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OpenBuilds LEAD CNC

Discussion in 'CNC Mills/Routers' started by MaryD, Nov 20, 2018.

  1. joe williams

    joe williams Well-Known
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  2. CreemCheese

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    Getting so close to ordering one of these, trying to make sure I order everything I need. Does it come with the router mount?
     
  3. Batcrave

    Batcrave Journeyman
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    It comes with the router mount if you're using the default Dewalt DWP611, or something close enough in size that it can be shimmed to fit. If you're deliberately making life difficult for yourself and doing something stupid like ordering a big, shiny, 80mm water-cooled spindle, you're on your own. Me, I'm all about the stupid, so I'm looking at probably bootstrapping my way in - hose clamps on a Frightening Harbor trim router to cut a temporary spindle mount out of wood, then using that on the big spindle to cut a proper mount from aluminum.

    If you want a pretty much out-of-the-box paint-by-numbers setup, you can probably just check off all the order page options (steppers, xPro, wiring kit, PSU, router) and be confident that you've got everything you need except the spoilboard (and a drill/impact driver/screwdriver-and-serious-muscles for the self-threading screws on the endcaps... and maybe a fresh blade on your boxcutter/xactco/pocket knife to get through all the packing). If you're planning to make any changes, or DIY any aspects of the project, we can probably give better advice if you describe what you have in mind.

    One thing that's good to have that doesn't seem to be included - or even sold on the parts store - is an E-stop button (I have one like this from Amazon, but you can find them for even cheaper).

    Personally, aside from the spindle and extra rails to make the build narrower, I'm also recycling the steppers, switches, wiring, and electronics from my previous build, so I pretty much just got the base kit with the drag chains, LED ring, and slot covers. Of course, I completely forgot about the hardware to mount the drag chain and switches. No one pointed out that I was missing a shorter replacement for the non-structural 20x20 rail that acts as a wire rack behind the gantry, either. But if you describe your plans, we can at least try to give decent advice.


    -Bats
    (well... as long as you define "try", "advice", and "decent" loosely enough...)
     
  4. CreemCheese

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    Thanx bats. This is my first cnc, so I'll build it in stock form and use it for a while before making any changes.
    I'm probably going to use the Makita trim router and shim it into the DeWalt mount. Didn't think about the drag chain, I should probably add that on too.

    Going to be getting the electronics and wiring off eBay, but I know my way around most of that stuff.
     
  5. Batcrave

    Batcrave Journeyman
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    Unlike me, you might want to skim the wiring video before placing your order anyhow - it'll give you some idea of how they intended for things like the drag chain & limit switches to be mounted, and you may find yourself wanting to toss some extra screws, brackets, t-nuts, or those little limit switch mounting plates in with your order. [ edit: ooo! and slot covers! can't have a flashy new machine with your wires hanging out all over the place... I kinda wish I'd gone for a Workbee instead, so I could've used black rails with yellow slot covers ]

    Actually, you might want to toss an extra pack of M5 T-nuts into your order anyhow. Most of the parts & hardware are great, but they've clearly got some QC issues with the threading on those nuts. I've seen a couple other people mention problems, and I ran into at least a half dozen that were unusable until I chased/retapped the threads. Openbuilds is really quick about sending out replacements for missing/damaged bits (thanks, Rachel!), but it's much easier if you can just swap in a good one from a pile of extras and not worry about it.


    -Bats
    (take my advice - I'm obviously not using it for anything)
     
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  6. CreemCheese

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    How long of drag chains do I need? The wiring kit shows 2 different sizes, but I assumed it'd be 1000 each for x and y

    I'm torn on the light ring. It looks great in every sense, except that I was going to use 36v power supplies. So I'd either need a small supply just for the lights or have to find a voltage reducer.
     
    #156 CreemCheese, Dec 31, 2018
    Last edited: Dec 31, 2018
  7. Batcrave

    Batcrave Journeyman
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    The parts list shows "2 Drag/Cable Chain - 1000mm" which is what I (like you) assumed it would use. The store page is definitely a little confusing, but it looks like they've just recycled the same image for all of the different machines' wiring kits - presumably borrowed from one of the machines with asymetrical axes.

