Advice on finish or materials for desktop

[Kodi Crescent]

I'm building a home office and I'd like some advice for building the desktop.  I'm struggling with which materials to use and how to finish it so that its attractive and durable.  My desk cabinets are painted white, but I'd like the desktop to be a natural wood color to match the wood of the furniture in the room.  I'm struggling with selecting the desktop materials and finish.

I have 2 areas on the desk.  One is a fully supported area which is 24" x 51".  The other area is 26" x 81", with a 41" open span where the desk is.  My plan is to reinforce the open 41" span with lengths of 1/2" x 1/2" steel box channel sandwiched into the materials.  This area will support a heavy monitor from above, and a steel articulating keyboard arm from below.  The overall material thickness for the desktop was planned to be between 1 1/4" and 1 1/2" thick. 

I know I can buy 4x8 sheets of 3/4" materials in whatever species I desire at the local lumber yards.  I have no experience with, and know nothing about selecting natural materials and natural finishes.  I'm concerned that what I select will not be durable in the long term, and that the finish will wear off, or the desktop will dent and ding easily.  I'm also concerned about sag for the open area.

Any advice on how to proceed?  I really like the natural maple colors, so I'm leaning towards the maple species.

Thanks!

 

[cpw]

The sagulator can help you with determining the appropriate thickness material for sag.https://www.woodbin.com/calcs/sagulator/

I wouldn't worry too much about sag if you can have an apron on the desk, a small amount of vertical wood will pretty much eliminate the sag concern.

 

[sancho57]

MDF Core ply will give you a flatter surface. Its heavy so get help to lift it. then you can add solid edging to match the veneer. Domino the solid edge to the MDF.

bc you are going with a natural finish I like GFs Enduro for a top coat. Id look at flat or satin sheen.

You can brush or spray.

 

[Kodi Crescent]

I've had a lot of prefabricated desks.  Each of them sagged over time. They were made of melamine or particle board materials.

My concerns about sag are due to a static 60lb. load on the 41" span, in addition to an occasional 200lb. load if someone climbs onto the desk. Perhaps it won't be a concern if I'm using plywood materials.

 

[tjbnwi]

For the long span take the time to add a Centerline bracket to the wall at mid span. Epoxying the 1/2x1/2 to the bottom of the top will work if you want to go that route, just not as strong. Make sure the ends of the 1x2x1/2 are supported. I'd use 3 lengths.

Finish, what species of wood will the top be? Have you considered a glue up to avoid using plywood?

Tom

 

[Kodi Crescent]

For the top piece, I'm considering a maple ply Garnica on top of Baltic Birch, or just finishing a layer of Baltic Birch.  I've considered a BB glue up, but not hardwood if that's what you're referring to.  The top will be captive on 3 sides and I don't know enough about the seasonal movement of wood to keep things together long term.

 

[tjbnwi]

If you find the BB pleasant raw, just use General Finish Arm-R-Seal on it, Arm-R-Seal will work well on maple ply also. 

Tom

 

[Kodi Crescent]

I did some testing with the bars as joists across.  The sag was as much as if I didn't have them.

I'll need to use 2 "Centerline Front Mounting Support Plus" brackets to achieve what I'm after.  The underside of the desk has an HVAC return that requires filter service, so I'll mount the supports on the blocking on each side.  It's overkill for the span, but with that obstruction it's necessary.  The unsupported span will be about 22".  I may make the front hardwood edging a bit wider to give the front a bit more "beef".

Thanks everyone for their help!