- with your order -- upon request...

https://www.aliexpress.com/item/32594280608.html

I'm pretty sure the Grbl and Eleksmaker controller board is pretty stock... but the Benbox software is not open and easy to work with IMHO. I really feel as though I'm flying blind a bit, here. I've built a number of Grbl machines (Shapeoko, Eleksmaker, HobbyKing 3-axis mill, etc) but have always used a separate CAM and freely downloadable gcode sender programs, such as UGS, GrblController, RepetierHost, Pronterface, etc. Here's the same Eleksmaker A3 machine (smaller footprint) you have, with a Z-axis, but running Marlin on an inexpensive ArduinoMega/RAMPS board stack...

Eleksmaker A3 laser engraver with 60mm Z-axis conversion (0 min 8 sec)


The comma-delimited gcode syntax... along the the number of decimal places, etc... will all be important when you get to the point of running from gcode files. But, right now, just getting a sender program in place, that connects properly through USB, and gives a way to manually jog the axis is what I'd be focused on. I'm still not sure how you are trying to connect and control your board... are you trying to use the Benbox software? Are you open to trying a different gcode sender program... Universal Gcode Sender, Grbl Controller, etc?
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Jun 15, 2019, 10:54 AM
Danish? Don't U eat that??
DKChris's Avatar
If the connections btw. the nano and the different stepper driver pins (which are standard A4988 stepstick/polulu devices, so their pinout should be fairly easy to find) and the input pins can be sketched up, it should be reasonable to figure out how to setup the GRBL pinout; Heck it might actually use the stock pinout, we just don't know at this point.

Stepstick module pinout can be found on this page: https://www.pololu.com/product/1182

I so far haven't been able to find a standard pinout schematic for the Nano for GRBL1.1e, but here's a link to one for the 0.8/0.9 versions: http://forum.eleksmaker.com/topic/28...-in-t2-laser/6, guessing the differences ought to be minimal. also attached the pic.

THEN! I actually found a pinout for the eleksmaker nano while searching for the above link - pic attached.

They don't look all too different to me to be honest. Step and dir pins are identical. Now, what I'd like to know is if the probe pin on the eleksmana connects to D9 on the nano, and especially if the hold pin connects to D8!! I'm pretty sure something needs to be done with this nano pin to make things move.
Jun 15, 2019, 11:35 AM
treefinder
springer's Avatar
David and DK, thanks for the helpful comments. To your questions. First off, I have been using a BenCutLaser program on my laptop to drive the machine. This software was developed as an enhancement to the benbox that came with the original machine from banggood (2 axis laser). I got it and used it some with the original laser setup before getting the idea to enlarge it and add the Z axis, so figured the move up on size and axes would be fairly simple. I am coming to the opinion that there may be laser specific function/setting that prevents things from happening if not set or activated. Since all I really want at the moment (as you said) is to move the head around under control, i don't really need all the extras BCL provides. So, (great minds) i started looking at universal g-code sender just before getting on rcg!

Given that, in you guys minds would that one be the best for use on a win10 machine? And for an obvious noob?

Also, to your questions, I have been doing the start up sequence of USB then power. Checking in windows ports screen, com port 8 shows a connection to the board: USB-serial ch340 (com8). So that part of the system seems to work. On the comma vs period, I saw that earlier, will have to check further just to be sure. When i flash or update from BenCut, the communication window seems to show communication both ways, but when i jog or send a simple g- code circle and square nothing shows, so something seems to stop the send.

I guess my next step will be to get a more generic Grbl sending program. I will check all the links you guys posted, of course. Thanks.
Jun 15, 2019, 03:31 PM
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Quote:
Originally Posted by DKChris
If the connections btw. the nano and the different stepper driver pins (which are standard A4988 stepstick/polulu devices, so their pinout should be fairly easy to find) and the input pins can be sketched up, it should be reasonable to figure out how to setup the GRBL pinout; Heck it might actually use the stock pinout, we just don't know at this point.

Stepstick module pinout can be found on this page: https://www.pololu.com/product/1182

I so far haven't been able to find a standard pinout schematic for the Nano for GRBL1.1e, but here's a link to one for the 0.8/0.9 versions: http://forum.eleksmaker.com/topic/28...-in-t2-laser/6, guessing the differences ought to be minimal. also attached the pic.

THEN! I actually found a pinout for the eleksmaker nano while searching for the above link - pic attached.