    Speaking of which, for anyone thinking about changing the dimensions of their Lead by replacing rails, very carefully check the sketchup model and/or watch the assembly video, as the parts list doesn't accurately list the lengths of all of the rails. It lists five 20x40x1000mm V-rails, while the kit actually uses three 985mm and two 962mm rails (one with a tapped hole on one end), so your custom build might not end up with quite the dimensions you're expecting.

    Not paying close enough attention to the model led me into an entirely different problem. In cutting the X axis in half, from 1000mm to 500mm, I was thinking I'd get 730mm/2=365mm or 13.4" travel, rather than the actual 730mm-500mm=230mm, for a measly 9" of X. I don't have much choice but to run with it for the moment, but sooner rather than later I think I'm going to have to take a saw to the original full-length rails in hopes of getting something more reasonable.

    Same problem here, since I'm using the 36V PSU from my previous build. I thought about trying to misuse the 24VDC output on the spindle VFD, but, while they don't list the current draw anywhere, I can't imagine running a dozen white LEDs without exceeding the 100ma cap on it. Sticking some resistors in front of the LED ring was another option, but it looked a little iffy and I didn't want to deal with troubleshooting more involved circuits. In the end I decided to just order a cheap 24VDC wall wart, figuring I can plug it in next to the PSU.

    Of course, now it occurs to me that I probably should've gotten a larger transformer, as I'm also going to need to power a couple 12VDC fans on a radiator for the spindle. Oops.


    -Bats
    (Oops! It shall be my battle cry!)
     
  8. CreemCheese

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    Well, life got in the way again. May be a while, but I'm still planning on getting one. In the meantime I get more time to dream and scheme.
    A pc power supply might be the way I go, can use a -12v and +12 to get the 24v needed, LEDs should be a minimal current draw, then have some 12v and 5v for fans and other accessories. I'll still use the 36v for the steppers.
     
  9. Batcrave

    Batcrave Journeyman
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    Curse you, life! CURSE YOOOOOOU! :vainlyshakingfistatsky: (we need that smiley, btw).

    I completely understand, though... this upgrade was supposed to happen a year or two back, for me, and almost didn't happen this time around, either.

    You might be able to get away with it, as long as the current draw is low enough (I'm guessing around 150mA, but it's been a good few years since I've done much with electronics, and even then my math was spotty at best), but it probably depends on the PSU. A lot are only rated for ~300mA on the -12V rail, and, if it's anything like the other rails, I wouldn't count on ever getting the actual nameplate capacity. It seems like an awfully big and noisy way of going about it, though (and I say this as someone who spent a couple years running the prior contraption off 24V from a pair of ATX PSUs ziptied together with hacked grounds).

    It would be nice to know what the real requirements are, though... Any chance Mark or someone over there could give us an official current figure for the ring?


    -Bats
    (Mark, or someone over there... or someone not over there who's at least halfway competent. Maybe even a quarter of the way. Someone, like, for example, not me.)
     
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  10. Natesbox

    Natesbox New
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    Has anyone ran this machine with bCNC? I'd like to try a more advanced control software, but want to make sure I set the program up correctly. I have not ventured outside openbuildscontrol and just want to make sure I'm on the right track.

    Do I simply need to configure Tools -> Config? With the bed size?
     
  11. Natesbox

    Natesbox New
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    Got it working!
     
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  12. ADW_01

    ADW_01 New
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    Just curious, how do you like bCNC over the openbuilds control? What about it would you say is better? Thinking about giving it a try myself.

    Thanks
     
  13. Batcrave

    Batcrave Journeyman
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    So the UnLEADed machine is finally together - or rather back together in its new half-width configuration (that will likely end up pulled apart again into something more like a 2/3 or 3/4-width version), the initial build only taking about ten hours (including several hours of swearing and looking for rails that weren't there) shortly before the holiday - and has been moved to its semi-final home (although it'll still need a new table, eventually).
    In the current form, I think that center 1m 20x40 rail is probably superfluous, but at least this saved me finding anywhere to store it.
    IMG_20181229_212848.jpg IMG_20181229_221105.jpg

    [ edit: conveniently enough, this ultra-thin configuration means that a $3 "Bullnose MDF Shelving Board" from the Homeric Despot is nearly the perfect size for a spoilboard, which, for reasons which remain obscure, is drastically cheaper to buy than equivalent footage in their other MDF panels ]

    It still doesn't have all the endcaps reattached, and the tangled wiring is still temporary & lacking drag chains or slot covers, at least until I get around to making some mounts for the limit switches. My previous contraption was such a mess that I didn't feel bad about just drilling & tapping holes to stick in screws or bolt on chunks of scrap metal wherever it was convenient, but the new build's so nice & clean & shiny (curse you, Industrial Black! curse you and your sleek immaculate beauty) that I feel obligated to do it right, so I'll probably be borrowing shamelessly stealing Openbuilds' limit switch mounting plate design as my first experiment in cutting aluminum.

