Why Use MDF Rather than Plywood

[Southern Dad]

I've always had the impression the MDF was to be avoided and real plywood a better alternative in any sort of project.  Now, I see on here that everyone seems to use MDF.  Is it the difference, price of materials?  I searched but didn't locate any answers to this.

My plan is to build two MAME uprights.  I'll probably use that excellent, yet simple plan on here called Metropolis.  I want a horizontal and a vertical both with 2 player controls.

I'm a real child of the 80's.  High school from '80 - '84, college from '84 - '88, lost my v....  Oh wait, TMI.  Let's just say the 80's were great for me.  I'm also getting an old school Pay Phone for my family room and I've already got an old newspaper vending rack and a two head gumball machine.

[Le Chuck]

There is a plywood out there that has a paper finish like mdf and it is great stuff but I can never seem to find it in the stores.  I steer clear of plywood because getting a smooth glassy finish on it can be a bear in comparison to MDF.  If you're going to laminate the whole thing then ply would be easy and lighter.  MDF is heavy but very simple to work with and routes/carves like butter. 

[Generic Eric]

The price and availability of sheet goods vary based on your location.  I have a local lumberyard, but my nearest Menard's and Lowes are 80 miles away. 

[kahlid74]

Plywood is stronger and the go to source for many things like furniture, infrastructure.  MDF is great where you want a paint/plastic feel to it. 

MDF is used primarily on arcade cabinets because it paints beautifully and routes without issue.  As Le Chuck said, if you play to use a Laminate Plywood would be just fine.

I just recently built a Battletech POD and used Sanded ply and it painted really well.  Two coats Oil based Primer and two coats latex finish.

So you can use Ply if you want but make sure it's a sanded ply.

[spoot]

I just recently built a Battletech POD and used Sanded ply and it painted really well. 

PICS!

[Vigo]

The above comments are spot on, but to be honest, I love ply a whole lot more. I love working with it. I don't have to treat it like hazardous material when cutting it, cleanup is easier, the wood is much lighter, my cabinet feels stronger but on the flip side I end up spending a whole lot longer filling and sanding and repairing edges in order to get a nice smooth finish. It is time consuming to work with. I have grown to like sanded birch plywood these days because it seems easier to work with as far as plywoods go.

I just recently built a Battletech POD and used Sanded ply and it painted really well. 

PICS!

+1

[macattack]

Give MDO a try. It's plywood with a waterproof paper covering that is as smooth as mdf. Same material outside signs are made from.


www. Xtremepinball.com

[PL1]

I just recently built a Battletech POD and used Sanded ply and it painted really well. 

PICS!

+1

Did you guys miss his build thread in Project Announcements?


Scott

[Southern Dad]

Did you guys miss his build thread in Project Announcements?


Scott

Maybe.  Okay, most likely.  Fine, I admit it, I missed it.  Thanks for pointing it out.

[PL1]

The comment was directed at Vigo and Spoot asking for pics, but I'm glad you enjoyed Kahlid's build.   


Scott

[Le Chuck]

Give MDO a try. It's plywood with a waterproof paper covering that is as smooth as mdf. Same material outside signs are made from.


www. Xtremepinball.com

That's the stuff I was talking about.  Great when you can find it!

[macattack]

Most good lumber yards can order it it stock it. For me its northville lumber in Michigan.


www. Xtremepinball.com

[Vigo]

Did you guys miss his build thread in Project Announcements?


Scott

Yeah, I generally can't follow project threads from work due photos getting blocked out to my work filters. It's on my radar now so I can follow from home.

[spoot]

Did you guys miss his build thread in Project Announcements?


Scott

Yeah, I generally can't follow project threads from work due photos getting blocked out to my work filters. It's on my radar now so I can follow from home.

Lol, same.

[RandyT]

MDO is great, but the smooth layer is not "waterproof" as a previous poster stated.  It is essentially a high-grade plywood with a bonded MDF-like layer on one, or both sides.  It is used by sign makers (my dad used it extensively in the biz), but the same preparations for outdoor use still need to be done.  Priming and fully sealing all exposed surfaces is a must in this type of application.

The major drawback to MDO is price and availability.  It's probably about $80 for a sheet of 3/4.  Due to the high cost, it's a very specialized market, which means not too many places carry it.

MDF makes for great panels, and cabinets as well, so long as proper assembly techniques are used.  Never try to screw directly into an edge, or make cuts which leave small and unsupported features.  Other than that, and perhaps a little more weight (usually a good thing for a free-standing unit) there's not much advantage in using  MDO or plywood over MDF, and MDF has a number of advantages over these materials.

[kahlid74]

Also, if you use MDF make damn sure you've got proper ventilation for cutting/routing and use a mask/Eye/Ear protection.  The particles of MDF aren't hazardous but the FINE DUST particles it generates are deadly to your lungs.  Repeated exposure can be bad.

[RandyT]

Also, if you use MDF make damn sure you've got proper ventilation for cutting/routing and use a mask/Eye/Ear protection.  The particles of MDF aren't hazardous but the FINE DUST particles it generates are deadly to your lungs.  Repeated exposure can be bad.

Absolutely.  When I first started using my CNC router so many years ago, I didn't think much about it.  But after the first day of coughing, irritated eyes, and cleaning up the fine layer of dust that literally went everywhere, even with a dust collector running, I quickly learned.  Routing is much worse than sawing, but proper protection is always a must.

[nemesismachine]

MDF is used primarily on arcade cabinets because it paints beautifully and routes without issue.  As Le Chuck said, if you play to use a Laminate Plywood would be just fine.

Original cabinets had vinyl glued to em, giving the smooth feel.  Just like kitchen countertops or cabinets.  My MKII cabinet is all plywood, only way you could tell otherwise is to peel the T-molding back or pull up the CP.  The slot cuts the same as MDF.  The cabinet is also lighter than an MDF cabinet, as all those that have built with MDF can attest to.

[michelevit]

Cutting and routing MDF makes a hurricane of micro-dust.  Its also much heavier.
I no longer make cabinets with it for this reason. I only use 3/4 or 1/2 plywood.
As far as paint goes, I use a HVLP gun to lay down primer and paint. It makes an authentic finish.