Maintenance notice: These forum archives are read-only, and will be removed shortly. Please visit our forums at their new location, https://www.evilmadscientist.com/forums/.

Pen 'pooling'

Arty SteArty Ste
edited August 2016 in AxiDraw
Hello,

Axidraw question if you can assist please.

I use thick pens, paint pens, markers etc for the projects I'm doing.  When the pen reaches the end of a line here is a slight delay in the pen lifting which causes a little pooling effect.  Is there a setting whereupon the pen lifts instantly or even slightly before the end of a line?  I'm finding myself physically lifting the machine to achieve this result but this obviously isn't practical in the long run.

Much appreciated.


Comments

  • Windell OskayWindell Oskay
    edited August 2016
    There is not any intentional delay there, and there is no option to lift before the move finishes. 

    If you are using the standard (Inkscape-based) software and using standard (or close to standard) settings, then what you are likely seeing is a combination of two effects. These are the slowing down of movement as it approaches the end of a path, and the physical time needed to lift the pen.

    You might try, under the Options tab, selecting the option to move at a constant speed when the pen is down. This will make it so that the movement does not slow down as it approaches the end of a line. Slowing down takes time, and can lead to pooling of ink there.  You can't go quite as fast with this mode, but it may help with the issue that you're having.

    The second effect is the physical time needed to lift the pen. You can make the servo raise faster by adjusting the Pen Raising Speed in the Timing tab. You can enter a value as high as 500 there, to make the servo move as fast as possible. However, even more important than this is that you pick an appropriate set of pen-up and pen-down positions in the Setup tab. Ideally, when you are in the pen-down position, there should be only a very small gap (1-2 mm) between the servo "horn" that performs the lifting and the metal surface that it lifts. If you have a larger gap than this, you will notice a delay as the servo motor has much further to travel before it actually starts lifting the pen.
  • Arty SteArty Ste
    Will let you know how I get on following your advice when I get chance to try them out.

    Thank you very much :-).
  • Arty SteArty Ste
    Worked great Windell, thanks so much. I think the small gap with horn and metal helped enormously.

    One more thing. Would you know why the two screws behind the pen holder keep coming loose? It's the two screws that, when tightening, the pen holder has to come off for easy access. The ones that connect the metal to plastic. thanks.
  • Windell OskayWindell Oskay
    edited August 2016
    I'm not sure which screws you are referring to. Is there any chance you mean the two screws that hold the vertical rail clamp (the silver-colored aluminum piece with the two narrow-diameter vertical shafts) to the Y Tie Block (the black-colored aluminum piece that has the two Y shafts, and a ball bearing beneath it)?
  • Arty SteArty Ste
    edited August 2016
    It's the screws behind the pen holder. Not the black screws on the actual holder, it's the silver screws that holds the holder in place. It's actually different looking than the user guide. Hope the pic below works.

    http://s1156.photobucket.com/user/Wavertree/media/5C9CE226-D302-417D-B9F6-28E9C6012664.jpg.html
  • Arty SteArty Ste
    It didn't. How do I post a pic? Cheers
  • Windell OskayWindell Oskay
    The link seems to work. And yes, those screws that you've drawn the arrows to are the same ones that I was referring to. However, there shouldn't be any plastic parts there-- that should be metal on metal on metal.

    Can you please not sure what you mean about these looking different from the user guide? I don't see any difference there from what's pictured in the guide.

    We have generally not had a problem with those screws loosening. However, if they have come loose then be sure to (1) fully remove the pen clip before trying to tighten them, and (2) use the short side of the 3/32 hex L-wrench to tighten them. If they persist in loosening, you might try a drop of threadlocker if you have access to it, or adding a small dot of glue to the side of the screw head (once attached) to prevent it from turning. You might also try tightening the two screws one at a time (tightening only one of them -- leaving the other loose) to see if perhaps one of the screws isn't really tightening at all.
  • Arty SteArty Ste
    Sorry yes it is the same as the user guide - been a long week :-).

    Yes I removed the pen clip last time but probably didn't tighten them enough.

    All good tips there Windell, will try if and when they loosen again.

    I see you have an optimisation tips page on wiki, might be worth adding a general tips page which summarises things on the forum.

    Thanks again and good luck with the machine.
Sign In or Register to comment.