They don't look all too different to me to be honest. Step and dir pins are identical. Now, what I'd like to know is if the probe pin on the eleksmana connects to D9 on the nano, and especially if the hold pin connects to D8!! I'm pretty sure something needs to be done with this nano pin to make things move.
I'm pretty sure the GRBL spec is what drives the pinout on the Nano and Uno devices. I can't imagine the 1.1e would break backward-compatibility and/or a persons' ability to update to a more recent version. When I was playing with my Inexpensive Linux Interface and the stepstick devices, it was all pretty standard stuff.

I don't have a clue about the probe and hold pins... so can't help there.

-- David
Jun 15, 2019, 10:21 PM
treefinder
springer's Avatar
Ha! Success! or at least the beginning of success. I downloaded universal g-code sender this afternoon and got it set up. Fortunately already had Java 8. powered up the machine and tried jogging each stepper. Heard and felt some vibration, but didn't see any movement, which was more than I had previously. I tried it a couple of times, saw that the window was showing movement in tiny steps, and if I looked close at the gantry, could see tiny steps of movement. Tried playing with speeds and got real movement. Loaded a test file (circle and square) and it moved all axes to generate the shapes. I need to set up a pen or something to check accuracy, I guess. The thing I need now to do is get directions correct. As the picture shows, with me sitting at the controller, X runs positive to the left, Y positive toward me, and z positive down. I found a great page that explains all the command structure, so know that $3 changes the direction. How do you guys set up your machines? I'm guessing that positive Z should be up, not down, but how about X and Y? Seems like Y should be reversed as well so cut parts will sit correct relative to the drawing files. My next step will be to check if the commanded movement is the actual movement and then adjust the values in $100, $101 and $102, correct?

I also, looking at things moving, decided that I need to remake the Z axis mounting unit to move it all lower, closer to the board. Right now the tip of the mig tip of the needler is 3.5" off the mdf base board at Z axis about 20mm above it's minimum. I think I can move the assembly about 2" down and still have room for waste board of 3 sheets of MPF plus the work sheet. More fun 3D printing!

Getting excited!
Last edited by springer; Jun 15, 2019 at 10:42 PM.
Jun 15, 2019, 11:19 PM
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Quote:
Originally Posted by springer
Ha! Success! or at least the beginning of success. I downloaded universal g-code sender this afternoon and got it set up. Fortunately already had Java 8. powered up the machine and tried jogging each stepper. Heard and felt some vibration, but didn't see any movement, which was more than I had previously. I tried it a couple of times, saw that the window was showing movement in tiny steps, and if I looked close at the gantry, could see tiny steps of movement. Tried playing with speeds and got real movement. Loaded a test file (circle and square) and it moved all axes to generate the shapes. I need to set up a pen or something to check accuracy, I guess. The thing I need now to do is get directions correct. As the picture shows, X runs positive to the left, Y positive toward me, and z positive down. I found a great page that explains all the command structure, so know that $3 changes the direction. How do you guys set up your machines? I'm guessing that positive Z should be up, not down, but how about X and Y? My next step will be to check if the commanded movement is the actual movement and then adjust the values in $100, $101 and $102, correct?

I also looking at things moving, decided that I need to remake the Z axis mounting unit to move it all lower, closer to the board. Right now the tip of the mig tip of the needler is 3.5" off the mdf base board at Z axis about 20mm above minimum. I think I can move the assembly about 2" down and still have room for waste board of 3 sheets of MPF plus the work sheet. More fun 3D printing!

Getting excited!
Super news, Springer! Sounds as if you are on the right track...

I'd leave the Z-axis alone for the moment... having it safely way up in the air and out of the way is a good thing while you do the rest of the setup.

Get each axis moving in the right direction first. Don't have a Grbl machine set up at the moment but $3 is indeed the direction mask. Set the value according to the page you found.. As you are looking at the machine...movement should be X positive to the right, Y positive away from you, and Z positive UP, as you suspected.

