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Post by demonic69 on Mar 16, 2015 3:58:00 GMT -5
Hi All
I have the Delta together and moving around OK, albeit noisily!
The odd thing at the minute is that the effector tilts when moved from centre, tilting away from the direction of movement (imagine a pendulum).
This happens even if I move it manually. Could it be that the length of the rods is wrong? They're 182mm at the minute and all exactly the same. Could that affect the effector angle or something else?
Cheers
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jason
Full Member
Posts: 114
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Post by jason on Mar 16, 2015 14:12:46 GMT -5
Length wrong?...well marlin needs to know..for the trigonometry to work..
My guess ...that some settings in the delta config are wrong.
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Post by demonic69 on Mar 16, 2015 14:15:26 GMT -5
Hi Jason
I did double check the settings. The thing is that it tilts even moving it manually
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jason
Full Member
Posts: 114
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Post by jason on Mar 16, 2015 15:02:48 GMT -5
Sorry if you already know this but.
To move in just "x" or"y" or "z".. your tripod has to move all three motors to achive an equivalent motion. On a conventional xyz ( cartesian ) machine..the physical axis is there and you can push the bed etc around when the motors are powered down...
In a tripod ..these axes do not exist...outside of the vitual world in side marlin..and the amount of movement on each of the three motors need to do is calculated..based on the parameters in configuration. H
And here's the point..even in jog/manual. ..so if the geometry in there is wrong then the movement will be calculated wrong and the effector will move incorrectly.
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Post by demonic69 on Mar 16, 2015 15:08:51 GMT -5
Hi Jason
I see what you're saying and it makes sense, I had it in my head that if I moved the effector by hand (turning the lead screws) it would stay level with them being on pivots but that's probably not the case. Thanks for the reply, I'll have a deeper look into the firmware, it cited be the smooth rod variable.
Cheers
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jason
Full Member
Posts: 114
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Post by jason on Mar 16, 2015 15:26:24 GMT -5
Certainly moving just one leadscrew will always swing the bed and tilt it...move all screws by the same amount. .and you get a simple Z move..All other combination will produce compound motion including tilting the effector. .its an effect of the machine geometry.. Somewhere in configuration there will be axis length rod length and both effector triangle and leadscrew triangle..all these are needed for the trigonometric calculations. .and these are to the centers ( pivots)..not always easy to measure... One might expect these to be made available to any builder of one of these kits....  |
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Post by demonic69 on Mar 16, 2015 15:30:54 GMT -5
I'll give it all another measure thanks.
You'd think the cad drawings would at least be available to take measurements from!
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jason
Full Member
Posts: 114
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Post by jason on Mar 16, 2015 16:42:43 GMT -5
yes you would.
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