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ZincBoy
May 6, 2006

Think again Jimmy!

NewFatMike posted:

Mach 3 just kinda fuckin sucks, huh?

Seems like there are some endemic signal issues regardless of configuration. I almost got 10% into a job before the software poo poo the bed and continues to poo poo it.

I've had a lot less trouble with GRBL, somehow also ShopBot control, and I'd consider trading a finger or toe even for PathPilot.

What are y'all using to control your home machines?

LinuxCNC with Mesa electronics FPGA hardware step generation. I was running the PCIe FPGA cards on my lathe and Novakon mill. Now I am running the ethernet FPGA card on the VK45 machining center.

I also ran it with the software step generation 10 years ago but I haven't tried it recently. It is pretty bullet proof for hobby level machines. I hit a few corner cases that were not well tested when running it on a machining center with probing.

PathPilot is a GUI for LinuxCNC running on the Mesa cards.

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NewFatMike
Jun 11, 2015



Oh hell yeah. I knew PathPilot was LinuxCNC based. Is there a good guide or kit link?

Methylethylaldehyde
Oct 23, 2004

BAKA BAKA


NewFatMike posted:

Oh hell yeah. I knew PathPilot was LinuxCNC based. Is there a good guide or kit link?

There is a way to jailbreak a Tormach pathpilot install to run on basically anything via judicious editing of the linux CNC config underlying the install. Not aware of any good guides on how to do it, but it's entirely possible to do.

NewFatMike
Jun 11, 2015



Oh lol, I meant about putting together a mesa + LinuxCNC build. I'm sure I can find something serviceable with those keywords, but it never hurts to ask.

ZincBoy
May 6, 2006

Think again Jimmy!

NewFatMike posted:

Oh lol, I meant about putting together a mesa + LinuxCNC build. I'm sure I can find something serviceable with those keywords, but it never hurts to ask.

The LinuxCNC forums are quite good for many of those details.
Here is a starting point:
https://forum.linuxcnc.org/27-driver-boards/37141-mesa-card-basics

There are many options though depending on what you are using and trying to control.

NewFatMike
Jun 11, 2015



Bless you! Thanks a million, I'm very excited about this.

ZincBoy
May 6, 2006

Think again Jimmy!

Made a bad noise on my mill.

https://www.youtube.com/watch?v=wUzFzcxWWHA

Ran a 5/8" tap at 5x the correct feed rate, bottomed out the T&C tool holder and snapped the tap. Luckily the Z axis drive faulted and shut everything down before more than the tap was damaged. Turns out I found a bug in my spindle gear change code and linuxcnc thought the machine was still in high gear. Should have done an air cut to verify that tapping was working correctly but that is what I get for just sending it.

Managed to get the tap back out but it was a pain as it had been pressed down into the bore. The thread pretty much had to be re cut backwards to get the tap out which is a pain when the drive square is sheared off.

Rad-daddio
Apr 25, 2017

100% RAD


Ouch, but like you said it could've been worse.

CNC mills just destroy taps when they break. I always default to pecking the remnants out with an appropriate-sized endmill and even then it still looks kind of rough.

Ambrose Burnside
Aug 29, 2007

pensive


i havent done production set-up in a good while but watching a mill crash is still mildly traumatic. all quietly uttering oh noooooo at my monitor, reflexively certain i'll be staying late tonight at a job i haven't worked in years

honda whisperer
Mar 29, 2009



Ambrose Burnside posted:

i havent done production set-up in a good while but watching a mill crash is still mildly traumatic. all quietly uttering oh noooooo at my monitor, reflexively certain i'll be staying late tonight at a job i haven't worked in years

Where I work the best part is hearing the crash and right after everyone makes sure it wasn't them popping up like prairie dogs to see who it was.

Usually the missing head just crashed.

Unless it's like the guy who removed the part and jaws from the chuck and changed the angle of the turret in one glorious full send adjustment. Then people wander out of the front office.

biracial bear for uncut
Jun 9, 2009

ask me about being the most obnoxious person of all time

Ambrose Burnside posted:

i havent done production set-up in a good while but watching a mill crash is still mildly traumatic. all quietly uttering oh noooooo at my monitor, reflexively certain i'll be staying late tonight at a job i haven't worked in years

For me it's the reflexive flinching expecting some kind of cutting or blunt force trauma.

