Why MDF over Plywood?

[Unstupid]

Am in the very early stages of planning a small bar top arcade and next on my list is what material to use to build the box.  I notice a lot of people use MDF.  Why use it over say Plywood?  If you had a choice and cost was no issue would you still use MDF?  I was initially planning on using 3/4" marine plywood or AA/AA cabinet plywood.  I plan on painting it myself.  Mostly black, some red.  I was planning to bog it and sand down to 600 or 1200 then prime and paint a few times with some sanding in between.  then finish it off with a polish.  Would It be less work with MDF?  Thanks for any advice.  BTW no melamine MDF available here in Hawaii. 

[jimfath]

I'm with you. I'm early in a project and trying to weigh the options of one vs the other.

There is this thread. Some folks mention MDO as well
http://forum.arcadecontrols.com/index.php?topic=102064.0

[Donkbaca]

Mdf is cheaper, it's easier to work with, and its smooth so it's easier to paint. Plywood is lighter, stronger and more water resistant

[Benevolance]

MDF is really easy to work with if all you've got is a router.

[Rick]

My cab has a lot of rounded edges which need to meet smoothly with other edges that cannot use t-molding.  Thus, I need a smooth surface connection with no visible seams.  MDF is much, much easier to finish in that regard.

[SammyWI]

My cab has a lot of rounded edges which need to meet smoothly with other edges that cannot use t-molding.  Thus, I need a smooth surface connection with no visible seams.  MDF is much, much easier to finish in that regard.

My cab will have an area like this on the CP box, so for that I'm using MDF.  The rest will be MDO - smooth exterior for painting, plywood in the center for strength, weight, etc.  Also, MDF makes a lot of dust and is pretty hard on tools (dulls things quick).  MDO costs more though.  Picked up some yesterday and it was $50 a sheet.

[Blanka]

I don''t get the weight problem. MDF at 12mm is great and weighs the same as 18mm Ply, where Plywood at 12mm would be totally no option. Plywood is incredibly moisture sensitive and curves a lot. MDF is just flat, flat and even more flat. It paints perfect. Just use good tools to glue MDF together. Either lammello pieces or wooden pins. No screws or wooden beams for corners needed, just glue.
Only do plywood on sides you want to apply T-molding on and where HPL laminate is used, as trying to get T-molding on 12mm sides stinks. But nobody demands you to use T-molding. Guess you wont put it in a bar and want it to use the cheapest way to get it bar-proof.

[Ed_McCarron]

It's easier to load in a truck?

(Sorry, I never get tired of that one...)

MDF is smoother and more consistent, structurally.  No voids.  That's all I got.

[dithrin]

MDF typically paints better.  It also does not expand and contract with the humidity as much as plywood does.  This means you wont have panels/ joints cracking.

[Donkey_Kong]

and something that is hardly discussed here...Trupan, or 'lightweight MDF' which is even better that regular MDF.

the good
~Lighter Weight
~No Formaldehyde Added (that nasty chemical they use to glue regular big box store MDF)

the bad
~very hard to find
We get ours from Saint Croix Valley Hardwoods in White Bear Lake Minnesota. I believe they are the only supplier in the upper midwest.

'Trupan' is the imported version and it comes from Chile, it is made from pinewood and non toxic glue. I believe there is one other manufacturer that I have a hard time getting info on. I think it is Sierra out of California.


Another better alternative to MDF and plywood that is usually readily available in big box stores...MDO. Its a smooth grade of plywood and uses water resistant glues. The downside for MDO is price...probably double that of the former options. Worthi it in my opinion though, it will give you a much better finish vs regular plywood when painting and friendly dust than mdf.

[ChadTower]

It's easier to load in a truck?

(Sorry, I never get tired of that one...)

One of these days, Alice, one of these days... POW.  STRAIGHT TO THE MOON.

[Hoopz]

It's easier to load in a truck?

(Sorry, I never get tired of that one...)

One of these days, Alice, one of these days... POW.  STRAIGHT TO THE MOON.

I missed this thread until now but when I saw the subject, I knew there'd be comments.   

[Vulgar Soul]

According to most, MDF is more consistently smooth, square, flat, and is cheaper then even B grade ply. Downside is its weight and nasty chemicals when working with.

I used plywood for my first build, but I think I'll be switching to MDF for future ones. I've bought plywood that turned out to not be square on some corners, and were warped. Really irritating to deal with.

[Unstupid]

I Think I'm going to use MDF from now on too... I have some really good plywood but it is very irritating to deal with.  as I'm sanding I'm constantly running into places where the plywood is splintering on the cut lines... now I'm going to have to go back an fill these little voids in with wood filler then resand... seems like a lot of unnecessary work....  Uhh... thinking about going back and recutting everything on MDF...

[yotsuya]

I wouldn't mind trying MDO myself. Just need to find it locally.

