# New Form 4 **URL:** \ **Category:** Form 4/B/L\ **Created:** [December 18, 2025, 9:07pm UTC](https://forum.formlabs.com/t/new-form-4/45856 "2025-12-18T21:07:32Z")\ **Posts on this page:** 1\ **Showing post:** 9
**Author:** ![henryqiu](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/henryqiu/32/21840_2.png) [@henryqiu](https://forum.formlabs.com/u/henryqiu)\ **Post date:** [January 2, 2026, 1:15pm UTC](https://forum.formlabs.com/t/new-form-4/45856/9 "2026-01-02T13:15:33Z")
> [@Prinzesschen](#): > > all the resin dust has settled on the floor and the rotator and I can see totally clear IPA now again - I wonder if it would be worth it to gently pull the above IPA out with a solvent pump or so and then just throw away the last 1-2cm of the IPA on the floor, to have almost clean IPA again? Hi @Prinzesschen, welcome! I think you’ll find [this thread](https://forum.formlabs.com/t/using-cellulose-to-remove-pigment-from-ipa-it-works/45282) interesting. TLDR, “dirty IPA” refers to a combination of two things: 1. Chemical saturation. This is resin that’s been chemically dissolved and is saturating the IPA. This cannot be “filtered out” without an IPA distiller or recycler. 2. Physical debris. This is cured or semi-cured resin that floats as sediment in the IPA, and looks like dust/powder. This is what you’re seeing settling in the bottom of your wash. When I first started resin printing, I did what you described, and would occasionally run the wash through some coffee filters with a solvent pump, but quickly became too much work to sustain so I stopped. But that thread I linked above seems to be a much more automated way to solve #2 and get the physical sediment filtered out just by running the wash with some water filters inside it. If you search “filter IPA” on this forum theres a few more threads of people experimenting with recycling (or at least prolonging) IPA. --- _[View the full topic](https://forum.formlabs.com/t/new-form-4/45856)._