Router Table Top Construction

[Jim VanBramer]

I'm in the process of making a new router table, and I'm at the stage where I need to decide how to make the top. I was considering 2 layers of 3/4" MDF, and a layer of Formica for the top surface. First, is MDF a good choice for the base material? Secondly, I know when you use plywood they recommend putting the Formica on both top and bottom surfaces ... would this be a necessary step if I were to use MDF?
As usual I look forward to all your expert advice! :D
Thanks.

Jim V

[Greg Mann]

My RT is exactly as you described, 2 layers of 3/4 MDF with laminate top and bottom. Is it necessary to do both sides? Most sources say yes. My take? After putting that much effort in, why would you want to take the chance that it might warp? The cost of the laminate is minimal in the big picture and you will have all the stuff in place for doing it because you will have already done the first side. The second side is a no-brainer as far as effort is concerned. FWIW, I rabetted both sides of the opening for the insert so that if I did something stupid and damaged the top I could just flip it over to use the other side. Again, everything is there, it's just another 20 minutes work. My top is dead flat after 2 years.

Greg

[Ken Waag]

Jim,

Formica makes for a tough smooth top surface. No need to do the underside. MDF is good for your substrate in that it is very flat (more so than plywood) The trick is to keep it straight as it will sag under any considerable weight.

Will you be using a router table insert/mounting plate? If so, I might recommend a single layer of the MDF with stable hardwood (i.e. Maple) bracing. Joint flat edges and glue & screw them to the MDF. If thickness is not a concern 1 1/2" bracing would give good rigidity. You can do a skirt around the perimeter and braces spanning across at points just wider than the insert plate. This arrangement would be stiffer and stay flat better than 2 layers of MDF.

If you get a look at the extension tables that come with cabinet saws, that's what I'm describing.

For esthetics, you can use formica to dress the sides if you like.

Hope that is some help. good luck and have fun,
Ken

[Dave Falkenstein]

This might be more than you ever wanted to know, but...

I prefer MDF for a router table top. MDF is usually very flat and the surface is smooth. Here's how I made mine. Use two pieces of flat 3/4 inch MDF, and cut them an inch or so oversize in both dimensions. Make it easy on yourself by cutting one piece just a bit smaller than the other in both dimensions - this trick will make it easier to trim to final size later. Predrill for screws that will be used to pull the two surfaces together during glue-up. Countersink for the screw heads - the heads will be covered by Formica later. Avoid screws in the area where the insert plate opening will be cut. Mark the plate area and predrill for screws about an inch or so beyond the outside of the hole. Coat one side of both pieces of MDF with solvent-based contact cement and let it dry - MDF absorbs contact cement, so two coats works better. Apply a second coat of contact cement and follow the instructions on the can for setup time. Lay some dowels across one piece and lay the second piece on top of the dowels - holding the two cemented surfaces apart. Line up two edges as well as you can, trying to keep any overlap all in one direction - the object here is to leave two edges that are straight and square with each other for trimming to size later. Remove the dowels starting at one end and roll the top piece to create a bond. Add screws to the predrilled holes, bonding the two halves over the entire surface. Cut the top to size, using the two straight and square edges as guides - I cut mine on a table saw. Edge band the edges of the top with hardwood - I used 1/2 inch thick maple - leaving the edge banding proud on both sides of the top. I used the two coats trick and yellow glue for the edge banding. Trim the edge banding flat with the top using a straight laminate trim bit and/or a sander. Apply Formica to both sides of the top, using two coats of contact cement on the MDF as above. Trim the Formica using an angled laminate trim bit, cutting slightly into the edge banding. Rough cut the plate hole with a jig saw and finish the inside of the opening to size with a long straight bit in the router and a straight edge guide. Finish the plate hole with a rabbet exactly the size and depth of your plate - you can usually buy a template for the plate wherever you get the plate. Add small flat head screws where the plate adjusting screws contact the MDF in the rabbet, to prevent the adjusting screws from denting the MDF. Viola - a router table top.

[Ted Shrader]

Jim -

Recommedn you put laminate on both sides. The humidity in your neck of the woods would make the bottom surface want to move. Wrap the edges of the table with wood trim or more laminate to protect them.

Ted

[JayStPeter]

Mine is 2-layers of MDF with Formica top/bottom also.

At a company I worked for, they got some workstations made by a local shop. They made the tops out of MDF with formica on the top. A few months later, we had potato chip desks. They started putting some material on the bottoms too.

Jay

[John Daugherty]

I made my top out of 2, 3/4 pieces of MDF with formica on the top and several coats of shellac on the underside. It’s been about a year and no movement has occurred.