CNC hobbyist

[fatboyroy]

Anyone does CNC machining here? I ordered a small one that can do wood/lexan/aluminums and other softer metal to learn CAD programming/designing. Just looking for decent CAD software suggestion. Thanks

 

[Bruce]

I am wanting to get into CNC but currently do quite a bit of 3D printing.

I use Autodesk's Fusion 360 which is available free for personal use. Fusion 360 for Personal Use | Fusion 360 | Autodesk

Another low cost but high end option is EAA's free SolidWorks for members New EAA Member Benefit: Free SolidWorks

@tim h is a pro and likely has better recommendations.

 

[jdkaeser]

I use to design all my stuff in Adobe Illustrator and then exported it as a SVG and then imported it into Vectric Cut2D Pro which is the software that makes all the tool paths to generate the G Code needed by the CNC. Vectric was super easy to use for a beginner and affordable and they offer 3D versions as well. Check out the link below:

https://www.vectric.com/products/cut2d-pro?gclid=Cj0KCQjw8eOLBhC1ARIsAOzx5cFumtAF3wMT7bKnBt76Lpos_ptwkuNr_CSPPO__8lduxmCMJq5ZbbcaAipuEALw_wcB

 

[fatboyroy]

I am wanting to get into CNC but currently do quite a bit of 3D printing.

I use Autodesk's Fusion 360 which is available free for personal use. Fusion 360 for Personal Use | Fusion 360 | Autodesk

Another low cost but high end option is EAA's free SolidWorks for members New EAA Member Benefit: Free SolidWorks

@tim h is a pro and likely has better recommendations.

Thanks Bruce, I wont receive it til Friday and I have to assemble it. I will check the software you sent.

 

[fatboyroy]

I use to design all my stuff in Adobe Illustrator and then exported it as a SVG and then imported it into Vectric Cut2D Pro which is the software that makes all the tool paths to generate the G Code needed by the CNC. Vectric was super easy to use for a beginner and affordable and they offer 3D versions as well. Check out the link below:

https://www.vectric.com/products/cut2d-pro?gclid=Cj0KCQjw8eOLBhC1ARIsAOzx5cFumtAF3wMT7bKnBt76Lpos_ptwkuNr_CSPPO__8lduxmCMJq5ZbbcaAipuEALw_wcB

Thank you J I will watch the youtube and check it out.

 

[2kwik4u]

I've done a fair amount of toolpathing. I've been using Autodesk products for awhile. From a hobbyist standpoint Fusion 360 is strong enough to get everything you need from initial modelling to toolpathing.

Another tip, getting the toolpath is the easy part. Choosing and appropriate feed and speed isich more difficult. Check with you cutters manufacturer for recommended chip loading, then look online for the formulas to compute those. That'll get you close, fine tune from there.

Be sure to post pictures of your projects!

 

[GTBRMC]

I've done a fair amount of toolpathing. I've been using Autodesk products for awhile. From a hobbyist standpoint Fusion 360 is strong enough to get everything you need from initial modelling to toolpathing.

Another tip, getting the toolpath is the easy part. Choosing and appropriate feed and speed isich more difficult. Check with you cutters manufacturer for recommended chip loading, then look online for the formulas to compute those. That'll get you close, fine tune from there.

Be sure to post pictures of your projects!

Good tips here. Also, most failure modes I see in industrial CNC machining are, somewhat counterintuitively, workholding failures. Paths, geometry, tools, speeds and feeds are all important (as is conventional milling vs climb milling), but many don’t put enough thought into workholding.
Look up 3-2-1 location schemes and do your best to have your clamps’ line of action directly leading through the workpiece to the locators.

Interested in watching your progress.

 

[fatboyroy]

I've done a fair amount of toolpathing. I've been using Autodesk products for awhile. From a hobbyist standpoint Fusion 360 is strong enough to get everything you need from initial modelling to toolpathing.

Another tip, getting the toolpath is the easy part. Choosing and appropriate feed and speed isich more difficult. Check with you cutters manufacturer for recommended chip loading, then look online for the formulas to compute those. That'll get you close, fine tune from there.

Be sure to post pictures of your projects!

Thanks I will start with soft woods to get the hang of it I also ordered different type of bits but I have to wait for it. I understand the harder it is the slower the feed and proper bits is a must. Any suggestion on cooling liquid or do you just use water/oil?

 

[Bruce]

@fatboyroy, what CNC machine did you order?

