PDA

View Full Version : Painting MDF creations cut on CNC or laser?



rissole
3rd February 2016, 05:51 PM
Hello
I cut various MDF items on my laser machine that up until now I have simply painted with tins of spray paint. There must be a better way to do this, Im assuming with a spray gun of sorts. I haven't had much luck googling and these are the sorts of things I want to know -

What types of paint to use, ie can I just use normal water based acrylics from bunnings, I read somewhere about using auto paints? Ive seen people painting similar items that I make using metallic paints? This looks great and wondering what or where this type of paint is from?

What type of gun, I use lots of different colours, so can I get a gun with several smaller pots that I can keep filled with the paint until I use it again.

Where in Brisbane I could go to find these items?

Id appreciate any type of information as I just dont know where to look. Thanks so much:(

Master Splinter
3rd February 2016, 08:13 PM
Air compressor - anywhere from $200 to $1,200 depending on your expected volume of spraying.
Spray gun - the Workquip set - https://www.vektools.com.au/workquip-gravity-spray-gun-with-stand-3-tip-setups.html is a good starting point.
If you think the Workquip set is beneath your tool purchasing dignity standards and the low price offends you because you must have top quality tools, then be prepared to part with anywhere between $200 to $1,200 PER TIP SIZE for trade quality guns.
Different tip sizes are needed for the various types of paint - roughly 1.2 for 2pac, 1.8 for automotive acrylics, 2+ for spray putties.
Gravity feed guns are 'the in thing' these days.
Changing colour is a process of tipping the paint out, cleaning the gun, and refilling the pot with a new colour; or having two or more guns. Trade spray painters will often have a putty gun, an undercoat gun, a topcoat gun or two or three, a clear gun, and possibly even an even better clear gun for really smooth finishes.
You can tell that a gun is 'professional' if the cost of changing the tip, air cap and needle is pretty much the same as buying an extra gun rather than an extra $20.
Supercheap Auto has a range of automotive acrylics that also work well on wood, especially MDF. See also primer surfacers and spray putty.
Custom mix colours are also available from Supercheap, including all the metallic colours you find on cars.
Even more types can be found at dedicated automotive spray paint shops. They can also sell you quick dry enamels at nice prices.

I've found that standard water based acrylic paints (house paints) are a good way to encounter endless frustration and gummed up spray guns.

As for how to spray -
https://www.youtube.com/channel/UCzJ7rCZtG8GVVKjv8_eynUg
https://www.youtube.com/user/customspraymods

Both those sites are good, but the Gunman is generally demonstrating 2 pac isocyanate paint, which needs either an air-fed mask, or a good mask like a Sundstrom with a fresh A2 filter and a strict "I stop using this filter eight hours after opening it, no exceptions, even though the filter costs $30" policy. (you can't tell when a filter is letting isocyanates through....or if you can, it's already past the safe exposure limit and you've been breathing them in for a good while before you noticed the smell).

rissole
3rd February 2016, 08:38 PM
Thank you so much for your reply, I really appreciate it :)
Larissa

pictureman
12th February 2016, 01:37 PM
spray paint the MDF with automotive undercoat, sand to clean any imperfections. top coat with a nitro finish or auto finish and to help with a fast drying finish use a clear that is about 30% gloss as this will help to keep the wax from coming to the surface, the finish will be smooth as.