I've been super lucky dodging flying stock and tooling because some rear end in a top hat bypassed the safeties on a machine and it blindly attempted a move that would have been prevented if soft stops were properly set up in the settings (or if proper tool touchoffs were done, etc.).

I wish OSHA did proper surprise inspections instead of giving a company a warning letter letting them know when they're coming by.

Ambrose Burnside
Aug 29, 2007

pensive


biracial bear for uncut posted:

For me it's the reflexive flinching expecting some kind of cutting or blunt force trauma.

I've been super lucky dodging flying stock and tooling because some rear end in a top hat bypassed the safeties on a machine and it blindly attempted a move that would have been prevented if soft stops were properly set up in the settings (or if proper tool touchoffs were done, etc.).

I wish OSHA did proper surprise inspections instead of giving a company a warning letter letting them know when they're coming by.

my "there but for the grace of god go i" moment was when I got hit in the face by a runaway bench grinder wheel thanks to someone putting a wheel on without securing the nut, compounded by me not double-checking the setup before i went to work, or stopping to replace the guard that had been taken off. whenever the torque reversed when I started grinding the nut would back off a couple of threads, bit by bit, until the wheel dropped off, bounced once on the table- i remember thinking it was a cute little hop, instead of hitting the deck like i should have- and then it launched sideways across the as the spin finally imparted some good momentum from contacting the table

i am incredibly loving lucky that it basically did a nosegrind along my jaw and up across my face without impacting bone, i got a nasty strip of friction burn across the left entire side of my face but if it had been an inch lower it would have destroyed my nose/jaw/teeth or worse b/c that sucker was heavy and moving fast. i am a deeply paranoid measure-thrice-or-even-four-times guy now, and that's fine b/c you don't often get a mulligan on that close a call

Ambrose Burnside fucked around with this message at 03:16 on May 7, 2021

biracial bear for uncut
Jun 9, 2009

ask me about being the most obnoxious person of all time

Oh, I've taken some hard hits, too. Had a narrow strip of UHMW-HDPE slide off the side of a conveyer as it was going along said conveyor, miss me the first time as it was going, the far end catch on a divot in the concrete floor, arch up and rebound straight into my face below my nose and crush my upper lip into my teeth (someone else that witnessed it said it looked like a 20 foot long snake strike).

Sent me staggering and fighting to remain conscious for several minutes, and gave me a hilarious bruise in the shape of the end profile of the part.

Machine shops have all sorts of hazards people don't think about until poo poo hits the fan.

ZincBoy
May 6, 2006

Think again Jimmy!

I have had a few crashes with this machine as I find bugs in the control configuration or my programming. This is the stressful part of retrofitting a machining center. The power of the machine requires much more respect than a hobby class machine. The x and y servos on this machine are 1.5kW, more than the spindle motor on any of my old machines.

First crash was due to the G43 tool offset being cleared after a fault causing the z axis to rapid into the part. I now set up my tool offsets (negative values) so that clearing them causes the axis to move away from the work rather than towards it. This was a fun one because I was milling a hole in a 2" diameter ball bearing and the z axis hit hard enough to press the ball into the vice and dent the vice. The vice had a raised ring around the dent that had to be stoned out.

Next one was crashing the renishaw probe stylus into the work. Luckily it was a ceramic shaft stylus so it just exploded all over rather than damaging the probe. This one was how I discovered that there was a bug in LinuxCNC where it would not stop when the probe input trips on non-probe moves. It was supposed to stop, but didn't and I found out the hard way. I submitted a patch to fix this and it should be in the next version.

Then there is the tap:

It is hard to see in the picture but there is a nice spiral fracture running from the drive end all the way to the flutes.