    Of course, that requires getting to the point of cutting aluminum, which means getting the big spindle mounted - and it is big (there'll be another post for that later, but in the meantime, take my word for it - and don't even consider the larger 2.2kW spindles unless you're using a significantly heftier machine) - which means cutting a temporary mount using something else...

    IMG_20190101_171822.jpg

    I feel dirty. And not in a good way, either... polluting my nice, beautiful, brand new machine with a filthy old $25 Harbor Freight trim router (and a rather ridiculously thick stack of shims)? Bleh.

    For the moment I'm mostly focused on tuning the motors in Mach3, since, despite using almost entirely the same electronics, this is a pretty drastic change from the build they were previously attached to.

    I've been particularly running into trouble with the Z axis - it doesn't seem like it's missing steps so much as missing entire commands, and I haven't been able to figure out whether it's a problem in the motor tuning, or in my auto-zero script. The fact that the interface still shows the movements, and that it only happens sporadically makes me think it's not the script, but I still haven't been able to isolate any other cause. It doesn't seem to be tied to speed, and acceleration isn't looking likely either. The fine tuning trimpots on the Gecko G540 don't seem to do much outside of extremely low speeds, and the G250X drivers it uses are supposed to be practically immune to midband resonance (which, because that tends to be speed related, I'd pretty much ruled out anyhow). The obvious next step in troubleshooting was to put off dealing with it by making long-winded progress posts here.


    -Bats
    (thanks for helping me not get anything done)
     
    #163 Batcrave, Jan 2, 2019
    Last edited: Jan 2, 2019
  14. Rob Taylor

    Rob Taylor Master
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    If you're not procrastinating by posting updates on OpenBuilds, are you, in fact, accomplishing anything at all?
     
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  15. GrayUK

    GrayUK Openbuilds Team Elder
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    Bats doesn't Procrastinate, he just ........ thinks alot, about lots of things. :D
    However, he does get more done than myself.
    But, I don't procrastinate, I'm just plain lazy! :banghead:
     
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  16. CreemCheese

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    Bats you're not putting off troubleshooting, you're spreading knowledge through well thought out posts
     
  17. Batcrave

    Batcrave Journeyman
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    I wouldn't know... if I wasn't not-accomplishing anything, I wouldn't have anything to post about.

    -Bats
    (...I think?)
     
  18. Batcrave

    Batcrave Journeyman
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    Well thought out posts?

    *blink*

    Where? Where?

    -Bats
    (no, really... this sounds like something I should read)
     
  19. Batcrave

    Batcrave Journeyman
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    Most of which are completely and utterly unrelated to whatever it is I'm theoretically trying to get done.

    Considering the sheer amount of time it takes me to get any of it done (and/or to actually do any of it), I'd feel better if I were just being lazy instead.

    On the brighter side, I did manage to solve a problem with the auto tool zero script that's been bugging me for years & often requiring multiple attempts to get a clean result. It seems there was a race condition between the system running the G31 probe and Mach3's VBscript engine reading the result, so some unpredictable percentage of attempts would fail.

    Of course, that wasn't the part that had me most concerned, but now I'm having trouble getting the real problem - the missed steps - to manifest. This would be a good thing, if I had any idea why they were/weren't happening in the first place. I'd much rather get the problem identified and resolved now, rather than having it manifest midway through an involved piece in some sort of unforgiving material.


    -Bats
    (the problem, however, would much rather hide in the shadows until the tail end of a 12hr long two-sided program on an unusually large and expensive block of material, shortly after the eighth toolchange, to a particularly fragile and expensive tool. the problem likes doing things like that.)
     
