MDF vs Ply vs MDO? Thickness?

[jcroach]

Ok, I'm starting to build a cabinet.

[CJK]

If your cabinet sides are structural (most are), you'll probably want 5/8" or 3/4" panels. The CP can be made out of something thinner, since it doesn't bear a lot of weight. You might have to rout out a recess for the joysticks no matter what thickness of wood you use, because some joysticks are designed to be mounted in a metal CP. The best bet is to mount one in a scrap piece and see if you like how far the stick protrudes from the panel. It might be too short, in which case you can decide whether to mount it in a recess on the top or bottom of the panel.

You pretty much covered the plywood vs. MDF debate. 

MDO is great stuff -- it has the advantages of plywood (holds fasteners better) while giving you the great paintability of MDF. It's pretty easy to work with, but like regular plywood, doesn't take an edge well. (I.e., routing the edge is not going to give you particularly nice results.)

Properly prepared MDF or MDO gives you the best painted finish with the least amount of agony. You'll go through a lot of sandpaper and paint trying to achieve the same finish with regular plywood. If you do decide to use plywood, get one with a sanded finish on one side (birch is the most common) to save time and effort.

T-molding slots are easy to make in MDF with a router and slot-cutting bit. Harder in plywood because of tearout, as you mention.

Regards,
-- Chris

[jcroach]

Thanks for the advice, MonitorGuru and CJK.

I've seen the Melamine at Menards before.  What's on the interior of these?  Is it more like particle board or MDF? Is it sturdy?

[CJK]

It's usually particle board, but I've seen some that had MDF in the middle. Yes, it's sturdy either way.

-- Chris

[joshbr7257]

what about 1/2 wood for the cabinet sides ( im not sure what type of wood it is) but i found a couple huge sheets in my garage and i thought id save money by using that but is 1/2 to thin, im not planing on t-molding it.

[RTSDaddy2]

You'll definitely want to use 3/4" on the sides, if plywood. Don't be cheap on those sections of your cabinet as they are "main" pieces (in my honest opinion).

RTSDaddy2

[joshbr7257]

what if i braceit with 2x4s on the insides though, this is my first project and i was thinking i could make this using as less money as possible to be kind of like a concept version and in the future then i could make a cabinet really good cabinet after getting the expierience, but if everyone agrees not to use 1/2 then i wont, what do you think?

[DrewKaree]

I think you've got to read this thread several times, because enough folks have posted good solid answers you aren't listening to.  YKour first question was answered less than a handful of posts above it.  I'd say if you want to do it, and you state that you're going to build a newer/better one after this first one, then DO IT - the brace idea - and then you TELL US how your project came out.  Seems to be the only way to learn if it'll work, and your experience will help the rest of us.

Thanks Chad 

[Zakk]

I'm with Drew on this, I think you want to hear someone say that it's okay to use 1/2" because you have some lying around, but really, you will regret it later, just go get some 3/4" sheets and be done with it.  1/2" is just too thin to be structutally sound.  However, it is your project.

Even though you don't think your want t-molding now, you may in the future to give it that finished look. 

[Nannuu]

You can use 1/2", especially if you use 2x4s on the inside.  But you'll have to drill from the outside, then putty and fill all of those holes.  My first cabinet was 1/2", it's 18 years old and is still as solid as ever.

It's better to use 3/4", it looks better and you will most likely want to use t-mold later.  MDF is only about $20 a sheet.  Really cheap considering what you are making.

[daywane]

on a budget are we?
join the club, Don't want to spring for 3/4 inch.  Cant say I blame you. $50.00 a sheet here in KY.
Think about finding a old empty arcade cab. You say it's to get your feet wet (so to speak, not your words but same meaning)
Look around, you can find them for free to $25.00 all day long . Bolt in some 2x4s
place a board on the 2x4s as a shelf and wedge in a 19 inch monitor.
I have bought 3 of ebay in the last few months. All under $50.00
(  :police:stay away from the one in Louisville KY on ebay now that bad boy has my name all over it  ) No shipping local pick up.
do a search on ebay for 19" monitor , 100 miles from your zip code

[joshbr7257]

thanks for all of your comments, i think im just going to try this out with the 1/2in wood and ill brace it with 2x4s (cause i gota ton of those lying around too) ill let you guys know how it turns out, i think ill take some pics as its being made to

[danny_galaga]

d) if you want a white cabinet, go with Menards Melamine panels. NO PAINTING needed.. hard white plastic finish. They're 3/4" and $22.99 on sale (used to be $19.99 last year).

[DrewKaree]

if you look around, you can find black melamine too. thats what i might use for the upright i eventually want to make (unless i paint it purple)

You want it to match the room your cocktail was in?

[jcroach]

Slightly off topic, is it trrue that you should only use oil based paint on MDF?  I've seen that mentioned on the boards before.  I know that water and MDF don't mix well, bu I wouldn't think that would apply to paint.  Or does oil based paint just give a better finish?

[CJK]

Yes, it's true: If you use a water-based paint on MDF, you'll be sorry. 