All these crashes are why I have not rebuilt the spindle yet. I have the bearing for it but I want to get it running stable to minimize the risk I will immediately crash brand new bearings

Anyway, this is what I was making:




Both parts were made on the mill and really should have been done on a lathe but where would the fun be in that? It is a spherical bearing mount for a jib crane I am working on.

It was the first time I had run a thread mill and it turned out quite well. A 2.95" 18TPI

Rad-daddio
Apr 25, 2017

100% RAD


ZincBoy posted:

I have had a few crashes with this machine as I find bugs in the control configuration or my programming. This is the stressful part of retrofitting a machining center. The power of the machine requires much more respect than a hobby class machine. The x and y servos on this machine are 1.5kW, more than the spindle motor on any of my old machines.

First crash was due to the G43 tool offset being cleared after a fault causing the z axis to rapid into the part. I now set up my tool offsets (negative values) so that clearing them causes the axis to move away from the work rather than towards it. This was a fun one because I was milling a hole in a 2" diameter ball bearing and the z axis hit hard enough to press the ball into the vice and dent the vice. The vice had a raised ring around the dent that had to be stoned out.

Next one was crashing the renishaw probe stylus into the work. Luckily it was a ceramic shaft stylus so it just exploded all over rather than damaging the probe. This one was how I discovered that there was a bug in LinuxCNC where it would not stop when the probe input trips on non-probe moves. It was supposed to stop, but didn't and I found out the hard way. I submitted a patch to fix this and it should be in the next version.

Then there is the tap:

It is hard to see in the picture but there is a nice spiral fracture running from the drive end all the way to the flutes.

All these crashes are why I have not rebuilt the spindle yet. I have the bearing for it but I want to get it running stable to minimize the risk I will immediately crash brand new bearings

Anyway, this is what I was making:




Both parts were made on the mill and really should have been done on a lathe but where would the fun be in that? It is a spherical bearing mount for a jib crane I am working on.

It was the first time I had run a thread mill and it turned out quite well. A 2.95" 18TPI

Nice part.

I think 70% of the things that I would normally do on a lathe, I end up doing on the cnc mill bc there's a secondary feature that would need to be milled anyways.

Rad-daddio
Apr 25, 2017

100% RAD


Here's a portable CNC lathe I've been working on. I need a smaller machine for short run jobs, and I also wanted to take a stab at converting a lathe to cnc so I could apply those skills to a larger machine later on.

This guy is a Sieg benchtop lathe that was on CL for a hundred bucks. The guy was selling it because he damaged some of the plastic threading gears and had no more use for it.

I stripped everything off, and made the baseplate from an anodized alu part that one of my customers didn't need anymore. I drilled some mounting holes, and as luck would have it it fits perfect on top of this toolbox.

I've been printing out test pieces for the various conversion bits before I make them out of aluminum, but I might keep the encoder holder as is if it holds up. The monitor mount is a repurposed mini dish mount, and the keyboard/mouse platform is made from some sheet metal parts that I biffed years ago. After a lot of tinkering, I finally got the z axis ballscrew and motor mount how I wanted them. The electronics will be mounted in a case on the backside of the toolbox. I'm still up in the air on the x axis, because I want to do gang tooling but my instinct is telling me to keep it simple and just manually change tools for this project. idk...

The overall project goal is to have an enclosed lathe with mist coolant, and have it be portable to the point where I can still plug it into a 120 outlet like the new Tormach mini cnc lathe.







NewFatMike
Jun 11, 2015



Oh that is way too cool - please keep posting updates! Keeping it mobile on the tool chest is real interesting. Any plans for reducing resonance?

ZincBoy
May 6, 2006

Think again Jimmy!

Rad-daddio posted:

I've been printing out test pieces for the various conversion bits before I make them out of aluminum, but I might keep the encoder holder as is if it holds up. The monitor mount is a repurposed mini dish mount, and the keyboard/mouse platform is made from some sheet metal parts that I biffed years ago. After a lot of tinkering, I finally got the z axis ballscrew and motor mount how I wanted them. The electronics will be mounted in a case on the backside of the toolbox. I'm still up in the air on the x axis, because I want to do gang tooling but my instinct is telling me to keep it simple and just manually change tools for this project. idk...

