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#91
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I would go back and check all wiring connections on the machine, then check again before tweaking anything else. Everything looks like it is in the right ball park. Had similar issues where it it was just lose stepper wiring, mainly where i had more than one wire on the same connection.
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#92
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Did you get this sorted?
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#93
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Hi Paul, yes and no, I got it mostly sorted. The remaining 20% not sorted will just take experience to solve. Feeds and Speeds.
1. The .9 (I failed maths) error was caused by using a metric offset with an imperial tool and just bad maths. There seems to be a lot of simple maths in my new hobby. Thanks Peter. 2. The hypotenuse concave was caused by tool deflection, I have reduced my feed rate and it goes away. I'm still playing around with feeds and speeds. (more maths) I've taken to keeping a job diary. I basically sketch down every job I chuck on and write myself some speeds and feeds notes and other setup info like jigs and tools and preparations, post finishing. This part of learning to run the machine will never end I suspect. I have found a new fault introduced recently thats really interesting. One of my drivers spits out spurious steps for no reason. I was out in the garden and heard all this grinding noise coming from the garage and got a shock when I walked in and found the machine crabbing up the X axis. The computer was off, BOB off, and just the main board had power and K1 (Main) contactor was on so there was DC power. I did some simple swaps of drivers and motors and found that whatever motor was connected to the suspect driver was getting steps driven. During my fault finding I changed my micro stepping dip switches to 10 micro steps and the fault went away. Then I changed back to 256 micro steps and the fault still stayed away. The fault has since come back twice. Never while running a job but when the DC is on idle for more than an hour or so. All I do is flick the dip switch at random and then set them back to 256 steps and all comes good. MotionKing are sending me a new driver. So it's a pain, but, it's not stopping me. By the way, some of you probably read the Christmas Bauble's discussion. That project was both a huge success and a big ass failure. Success, the baubles design actually turned out nice. I learned a LOT! Feeds, Speeds, WCS, G28, G54, CAM, File management, Design to CAM process, tool changing... It was lots of fun. Failure, the entire sheet of baubles ended up ruined because very early in the 'Side B' of the job the tool picked up the paper I put down on the material for paint masking in a later process. The paper wrapped up in the spindle and broke a 1.2mm tool. I replaced the tool but didn't home or check my work position. The fault must have caused some lost steps and the job ended up with Side 'B' misaligned to Side A. Lesson Learned: Design simply. The job was just too complex. If I do it again I will reduce the variety of designs in the baubles and maybe just use now row of unique designs and use offsetting to duplicate each row down the sheet. I would also put more thought into the tool I intend to use to produce the design at the CAD stage and try and get better balance between positive and negative space in the designs, i.e. use patterns that aren't biased toward all milling or all unmilled. The thing I was most happy with about the job is my Z axis verticality. My pockets show virtually no tool pass marks at all. And my circle have hardly any chatter which is great, especially without running reduction gearing. |
#94
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256 micro steps? Why would you want that many for? It reduces the actual torque and doesn't improve real resolution. 8~10 is where the sweet spot is.
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#95
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Dale, I would expect any driver with floating inputs ( BOB and computer off ) to behave unpredictably. The wires and unpowered circuits act as antennas and can pick up and amplify electrical noise.
I would not expect a driver with disconnected inputs to do this, but as soon as you attach a wire and don't have the source on, you're in random territory. Standard practice on systems that amplify small signals into large ones is to turn them on from source to output, and turn them off from output to source. That way you're never leaving inputs open to noise, whether it be a concert audio system, a radio transmitter, or a CNC machine. |
#96
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Do you have the 'Enable' connected on the drivers? if not i would add them in. it will take another pin from the bob but still gives extra saftey here.
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#97
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@Paul, I don't have the enable connected but its on my list of things to do, As well as taking out the alarm signals back to the BOB.
@Brad, whatever the issue is with the driver it is only the one driver that does it and in testing the driver is failing even without signal wiring connected. The driver uses plug in terminals, so I did a bit of swapping when I was trying to isolate the source of the fault. @Ken, I'm really interested in understanding more about torque sweet spots in the motor/driver combo. My drivers let me use microsteps from 10 to 512. I started with 256 because it was in the middle and haven't had any problems with torque or losing steps so just left it. |
#98
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From www.geckodrive.com/support/step-motor-basics.html
Quote:
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#99
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A year and a bit later
Hi guys, I haven't posted in ages but do check in and snoop from time to time.
