Okay now that's really cool and very educational. I'm a newb in the cnc world and my big take away is the g-code programming. I've asked about this on a couple other sites and was told you can't do that, g-code is dumb and just reads one line of commands at a time till the end. This really opens doors for doing projects like this where you just want to do it and not spend time modeling it in software first. Thank you James 👍🏻👍🏻
Only addition to the G code I would put to prolong the life of the tool is a small retract to Y- at the end of the stroke and return to cut at the top. Just something small like 0.2 mm with an incremental move, so that the tip of the tool doesn't drag on its way up.
Totally awesome Video - James! Thank You! I run Mach3 on all my CNC machines. I'm also an old G-coder (athough I use it less and less with the advent of good and inexpensive CAM). I love this kind of video. You used CAD, G-code and a lot of inventiveness. Well done! Please keep these types of videos coming.
Even as a manual hobby machinist I learn things from your CNC oriented videos and appreciate your contribution to this hobby. As a general machining observation I didn't see any radius on your keyway broaching tool. Good machining practice is to provide a corner radius for key slots. I was taught that machining a sharp inside corner is essentially building in the beginning of a stress crack. I realize you are testing the codes and process here but I think the aluminum grinder part you made in the previous video was a real part. Consider putting a corner radius on the broaching cutter for future projects. Though there shouldn't be impact involved with the grinder part there could be extreme vibration loads if a wheel fails.
I love that you’re doing hand-written g-code. When the maker space I used to frequent first got a CNC mill, I started exploring that, and seeing all the codes that were available, and making plans for doing stuff like what you show here… and then people just started doing things in CAD and sending generated g-code over… and they made some cool parts that way, but it seemed so much less fun. 😊
Its a good skill to have in your back pocket. For simple parts its nice to be able to just walk up the the controller, press buttons for two minutes, and have something running.
I had to cut a key way and remembered this video. I used your code and it worked great. Except I had trouble getting it to go past the first subroutine. I had to put one more line of code at the end of just "%". It ran fine after that. Great job and keep up the great vids.
I just bought a Grizzley G0704 mill (for $800) and I thought I would go back and look at some of your older videos using the G0704 just to get an idea of the capabilities of the mill. I'm not planning on CNCing the mill because I already own a Denford Triton Pro VMC but I'm going to use it to convert my Gearhead round column mill to a square column. I just wanted to get a feel for how well the G0704 works and how stiff/precise it is. I love your videos and always appreciate your input to the home machine shop craft.
Very nice macro program for keyway cutting. We use a very similar code such as yours. But I would like to make a suggestion if I may. Our code retracts the tool out of the slot before returning to Z start position so the tool does not drag backwards on the material. We use carbide keyway cutters an they chip if dragged. Probably not a problem with hss tool as much. I wanted to mention you may have forgot to specify your tool needs to be a little wider than half of the keyway width so the two X moves will cover it.
Gears! Gears! Gears! Which is a fine excuse to make a little 4th axis, if not a full blown cnc spindle position upgrade. Did you measure the steel keyway, to find out if there was any taper due to tool deflection?
Congratulations James : this keyway is perfect and your method impressively convenient. The chips look beautiful especially in steel. I suppose than the honing is donne very carefully😉
James; Just came across this video. Noticed the GCODE assumes that the broach width is less that the keyway width and at least half the width of the keyway. This is not a criticism, but I've always been noted for my robust code.
Great videos. I'm not usually a fan of videos longer than about 5 minutes but all of these I've watched have been well worth the investment in time and interesting to watch. Thanks for taking the time and trouble to make and share them. I have one question, though. You mention in a couple of them that you have measured "just with the caliper". In my amateur and novice ignorance, I have always thought that the caliper was the good way to measure. When you don't "measure just", what do you measure with and, if you don't mind, why?
It all depends what you're trying to accomplish. A caliper will get you within .001" or .002", depending on the exact geometry and your technique. That's fine for loose fitting parts. But if you're making parts that have to assemble with a press fit or a close siding fit, that isn't precise enough. A good micrometer can measure to within .0001" or .0002". Usually, though, I measure as precisely as I can, even when it isn't justified, just because I can. :)
Google "indicol dial test indicator holder". Mine is a cheap import, and it uses nylon (or UHMW?) washers under the adjustment knobs. They don't hold their position well. I've been thinking about rebuilding it or getting a better one.
