Nearly ruined a $3k job with MDF dust from last year

Last week in my shop in Nashville, I started sanding a built-in I was finishing and noticed the finish looked like sandpaper. Turned out I had MDF dust sitting on a shelf from 3 months ago and it got into my spray gun lines. I spent 4 hours stripping and redoing a painted cabinet door because of it. Now I vacuum out every line and cup between projects, no exceptions. Any of you guys had finish failures from cross contamination like this?

2 comments

2 Comments

cooper.taylor15d ago

MDF dust is definitely a nightmare but I gotta say 3 months on a shelf is kind of a long time for it to just magically show up in your lines. More likely it was sitting in the gun cup itself or the hose from a previous job you forgot about. MDF dust is like glitter it gets EVERYWHERE but it doesn't travel through dry lines on its own unless you left the cup open or the hose was still wet with old material. I always blow out my lines with compressed air before every single job and I keep all my cups sealed in ziploc bags between uses. That dust probably was already clinging to the inside of your fluid tip from last year.

loganm5215d ago

Kind of reminds me of the time I found a dried up chunk of bondo in my gun that I swear I cleaned out six months earlier. I was spraying some primer and it came out looking like someone sneezed in the cup. I think that dust just finds the one spot you never think to check like the threads on the cap or the little hole in the air cap. I started keeping a toothbrush in my kit just for scrubbing those threads between jobs.