I thought it might be helpful for others to run through a bit of a lessons learned and follow-up to my MechMate. First. The machine is going really well and only gets better and better as I further develop the machine and my skills. In particular my experience and skills as a machinist and designer are the most important aspect of this machine. For those considering building a MechMate do not underestimate what comes after. Operating the machine and designing for the machine are considerably more challenging than bolting together and welding steel and wiring up stepper motors and drivers. At least that has been my experience. I have added a Z axis home limit. It's probably not necessary but in the early days I kept ruining jobs due to my poor understanding of G28 and that resulted in the tool taking of and gouging through material due to inconsistent Z (machine coordinates) position when initially turned on the machine in the morning. Adding the Z axis home limit meant that I was able to ensure consistent machine coordinates for Z as well as X and Y. I have added a Z zero plate. Setting with Z zero with a paper became very old very quickly. I dumped my MotionKing 2LD545 stepper drivers and replaced them with Leadshine EM806 stepper drivers. One of my MotionKing drivers developed this weird thing where it would intermittently and at random change microstepping units. I had all my stepper drivers set up for 10 microsteps and during a job from time to time the driver would just start outputting a different microstep value. It started on one of my long axis drives so I noticed immediately because the in the middle of the job the gantry started making this loud grinding noise because the left drive was moving at 10 microsteps increments and the right motor was moving at some other increment despite them both being fed the same step signals. I would turn the machine off and on again and the fault would go away, to not show itself for 6 weeks or more at times. Then it cam back again. The fault took me ages to track down. At first I thought maybe the BOB was outputting weird steps, but my oscilloscope proved that wrong. Eventually the problem became so regular that I was able to prove it was a specific driver by swapping the drivers around and watching the problem move to the new axis. I spoke to Motion King about it but they weren't interested in helping me except to sell me a new drive. In the end I decided to buy 4 Leadshine drives instead of one new replacement MotionKing drives because the really aren't all that expensive and I just felt grumpy towards MotionKing. Not really a good reason, but, anyway. The new Leadshine drives meant I could add missed step detection alarms/stops. So I did. It's reassuring to know it's there, but, I don't think it ever operates these days. Would have been much more handy in my early learning days when I was struggling with too deep cuts and poor cutting strategies. I buy really cheap tools from China off eBay. They don't really last as long as good tools but on a cost to operating hours basis 10 cheap tools still beats a single good tool every time. Good tools just aren't worth the price premium in my opinion. I had a strange comms problem with my ESS. It was just losing comms in the middle of a job. Was really annoying. I eventually isolated vibration on my Ethernet card as the problem. Because I use a touchscreen all-in-one pc mounted to the front of my machine I couldn't replace the Ethernet card so I just installed a USB Ethernet dongle and it works great, no more problems there. I settled, finally, and after much soul searching and demoing on Fusion360 for my CAD/CAM environment. I don't pay for it I have a hobby licence. I'm not earning any money with the machine just exploring art/craft and personal projects so there's no conflict there. I really love Fusion360 it helps me express my inner designer. I can't recommend it enough. I love to model up new projects and then create really high quality renders and the move into the CAM environment and set my work-paths. It's a great one stop shop. Fusion360 has matured enormously over the past two years. I participate in the Autodesk Fusion 360 forums a little bit and they (Autodesk) really listen to the designer feedback. They are about to introduce sheetmetal tools that will allow developing complex 3 dimensional planes to flat planes. This is going to be a really important addition to my design quiver because it will let me consider designs that use plywood in twisted and bowed shapes but cut from flat sheets. I have some boat designs I want to work on when that comes in. I never got around to putting on stickers. It's still on my todo list. I really want to add vacuum hold downs. I have been using these cheap plastic spring clamps to hold sheets to the baseboard. Occasionally I'll drive a tool straight through them. Doesn't seem to bother the tool and I just chuck the broken spring clamps. But vacuum hold down will definitely be a big improvement in my workflow. I added dust collection but haven't made a decent dust shoe that works effectively. Most of the time I run without dust collection. It makes horrible mess but my garage is semi enclosed, more of a carport really, and I just use a petrol garden blower to blow the sawdust out into the garden. I have discovered one advantage of not using dust collection. I tend to design cut profiles without using tabs. The sawdust fills in the cut path and holds the internal part reasonably still during the profile cut through. This means I don't need to worry about tabs and my internal part moving. It really isn't an ideal work practice though and when I do eventually get vacuum hold down going I will really need to revisit my dust collection shoe design. I use a lot of Hoop Pine ply. Russian Birch ply is really nice and Hoop pine ply is just as nice but slightly cheaper. It should be cheaper than it is I think. My ply costs are frustrating but I have learned that it's better to spend a bit more on nice ply than to spend forever sanding and prepping for finishing crappy ply. Oh, one final thing, accelerations and speeds, along with feeds and speeds are an on-going and never ending tuning and learning curve. I cannot recommend enough that anyone considering building a MechMate commit themselves to research, practice and experience building knowledge in this area. Well, that's about it, happy to answer any questions. Dale |
#100
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I have found that the saw dust does help with keeping piece from moving but they also help with dulling the bits quicker.