Hi Sir, I am very please with your gcode and your effort you put into helping your viewers. I went through your Gcode and formulas and I noticed the width of the cutter must at least be 1/2 of the key width (min value) and of course a maximum cutter width = the key width. Please correct me if I am wrong ? I studied and ran the gcode and the X wiggles left and right thus the cutter width cannot be less than 1/2 the key width or else the broach will miss the center area of the key width.
Sir, i noteced the first stroke does nut cut anything, it mearly plunges and retract at the starting y position, however consequent stroke cuts by the amount if deoth of cut. Please correct me if i am wrong?
@@Clough42 Hi, I just went to use this for larger keyways, and it appears as though it really only suits keyways which are less than, or equal to double the width of the broach. for example: If i want to broach a 36x20 keyway (t2=8.4mm) using a 10mm wide broach, using this method I would end up with 2 slots either side of the centreline separated by the keyway width, minus double the thickness of the cutter width. in this case a 16mm uncut section in the middle. once I fix it and get it working I'll send you the code, or post it on github.
A little late for me to comment but why not enter the values from the machine guide in metric and let the gcode convert to imperial if needed. You could have a switch that is a y/n to convert. That way you do no math. I'm a retired programmer.
Okay now that's really cool and very educational. I'm a newb in the cnc world and my big take away is the g-code programming. I've asked about this on a couple other sites and was told you can't do that, g-code is dumb and just reads one line of commands at a time till the end. This really opens doors for doing projects like this where you just want to do it and not spend time modeling it in software first.
Thank you James 👍🏻👍🏻
Only addition to the G code I would put to prolong the life of the tool is a small retract to Y- at the end of the stroke and return to cut at the top. Just something small like 0.2 mm with an incremental move, so that the tip of the tool doesn't drag on its way up.
Yeah, that's a good idea. I keep meaning to add that, and forgetting.
Totally awesome Video - James! Thank You! I run Mach3 on all my CNC machines. I'm also an old G-coder (athough I use it less and less with the advent of good and inexpensive CAM). I love this kind of video. You used CAD, G-code and a lot of inventiveness. Well done! Please keep these types of videos coming.
Even as a manual hobby machinist I learn things from your CNC oriented videos and appreciate your contribution to this hobby. As a general machining observation I didn't see any radius on your keyway broaching tool. Good machining practice is to provide a corner radius for key slots. I was taught that machining a sharp inside corner is essentially building in the beginning of a stress crack. I realize you are testing the codes and process here but I think the aluminum grinder part you made in the previous video was a real part. Consider putting a corner radius on the broaching cutter for future projects. Though there shouldn't be impact involved with the grinder part there could be extreme vibration loads if a wheel fails.
this channel deserves subscribers
Feel free to tell all your friends. :)
I love that you’re doing hand-written g-code. When the maker space I used to frequent first got a CNC mill, I started exploring that, and seeing all the codes that were available, and making plans for doing stuff like what you show here… and then people just started doing things in CAD and sending generated g-code over… and they made some cool parts that way, but it seemed so much less fun. 😊
Its a good skill to have in your back pocket. For simple parts its nice to be able to just walk up the the controller, press buttons for two minutes, and have something running.
I had to cut a key way and remembered this video. I used your code and it worked great. Except I had trouble getting it to go past the first subroutine. I had to put one more line of code at the end of just "%". It ran fine after that. Great job and keep up the great vids.
I just bought a Grizzley G0704 mill (for $800) and I thought I would go back and look at some of your older videos using the G0704 just to get an idea of the capabilities of the mill. I'm not planning on CNCing the mill because I already own a Denford Triton Pro VMC but I'm going to use it to convert my Gearhead round column mill to a square column. I just wanted to get a feel for how well the G0704 works and how stiff/precise it is. I love your videos and always appreciate your input to the home machine shop craft.
Very nice macro program for keyway cutting. We use a very similar code such as yours. But I would like to make a suggestion if I may. Our code retracts the tool out of the slot before returning to Z start position so the tool does not drag backwards on the material. We use carbide keyway cutters an they chip if dragged. Probably not a problem with hss tool as much. I wanted to mention you may have forgot to specify your tool needs to be a little wider than half of the keyway width so the two X moves will cover it.
This is a pretty cool project, nice job! Good on ya for sharing the macro code and explaining it in a really easy to understand manner.
Whatever ended up happening to the hand scraper project? I’m trying to learn the basics and I would love to see your process of learning how to do it!