The overall project goal is to have an enclosed lathe with mist coolant, and have it be portable to the point where I can still plug it into a 120 outlet like the new Tormach mini cnc lathe.

Very nice so far. I am still running the 3d printed mount for the spindle encoder on my lathe and it has been running for 5 years now. There is no real stress on that part so plastic should be fine.

On the tool holder front, I also had plans/dreams of gang tooling or a turret but have never taken the plunge. Running a wedge style quick change tool post works fine for the very limited runs of parts I make. Changing the tools is repeatable enough that you can swap them without touching off.

On the enclosure front, one thing I learned is that you have to be really careful to insure there are overlaps on any openings or joints. Otherwise it will leak. Mist coolant might be better for this, but running flood coolant is like having a pressure washer hose flopping around inside the enclosure.

My lathe today:


It is a 10x22 lathe stripped down and put in an enclosure. Most of the time I use it as a semi-auto lathe with conversational cycles.

Rad-daddio
Apr 25, 2017

100% RAD


Nice setup!

What UI are you using for linuxcnc? I've got it installed on the computer, but I still have to configure the electronics so I was holding off on that headache for now.

Rad-daddio
Apr 25, 2017

100% RAD


NewFatMike posted:

Oh that is way too cool - please keep posting updates! Keeping it mobile on the tool chest is real interesting. Any plans for reducing resonance?

I was thinking of going with a beefier baseplate if vibration is an issue. Believe it or not, I have a chunk of ground 304 that I can fin into that same spot on the toolbox. It was a holdover from a long finished job, and the chuck is too big for me to use for anything else.

ZincBoy
May 6, 2006

Think again Jimmy!

Rad-daddio posted:

Nice setup!

What UI are you using for linuxcnc? I've got it installed on the computer, but I still have to configure the electronics so I was holding off on that headache for now.

I am using Gmoccapy as the UI. The monitor is an old monoprice resistive touch screen. The resistive screen works quite well even if your hands are covered in coolant.

Rad-daddio
Apr 25, 2017

100% RAD


Does anyone know the specific tradeoffs/benefits for running a timing belt and a pulley on your stepper motors? I'm going that route for my lathe x axis to make to make toe motor position more compact, but from what I've read online it allows for greater accuracy if you run a smaller pulley on the motor.

Also, I guess setting belt tension requires a bit of finesse.

ZincBoy
May 6, 2006

Think again Jimmy!

Rad-daddio posted:

Does anyone know the specific tradeoffs/benefits for running a timing belt and a pulley on your stepper motors? I'm going that route for my lathe x axis to make to make toe motor position more compact, but from what I've read online it allows for greater accuracy if you run a smaller pulley on the motor.

Also, I guess setting belt tension requires a bit of finesse.

The biggest thing to watch for is speed. A belt reduction will reduce your max axis speed and with a stepper it may be too low to be acceptable. It does increase torque but that is not much of a concern with appropriately sized steppers.

The other issue is the increase in backlash and compliance of the axis. The belt is not infinitely stiff and will increase deflection of your axis. With good design this is not an issue but it is something to look at.

You will need to provision some tensioning method as well. I use an app on my phone to check belt tension. You hit the belt and the app measures the resulting tone and will let you know if the frequency is in the right range.

On my lathe I use a 4:1 belt reduction but I am running DC servos with a 3000rpm rated speed. With the 4:1 reduction and 5mm pitch ball screw, I have a max rapid speed of 140ipm. With the plain ways on the lathe this is about as fast as you would want to go. With a stepper, the 750rpm ball screw speed would be achievable with direct drive and maybe a 2:1 reduction.

Since I have a 1250lpr encoder, the theoretical resolution is 101600 steps/inch or 1e-5 inches. In reality, the backlash in the belt, ball screw, and ways plus the belt stretch and machine deflection limit the effective resolution to around 0.0001".

If I was using steppers, I would aim to direct drive the ball screw. The closed loop steppers would also be a good idea to increase the real resolution of the stepper.