Then get the steps/mm set up for each axis... $100, $101, $102 for X, Y, and Z. Get a ruler with metric scale... and lay it on the worksurface, safely out and away from the edges and inline with the axis you're testing. Rubber band or strap a skewer (pointed object) to the tool mount with the pointed end fairly close to the ruler. Align the pointer with 0 on the ruler. Command a small move first... 10mm is probably safe. See if the tool moved 10mm. If it seems close enough to safely move 50mm then command 4 more 10mm moves... for a total of 50mm worth of movement. Note how far on the ruler it actually moved... say, it moves 42mm. So, use the following easy calculation to adjust the steps/mm for that axis.... say, X

(commanded / actual) * (the current value in $100)

So, if the current value of $100 is 250.00... (50 / 42) * 250 gives 297.62. Type "$100=297.62" on the command line and send it... then $$ to verify it's been changed to 297.62. That simply means that 250 steps/mm only moved you 42mm... so you needed more steps/mm to move 50mm. X and Y axis are probably the same as the motors/pulleys/belts are all the same. Z will probably be different as it's leadscrew driven and has different drive ratios... but the calculation still holds true.

Do that for all three axis and now you should be able to see things moving in the right direction and by the right amounts. This will get you close for now... you can fine tune it better by commanding larger moves... i.e. command 500mm movement, see only 498.5 actual... and compute the new value.

Get that done and you are on your way. Good luck. -- David
Last edited by dkj4linux; Jun 16, 2019 at 07:45 AM.
Jun 16, 2019, 08:51 AM
treefinder
springer's Avatar
Sounds like I have my afternoon cut out for me! (No pun intended)

Your guidance on leaving Z high is good, I haven't thought about a skewer pointer! It will stay high until I revise the carriage design and reprint in any case. As with most stuff I do nowadays, I think of new functions and improvements once I get anything built! "The iterative process". I just have a good incentive - 3" thick spoiler board might be excessive. . . Though would allow big chambers for vacuum. Hmmm.

The difference between XY and Z axis movements had me going for a bit. I got the X and Y moving good, but Z motor rotated a bit but that only translated into a mm of carriage movement. Then it dawned on me the reduction from the screw. The motor is different from the X/Y motors, so I expected different function, but it seems to be "happy" with the others. So far so good, though.

It was also interesting that the bewilderment of Grbl has started to fade. I searched for a good while on the web for some chart or list of commands and what they do. Finally yesterday, found one and after reading through it and comparing to the printout of the setup my other program (BenCutLaser) sent to the arduino, began to understand it all. As it turns out, the setup is pretty generic, only the $ command to enable laser operation was specific as far as I can tell. Grbl is v1.1e, so up to date . I suspect that the lack of movement was due to a program specific issue or the too few steps per jog I found in UGS. If I add a laser head to it I will have to look at it again, but for now will stay with what works.

Thanks again for all your help!
Jun 16, 2019, 12:23 PM
Danish? Don't U eat that??
DKChris's Avatar
Actually, you could also choose to change the direction of the stepper(-s?) in hardware and keep the software stock. It's quite simple. Take a look at that pinout schematic for each of the ports i linked to in post #242; To change direction you simply need to swap the 2 pins for one of the 2 stepper motor coils, so either A+ with A- or B+ with B-. But only one; if you swap both you end up with it still turning in the same direction.

Physically, you just take out the stepper plug, make a note of the colors of the leads, figure out which to swap, pry out the 2 connector inserts and reinsert them swapped. As an extra safety you can doublecheck which pins belong to the same coil by measurering the resistance between the different pins. A pair that belong together should have something like 10-50ohm resistance between them, and the coils are electrically isolated from each other.
Last edited by DKChris; Jun 16, 2019 at 01:25 PM.
Jun 18, 2019, 08:45 AM
treefinder
springer's Avatar
Well, Sunday afternoon was an educational time. I got steppers going the right directions, played with step accuracy. Got x and y to about 1 mm in 500. Some of that may be belt tension issue. I am thinking about drawing up a tensioner that I can adjust with a screw driver instead of the pull the belt and screw it down I now have. Z axis was the biggest challenge with the totally different parameters of the jackscrew. Using the formula, I got an 800 multiplier (10X the original 80 steps). When I applied it, got all sorts of noise from the motor. After fiddling with the numbers, I remembered David's comment on too fast causes lost steps and cut the speed from 2000 ( which worked fine for X,Y) to 500. That smoothed out the Z. Now need to make a "tray " of sorts to hold lipo, esc and servo tester so I can try out the needle. Comin' along. . .
Jun 18, 2019, 12:38 PM
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Quote:
Originally Posted by springer
Well, Sunday afternoon was an educational time. I got steppers going the right directions, played with step accuracy. Got x and y to about 1 mm in 500. Some of that may be belt tension issue. I am thinking about drawing up a tensioner that I can adjust with a screw driver instead of the pull the belt and screw it down I now have. Z axis was the biggest challenge with the totally different parameters of the jackscrew. Using the formula, I got an 800 multiplier (10X the original 80 steps). When I applied it, got all sorts of noise from the motor. After fiddling with the numbers, I remembered David's comment on too fast causes lost steps and cut the speed from 2000 ( which worked fine for X,Y) to 500. That smoothed out the Z. Now need to make a "tray " of sorts to hold lipo, esc and servo tester so I can try out the needle. Comin' along. . .
Great news, Springer!

