Family Room built-in entertainment center & cabinets

[GaryA]

So, I'm finally getting started on my family room built-in project. This is new to me. I have a recessed area right next to fireplace (will have stone and a raised hearth when I'm done) in the family room that will house all of my audio/video components in base cabinets. On the top of the base cabs will be my 55" Sony HD rear-projection set, and a speaker on each side with a frame and speaker mesh covering it. On top of that (still somewhat undetermined as far as design), will be my center channel speaker, etc. The measurement of the recessed area is 110"x76.5"x24". See photos (as you can see, my daughter has taken over the house), and my "renderings".

The cabinets I was going to make from MDF, and they will be painted white. I've begun by building a 2x6 (slightly ripped down) torsion box base. The MDF base for the cabinets is cut to size, and I was going to dado for the left, right and center supports (was thinking of putting two pieces of MDF in the center to support the cup hinges).

I've never done a project like this, so I certainly have questions. Let me throw a couple out to you guys:

1. See any flaws so far with the plan?
2. Would you use hardwood banded MDF for the top, or should I use plywood?
3. Heat is a concern with the receiver, etc...so I wanted to vent, and install some small low voltage cooling fans in the cabinet - any ideas
4. I bought a Porter Cable HVLP PSH1, and tried/tested it out for the first time with a Zinnser oil-based primer. I'm getting spatter, and looks like I may need to use a different nozzle set here?? Should I just roll it??
5. I was going to use the oil based primer, then a Porter white semi-gloss latex (to match basesboards)...anything over that? Should I not use latex?


Thanks!

[scorrpio]

Rear projection TVs generate a lot of heat, you'll need that space actively vntilated. You need an intake near bottom and an exhaust near top.

Intake can be accomplished by venting the toekick. I would pretty much remove the toekick board and cover it with speaker mesh to match the speakers. Remember - being an intake, it will attract dust, so you'll want to install a filter behind it, an make mesh removable so filter can be cleaned. Depending on what is behind that wall, intake grille can instead be installed near the floor on the other side instead - making it to look 'in place' on that wall, and again, providing filtering.

For exhaust, several options. It looks like you want an open shelf at the top. You can make this shelf about 6" less deep than the recess and vent through the shelf back. You can put in several vents, also covered by speaker mesh, to align with the lights. Install fans behind those vents.

Take a look at http://www.directron.com/casefans.html

http://www.directron.com/a2330.html looks like a good fan choice - very quiet. You might also want to consider a controller like http://www.directron.com/doc5.html

[GaryA]

Man...I just can see that looking good (although it does make sense about the toekick). I like the fan idea, but aren't these fans lower voltage, and need some type of adapter/transformer to work?

Anybody have any feedback on the top? plywood or MDF (case is MDF)?

Thanks

[Cheeky]

http://www.activethermal.com/

what is on the other side of the walls to this room? can you vent to a closet or garage?

[GaryA]

http://www.activethermal.com/

what is on the other side of the walls to this room? can you vent to a closet or garage?

Actually half of the space (when facing it, the right half) has my wife's walk-in closet behind it. I know the TV heat was mentioned. I think that will be actually be fairly well ventilated, and isn't generating as much heat as I have coming from below where my receiver, FIOS box, Apple TV, etc are. I can cook an egg in there. Are you thinking install a fan intake and then an exhaust both in the wall of the closet?

[GaryA]

Quick side question - going to BORG today...what sheen paint would you guys use on a project like this? I was thinking semi-gloss...whats the rule of thumb...glossier will show more flaws?? Thanks

[JimD]

Gary,

More gloss will show more flaws but you should be able to sand smooth.

I have cabinets on either side of my fireplace with the TV over top of the fireplace (an unvented gas unit). The base cabinet on the right has the receiver, CD/DVD player, cassette, DVD/VCR recorder plus some drawers for storage. I did not have sufficient storage so I built another end table to hold DVD/CDs/VHS tapes. The top of my cabinets is marble tile which matches the fireplace surround. It is more durable than wood would be. You need a double layer of plywood, maybe two layers of MDF would work if the supports underneith are close enough together. It can't flex. The front edge is oak biscuited to the wood underlayment. It's easier than you may think but you need to borrow, rent, or own a wet saw to cut marble or granite tile. My marble is black and I just butted it together and pushed a little unsanded grout into the small crack.

I did not vent the cabinet where the sterio stuff is but I have to leave the doors open when using it so I can use the remote. I made the doors so they go back into the cabinet so it looks OK with them open. That seems to keep the equipment adequately cool - I have had no problems in 5+ years of use.

[scorrpio]

Your components seem to be stashed in the unit below the TV, meaning their airflow is so-so, but TV currently has a very large dissipation area, so you don't currently notice much heat coming from it. But if you put that TV into a recess, and close off the gaps all around it, you will have an oven. Even for LCDs, a setup like that is not recommended - an a rear projection, with its high-powered lamp, is gonna cook. If behind that wall is a closet, I'd think twice before using it for exhaust/intake - unless it's a real large closet, and there won't be clothes obstructing the vents.

For the fans/controller I linked, you'll need a 12V source - generally, these things are designed to plug into a PC power supply. But any 12V adapter will do as long as it can provide 4-5amps.

[cabinetman]

Your project doesn't represent a big problem. As for the construction, I would build it as a slide in. The base cabinet can be made with two ends and a center divider. You won't need any fancy joinery if you are using MDF. The three standing pieces are attached to the floor of the cabinet. The toe kick could be made as a loose piece, but not as involved as you drew. It will sit under the floor all the way around with just a front and back, and two sides. You might just gusset the corners to keep it relatively square.