Only registered members can see post attachments!

biracial bear for uncut
Jun 9, 2009

ask me about being the most obnoxious person of all time

Rad-daddio posted:

Does anyone know the specific tradeoffs/benefits for running a timing belt and a pulley on your stepper motors? I'm going that route for my lathe x axis to make to make toe motor position more compact, but from what I've read online it allows for greater accuracy if you run a smaller pulley on the motor.

Also, I guess setting belt tension requires a bit of finesse.

What about linear actuators? Or a rack-and-pinion setup?

Something like this for the actuator? https://www.amazon.com/FUYU-Linear-Actuator-Motorized-Stepper/dp/B0784FYLWV

Maybe something like this for the rack-and-pinion setup (you'll have to make your own mount for the stepper/etc. to connect everything up to your rail on the lathe)? https://www.rovercnc.com/collections/rack-and-pinion/products/straight-rack-and-pinion-kit-modula-1-0-17x17x1500mm

biracial bear for uncut fucked around with this message at 15:47 on May 14, 2021

ante
Apr 9, 2005

SUNSHINE AND RAINBOWS

Is running a belt with steppers a thing? Why? It seems the only benefit of steppers over DC or AC (or even brushless) would be fine speed or position control, which is totally blown up by the slippage inherent in a flat belt

Edit: oh, I thought you were talking about spindles, nm

biracial bear for uncut
Jun 9, 2009

ask me about being the most obnoxious person of all time

ante posted:

Is running a belt with steppers a thing? Why? It seems the only benefit of steppers over DC or AC (or even brushless) would be fine speed or position control, which is totally blown up by the slippage inherent in a flat belt

Edit: oh, I thought you were talking about spindles, nm

I'm assuming it's a beefier version of what hobbyists do with motion control on 3d printers, but still think a belt-driven system is a bad idea on anything where you need real torque to drive a tool on a machine.

Rad-daddio
Apr 25, 2017

100% RAD


ZincBoy posted:

The biggest thing to watch for is speed. A belt reduction will reduce your max axis speed and with a stepper it may be too low to be acceptable. It does increase torque but that is not much of a concern with appropriately sized steppers.

The other issue is the increase in backlash and compliance of the axis. The belt is not infinitely stiff and will increase deflection of your axis. With good design this is not an issue but it is something to look at.

You will need to provision some tensioning method as well. I use an app on my phone to check belt tension. You hit the belt and the app measures the resulting tone and will let you know if the frequency is in the right range.

On my lathe I use a 4:1 belt reduction but I am running DC servos with a 3000rpm rated speed. With the 4:1 reduction and 5mm pitch ball screw, I have a max rapid speed of 140ipm. With the plain ways on the lathe this is about as fast as you would want to go. With a stepper, the 750rpm ball screw speed would be achievable with direct drive and maybe a 2:1 reduction.

Since I have a 1250lpr encoder, the theoretical resolution is 101600 steps/inch or 1e-5 inches. In reality, the backlash in the belt, ball screw, and ways plus the belt stretch and machine deflection limit the effective resolution to around 0.0001".

If I was using steppers, I would aim to direct drive the ball screw. The closed loop steppers would also be a good idea to increase the real resolution of the stepper.



Thanks for the feedback!

I bought a 3:1 pulley and timing belt, but I might not use it and opt for direct drive. I'm using closed loop steppers, and they're sized pretty large for the axis. I may just put it on the back of the axis so it balances out the weight of the apron.

ZincBoy
May 6, 2006

Think again Jimmy!

Rad-daddio posted:

Thanks for the feedback!

I bought a 3:1 pulley and timing belt, but I might not use it and opt for direct drive. I'm using closed loop steppers, and they're sized pretty large for the axis. I may just put it on the back of the axis so it balances out the weight of the apron.

Did you get a GT2 or GT3 type belt? Those are the only ones that I would use for a motion system due to the nearly zero backlash. They also have consistent motion through the tooth engagement unlike the trapezoidal style belts.

Rad-daddio
Apr 25, 2017

100% RAD


It's GT2.