That said, you can use it if you seal the MDF first with an oil-based primer. Make sure the paint you end up using is compatible with the primer, though.

-- Chris

[jelwell]

Does anyone sell custom sized metal control panels? How hard is this to make at home?
Joseph Elwell.

[danny_galaga]

Yes, it's true: If you use a water-based paint on MDF, you'll be sorry.

[armax]

I was wondering where everyone got the notion that water-based primers and paints act the same as water when it concerns damage to mdf...

it won't swell,warp or damage the mdf in any way.  old wives' tale...

[CJK]

Water-based primers and paints will cause MDF to swell; the amount of swelling depends on the amount of water absorbed. (And yes, water-based products behave like water because they contain ... WATER!) If you brush on the paint, you will get more swelling than if you spray, for instance. The effect may not be noticeable in your particular application, though, so a reasonable idea would be to test a scrap piece with the desired paint/finish. Also, some grades of MDF (yes, there are different grades) will be more absorbent than others.

If you want to paint your MDF cabinet with water-based latex, go right ahead. Just realize that you'll be spending some extra time sanding between coats to get the same finish you'd get if you used a solvent-based system instead.

-- Chris

[Dire Radiant]

Does anyone sell custom sized metal control panels? How hard is this to make at home?
Joseph Elwell.

I wish... I've been looking around for someone to make me a blank System 1 panel and the local shops want an arm and a leg. At this point I'm seriously thinking about just buying a sheet metal brake and learning to use it.

[DrewKaree]

I wish... I've been looking around for someone to make me a blank System 1 panel and the local shops want an arm and a leg. At this point I'm seriously thinking about just buying a sheet metal brake and learning to use it.

Dire, I know you don't drive, but there's a Harbor Freight in St Francis down by the airport, and I KNOW in their catalog they sell a $30 brake that someone else here has used.  Check the white pages and give 'em a call to see if they sell it in the store and take a run down there to see if it'll suit your needs.

[Nannuu]

Are you talking about this one?

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=39103

You'd need the $55 one for a cabinet as it goes up to 30".  I was going to get one but wasn't sure how well it worked.  Can anyone speak for them?

[DrewKaree]

That's the one.  Someone here used one and thought it worked fine, IIRC.

I suppose I could search for Harbor Freight, but I've gotta leave some suspense-type element

[danny_galaga]

Water-based primers and paints will cause MDF to swell; the amount of swelling depends on the amount of water absorbed. (And yes, water-based products behave like water because they contain ... WATER!) If you brush on the paint, you will get more swelling than if you spray, for instance. The effect may not be noticeable in your particular application, though, so a reasonable idea would be to test a scrap piece with the desired paint/finish. Also, some grades of MDF (yes, there are different grades) will be more absorbent than others.

If you want to paint your MDF cabinet with water-based latex, go right ahead. Just realize that you'll be spending some extra time sanding between coats to get the same finish you'd get if you used a solvent-based system instead.

-- Chris

i dont know about latex ( i have a feeling that its something so cheap and nasty they dont use it here), just use acrylic

[jcroach]

i dont know about latex ( i have a feeling that its something so cheap and nasty they dont use it here), just use acrylic

Latex = water based
Alkyd = oil based
Acrylic = type of latex/water based paint. You can have lots of different types of latex paint; vinyl-acrylic, 100% acrylic and alkyd-modified latex.  It all has to do with what the actual paint resin is made out of, not the binding material.  The binding material is always either water or oil.

Check out this link.

[Zakk]

i dont know about latex ( i have a feeling that its something so cheap and nasty they dont use it here), just use acrylic

Or just use good ole lead-based paint.  Can't go wrong with lead! 

[armax]

Everyon who has painted MDF with water based latex without ill-effects, raise your hand, *raises hand*.  Latex, doesn't have enough water to swell MDF.   There is moisture everywhere, MDF is more susceptible to larger amounts of water than some material.  It doesn't mean a drop of water is gonna turn your cab into a pretzel.  Plenty of people here have used latex on mdf....

[snedger]

Hello
Make sure to use proper MDF primer - 2 coats and lightly sand between applications.
If you don't then the MDF will absorb tons of paint - I made an MDF shoe rack once and painted without priming and it took two weeks for the paint to dry!
The first primer application will raise the MDF slightly and so light sanding will ensure the smoothest possible surface. 2 coats of MDF primer, sand in between, then gloss spray paint might just get you a mirror finish!

Regarding thickness of materials. I suppose it depends on where the machine is situated. If it's in an arcade taking abuse then use thick materials. If it's at home and you can remember not to punch the thing, then a good frame surrounded by even 4mm ply would be ok - although I would still put some thick stuff where your feet could kick. It would also depend on the size of the monitor. An LCD wouldn't need much strength, but a huge CRT would def be better off in a full thickness panelled cab. I would also use thick panels if the cab was being wheeled around a lot.
But then you have to conside that thicker means better sound insulation, but thinner might mean slightly better heat dissipation.
Cheers
snedger