There a few alternative belt clamp/tensioners out on Thingiverse already... you might want to check them out before spending a lot of time doing yet another. Search for "eleksmaker a3 belt" out on TV and that should bring up several...

Also, have you tried getting that last mm calculated out? Multiply 1.002 (that's 500/499) by your current value and use that as your new steps/mm. That would be quicker to do than making new tensioners (although you may still want to do that as well).

Yeah, you gotta slow down the speed for leadscrew-driven axis... I'm still using 5/16" threaded rod on mine. If you try to drive a stepper too fast it'll just make ugly noises without really moving.

I've just about decided to revisit my little Eleksmaker A3 machine... the one with the printed Z-axis and a 3.5 watt laser mounted on it. I could remove the Mega/RAMPS board set running Marlin and switch it over to Grbl... maybe to sort of get "in step" with you. I have a couple of 3-axis Nano+A4988 controllers that came on the cheapy mini-mills sold by HobbyKing... it's not exactly like the Eleksmaker board you're using but it's close enough and currently flashed with Grbl 0.9j. But I also have another MKS Gen L v1.0 controller that could be used to keep it Marlin based. Hmm... hmm...

-- David
Last edited by dkj4linux; Jun 18, 2019 at 01:48 PM.
Jun 18, 2019, 02:56 PM
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Can't nap ALL the time...


A bit of digression, some exploration, a dose of boredom, 3dprinter sitting idle, parts on hand, a whim of fancy, and a bit of folly... it's PLAYTIME!

Poor FoamRipper. Built originally with Marlin/Mega/RAMPS, I recently took a nostalgic trip back in time to convert it over to LinuxCNC, the control software I started with, way back in my initial forays into CNC. I had used it, along with SketchUp and the Phlatboyz CAM extensions, to create gcode for all the little bluecore fan-fold foam aircraft my late flying/fishing buddy and I flew in my pasture... as well as all the parts for a second CNC machine for him. I really do like LinuxCNC and thoroughly enjoyed developing the inexpensive LinuxCNC interface documented in this thread... but, by today's standards (Marlin/Grbl), it is a bit big and clunky. And since there seems little interest, beyond my own -- and my curiosity is now satisfied -- it's time to move on to something new.

I've built more than a dozen CNC machines over the past several years and virtually all of them started with Marlin/Mega/RAMPS. Since I had a number of the little board sets that I knew worked, I kept using them. One of the machines still in use, an MPCNC laser engraver, sports a miniRambo board now... having been used to help debug a laser raster-engraving issue in newer versions of Marlin, over on the V1Engineering forum.

Somewhere along the way, however, I picked up a couple of MKS Gen L v1.0 controllers. I don't remember exactly why... other than they were supposedly 100% compatible with the Mega/RAMPS combo I'd been using and was so familiar with.

The digression and exploration... I reverted the FoamRipper to the Marlin/Mega/RAMPS scheme from before. However, I used the MKS Gen L v1.0 board this time. I flashed it with the Marlin/RAMPS firmware from the V1Engineering site and applied the RAMPS "pin44 remap" mod (isolated white wire) and set it up for the full-graphics LCD display.

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The isolated white and gray wires are the RAMPS "remapped Fan1 to pin 44" mod for TTL laser modulation, using M107 and M106 Sxxx gcodes for control...

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Boredom and fancy... I had thought I might play with putting a laser on the FoamRipper. Pretty useless, really -- diode lasers won't cut foam-board -- but I thought it could be fun to play with as an engraver. So, my compact carriage and Z-lift got a new appendage and became a bit the monstrosity... sporting one of the never-used Eleksmaker 2.5 watt laser modules I had on hand. Pen/marker, needle-cutter, and now laser... all mounted on the same carriage together.