I never heard of Hoop Pine but I see it is grown every where. |
#101
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Thank you Dale, nice feedback.
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#102
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Dale,
You have provided a really nice summary/article about your experience with the MechMate.. I very much appreciate your taking the time to provide us the information about your experiences and give us the benefit of your learning. I must admit, I'd like to see photos of some of your work, but still the article is well worth the read. Finally, I would like to encourage you to add the stickers and qualify for a Serial Number. You certainly have earned it. Regards, John Higgins |
#103
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This photo is a project I'm working on right now. It's a stand up paddle board. I designed the paddle board in Fusion 360 from scratch, as a t-spline object, and then developed the stringer and frame shapes as models that I then placed into a nested arrangement for developing the CAM work paths. The paddle board will be made using strip planking hollow core construction, very similar to many strip planked canoes and kayaks. It will be completely sealed, with a breather, and fibreglass sheathed. Strips will be from Hoop Pine solid lumber cut into strips on my bandsaw. There will probably be some decorative contrasting timber elements but I haven't planned that yet. This is a screen shot of the model and the CAM nesting layout. All pretty much self explanatory. https://goo.gl/photos/GJuLtWWKTBPJNTC48 This link will take you to a series of renders of the finished product. The renders arent that good I need to spend some time on the texture map controls to get everything looking spiffy. |
#104
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This is a video I made of a video booth prototype I made for a mate who is thinking about making video booths for events like weddings. Anyway this was all very rough and ready just to get the concept across the line. I'm not sure whether my mate is going to go ahead with more of these or what. But it was a fun project.
https://goo.gl/photos/c5ZLE36ykn78FfFk7 |
#105
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This links to a few screen shots of a project I have going in the background, not even near cutting yet. It's the Iain Oughtred Yawl Roan Mor. A 25' double ended yawl.
https://goo.gl/photos/cRBBctxXb4Gg4KfV6 This is the project that I'm really waiting for Fusion360 to release the sheet metal tools so that I can develop the planking for cutting from the model. There's other ways to develop the planking shapes of course but I have so many other things going on this little project is just sitting on the back-burner. |
#106
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Cutting out the stringers for a Paulk workbench I made for myself. I love my Paulk work bench but I didn't follow Paulk's instructions and because I knew better made it from solid timber and increased the specs of the space frame construction. Paulk recommends 1/2" ply and I used 3/4" ply for top and bottom and 3/4" pine for stringers. The result is my bench is really heavy and not really portable which is kinda the point. On the plus side it's solid and beautiful to work on. https://goo.gl/photos/Xdwti7CQCvzADdXw8 https://goo.gl/photos/FqR2Qoqyqq9ZFwzMA Link to photos of Paulk workbench parts being cut on MechMate. In the second link you can see how I modified the Paulk workbench design to add a bench vice. Last edited by Duds; Sat 11 June 2016 at 22:54.. |
#107
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A little clock I made for the kitchen at home. This was a just a mucking around with exploring engraving letters project. |
#108
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A bunch of tables and chairs, I made for a mate that was opening a cafe. He's been a Barista for years but this was his first cafe as an owner. The brief was "Make it tough, make it CHEAP!!!!" The tables were made from old doors and the chairs from form ply. I charged the stools out at $20 a pop, I made nothing on them just covered materials. But I have a special place for these stools. I really like how they turned out. I've often though of making some more for myself but in some really nice ply. Last edited by Duds; Sat 11 June 2016 at 23:22.. |
#109
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A prototype stool I made for my Barista mate. I made this for nothing and gave it to him. Didn't finish it at all it was a really quick little job. My mate loved it but just couldn't afford to buy any. I couldn't produce them for $20 a pop.
![]() https://goo.gl/photos/TWLZsvRJVQvPR7cR9 |
#110
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I made the distribution board cabling shroud with the labelling and the sign. I also made the pine stools. The stools were also a prototype. I never sold any of those stools. They are a beautiful shape and I loved the negative space and the way they stack but they were just way too weak. It was trying to pare the stools back to the minimal nothing and went too far. Beautiful to look at just don't sit on it. |
#111
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A bracelet I made for my wife. |
#112
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Wow, ultra impressive work Dale. Looks like you are getting a great grasp on things!