Ver nice sir, thank you for your contribution to our knowledge. Cheers from Malaysia
Gears! Gears! Gears! Which is a fine excuse to make a little 4th axis, if not a full blown cnc spindle position upgrade.
Did you measure the steel keyway, to find out if there was any taper due to tool deflection?
Just with calipers, and I didn't detect any taper in width or depth. The tool was very sharp; I think that helps a lot.
Great variable program!
Congratulations James : this keyway is perfect and your method impressively convenient. The chips look beautiful especially in steel. I suppose than the honing is donne very carefully😉
Thank you! After grinding, I did hone it on a ruby stone. :)
3 years later, how much have you used the generic code? It's the first time I've seen GCode run as a logical language. Very cool.
Not gonna throw another loop in there, in case it takes more than 2 passes to make it across the entire width?
James; Just came across this video. Noticed the GCODE assumes that the broach width is less that the keyway width and at least half the width of the keyway. This is not a criticism, but I've always been noted for my robust code.
Good luck if your keyway is narrower than the tool.
Great videos. I'm not usually a fan of videos longer than about 5 minutes but all of these I've watched have been well worth the investment in time and interesting to watch. Thanks for taking the time and trouble to make and share them. I have one question, though. You mention in a couple of them that you have measured "just with the caliper". In my amateur and novice ignorance, I have always thought that the caliper was the good way to measure. When you don't "measure just", what do you measure with and, if you don't mind, why?
It all depends what you're trying to accomplish. A caliper will get you within .001" or .002", depending on the exact geometry and your technique. That's fine for loose fitting parts. But if you're making parts that have to assemble with a press fit or a close siding fit, that isn't precise enough. A good micrometer can measure to within .0001" or .0002". Usually, though, I measure as precisely as I can, even when it isn't justified, just because I can. :)
This is awesome.
Could you please share the details of the machine.
It's a Grizzly G0704 hoss CNC conversion.
Haha a DIY shaper love it
James, I've seen in other videos you use VS Code. Is there a specific extension you prefer to use for creating/editing G-Code?
@Clough42 nice video! Did you make the dial indicator fixture or is that something I can purchase somewhere ? It looks pretty handy.
Google "indicol dial test indicator holder". Mine is a cheap import, and it uses nylon (or UHMW?) washers under the adjustment knobs. They don't hold their position well. I've been thinking about rebuilding it or getting a better one.
Hi Sir, I am very please with your gcode and your effort you put into helping your viewers. I went through your Gcode and formulas and I noticed the width of the cutter must at least be 1/2 of the key width (min value) and of course a maximum cutter width = the key width. Please correct me if I am wrong ? I studied and ran the gcode and the X wiggles left and right thus the cutter width cannot be less than 1/2 the key width or else the broach will miss the center area of the key width.
Yes. That is correct. You could add another stroke in the middle, or just use a wider cutter.
@@Clough42 thank you for the cinfirmation and the suggestiin. Cheers
Sir, i noteced the first stroke does nut cut anything, it mearly plunges and retract at the starting y position, however consequent stroke cuts by the amount if deoth of cut. Please correct me if i am wrong?
Can we cut internal gears?
Excellent effort.
Awesome stuff, now to make it metric... I dunno why you guys stick to that imperial system.
Because the hand wheels on my machines are marked with Imperial graduations. I use metric exclusively with my 3D printers.
Clough42 yeah thats a fair reason...
@@Clough42 Hi, I just went to use this for larger keyways, and it appears as though it really only suits keyways which are less than, or equal to double the width of the broach. for example: If i want to broach a 36x20 keyway (t2=8.4mm) using a 10mm wide broach, using this method I would end up with 2 slots either side of the centreline separated by the keyway width, minus double the thickness of the cutter width. in this case a 16mm uncut section in the middle. once I fix it and get it working I'll send you the code, or post it on github.
Very Nice!
Very good video's, keep up the awesome work. To bad I run an acorn rf45 mill, g-code is posted in wrong format for me, still very cool
Wear eye protection! Even if just to set an example.
Seconded.
Impressive uk
A little late for me to comment but why not enter the values from the machine guide in metric and let the gcode convert to imperial if needed. You could have a switch that is a y/n to convert. That way you do no math. I'm a retired programmer.
Sooo... if I just pick a key width larger than twice the cutter width, I can get two keyways for the price of one...? Boooyah...! ;)))