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And, in action...

Garfield on laser-enabled FoamRipper (0 min 12 sec)


So, it works... but is of dubious value. But it keeps me off the streets and gives me something to do between naps

-- David
Jun 18, 2019, 05:53 PM
treefinder
springer's Avatar
There a few alternative belt clamp/tensioners out on thingiverse already... You might want to check them out before spending a lot of time doing yet another. Search for "eleksmaker a3 belt" out on tv and that should bring up several...

i will take a look. Found one for my anet a8 x axis some time ago, didnt think about the eleksmaker search.


also, have you tried getting that last mm calculated out? Multiply 1.002 (that's 500/499) by your current value and use that as your new steps/mm. That would be quicker to do than making new tensioners (although you may still want to do that as well).

i did several iterations, and bounced around the 500, +/- a mm or two, which led me to think belt tension. I found one y belt was looser than the other. I would like a tensioner i can dial in vs the stock way.

yeah, you gotta slow down the speed for leadscrew-driven axis... I'm still using 5/16" threaded rod on mine. If you try to drive a stepper too fast it'll just make ugly noises without really moving.

Yup exactly what happened. Lots of noise, no movement. After I changed the stepper parameter, I also made the z max speed parameter the same 500. Then I increased the stepper number and tried. The global parameter over road the individual one. Good.

I've just about decided to revisit my little eleksmaker a3 machine... The one with the printed z-axis and a 3.5 watt laser mounted on it. I could remove the mega/ramps board set running marlin and switch it over to grbl... Maybe to sort of get "in step" with you. I have a couple of 3-axis nano+a4988 controllers that came on the cheapy mini-mills sold by hobbyking... It's not exactly like the eleksmaker board you're using but it's close enough and currently flashed with grbl 0.9j. But i also have another mks gen l v1.0 controller that could be used to keep it marlin based. Hmm... Hmm...

More tinkering, can't be bad!
Last edited by springer; Jun 18, 2019 at 06:03 PM.
Jun 23, 2019, 01:17 PM
treefinder
springer's Avatar
Had almost a full day of rain this week and worked inside on my cutter. It took almost 3" of foam (MPF seconds) to get the workpiece up to the cutter. (Next project will be a 2" dropped Z axis frame!) Played with zeroing, and realized my normal format for layout (landscape) won't work if I have XY zeros at lower left corner. Easy enough to rotate in sketchup and export via wafer plugin. Powered her up and started cutting. All went well except for the lack of flatness in the foam combined with not enough retraction in Z made lots of partial tracks across the sheet. I was going up 10mm, increased to 20 and that problem solved. Next learning was my lack of wire management allowed one Y carriage to try running over the wires. Stalled and lost many steps. Made a really short wing! Another project : manage wires! I found a wire chain on thingiverse that I am revising and printing links to fit in a 3/4 " AL U channel that I will attach to the Y size pieces. Hopefully that will take care of the "dragging across the work surface" issue. I also broke my first needle after the equivalent of 3-4 sheets cut. It broke right at the crank bearing. I would have thought that the bearing would prevent breakage there. I may have kinked the wire in bending it, though. I found some round nose pliers and used them to make the replacement perhaps that will survive longer (smooth round eye).

I am running at 1500mm/min for cutting and the original needle wasn't well pointed (just as cut, not ground to a point) so the changes in sound in the vid may be that. My new needle extends about 15mm from the guide fill down, and I set zero at guide about 5mm off the foam surface. Does that sound right?

I will say that I am really impressed at the smooth square foam edges it produces!

(1 min 12 sec)
Last edited by springer; Jun 23, 2019 at 01:24 PM.
Jun 23, 2019, 06:05 PM
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Quote:
Originally Posted by springer
Had almost a full day of rain this week and worked inside on my cutter. It took almost 3" of foam (MPF seconds) to get the workpiece up to the cutter. (Next project will be a 2" dropped Z axis frame!) Played with zeroing, and realized my normal format for layout (landscape) won't work if I have XY zeros at lower left corner. Easy enough to rotate in sketchup and export via wafer plugin. Powered her up and started cutting. All went well except for the lack of flatness in the foam combined with not enough retraction in Z made lots of partial tracks across the sheet. I was going up 10mm, increased to 20 and that problem solved. Next learning was my lack of wire management allowed one Y carriage to try running over the wires. Stalled and lost many steps. Made a really short wing! Another project : manage wires! I found a wire chain on thingiverse that I am revising and printing links to fit in a 3/4 " AL U channel that I will attach to the Y size pieces. Hopefully that will take care of the "dragging across the work surface" issue. I also broke my first needle after the equivalent of 3-4 sheets cut. It broke right at the crank bearing. I would have thought that the bearing would prevent breakage there. I may have kinked the wire in bending it, though. I found some round nose pliers and used them to make the replacement perhaps that will survive longer (smooth round eye).