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#113
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Dale, very impressive work. Thanks so much for sharing. You have, clearly, achieved a high level of competence with both the Mechmate tool and the software to drive it.
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#114
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Dale, was looking at your F360 screenshot and see a Position set in the toolbar. Where did you get that from? Been searching my install (also on Mac) and can find that toolbar item anywhere or any particular add-in that would create that. Any info on where to find that elusive item would be appreciated...
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#115
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Thats the position capture and release buttons. I don't use them. They seem to be only available after you have created a t-spline form. You might have noticed that moving bodies, when you have duplicates, does some weird stuff. ie if you move body A(1) then body A(2) will also move. But if they have different orientations for their origins they will appear to move in unfathomable ways. In actual fact they are both A(2) is moving the same X,Y and Z parameters as A(1) but because the orientations of their origins are different the global X,Y,Z parameters moved are different.
Selecting an object from the object tree will select only that and move it. Selecting an object from the workspace will select that object and infer selection of it's duplicates and will move the duplicates as well. Capture will lock in an objects new position as it's orientation and origin. Release will maintain its prior position and orientation and origin as the current orientation and origin. Any actions applied to a released object will apply in reference to the prior (original) orientation and reference. I hope that makes sense. |
#116
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Aha, thanks Dale. I suspect I have never noticed it before while using Fusion, have moved a heap of things but haven't scanned the toolbar during it.
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#117
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@bruce, I just realised I told you porky pies, partly. The position tool set shows up whenever you move a duplicate object, not related to t-spline objects. The tools let you lock in the current position or revert to original position. The rest of the stuff, about origins and orientations still remains true.
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#118
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Just beginning
Gudday Dale
I am about to start building a Mechmate and whilst I have some Mech Eng background it is neither as relevant nor as recent as yours. I am retired, live on a small farm in the middle of nowhere and I want the Mechmate for purely recreational usage. There is no chance it will be used commercially, I left all that behind when I retired. I find the prospect of the build a little daunting but I am hoping that the Mechmate Forum will help with support and advice on the more difficult issues. That said, I am not without assets: Mike (Metalhead) has given me a lead to rnixon in Melbourne for a laser cut kit. I have very well-equipped engineering and woodworking workshops, I have a tame electrical/electronic genius available to me for the final build and I am not in a great hurry. I would benefit from some advice on where to buy Mechmate components in Oz. I live about two hours out of Canberra and I would appreciate an opportunity to meet up and discuss your experience and of course, to listen to any advice you choose to pass on. I am also very interested to see what additional features you have added to your machine. If you can find the time to talk with me, please advise a convenient date, time and location. Regards truckers10 |
#119
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Hey Truckers,
Give me a call sometime on 0400 944 492 and we'll figure something out. Happy for you to come have a look at the machine sometime. I haven't been using it lately too busy with other work. It's a good machine, the mechmate, solid and reliable. My biggest recommendation will be to learn CAD/CAM. The results you get out of it are directly related to your design skills. Start researching feeds and speeds, start researching tools and tooling, start researching CAD, and get an understanding of g-code and offsets. I look forward to your call. Dale |
#120
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Gudday Dale
This is my second attempt, something odd happened with the first and I'm not sure it was submitted. Thanks for your time and help with in our discussion on Saturday, I now have a clearer picture of the project ahead. You mentioned several suppliers of components, could you please give me some leads on them, in particular: Canberra steel merchant; Rack, pinion and v-plate (Queensland?) Spring Gas strut (Melbourne?) Router head (Internet?) Many thanks Paul Scammell (02) 4847 1201 truckers10@activ8.net.au |
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Thread | Thread Starter | Forum | Replies | Last Post |
Mechmate for sale in Australia | MattyZee | The Market Place | 3 | Wed 06 July 2011 18:44 |
Started on the electrical box - Canberra, AU | garymo | Construction started, but not cutting yet | 29 | Mon 30 May 2011 08:25 |
Hi from Canberra Australia | Listek | Introduce yourself and start planning | 1 | Mon 07 February 2011 01:12 |
MechMate Laser cut Kits in Australia | MetalHead | The Market Place | 1 | Wed 06 October 2010 15:11 |
Hi from Troy ,VIC ,AUSTRALIA i plan on building a MechMate | conceptz | Introduce yourself and start planning | 20 | Mon 07 September 2009 01:33 |