Permanent marker on PLA

[sammo 0]

I've made some replacement knobs with a dial including numbering and marker lines and printed in Robot Silver PLA. They look fantastic, but I'd like to highlight the numbers and lines in black.

I've tried a Permanent Sharpie marker, a Securline II Superfrost and a Staedtler permanent laundry marker but so far none of them leave a permanent mark. They all rub off fairly easily.

Is there anything else I can use? any tips for leaving a more permanent mark? (rough up the surface with a file perhaps?)

 

[pm_dude 27]

I have a few writings in Sharpie marker and the ink seems to penetrate the layers and stay there. I have not tried to remove the writings per say so I cannot tell if its really permanent or not.

You might just need to let it dry a little more before starting to touch it.

 

[pm_dude 27]

You could also print the letters in a different color and glue them afterward

 

[tinydancer 0]

Strange, as my blue sharpie is permanent on ColorFabb PLA.

 

[sammo 0]

Cheers for the replies.

Not sure why it should be then - perhaps it's the filament? Tried a Sharpie marker first, let it dry for 24 hours and it still rubs off.

It doesn't rub off easily, but since it's on a dial that might be handled, after a while it does seem to rub off.

Printing the numbers in another colour isn't really an option based on the design and the amount of time it might take in finishing. (these are production items for sale so I want to limit the amount of labour involved in finishing the item).

I'll try some different filament and see if that makes a difference.

 

[drayson 75]

Worst case you could use the sharpie and cover the knob with a layer of transparent varnish...

Thats usual the way I protect markings on my RC planes.

[sammo 0]

Cheers drayson, I have some satin acrylic varnish, I'll give that a whirl.

 

[sammo 0]

Just to update in case anyone else has a need to do this - Sharpie marker plus satin acrylic varnish does the trick nicely.

 

[drayson 75]

:-) good to hear :-)