I am running at 1500mm/min for cutting and the original needle wasn't well pointed (just as cut, not ground to a point) so the changes in sound in the vid may be that. My new needle extends about 15mm from the guide fill down, and I set zero at guide about 5mm off the foam surface. Does that sound right?

I will say that I am really impressed at the smooth square foam edges it produces!

Looking good, Springer! It looks as though things are really starting to take shape.

The most obvious thing to me is that 1500 mm/min is quite fast to be cutting... that's more than 2x the feedrate I use for DTFB. Then again, I've not cut any MPF so that's not necessarily a bad thing.

More important, do you know the RPM's you are using on the cutter? As the cutter is inherently a pretty sloppy mechanism, higher RPM's on the cutter may allow you to cut faster but it also increases the rate of wear and tear on the cutter. That may, or may not, be why your needle decided to break prematurely but it's something to consider. My thinking is that the lowest cutter speed that allows an acceptably fast feed rate and decent cuts should yield stress-free operation and longest cutter life. Most of my cutters seem to work pretty well at 6000-8000 rpm... however the slip-on flywheel seems to allow much smoother operation at significantly higher rpms. Also, working with round nose pliers is a good move to help prevent stress risers in the needle wire.

All my Z-axis measurements are referenced to the material surface... not the needle's projection from the guide. I start the cutter running and then lower the Z-axis until I HEAR the needle contact the material surface... and then set Z=0. From there the clearance above the material for travel moves is a POSITIVE Z movement... and the depth of cut is a NEGATIVE Z movement equal to the material thickness plus a couple of millimeters. A vacuum pad would, of course, help with keeping the material flat but it isn't a necessity... I cut for years without one. One trick I used was to place the material on the spoilboard "crown down", like a dinner plate, and then hold down the edges with pins or weights. Another trick is to spread small bean bags around on the work surface and then move them around during the cut to keep the material as flat as possible.

I've shown this video before but note the Z-axis movement to touch to material (~ 2 min mark)... it's very obvious and allows very accurate setting of Z=0...

FoamRipper job setup (4 min 2 sec)


Again... good work!

-- David
Jun 23, 2019, 06:42 PM
treefinder
springer's Avatar
Should have read back through the thread. I was thinking 1500mm/min was what you were using. I can for sure slow down the traverse speed. Depending on direction, it sounded like it was working pretty hard pushing through. I will try a thousand then less and see how she idoes. I'm using a 2s lipo, but a 1500kv emax 2812 motor, so definitely getting different speeds than a 3S 2822. About 3/4 throttle it seems to smooth out in free run (not in the foam) mode, so I have been cutting at that speed. I have a tach sensor, but last time I tried to use it on an actual prop, it picked up the florescent lights instead of the prop. Not sure I can give you good rpm nunbers. I suppose the proof is in the running, have to just try more variations.

On the flattening, I have some half inch 4'x8' foamular board that I think I will use, as it is really flat, maybe think about some grooves for vac table function. I am following your guidance with crown down work piece, but the MPF seconds sheets I am using have lots of waves and MPF is less rigid than dtf with paper on (which I assume your were cutting?) Increasing retract distance seems to work ok for now. I need to scrounge some pipe or bar stock for the sides, though in absence of suction.

I will have to ponder the z axis registration. How far out of the nozzle does your needle extend full down? If you register zero at work piece surface and needle full down, how far into the foam do you typically run? I am thinking that the deeper it goes the more side loading it gets? Right now mine extends ~15mm from tip and I set the guide about 5mm above the work surface. 10mm into foam or two thicknesses. Sound right?

It occurs to me that your zeroing sets you up nicely for partial or score cuts!

Gotta say, though that this machine is pretty cool concept. Plaudits to you and the others who came up with it!


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