Is it possible to print 25um sized channels?


#1

Hello all,

I’m working on a microfluidics chip and have noticed a couple others on these forums doing the same. However, others seem to be working on a slightly larger scale than I am, and I’m curious if it would be possible to print a microfluidic “channel” with an interior circumference of 25 microns ( or .025 millimeters) embedded completely inside the chip.

The reason for this is because cells tend to be about 10 microns in size, and so I would need the channel to be 25 microns or less in order to restrict movement to a single cell only.

The goal would be for the channel to not be clogged or collapsed of course - I have the form 2 currently but would be curious to try out a form 3 if this is possible on the new machine.

Thanks all,
Ebg


#2

My models usually have tiny holes. The smallest I could get that would definitively print was 0.4mm. In the model I make it 0.5mm to 0.6mm (STL file), it prints at 0.4mm or just a bit less than that. If I have a hole in model that is less then 0.5mm then it won’t print in standard gray resin (it closes up). I don’t see any way you could print 25um holes or channels (at least with F2).


#3

Thanks Boris_Krzic, I appreciate the input. I also felt 25um might be too small of a scale to be possible at the moment - though I also keep hearing that the Form 3 has greatly improved resolution and laser point size. Maybe I will try getting in touch with a formlabs representative to see what their insights on this are.

Has anybody else with the Form 3 found success with extremely small scale prints? I will report back here if anyone from formlabs can give me any insights about the small scale print capacities for the new Form 3 too.


#4

For extremely small scale prints, maybe a DLP printer would be a better option, as with these printers you can often enhance resolution at the cost of build volume (by using the “zoom” of the DLP projector). With SLA you’ll always be constrained by the laser spot size. On the other hand, for tiny holes a “pure” SLA printer like the form 2 may be the best, as it can create holes by just using the galvos for doing the “circle” around it (IDK if it actually does it that way).


#5

It’s always worth asking our sales team if they could do a custom sample part for you here in the office! No guarantees, but they’re often willing to do that to make sure the printer will do what someone needs before they buy.


#6

25 microns won’t work, the laser light bounces around within the resin a bit around where the spot hits. In cases where the resin isn’t moving around much (like in a hole) the indirect curing can cure the resin over repeated exposure when doing the surrounding surfaces.