On top of the ends and the center (which will all be the same height) run cross rails front and back across the three pieces and glue and screw them to the verticals. They should be 3/4" plywood or solid wood. Lay them flat and make them about 2 1/2" to 3" each. Make the top from 3/4" MDF and put a 3/4" buildup under the front and back and middle of the top underside to coincide with the cross rails.

Hot air rises all on its own. You would be surprised how much air gets passed overlay doors on euro hinges, with door bumpers. You could mount fans inside the base sections exhausting upward and have corresponding ducts to the top shelf. You don't have to move a lot of air, as long as there is some transfer. As for the TV itself, if you have a small gap around it for circulation, and some behind it, that may be sufficient for cooling. You will need some room to get it in and get it out.

As for paint, You could use a semi-gloss acrylic, from the primer to the finish. Or, an oil base. In either case, allow a long time for the coats to cure, even if they may feel dry to the touch.

Some spray guns have too large an orifice or too small depending on the viscosity of the spray material. You will need sufficient pressure to atomize the mixture to keep it from spitting and splattering. Water base will dry faster, but you will need to thin it and apply several coats.
.

[GaryA]

Thanks fopr the great feedback guys...very helpful.

Making the top now...I lightly sanded and glued 2 sheets of MDF together and am cutting it to size. Should I screw them together from underneath also...or is the glue enough?

I was planning to put a poplar edge over the MDF, and maybe just give it a simple roundover to soften it. Should I biscuit this into the MDF, or can I also get away with glue & clamps?

[Garasaki]

I think it may be important for you to understand that glue (when used properly) is stronger then screws or biscuits.

Screws are used to provide "clamping pressure" for 2 surfaces.

Biscuits primary purpose is to keep 2 surfaces aligned.

A properly glued joint will be much stronger then a joint that just has screws, or just has biscuits.

A properly (just) glued joint will be much stronger then a joint that is poorly glued and screwed, or poorly biscuited and glued. (at least all this is true for "real" wood...perhaps different for MDF?)

Many people, myself included at one time, do not really understand this. Most people believe running a few screws thru something can provide more strength then glue. In a way, it's even intuitive and appeals to the "mechanical" nature of man. but it is not true at all.

I can point to some cedar for a trellis I made a few weeks ago...I glued some blocks onto the sides to use to pound it into the ground. Big surprise, when I was pounding, the joint failed. It did not fail at the glue though...the wood actually delaminated about 3/16" of an inch "into" the block, away from the glue...in other words, the glue, and about 3/16" of an inch of the block, remained attached to the main trellis, as the rest of the block broke off. The glue was stronger then the wood.

So, for your laminated MDF, there is no need for screws. Especially after it's been glued.

I can't commit specifically on your poplar edge, other then to say biscuits may be useful in helping the poplar stay aligned during glue/clamp up, or they may not. And it may be challenging to clamp this in place...if possible you might try to put the edge on first, then install into it's final place.

[docrowan]

I think it may be important for you to understand that glue (when used properly) is stronger then screws or biscuits.

John,

You beat me to the post. The time for screws during glue up is before the glue has dried. I learned how powerful adhesives can be when I painted the top of a shelf made up of three different sized boards (I was 19 and had never heard of a glue up.) My intention was to be able to pull these boards out separately in order to move the shelf. After two coats of paint on the top only, the boards were permanently welded together. Mind you, it was just the paint that seeped between the butted together edges. Paint, not glue and just seep through, not fully painted on the edges. I tried pretty hard to pull the boards apart and couldn't budge them.

MDF is supposed to pretty easily glue starve a joint on the edges due to the porosity, but the surfaces are very dense and will hold glue well.

[LarryG]

I was planning to put a poplar edge over the MDF, and maybe just give it a simple roundover to soften it. Should I biscuit this into the MDF, or can I also get away with glue & clamps?

Biscuits will be a great help in maintaining alignment, and will act like small loose tenons, but they aren't really necessary for strength.

Another way to hold the pieces in alignment is to drive a few small brads into the MDF edge and nip off the heads with wire cutters so that about 1/16" of the brads are left protruding. These will keep the poplar edge from sliding around on the wet glue as you do your glue up.

Or, you can apply an over-wide edging and flush-trim it to the MDF later. (I usually use this last method when possible, but have done all three.)

It's a good idea to apply sizing to the edges of MDF before applying the actual coat of glue. Size is a thin coat of yellow glue (some people thin it with water) that is brushed on, allowed to dry to tackiness, and the excess scraped off. This semi-seals the porous MDF edge and keeps it from sucking up all the glue that is applied when you do the actual assembly.

[cabinetman]

Thanks fopr the great feedback guys...very helpful.

Making the top now...I lightly sanded and glued 2 sheets of MDF together and am cutting it to size. Should I screw them together from underneath also...or is the glue enough?

I was planning to put a poplar edge over the MDF, and maybe just give it a simple roundover to soften it. Should I biscuit this into the MDF, or can I also get away with glue & clamps?

Biscuits do not insure alignment. Their intent is to keep the two members from pulling apart. You may need the applied piece to slide somewhat to get "perfect alignment". Glue and clamps work very well, and a pin nail or two if necessary.
.

[JimD]

I have to disagree about biscuits not adding strength. For an application like an edging, using biscuits will add contact area for the glue so it will add strength. I agree with the comments about needing them, however. You don't. Unless you cannot get good contact between the edging and the MDF. They are a quick and easy insurance policy, however. I used them when I put an oak edge on the countertop for my cabinets.

Jim