 

[Can0n11]

I use Fusion360 because I get the educational licenses for free. There area a ton of YouTube videos out there that will teach you from the ground up on creating parts, and then will create tool paths(they call it manufacturing) which will generate a file for the cnc interface program. I am guessing your purchased CNC will have basic design software capabilities. I scratch built a CNC machine for our A&P students to use to create foam tool cutouts for their toolboxes (MPCNC - https://docs.v1engineering.com/mpcnc/intro/ ) using our shop 3D printer. When covid hit and I had to report to work (essential IT) and our college was 3D printing face shields. I used the CNC to make 2 additional 3D printers ( from V1's plans) to increase headband production. Basically, I used a 3D printer to make my CNC, and in turn I used my CNC to scratch build 3D printers. Cool stuff. I upgraded the table from the pictures posted as the table shown wasnt stout enough. I just dabble, GTBRMC and 2kwikforu definitely knows their stuff. Speed and feed. My CNC rendition is very basic, but it gets the job done for what we use it for.

 

[2kwik4u]

Thanks I will start with soft woods to get the hang of it I also ordered different type of bits but I have to wait for it. I understand the harder it is the slower the feed and proper bits is a must. Any suggestion on cooling liquid or do you just use water/oil?

For industrial applications I've used water, oil, and a water/air misting device. In general, you can cut without lubricant if you have good feed/speed choices, sharp cutters, and are using appropriate cutters for the job (roughing mills for material removal, finishing mills for final passes)

@GTBRMC is spot on as well, a good portion of the setup of CNC work is finding a good way to hold things. 321 clamps are great, I'm also a big fan of sacrificial "Soft Jaws" to hold irregular or sensitive pieces. Put the jaws on the vice, then model and mill out a profile that matches your work, essentially making custom clamps for desired workpiece.

Another quick tip. Don't make internal radiuses the same as your intended cutter. For example if you're using a .125 cutter, don't make your radius .125. make it slight larger (.130-.135) this will keep consistent tool loading as it traverse that shape. If the radii are the same you go from line contact between cutter and work to a plane (cylindrical shaped) and will either chatter like dammit or break the cutter.

There are SOOOOOO many more tips like that you will learn along the way. I've been making paths for a decade now and still learn new stuff every day.

 

[fatboyroy]

@fatboyroy, what CNC machine did you order?

This one it’s for beginner only all other brand are backlogged and will take 3 weeks shipping. Knowing most if not all is coming from China it will probably take longer due to bottleneck in California port.

 

[fatboyroy]

For industrial applications I've used water, oil, and a water/air misting device. In general, you can cut without lubricant if you have good feed/speed choices, sharp cutters, and are using appropriate cutters for the job (roughing mills for material removal, finishing mills for final passes)

@GTBRMC is spot on as well, a good portion of the setup of CNC work is finding a good way to hold things. 321 clamps are great, I'm also a big fan of sacrificial "Soft Jaws" to hold irregular or sensitive pieces. Put the jaws on the vice, then model and mill out a profile that matches your work, essentially making custom clamps for desired workpiece.

Another quick tip. Don't make internal radiuses the same as your intended cutter. For example if you're using a .125 cutter, don't make your radius .125. make it slight larger (.130-.135) this will keep consistent tool loading as it traverse that shape. If the radii are the same you go from line contact between cutter and work to a plane (cylindrical shaped) and will either chatter like dammit or break the cutter.

There are SOOOOOO many more tips like that you will learn along the way. I've been making paths for a decade now and still learn new stuff every day.

Thanks for the good tips! Im excited to learn this and eventually buy a better one to fabricate parts for my bike

 

[fatboyroy]

I use Fusion360 because I get the educational licenses for free. There area a ton of YouTube videos out there that will teach you from the ground up on creating parts, and then will create tool paths(they call it manufacturing) which will generate a file for the cnc interface program. I am guessing your purchased CNC will have basic design software capabilities. I scratch built a CNC machine for our A&P students to use to create foam tool cutouts for their toolboxes (MPCNC - https://docs.v1engineering.com/mpcnc/intro/ ) using our shop 3D printer. When covid hit and I had to report to work (essential IT) and our college was 3D printing face shields. I used the CNC to make 2 additional 3D printers ( from V1's plans) to increase headband production. Basically, I used a 3D printer to make my CNC, and in turn I used my CNC to scratch build 3D printers. Cool stuff. I upgraded the table from the pictures posted as the table shown wasnt stout enough. I just dabble, GTBRMC and 2kwikforu definitely knows their stuff. Speed and feed. My CNC rendition is very basic, but it gets the job done for what we use it for.

