MDF Help

[dangerstudios]

I am not sure if this goes here, but oh well,
So I finally got around to buying some MDF. I bought a sheet of 1/4 from Home depot and dug up a ton of 3/4 from my friend's dumpster. Well, first off, is a dust mask sufficiant protection from the dust? secondly, I know both blind squirrel props and volpin props mentioned sealing mdf to make it stronger and to hold paint better, but what should i seal it with?
Thanks

 

[exoray]

I am not sure if this goes here, but oh well,
So I finally got around to buying some MDF. I bought a sheet of 1/4 from Home depot and dug up a ton of 3/4 from my friend's dumpster. Well, first off, is a dust mask sufficiant protection from the dust? secondly, I know both blind squirrel props and volpin props mentioned sealing mdf to make it stronger and to hold paint better, but what should i seal it with?
Thanks

Wrong forum but I'm sure the staff will take care of that...

A dust mask is probably your best bet, should be sufficient for moderate use as it will clog up a respirator in no time flat...

Seal it with shellac, preferred as it's a more tolerant base coat for just about any top coat, or lacquer will work if your top coat is compatible...

Lots of people also use watered down white glue to seal it but I personally find shellac works so well I have never actually tried the glue...

 

[Invicta]

I've used thinned white glue (PVA) to seal MDF also flat latex indoor house paint (also thinned) works well and if you've got some laying around it's cheaper than buying the glue.

As for the dust mask I'd use a N-100 rated mask and change it often. Some might say a 100 is overkill but it's better than lining your lungs with dead tree.

 

[dangerstudios]

For white glue, would elmers work?

 

[GreseDraka]

It depends on what you are doing with the MDF. I am a cabinet maker and we use alot of MDF at work. When we have a raw edge on the MDF we use usually just coat the edges with a little carpenters glue mixed with some water. And then for a primer Kilz works great and could be bought at Home Depot.

 

[exoray]

For white glue, would elmers work?

That would be white (PVA) glue...

 

[Rebelscum]

It depends on what you are doing with the MDF. I am a cabinet maker and we use alot of MDF at work. When we have a raw edge on the MDF we use usually just coat the edges with a little carpenters glue mixed with some water. And then for a primer Kilz works great and could be bought at Home Depot.

what he said... it does depend on what you're doing with the edges. I never have any problem getting paint to stick to raw mdf, whether the flat from the factory finish or freshly cut edge, neither is an issue.

If you intend to put some sort of finish coat on the edges, they have to be treated with some kind of a filler that you can put primer on and sand to perfection. You can theoretically put on enough primer to eventually sand it perfect, but it's much faster to fill first.

For example, if I'm making a wooden display stand out of MDF, ie, something like a Master Replicas saber stand, I cut to fit, and smear plain drywall joint compound on with my finger. Just enough to fill the open MDF up. Drys very quick and sands smooth even faster. Then when you primer the board, the edges are as good as the uncut surface.

 

[BlindSquirrel]

I use shellac, give it smoothing sanding and then primer. Of course, as others have already stated, you'll want to wear a respirator when you sand. You don't want to breathe in any of that stuff.

 

[stormtrooperguy]

i've been sealing it with polyester resin (aka fiberglass resin). it soaks in pretty deep and makes it really solid.

 

[Anti]

I never use a mask [cough]. I'm supposed to [hack] use a mask?

Use SOME kind of mask if you don't want to be blowing dust out of your sinuses for the next 48 hours.

 

[jedimaster]

It's not the dust or dead tree you have to worry about. The glue that binds the fibres in MDF is a two part glue called Eura Formaldahide. Basically a Carcinogenic (Cancer Causing Substance). Any mask is better than none.

 

[exoray]

Use SOME kind of mask if you don't want to be blowing dust out of your sinuses for the next 48 hours.

The dust is there but the biggest concern is the formaldehyde and although it's long term effects could be debated, it's certainly an irritant that can cause lung, eye and skin irritations and issues...

 

[jedimaster]

It's not the dust or dead tree you have to worry about. The glue that binds the fibres in MDF is a two part glue called Eura Formaldahide. Basically a Carcinogenic (Cancer Causing Substance). Any mask is better than none.

 

[jedimaster]

Bugger double post. And yeah what he said.