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  20. Rob Mitchell

    Rob Mitchell Well-Known
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    What are you all using for stepper settings (steps per rev) for this lead screw mill.
     
  21. Natesbox

    Natesbox New
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    Well for starters, this is my first CNC router and both the Openbuilds cam and machine control software both worked great (mostly) and allowed me to jump in without too steep of a learning curve. This is key. Using Inkscape (also free!) along with the Openbuilds software has produced good results for me. I was very happy that I was able to run the machine my linux laptop, as well as windows.

    Once you get past that though, I ran into issues with the control software doing odd things, locking up etc.. When I switched to my windows CNC PC it was frustrating that sometimes the openbuildscontrol.exe would get stuck and the process couldn't be killed no matter what, yes even as Adminstrator, "Access denied". I think it had something to do with it holding the com port open. A reboot seemed to be the only cure. Additionally, I'm personally not a big fan of the websocket setup in the software, it certainly makes things simple since the cam software will transfer your gcode right to the control software. But you have to be connected to the internet to use the cam software, and I just don't like having my machines with a connection to the internet. You can save the gcode and load it into the control software as well, so you aren't completely forced to have a connection. I'll also add that from my experience the cam software can get bogged down if there are a lot of toolpaths and/or a slow pc. Last but not least I just want to experiment, learn and get the most out of my machine. These are the reasons I started investigating other options.

    I want to say that in a nutshell my experience with the OpenBuilds software has been generally positive and allowed me to start using my machine without screwing something up. I have been watching the changelog and the devs are definitely making updates and I would be surprised if most of the issues I encountered will be worked out. It's great software to get you started!

    As for bCNC, I can't give you any opinion of substance on it as of yet. All I've done is loaded up my machine settings and jogged the machine around. It's certainly for a more advanced user and has some really cool capabilities. Additionally, I read that the developers of grbl do their testing and validation using bCNC so that seems like a decent endorsement to me. It seems to do a ton of stuff, but as for now for me how good it works for me remains to be seen, but so far so good!
     
  22. Batcrave

    Batcrave Journeyman
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    Using a dial indicator and Mach3's axis calibration (which moves the axis a given distance, and compares it to your actual, measured movement) I've current got mine set to:
    X: 6280.339396
    Y: 6240.748377
    Z: 6286.505901

    ...although I suspect there'll also be a fair bit of variation from one machine to the next, and obviously most of the decimals are beyond the actual measurable precision and/or repeatability even on mine. Probably no less than I deserve for offloading my math onto computers.

    I've also been meaning to ask what sort of rapids & acceleration other people have been using. I've got X & Y capped rather arbitrarily at 300ipm, with 75in/s^2 (do the forums support any bbcode for superscript?) on X and 50in/s^2 on Y. The Z settings are currently meaningless, since I'm still fighting with it. It felt like the machine could probably handle much faster rapids and the acceleration was just vaguely set based on when it felt like it was jerking too much when jogging at high speed, but I didn't spend a lot of time optimizing either one, as I figure they'll both need to be re-tuned once I've got the added weight of the big spindle swinging around on the gantry.


    edit:
    Oops... just noticed you were asking about steps per rev, and I answered in steps per inch (or "steps per unit", as Mach would have it). I think steps per rev is a fixed 200 for any steppers I've dealt with, unless you get into microsteps - at which point my settings probably won't be much use to anyone who isn't using Gecko drivers (which I believe always run at 1/10 microstepping).

    Actually, it occurs to me that my
    other numbers might not be much use to people on other drivers either, unless maybe they're also running at 1/10.


    -Bats
    (swing looooowwwww, sweet chinesespindleonthegantry.... comin' for to crash my machine...)
     
    #172 Batcrave, Jan 2, 2019
    Last edited: Jan 2, 2019
  23. Dmhaes

    Dmhaes New
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    Just double checking that the wasteboard for the LEAD is in fact 40x32?
     
  24. Rob Mitchell

    Rob Mitchell Well-Known
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    I measured my bed and the following is exactly what I have measured.
    820x1030mm
     
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  25. Dmhaes

    Dmhaes New
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    Thanks! Going to build my table and cut my wasteboard while I’m waiting on the machine to show up.
     
