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scales82
2nd May 2016, 02:15 PM
Hi all. Going to prime my mdf ready for the next build. This cab will mostly have vinyl art applied so was wondering if anyone had recommendations on what to use? Anything non vinyl will eventually be painted white.

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FLEX
2nd May 2016, 04:20 PM
Just use a white water based primer from bunnings.
Sand it with 120 grit, Paint it, give it a very lite sand with 120 grit again, then give it a second coat.
Make sure to give it a final very lite sand with 120 or higher wherever you intend on applying the artwork. This will ensure there is no little sharp lumps or droplets that may cause havoc under your artwork when you apply it.

scales82
2nd May 2016, 04:38 PM
Thanks. Brush or roller? I am not a great painter

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jason1
2nd May 2016, 04:57 PM
Typically I would give the MDF a sand with some 600 grit to remove the shine only for the primer to bond too, and then etch prime then use a 1k primer. sanding it with rough paper will give it sand marks which you dont want. and use an etch and then a 1k primer, etch primer will allow the 1k primer to stick
I would spray the primer as using a brush or a roller will give it a crap surface under the vinyl and it will print through the vinyl and you will see the brush marks

each to their own but thats what i do

Lazarus
2nd May 2016, 05:08 PM
If you aren't confident or don't want to spray - you can apply an automotive primer with a smooth roller - AS LONG AS you sand smooth once it has cured. This is a good solution for 2 pack primers (if you don't want to be spraying that stuff).

Topcoat - i'd be spraying the colour, and typically use an automotive acrylic. You can get colours mixed up into aerosol cans and you can spray it legally at home.

scales82
2nd May 2016, 06:29 PM
Well I am confident spraying. I have a 450lpm compressor I can use at home. My brush work is garbage that's all.
I just want to paint all the pieces before fitting together. Its a wwf flat pack bar top that I've been staring at for months. And I just moved house so time to get to work

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Lazarus
2nd May 2016, 06:48 PM
Lay your pieces flat and spray some acrylic primer. Let dry, sand and spray acrylic topcoat. Let dry, apply decals.

scales82
2nd May 2016, 06:56 PM
Sounds like a plan. Just need to wait for the wind to calm down. And buy a new spray gun lol

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jason1
2nd May 2016, 06:57 PM
dont forget an etch primer,

scales82
2nd May 2016, 06:58 PM
Is that available from bunnings?

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Lazarus
2nd May 2016, 06:59 PM
dont forget etch primer, you dont want the paint too fall off
Etch primer is for bare metal. You don't need this.

jason1
2nd May 2016, 07:00 PM
no its good for MDF as well

scales82
2nd May 2016, 07:00 PM
Hmmm

Lazarus
2nd May 2016, 07:00 PM
no its good for MDF
No.

jason1
2nd May 2016, 07:01 PM
No.

each to their own, I guess

Lazarus
2nd May 2016, 07:06 PM
each to their own, I guess
Again, no.
No need to guess, etch primer is not required for mdf.

Etch primer uses an acid to etch a metal and facilitate proper bond.
MDF is already porous and regular primer has no issue bonding to mdf.

scales82
2nd May 2016, 07:06 PM
I tend to agree.

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OzStick
3rd May 2016, 10:32 PM
Why are you unable to adhere the vinyl directly to the "raw" MDF?

I used to make a lot of desktop joystick units out of MDF and used a self adhesive vinyl overlay, but never did I paint or seal the panels first.

If you are concerned about the vinyl possibly coming adrift in the future, then maybe try a 50/50 mixture of PVA and water and give the MDF a light coat with a roller. Once dry (which won't take long), sand with a fine sandpaper, give it a second coat and lightly sand again. You should then have a smooth, almost impervious surface on which to lay on your vinyl.

It may be a low tech solution, but it most certainly works.

Roxbury
4th May 2016, 07:07 AM
I have applied vinyl overlay to mdf and old chipboard that had not bloated or been damaged without using paint/ primer.

3 LAI cocktails done almost 5 years ago and no signs of issues with the vinyl. Looks like it could have been applied yesterday. Note that LAI cocktails made with chipboard had vinyl applied directly to the bare chipboard with adhesive when they were originally made.

scales82
16th May 2016, 02:18 PM
I just want it to last longer and seal against the elements really. Ill take the raw option into consideration though...

While we're on the topic. Anyone suggest a reasonable place to get some bartop vinyls printed up in Melbourne? I just moved down from FNQ.

OzStick
18th May 2016, 01:00 PM
I just want it to last longer and seal against the elements really. Ill take the raw option into consideration though...

While we're on the topic. Anyone suggest a reasonable place to get some bartop vinyls printed up in Melbourne? I just moved down from FNQ.

Try Ink On Paper in Clayton: www.inkonpaper.net.au