First post. Thinking of trying my luck at CNC for machining aluminum. Looking at the Openbuilds C-Beam Platemaker. Thought this would be a good place to start to introduce myself to the world of CNC. With some of the modifications I have seen, looks like this could be turned into a nice little machine. Super Sized C-Beam Plate Maker Would like to make/modify molds for pouring jig heads for fishing. Molds halves would be ~ 4” x 10” x ¾”. Once I have mastered the C-Beam, will use the knowledge I learned to make plates and add electronics to convert my mini-lathe and mini-mill to CNC. Plan to buy the entire kit with all options. Thinking this would be the most trouble free path. Any thoughts, recommendations or other considerations would be appreciated. Dan
Welcome! We've got quite a few fishermen on the forum like @MStillman1966 who is going to be making lures according to this POST Look forward to following your journey!
I plan to make jig heads with mine too, but I just haven't got around to it yet. I have made several mounting plates for rod holders out of aluminum. I also made a custom "fish squish" board for pressing coho salmon fillets when making lox. Not the best picture, but it works.
Cool... I am assuming you have the Plate Maker. I already pour my own jig heads, but want to modify current molds and have ideas for new ones. This is example of my final product. Just need to place order.. doing a lot of reading right now before I pull plug. Will probably order everything Monday. -dan
Cool. Looks like a steelhead jig. My cnc is my own design similar to the Ox but I used large leadscrews rather than belts. It works great on aluminum.
Kit ordered. Everything except controller. Found a CNC Shield kit for $20 including Uno board. Thought I would play with that for a while. Excited...
Kit arrived last Friday. Haven't had a chance to open box. No place to work. Plan to clean out a space in garage then purchase work table. Will inventory all parts first. Received a Chinese and a real Uno. Also go a CNC Shield and speed board. Anyway, looking forward to getting started.
Finally have a few (4) days off and plan to start putting recently purchased C-Beam Plate Maker together. Box has been sitting in living room floor since it arrived almost a month ago. Going to make a little room in garage and open box to start inventorying parts. Question: If I want to document my build, do I just "Submit a Build" and go from there?
Ok... So I got everything unpacked this morning and checked ends of extrusions for square. I would say most of the pieces are cut with a slight angle in one direction. Suspect angle of chop saw is off. I added pic to show angle I'm talking about. (Don't think you can see the error in pic.) Do I proceed and see how build turns out or should I find solution for "squareness"? Dan
I would first check with a fixed square, instead of an adjustable square. (Many adjustables are not accurate enough.) And yes, I would correct for squareness and equal length before building.
OK, this project went on hold almost a year ago due to other things. Finally found some time to work on it again. All of the rails sent to a machine shop to be squared since ends were cut at an angle. Machine went together with no known issues following assembly video. Loaded GRBL 0.8 onto Arduino board and installed CNC Shield 3.0 board and drivers. Wired stepper motors. Using GRBL Panel, I was able to move all axis. Video went into discussing verifying GRBL settings. When I went to setting pages, rectangular settings area totally blank. No cells, no text, no numbers, nothing...totally blank. Selecting 'Get GRBL Settings' does nothing. Have tried two versions of GRBL Panel. Wrong GRBL Panel version for GRBL 0.8 maybe? Thoughts?
That is plan. Only concern is pin swap between Reloaded to latest version of GRBL and GRBL Panel. GRBL settings now showing up. I know that there is some changes to pin assignment for limit switches I will have to deal with later due to using older CNC Shield V3.0 board. Then again, plan to move to different controller and drivers in the future. Tried to set current limit on drivers, but Vref voltage did not seem to change. Voltage on all set to around 0.6v for 1.5 amp to motors which is where I wanted to start out. Will go to better drivers at a later date. Ran the Hello Word file for foam cutout. Had ticking noise in x-axis and X and Y moving in wrong direction. Added pre-load to x-axis by tightening collar and then set $3 to 5 to get axis moving in right direction. Adding a second set screw to collars is on to-do list. Ran file with and without marker pin. Motors sounded great to me. Happy where machine is at. Feel like I have made a milestone after a very long delay. Going to take a few weeks off to spend time with my wife and then see if I can actually cut some foam. Stay tuned.
Glad to see that seems to be sorted. Have a look at the Blackbox controller from Openbuilds - very good drivers and lots of protection features built in (eg for limit switches). Alex.
I second the Blackbox idea. However, if you are committed to the CNC shield, upgrade to the real one that was made for Grbl 1.1 for $20. It may save a lot of time and frustration. Arduino CNC Shield V3.51 - GRBL v1.1 compatible - Uses Pololu Drivers | eBay
Finally got a little time to play with this some more. First actual cut into MDF. Pleased with results. Going to check calibration next.