  26. Batcrave

    Batcrave Journeyman
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    A rotary axis was always sitting at the top of the list of additions to make to my last CNC build once I got everything working the way I wanted... unfortunately I never got things working the way I wanted, and now that I've replaced it with the Lead Machine, it doesn't have nearly as much Z headroom to do what I'd been planning.

    Considering the very first machines shipped have been in their owners' hands for less than a month, and a lot of the first batch of purchases were delayed (twice, even)... probably not. With a bit of luck, hopefully there will be some people trying it by the time you get yours.

    My first inclination was to say "no", or at least not easily - the low gantry making it tough to fit a workpiece of any significant diameter. But then I looked at your link.

    [​IMG]

    This is the one (from your link, obviously) that caught my attention... The way the Lead is built, no, it wouldn't be easy to make a single spindle travel between the two axes like this one, but doing it with a second fixed spindle does look like it should work with only very minimal changes. You could either use a longer gantry C-beam, or, like on my build, make the two 20x40s and one 20x20 (the X rails of the frame & the gantry's cable rail) shorter so that the standard C-beam extends out, then mount a second C-beam linear actuator bundle on the protruding bit to act as the alternate Z axis. Designing the rotary axis itself will take a bit more work (and likely be easier & cheaper to build separately from the main machine & just firmly mount both to the same table), but it certainly looks like a realistic enough idea.

    You'll also want to make sure both your electronics & control software can handle driving six motors (two slaved), unless you want to deal with swapping around cables and reconfiguring all your motor settings everything each time you switch modes.

    Another angle to consider is that you'll want to look at/play with some assorted design software (and, specifically, their CAM & g-code postprocessor options), since some of the simpler options may not be up to the task. Unless you need to perform 3-axis and rotary operations on the same piece, it may be easier to handle that end of things by treating it like two entirely separate machines, at which point the only question becomes "will this software support rotary axes". I know Autodesk Fusion 360 supports CAM turning now (although I've never had reason to try out those options), and is an all-around pretty impressive piece of software, with an equally impressive pricetag of $0.00 for hobbyists and startups making less than something like $100k/yr, and a not-unreasonable learning curve.

    Now I really want to do this.... maybe by the time I get the current version tuned and have time to get my mill cleaned up, reassembled, and running, maybe my bank account will have magically refilled itself enough to get the extra parts. Probably not... but maybe. Either way, thanks for pointing me in the right direction.

    Nonsense - with a project like this, you want to plan it out well in advance so that you know everything you need to order the first time around. Then you only end up placing three orders for all the parts you forgot and/or didn't realize you needed, instead of six.

    Looks like there were a couple problems with your IMG tag... first, the URL seems to have gotten mangled (with at least two http's at the beginning), and second, it looks like it was probably a URL from within a google image search, which usually don't work very well when you try linking to them from elsewhere.


    -Bats
    (why do I get the sinking feeling that I'm replying to something that doesn't actually exist? am I posting to the voices in my head again?)
     
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  27. Skip S.

    Skip S. Well-Known
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    Thanks Bats, I appreciate the info. I was trying to link things on my phone and apparently it's not forum friendly lol
    I think I'm going to go with switching from 3 axis to rotary since I don't think I'll be using rotary a lot, but I like having options in case I have an idea to make something. I'm a CNC operator by trade, so moving hookups and fiddling comes natural. I'll just keep a pad around so I can record settings and then I can keep them handy, or make a separate profile for each configuration.
    I was looking around and saw the 1010 lead machine and figured it would suit my needs, then started looking around for 4th axis options and saw the way that machine was set up, then found another that had the setup that I wanted - the X beam was longer than normal, but the axis constrained to between the supports. The leftover long side housed a Z axis and the spindle, from what I saw the spindle center and the center of the A axis was aligned, so they were essentially aligned and I knew that's what I wanted.
    If I can do that with the 1010 then I'm all over it, especially if all it'll take is an extended C Beam.
    For software I was looking at Vectric Aspire or Artcam (even though it's now defunct, it might be released free in the future etc.) I've played with Vcarve and really liked that, and due to work I've gpt Mastercam so I can fiddle with some things that way.
     
  28. Matt190

    Matt190 New
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    I was wondering if you guys can help me out, as I am completely baffled.

    I just built my Lead CNC, and have calibrated the steppers.I am using Fusion 360 with the Stroom profile and Open builds control.