[PIZZ]

Im starting a build with hardwood ply. Its lightweight, sturdy and easy to cut. You get no jaggies like cheeper ply. Drawback is its a little pricey, a little less then double what MDF costs.

[GregD]

I f you want to use plywood and plan on painting the cabinet then use MDO.  If you want to use MDF it is worth it to spend a little extra and get the lightweight MDF.  33% less weight and less dust.

[BobA]

MDO is the best but harder to find.  MDF finishes very well.  Plywood is lighter but sometimes hard to finish and build with.  Depends on the grade you are buying.  Cheaper usually means more problems with ply.

[Kangum]

mdf has no texture like plywood. so its paint is smooth. plywood your going to see the wood grain through the paint no matter how much you sand

[jimfath]

mdf has no texture like plywood. so its paint is smooth. plywood your going to see the wood grain through the paint no matter how much you sand

Not even with primer and coats of glossy finish?

[GregD]

mdf has no texture like plywood. so its paint is smooth. plywood your going to see the wood grain through the paint no matter how much you sand

Not even with primer and coats of glossy finish?

It just isn't worth the effort.

[yaksplat]

mdf has no texture like plywood. so its paint is smooth. plywood your going to see the wood grain through the paint no matter how much you sand

Sanded birch plywood has no visible grain.

With a layer of primer and two coats of paint you can get an amazing finish.

[kahlid74]

I've only ever used MDF for my cabs.  The quality of plywood I find at the Big Box stores is sub par and the great lumber stores in my area have all closed.

[Well Fed Games]

If I was building a whole cab, I would not use MDF, as it really is pretty heavy. But it all depends on what you want to make and how you are going to move what you made when you are done.

[yaksplat]

One thing that i did notice after building 3 cabs with plywood.  The plywood will start warping if left on edge for a while.  First cab was completely square.  Next one i had compensate a little.  The last one i had to add in a lot more wood to keep the thing square.  I have 3 sheets that i'm going to take back to lowes.  They're way too warped to work with.

If you use plywood, use it right away or store it flat.

[kahlid74]

I was building something for my woodshop and I found sanded oak plywood at home depot.  It doesn't warp and routes fairly easy, but is twice the cost of MDF but feels like half the weight.  I think I may build my next cab out of it.

4x8 MDF = 17 bucks
4x8 Oak sanded Plywood = ~40 bucks

[Vigo]

I am currently juggling between getting some nice sanded plywood or melamine laminate board for my next project. For $25 bucks for a sheet of melamine, its really tempting, but I am paranoid about chipping on the edges. I'd like to think that switching to a saw blade with with a much higher tooth count would resolve that.

[PIZZ]

I was building something for my woodshop and I found sanded oak plywood at home depot.  It doesn't warp and routes fairly easy, but is twice the cost of MDF but feels like half the weight.  I think I may build my next cab out of it.

4x8 MDF = 17 bucks
4x8 Oak sanded Plywood = ~40 bucks

Im using a hardwood ply i got from HD for my build. Its got a 3-layer ply with the center layer oak sandwiched betwen birch it looks like. Nice light and sturdy.

[alfonzotan]

I used MDF for my control panel (which was stand-alone for the better part of a year), and switched to plywood for the cab.  All the dust from working with the MDF drove me nuts (insert pirate-with-a-steering-wheel-in-his-pants joke here), and weight was also a contributing factor.  The plywood (after digging through the stacks for flat sheets, which was neither easy nor fun) worked out quite well, and I'm happy with the build. 

Easy decision in my case, since all my exterior surfaces were to be laminated, so I didn't care about if the ply surface was on the rough side.  For a painted surface, I can certainly see going with MDF instead. 

[yotsuya]

All the dust from working with the MDF drove me nuts (insert pirate-with-a-steering-wheel-in-his-pants joke here

 

[kahlid74]

All the dust from working with the MDF drove me nuts (insert pirate-with-a-steering-wheel-in-his-pants joke here

 

I plan to post to the woodworking forum in a day or two about this and how to resolve it.

[Steve248]

It has all been said before but just wanted to explain why I have chosen plywood over MDF for my project.

Basically it comes down to safety, I have a family I dont want them breathing in the particles. It does not matter how hard I try with a vacuum on my router/circular saw etc, there is still dust everywhere.

Having said that, for someone with as little experiance as me, plywood is a real pain in the neck. When you cross cut it splinters so easily, I now make a really really shallow cut then a slightly deeper one then through the whole way. I am now getting much better at it.

I guess the real secret to great clean cuts with ply is avoid cross cuts at all costs. I am going to try and think things through in future and hopefully improve things.

So in a nut shell, yes MDF is much easier to work with but at what cost?

[wp34]

I used MDF for my current build.  Besides the dust I've been real happy with it.  The stuff really likes to be routed. 

