POST PROCESSING


What you'll make:
A smooth, glossy finished cover ready to wear, taking your print from raw plastic to a polished final surface using sanding and XTC-3D resin coating.

What you'll need:
Your printed cover
Sandpaper: 120, 220, 400, and 800 grit
XTC-3D brush-on coating (available on Amazon or most maker supply shops)
A small disposable brush
Gloves and a well-ventilated space


SANDING



Step 1: Start Rough (200–400 grit) Get rid of major layer lines. Keep the surface wet to avoid clogging the paper and to reduce heat friction on the plastic. 

(ALWAYS SAND IN CIRCULAR MOTIONS)
Step 2: Medium Smoothing (600–800 grit) Eliminate the sanding scratches left from Step 1. The surface should start feeling noticeably smoother under your fingers. Keep it wet throughout.
Step 3: Fine Finishing (1200–2000 grit) At this stage you are refining, not removing material. Work slowly and evenly across the whole surface. By 2000 grit the cover should feel almost smooth to the touch. 
Credit: 3d Sourced  


RESIN FINISH 


Tip:
Wipe the cover down with a dry cloth to remove all dust and moisture before moving on — any residue will affect how the resin bonds.



    Step 1: Mix the Resin Mix XTC-3D Part A and Part B in a 2:1 ratio by volume. Stir for at least two minutes; undermixing will leave soft or tacky patches after curing.

    *Optional Primer Apply a light coat of spray primer and let it dry fully. This helps reveal any remaining imperfections and gives the resin a better surface to bond to.  
    Step 2: Apply the First Coat Using your disposable brush, apply a thin even coat over the entire surface. Work quickly as the resin begins to self-level within a few minutes. Thin coats are always better than thick ones — one heavy coat will drip and pool.
    Step 3: Cure Leave to cure for at least 4 hours before touching and 24 hours before handling fully. Keep it in a warm room — XTC-3D cures faster and more evenly above 20°C.
    Step 4: Optional Second Coat Once fully cured, lightly sand with 1500–2000 grit again to knock back any unevenness, then apply a second coat following Steps 5 and 6. This will give you a noticeably glossier and more durable finish 

    EXTRA TIPS: 
    If you want color, paint before applying XTC-3D so the resin seals and protects the paint underneath

    Wear gloves! The resin is sticky and skin-irritating before it cures

    Work in a well-ventilated space, the fumes during mixing are strong.

    Credit: Matterhackers


    designed by pao (paogutierreznavarro.com)