This is awesome stuff I think mine comes with GRBL basic controller or whatever it was but I will purchase a CAD and try all the free software available. That V1 plan is interesting thanks for sharing something I would consider in the future for sure.

 

[2kwik4u]

Here's some examples.

In this case the EE's had fully populated a board before they realized it was missing 3 holes. Took the giant block of plastic (Delrin I think) from the stock room and machined the circuit board shape into it, then drilled and tapped it to hold the board. Once I had the board held, then I could machine out the holes in the PCB they forgot to include. Using a rather large cutter here, and compressed air to keep it cool. I was running a pretty high spindle speed and very low travel speed as finished edge was more important than the time it took to remove the material.



Here's another neat project. The pieces were machined out of house, then anodized, then painted before we found out that the 3D model for the pump that went through the center had an error in the model. They wouldn't fit. I had to come in and change the angle every so lightly without completely destroying the piece. I used a TINY little end mill and only took out maybe .030 off one corner. We were on a tight deadline and couldn't remake the parts from scratch to fix the issue. Again, holding the piece was the fun part as I couldn't mar the finish at all, and I had (12) of them to "fix". I used some Delrin and dowels to make the placement repeatable, then some small pieces of aluminum and some blocking for hold downs. This allowed me to move pieces in/out easily and use the same program for each. Just used scrap paper as padding between the clamps and workpiece

Here's a quick video of it running: New video by Mike Dobrick



Both of those projects were on this machine. Haas ToolRoom Mill. It had a coolant system but was generally more of a mess than it was worth to use. Had tool holders, but was always a manual change over.



A tool you'll want to find and learn how to use is an edge finder. Tormach has a "cheesy" but extremely useful video on it. This helps find the edges (as the name implies), and by finding those edges and using the DRO on the machine, you can set your zero points and offsets in the machine with excellent accuracy.

When setting the Z-Height of your tool for offsets, I use a piece of scrap paper, then jog gently downwards until the paper will just not slide between the workpiece and the tool. I would go by .001 increments until it touches, back it off a .001, then go by .0005 increments until it touches. Again, it's not perfect, but it's close enough. If you get into some really high tolerance stuff in the future, there are strategies to "sneak up" on your final profiles to get the exact tolerance you want.

All of this is fun, and I felt like I had a great grasp on CNC programming......then I got put in charge of a 6-axis robotic welder last year. Cheese and Flippin' Rice that is a completely different ballgame. You have to get real good real quick at coordinate system transformations, and spatial/time relationships to make that thing work worth a damn. With that said, now that I understand and work with it often, I'm absolutely DYING to put a router head on it, and make something REALLY cool looking. Can you imagine the cool shapes you could make with that kind of tool head positioning and access?!?!?

Here's Big Bird while I was programming it last fall.


If you can't tell I'm a sucker for mechatronics in general. CNC programming is just a small portion of that field. I could talk about this stuff for days and days and days. Maybe even more than boats!

 

[fatboyroy]

Here's some examples.

In this case the EE's had fully populated a board before they realized it was missing 3 holes. Took the giant block of plastic (Delrin I think) from the stock room and machined the circuit board shape into it, then drilled and tapped it to hold the board. Once I had the board held, then I could machine out the holes in the PCB they forgot to include. Using a rather large cutter here, and compressed air to keep it cool. I was running a pretty high spindle speed and very low travel speed as finished edge was more important than the time it took to remove the material.

View attachment 166167

Here's another neat project. The pieces were machined out of house, then anodized, then painted before we found out that the 3D model for the pump that went through the center had an error in the model. They wouldn't fit. I had to come in and change the angle every so lightly without completely destroying the piece. I used a TINY little end mill and only took out maybe .030 off one corner. We were on a tight deadline and couldn't remake the parts from scratch to fix the issue. Again, holding the piece was the fun part as I couldn't mar the finish at all, and I had (12) of them to "fix". I used some Delrin and dowels to make the placement repeatable, then some small pieces of aluminum and some blocking for hold downs. This allowed me to move pieces in/out easily and use the same program for each. Just used scrap paper as padding between the clamps and workpiece

Here's a quick video of it running: New video by Mike Dobrick

View attachment 166176

Both of those projects were on this machine. Haas ToolRoom Mill. It had a coolant system but was generally more of a mess than it was worth to use. Had tool holders, but was always a manual change over.

View attachment 166177

A tool you'll want to find and learn how to use is an edge finder. Tormach has a "cheesy" but extremely useful video on it. This helps find the edges (as the name implies), and by finding those edges and using the DRO on the machine, you can set your zero points and offsets in the machine with excellent accuracy.