For the front, top and back panels I've had a few issues with MDF splitting when I screw it in place.  This is even after pre-drilling.  I may go with plywood or MDO for those pieces next time.

[kahlid74]

It has all been said before but just wanted to explain why I have chosen plywood over MDF for my project.

Basically it comes down to safety, I have a family I dont want them breathing in the particles. It does not matter how hard I try with a vacuum on my router/circular saw etc, there is still dust everywhere.

Having said that, for someone with as little experiance as me, plywood is a real pain in the neck. When you cross cut it splinters so easily, I now make a really really shallow cut then a slightly deeper one then through the whole way. I am now getting much better at it.

I guess the real secret to great clean cuts with ply is avoid cross cuts at all costs. I am going to try and think things through in future and hopefully improve things.

So in a nut shell, yes MDF is much easier to work with but at what cost?

You get dust with Plywood too so don't trick yourself into believing you're better off (not as much as MDF but in an enclosed space it's still there).  I just went through this in my house and the place you're now at is understanding your workshop and understanding how serious you are about your health and your families.  If you're super serious and you're workshop is in an enclosed area, then you do three things:

• Air Filtration unit to circulate the air in your workshop about 5-8 times per hour.  See my thread here about how to make you're own - http://forum.arcadecontrols.com/index.php?topic=117883.0
• Vacuum direct attachment to any saw/router you're working with.  Picks up a good portion of the big chunks and gets a good amount of other dust too.
• Personal Respirator for when you're working on the wood.  The above two should take care of just about all of the dust/debris but for you working in the direct vicinity, your intake breath will be grabbing them before the above two will.  So you need to be protected too.

Just like you, even with a vacuum I still had dust everywhere.  Since I built the Air filtration unit I no longer have dust everywhere.  Also, fine woodworking dust clogs the pores in your lungs, making you more susceptible to bacteria/viruses.  Before my air filtration unit I had been more sick this year then ever before.  After, no more colds.

Also, I've cut Plywood without any chipping by using Freud Diablo finishing blades.  They cost more but are super freaking sharp and rock cuts.  Also, don't get just any plywood.  Spend the money and buy stuff like Sanded Oak.  The stuff doesn't chip even with crappy blades in my experience.

[Steve248]

It has all been said before but just wanted to explain why I have chosen plywood over MDF for my project.

Basically it comes down to safety, I have a family I dont want them breathing in the particles. It does not matter how hard I try with a vacuum on my router/circular saw etc, there is still dust everywhere.

Having said that, for someone with as little experiance as me, plywood is a real pain in the neck. When you cross cut it splinters so easily, I now make a really really shallow cut then a slightly deeper one then through the whole way. I am now getting much better at it.

I guess the real secret to great clean cuts with ply is avoid cross cuts at all costs. I am going to try and think things through in future and hopefully improve things.

So in a nut shell, yes MDF is much easier to work with but at what cost?

You get dust with Plywood too so don't trick yourself into believing you're better off (not as much as MDF but in an enclosed space it's still there).  I just went through this in my house and the place you're now at is understanding your workshop and understanding how serious you are about your health and your families.  If you're super serious and you're workshop is in an enclosed area, then you do three things:

• Air Filtration unit to circulate the air in your workshop about 5-8 times per hour.  See my thread here about how to make you're own - http://forum.arcadecontrols.com/index.php?topic=117883.0
• Vacuum direct attachment to any saw/router you're working with.  Picks up a good portion of the big chunks and gets a good amount of other dust too.
• Personal Respirator for when you're working on the wood.  The above two should take care of just about all of the dust/debris but for you working in the direct vicinity, your intake breath will be grabbing them before the above two will.  So you need to be protected too.

Just like you, even with a vacuum I still had dust everywhere.  Since I built the Air filtration unit I no longer have dust everywhere.  Also, fine woodworking dust clogs the pores in your lungs, making you more susceptible to bacteria/viruses.  Before my air filtration unit I had been more sick this year then ever before.  After, no more colds.

Also, I've cut Plywood without any chipping by using Freud Diablo finishing blades.  They cost more but are super freaking sharp and rock cuts.  Also, don't get just any plywood.  Spend the money and buy stuff like Sanded Oak.  The stuff doesn't chip even with crappy blades in my experience.

A lot has happened since my last post. Chipping is no longer an issue at all, I have bought a Festool TS 55 saw and it has literally changed my life! What an incredible piece of equipment, perfect cuts, perfectly straight, really fast, and no chipping even on crappy quality ply. Unfortunately it does cost a few quid but I just love cutting wood now, it is a pleasure so worth every penny.

Anyway, it also has a great quality filtration system which I have not bought yet, I am using my existing vacuum which does an OK job but the festool sytem gets rid og 98% + so once I have it I think I will be happy working with any material including MDF.

I have started my project now. I will post pictures as soon as I can.