Dominoes
Sep 20, 2007



Hey dudes. Can I use a 3018 to cut 0.5mm-thick aluminum sheets? Any special considerations or bits? Most of the info I find is either about engraving, or cutting 3d shapes. Is there a way to do this in SolidWorks? It seems to be more for 3d shapes as well. I have a Python script that helps me make 2d G-code, but this has the same profile as an existing 3d model I'm using, and it has some curves that I don't know if I could replicate using the script.

NewFatMike
Jun 11, 2015



Go to the ? Icon in the upper right hand corner of SOLIDWORKS, hit "SOLIDWORKS CAM" and there should be an option for "Tutorial" in there, that'll get you started.

I haven't tried any metal in my 3018, but if you find a GRBL post processor, let me know, because that'll save me a lot of guesswork in making one

ZincBoy
May 6, 2006

Think again Jimmy!

Dominoes posted:

Hey dudes. Can I use a 3018 to cut 0.5mm-thick aluminum sheets? Any special considerations or bits? Most of the info I find is either about engraving, or cutting 3d shapes. Is there a way to do this in SolidWorks? It seems to be more for 3d shapes as well. I have a Python script that helps me make 2d G-code, but this has the same profile as an existing 3d model I'm using, and it has some curves that I don't know if I could replicate using the script.

Looks like it should be possible. From what I could find, the 3018 has a 10krpm 60W spindle motor. Using that, HSMAdvisor says that you could run a two flute 1/8" end mill slotting at about 30ipm in 0.5mm aluminum and not exceed your spindle power. You will need to dial that feed rate down (likely to 5 to 10ipm) as the 3018 is not very stiff.

For what you are doing, look for a 1/8" two flute high speed steel uncoated endmill. Idealy specified for aluminum use. Carbide would be a second choice as it won't be as sharp as HSS unless you get into the high end.

You will need to run lubricant or chip welding will clog your endmill in short order. When I used mill aluminum on my cnc router, I would give it a few squirts of WD40 as it was cutting and that seemed to do the trick.

I can't really help with the CAM side. I use BobCad for my CAM at the moment but that is not a low cost/free option. The other system I used to use is Vectric Vcarve and that was a powerful 2.5D system but again not free. I know there are dxf to gcode programs out there but I haven't looked in a long time.

insta
Jan 28, 2009


ZincBoy posted:

Looks like it should be possible. From what I could find, the 3018 has a 10krpm 60W spindle motor. Using that, HSMAdvisor says that you could run a two flute 1/8" end mill slotting at about 30ipm in 0.5mm aluminum and not exceed your spindle power. You will need to dial that feed rate down (likely to 5 to 10ipm) as the 3018 is not very stiff.

For what you are doing, look for a 1/8" two flute high speed steel uncoated endmill. Idealy specified for aluminum use. Carbide would be a second choice as it won't be as sharp as HSS unless you get into the high end.

You will need to run lubricant or chip welding will clog your endmill in short order. When I used mill aluminum on my cnc router, I would give it a few squirts of WD40 as it was cutting and that seemed to do the trick.

I can't really help with the CAM side. I use BobCad for my CAM at the moment but that is not a low cost/free option. The other system I used to use is Vectric Vcarve and that was a powerful 2.5D system but again not free. I know there are dxf to gcode programs out there but I haven't looked in a long time.

The 3018 uses the same brushed DC motors that most cordless drills do (sans gearbox). It is not that powerful, and 10k rpm is extremely generous. I do have the printable files I designed to adapt a 500W spindle to it:



This also let me use the plethora of leadscrews available cheaply on Amazon so I could change to different pitch.

Dominoes
Sep 20, 2007



Awesome dudes! Going to start with Solidworks, and order some apt bits and settings. Ordered some WD-40.

Dominoes
Sep 20, 2007



I might try your mod later, btw!

Dominoes
Sep 20, 2007



What do you mean by a GRBL post processor ? Is that something that converts whatever SolidWorks outputs into something used by Candle / 3018?

I'm considering using my python script, but it's only set up for lines and circles, while this has some fillets. And it has to match closely; this is for a heat plate on the bottom of 3d-printed plastic that prevent warping when exposed to steam. Needs to match the profile.