When setting the Z-Height of your tool for offsets, I use a piece of scrap paper, then jog gently downwards until the paper will just not slide between the workpiece and the tool. I would go by .001 increments until it touches, back it off a .001, then go by .0005 increments until it touches. Again, it's not perfect, but it's close enough. If you get into some really high tolerance stuff in the future, there are strategies to "sneak up" on your final profiles to get the exact tolerance you want.

All of this is fun, and I felt like I had a great grasp on CNC programming......then I got put in charge of a 6-axis robotic welder last year. Cheese and Flippin' Rice that is a completely different ballgame. You have to get real good real quick at coordinate system transformations, and spatial/time relationships to make that thing work worth a damn. With that said, now that I understand and work with it often, I'm absolutely DYING to put a router head on it, and make something REALLY cool looking. Can you imagine the cool shapes you could make with that kind of tool head positioning and access?!?!?

Here's Big Bird while I was programming it last fall.
View attachment 166178

If you can't tell I'm a sucker for mechatronics in general. CNC programming is just a small portion of that field. I could talk about this stuff for days and days and days. Maybe even more than boats!

Nice industrial grade machinery you've got! From the video is the center hole where you calibrate spindle location so it knows the location on where to shave the inner edge?

Edit: Nevermind the question I just watched the edge finder video lol

 

[2kwik4u]

Nice industrial grade machinery you've got! From the video is the center hole where you calibrate spindle location so it knows the location on where to shave the inner edge?

The center hole was a relic from a previous attempt to hold something else. The base delrin was scrap I pulled from the closet.

Best practice is to set your offsets for both work, tool and world from easily locatable edges. Do one axis at a time. The more measurements you have to take "by hand" the more your error will stack up. This starts all the way back at the programming and setup of the code. Choose convenient and easily measurable points as your (0,0,0) or "home" locations. The better you are at choosing these locations, the easier the transition will be from the virtual world to the physical. That transition from virtual world to physical world is one of the hardest parts of the whole process.

 

[fatboyroy]

The center hole was a relic from a previous attempt to hold something else. The base delrin was scrap I pulled from the closet.

Best practice is to set your offsets for both work, tool and world from easily locatable edges. Do one axis at a time. The more measurements you have to take "by hand" the more your error will stack up. This starts all the way back at the programming and setup of the code. Choose convenient and easily measurable points as your (0,0,0) or "home" locations. The better you are at choosing these locations, the easier the transition will be from the virtual world to the physical. That transition from virtual world to physical world is one of the hardest parts of the whole process.

Thank you I will probably pick top left of the cnc working area as my zero, like printing paper always have to be on top left of the printer.

 

[Bluewater272]

Good stuff in here. I've been thinking of building my own CNC with 3D printed parts, my only hangup is dedicating space to one as I'd like a fairly large bed. Need to noodle about storage, perhaps I can arrange some sort of lift that would lift it up to the garage ceiling, and when in use could drop down onto my rolling workbench.

 

[2kwik4u]

Good stuff in here. I've been thinking of building my own CNC with 3D printed parts, my only hangup is dedicating space to one as I'd like a fairly large bed. Need to noodle about storage, perhaps I can arrange some sort of lift that would lift it up to the garage ceiling, and when in use could drop down onto my rolling workbench.

Big thing to keep in mind on DIY setups is the stiffness and mass required when you get into metals. The forces on the spindle and table can be significantly high when machining metal, and the mass is required to keep vibrations and associated NF resonance at bay. If you want to get serious about doing CNC on metal it's not overly difficult to convert an old bridgeport over to CNC control. In the process you will have to machine some parts from metal on the bridgeport itself, which IMO is experience every single CNC operator should have. I helped a friend convert one over many years ago, and the electronics aren't significantly difficult, and you can get some pretty accurate parts from it in the end without breaking the bank.

Storage, shop space, and power requirements push it somewhat out of "hobbyist" level though IMO.

If you're going to stick to wood/plastic and LIGHT LIGHT LIGHT metal work then you can probably 3D print the parts you need to hold the frame togethor.

I've had my eye on a Snapmaker for awhile for this very reason. All CNC machines operate on the same G-Code basis, as well as cartesian coordinate systems. Having something like the Snapmaker with interchangeable heads really opens up the possibilities of what you can make with a single machine. Laser engraving, light CNC wood carving and and machining, and 3D printing really cover a LOT of ground in the maker space. If you could add a drag knife for vinyl cutting you get a lot more space covered. At under $2k to get started, there's a lot of value in something like this