    My problem is that I am getting inconsistent dimensions of cuts as well as weird travel movements
    - My first test pocket came out undersized
    First Cut Undersized

    - I then calibrated my steppers (they were off, but not off enough to cause the previous deviations)
    - After calibrating I ran two test cuts and then came out perfect.
    After Calibration Correct Dimensions

    - Then I created a new program using the same parameters (but longer) and the machine cut the pocket and it came out undersized again (same as the first cut). My calibrations were still set correctly.
    Longer Cut (same setup)

    Another weird problem - Here are photos of two programs (only a 1mm depth cut this time), They were both setup the same, but one plunged the bit right down 2.5mm on its travel to its start point, then raised up above the stock and started the downward spiral to continue the cut. Ran the program the second time and it ran normally (still not to the correct dimensions of my CAD though)
    First Time
    Second Time

    Also, as you can see, but bit looks pooched after only a few test cuts? I am using an Onsrud 1/4" double flute up-cut spiral bit. What bit and feed/speed are you guys using to cut your MDF waste board for the t slot?

    Please help!
     
  29. Batcrave

    Batcrave Journeyman
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    The immediate culprit that such inconsistent problems brings to mind is missed/skipped/dropped steps - where the program mostly executes correctly, but a couple steps here and there don't quite make it to/through a motor, which cumulatively add up to increasing inaccuracies. There are a wide variety of potential causes of missing steps, but I've most often run into them at direction changes when my rapid speed or acceleration has been set too high. The pictures, however, make it look less likely, since, unless those were cut full depth in a single pass, I wouldn't expect to see nice clean edges all the way down - the edges of some passes would end up misaligned with others.

    Another slim possibility could be a loose router/spindle mount, or a router/spindle that's loose in the mount & able to shift in one direction or another when it runs into sufficient resistance. If the mount is on loosely, it would probably manifest mostly as problems along one axis, with the other more or less accurate. If the router itself is loose, it could potentially show up in either/both/all three axes. I mention this, not because it seems especially likely, but because I did exactly that a couple days ago. Have I said "oops" lately?


    Without seeing the g-code (and, well, probably even then) I'd pretty much be guessing blindly... but is there a G28 in there, by any chance? Depending on how/when/if you've set up and homed your machine, that can cause unexpected and really ugly crashes as it tries to rapid to what it assumes (often incorrectly) is a safe starting point. With a machine that's set up properly, G28 can be a good thing, but I've spent a lot of time running without home/limit switches, so I tend to regard it as a self-destruct button.

    I don't know why that would cause different results on subsequent runs, though, unless it was re-homed somewhere else in between.

    Right now I'm using $2 Uxcell 4-flute 1/4" end mills. I wouldn't recommend using them - especially on MDF - but I can't bring myself to stick anything more expensive in the trash router I've got on there now, considering the speeds it runs at will probably just go and burn them up in no time.

    I can't give you any good numbers offhand, either, but there are a lot of feed/speed charts available online for various materials, like this one from Shopbot. Also, a lot of tool companies will publish detailed recommendations for their various tools, like this page from Onsrud, which has a dedicated chart for MDF. There's also G-Wizard Calculator (commercial, with a free 30 day trial) which I've considered buying a few times in the past, but the problem I often find (with GWiz & other sources) is that the accepted "proper" feeds and speeds for a given material aren't always possible on hobbyist machines using high speed routers as spindles - either the machine can't handle a fast enough feed, or the router can't be set to a low enough speed - so there's often a certain amount of guesswork & prematurely dull tools in the learning process.

    And yes, I've always felt like MDF dulls bits surprisingly quickly, so it wouldn't be entirely surprising to see your cut quality dropping off (and if you overheat the bit by mismatching your feed, speed, and depth of cut, you can ruin it in no time). I've read that it's supposed to be less of an issue with carbide than HSS, but I've never really tested it - I just try to avoid cutting MDF as much as possible, since, aside from shortened tool life, the thick clouds of dust are a horrendous mess to deal with (or see through) - even ignoring the potential risks of carcinogens or formaldehyde.


    -Bats
    (remember, kids - Lucky Larry Lung says "Always wear your respirators!")
     
  30. Dmhaes

    Dmhaes New
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