Ordered this. It's 3/16", so it may not fit, but wasn't able to find 1/8" shank 2-flute HSS. Will flex to carbide if it doesn't fit. The bits I have now are straight 2-flute tungston steel I use for cutting shapes in ABS.

Dominoes fucked around with this message at 18:11 on Jun 5, 2021

babyeatingpsychopath
Oct 28, 2000
Forum Veteran

Dominoes posted:

What do you mean by a GRBL post processor ? Is that something that converts whatever SolidWorks outputs into something used by Candle / 3018?

I'm considering using my python script, but it's only set up for lines and circles, while this has some fillets. And it has to match closely; this is for a heat plate on the bottom of 3d-printed plastic that prevent warping when exposed to steam. Needs to match the profile.

Yes.

Solidworks and other full-featured CNC things produce CAM output that is machine-agnostic. Not every CNC speaks the same flavor of GCODE. G92 on a 3d printer running Marlin does not do the same thing as G92 on a GRBL-based machine. The post-processor is more-or-less a macro substitutor that takes the agnostic CAM output and produces machine-specific GCODE.

Example:
At the beginning, your CAM has something that looks like
{home if not homed}
{move to safe position}

A Marlin Post-processor would take that and output
G28
G0 X0Y0Z0F1000

A GRBL Post-processor takes that exact same thing and outputs
$H
G28

Note that G28 is in both outputs, but means SIGNIFICANTLY different things. If you run GRBL code on your Marlin, it's likely that most of the motion stuff will be OK, but much of the other stuff won't, which means limit switch trips (if installed) or carriage crashes (if not). And vice versa.

edit to add: once you're using Solidworks CAD with CAM, never use python to generate gcode for toolpaths again.

Dominoes
Sep 20, 2007



Thanks! Looking fwd to diving into this tutorial. I'd assumed the CAD software was more for 3D. That's why I was so confused when posting about the scripts earlier! (The scripts work well for things like making the mentioned holes, slots, and rectangles in the top of a plastic enclosure. I ended up using a drill press with a custom jig for drilling holes on the too-tall-for-CNC side, in conjunction with 3d-printed plastic adapters for things like the USB-C port.)

Btw - I experimented with both Fusion and FreeCAD in the past, and never felt like I had a clue. I dove into the SW tutorials and felt competent-for-my purposes in a few days.

insta
Jan 28, 2009


Dominoes posted:

What do you mean by a GRBL post processor ? Is that something that converts whatever SolidWorks outputs into something used by Candle / 3018?

I'm considering using my python script, but it's only set up for lines and circles, while this has some fillets. And it has to match closely; this is for a heat plate on the bottom of 3d-printed plastic that prevent warping when exposed to steam. Needs to match the profile.

Ordered this. It's 3/16", so it may not fit, but wasn't able to find 1/8" shank 2-flute HSS. Will flex to carbide if it doesn't fit. The bits I have now are straight 2-flute tungston steel I use for cutting shapes in ABS.

Do you want something printed for your plastic part that will hold up to steam?

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Dominoes
Sep 20, 2007



This is for the stove therm bobua posted about in the Electronics thread. I made it and am almost ready for a 1st production run. Enclosure is 3d-printed ABS. Ops testing shows the bottom to be getting a bit bent and deformed after being hit with steam repeatedly. I'm going to put an aluminum plate on it that matches the profile. Rubber would work too, but not sure how to machine it.

The machining-ABS part I posted is for a diff project, wherin in use a Hammond case and machine the top for the display cable, switch, RTD ports etc.

So, yes. Open to alternatives.

edit: Need aluminum plate etc for this; it printed fine, but seems to be getting damaged by the steam and perhaps releasing unsafe chemicals in the process.



Trying to troubleshoot some of the roughness etc here. (Maybe need to clamp the thing down better?) The slot being wonky I'm not sure about, but not a big deal since it's covered by a 3d-printed piece.

Dominoes fucked around with this message at 18:44 on Jun 5, 2021

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