Finally have time to play around some more with Plate Maker. Retired today! LOL First thing was to verify calibration. Noticed right off that X and Y was only moving ~5MM when told to jog 10mm using GRBL Panel. Also went back and verified size of my Hello World cut compare to build video. It was half the size. All GRBL setting were set based on settings JPG in build software package. Changed resolution from 200 steps/mm to 400 steps/mm and now within 3/4 mm after moving 100 mm. Making assumption this has to do with difference in micro stepping. Have my controller set to 1/16 micro step. Seems to go back to same place when homed. Would like to find better way to verify calibration without "eye balling" it. Will work on that and resume calibration. Spent some time studying GRBL file to better understand GRBL commands. Seems rather simple. Going to play around with Estlecam. Need CAM software and since GRBL Panel is no longer supported will try control portion of Estlcam as well.
It looks like you are pretty dialed in, but here are a couple suggestions: Here is a simple 2 plus minute video - math included - on calibrating your cnc. If I were you I would go back to 1/8 microstepping and openbuilds suggests 199.1 steps.mm for their lead screws. Then fine tune it like in the video.
Took suggestions above and set micro stepping to 1/8. Sounds more "solid", if that makes sense, when moving axis. Calibrated X axis to 198.2 steps/mm, Y axis to 198.3 steps/mm and Z axis to 198.2 steps/mm. Next goal is to draw something, convert to gcode, cut and measure to see what I get. Stay tuned...
For the most accurate cut and measurement, do a rough cut leaving about 0.2-0.3 mm and then follow that with a finishing pass.
Been playing around with C-Beam a little more. After calibrating axis, Purchased Estlecam and created gcode file for a test pattern that has a 1" circle within a 2" square using TurboCad and Estlecam. (See attached pics.) When measuring dimensions of structures in y-axis direction I get 1.999" and 1.000" for square and circle respectively. This is very repeatable after 8 cuts and very pleased with results. However, results for measurements along x-axis are off 0.006" to 0.007" for square and circle respectively. This is repeatable as well. I can increase the steps/mm value and get measurement within same tolerances as y-axis, but throws the x-axis calibration way off when measured. When performing calibrations, I can do 100mm and 200mm moves multiple times and see no drift in starting and ending positions. Looking for ideas as to cause and ways to minimize error. First thing I am going to do is change cutting direction along y-axis. Second, going to do a rough cut followed by finishing cut as suggested above.
Was able to do a rough cut then finishing cut using defaults in Estlcam for a 2D drawing. No difference in small amount of error seen in X direction. Want to cut in Y-direction to see if this affects error but don’t see a way to change direction for 2D drawing In Estlcam. I do see how to do it in 3D cutting, but complicates simple 2D pattern. Now spending time creating 3D object and use masking to just cut the test pattern without completely machine object. At least that is what I will try next.
Was able to reduce my error by adding more preload on x-axis. Now 0.003” of error. Will look at anti-backlash next.
Wow! 0.003" seems pretty good. I bet your tolerances are better than mine. I have never really got into the weeds in checking. I have cut a lot of stuff and the parts have always worked the way I wanted so I have left well enough alone. However, I have never built too complicated of items. Now you have me curious what mine does.
I bought the Plate Maker as a CNC learning tool. Time has been an issue.. Sat unpacked for a year and started back with it last May. Have learned a lot. Smartest thing I did was send beams to a machine shop to square everything up. Using a simple test pattern for measuring 2" square and 1" circle 4mm deep. This does a rough cut then a finishing cut. Test file from Estlcam v11 attached. This does a rough cut then a finishing cut using a 1/" end mill. Would be curious what you get.
Decided to look into tramming and see how I could secure my dial indicator. Noticed the top wheels for z-plate where never adjusted Loose as a goose as some might say. Thought this was an ah ha moment and that this may have been my error in x-axis all along. Nope. After taking care of that issue, ran test pattern again. Error back up to 0.005". Noticed play in x-axis preload again. Set preload and error now 0.002". I can live with that. I think Open Builds should look into a threaded collar (like the threaded anti-backlash block) for setting lead screw preload and take load off of tiny set screw. Is there a suggestion box any where???
Yeah, pre-load on the screw is a bit of a muddle with all the force being on that little grub screw mashed against a threaded rod. Though, it works surprisingly well as long as the holding plate screws don't seize up (as steel in aluminum is likely to do). I've shim trammed my Z axis/spindle, sort of, but am deeply unsatisfied with that. Also, several of my eccentrics are at their limit, no more wear left. These are some of the reasons I'm moving to a more substantial machine - probably an Avid Pro.
