Not a bad idea. Festool utilizes MDF in their MFT tops. They have countersunk holes in the top and it fastens from the top with 4 bolts, 1 near each corner.
EDIT: I did wax my FMT top initially. Pro's: Glue doesn't stick. It helps if you set a wet beverage on it. Con's: VERY slippery, you better have cat-like reflexes - the first couple times I used it I caught a track saw and a Domino before they hit the floor by a split second.

 

I used 1/4" hard board on my assembly table screwed to 3/4" mdf ten years ago. I applied wax to the surface to resist glue etc. Still going strong

 

It depends on what you need the top for. For most things, I like plastic laminate. It is very tough, waterproof, smooth, and most liquids don't stick to it very well. For a temporary fix, you could glue it down with brown paper between the plastic laminate and the substrate. That would make it more easily removed.

 

i used contact cement and glued down 1/4'' tempered board, on particle board base, have replaced it a couple times over the last couple decades, easy peasey, little scraping and walla, new glue down. works awesome, good luck, nothing like a pristine top to mess with
rj in az

 

Welcome to the forum. This is a great place with a lot of good opinions!

I ran 3/4 ply once and it lasted a while. It was easy to sand out scuff if I wanted. Tried waxing and shellac, but eventually glue would still stick to it. Switched over to MDF after that. It's flat and smooth and does great with just some waxing. When one side gets too beat up, I just flip it over and it's a whole new bench. And now a days, it's cheaper than ply.

 

Top with a sheet of 1/4" MDF or hardboard. Screw down.

I've seen people lay 1/2" in sections separated by T track, if so desired. Pop them out when you want and replace. Use old ones to route new ones to exact shape.

I don't know how necessary it is. I have a supposedly "replaceable" top on my assembly table. 8 years later its never been replaced........different standards I guess.

 

I have a layered MDF top that I have coated with a few coats of poly. It's been wonderful, crazy flat and not really an issue with glue sticking. I also have 2x4 sides on it to protect the edges and allowed me to put a tail vise and end vise on the table. It's based on a plan from Woodsmith. It's been going strong for several years of pretty decent use.

 

+1 for 1/4" hardboard / MDF on top of a flat, stable top. I screw the MDF down around the edges with brass screws, and apply a coat of tung or linseed oil to help glue or finish scrap off.

My "under top" is an old solid core wood door from an architectural salvage shop - dead flat, solid, and cheap. I wrap the edge with maple.

 

I countersunk a few screws into 3/4" MDF on top of 3/4" plywood. Framed it on two sides with T-track. Then sprayed a coat of lacquer sealer and rubbed in paste wax. Glue drips scrape off pretty easily. I used scrap strips 3/4" plywood when I was cutting up some ply with my tracksaw.

 

My work bench has a hard life, paint, glue, 2 part epoxy, hammer, occasional saw cuts, etc.
I use 1/2" thick tongue and groove boards over a flooring grade chip board base.. If the T&G is slightly damaged it gets a once over with a power plane. If it gets badly damaged it gets taken off for fire wood and a new set of T&G gets put on

 

I've been using MDF for a long time. I had to replace the tops once when the movers got the tables wet, which was no big deal. One table is painted with floor paint for a more durable surface. The other has been sealed little-by-little whenever I have a little polyurethane or oil left on a rag. Both have held up quite well. I have waxed them before, but I've found the slipperiness is not helpful.

 

I have had great success with a top of multilayer MDF. Strong and heavy. Put a hardwood trim around the whole top which is wider by the thickness of my chosen temper hardboard/Masonite top layer. The trim holds the hardboard in place without any glue and covers the ugly edges of the lamination. Easy/inexpensive to change out the top. Made easier by the suggestion of a friend to drill some 1/2” through holes near the edge and to use 3/8” dowel or rod to lift the edge so you can easily get your fingers underneath to remove the old damaged hardboard

 

When I built my 4'x8' work table, I put ⅛" thick sheet of hardboard on top of a ¾" x 4 x 8 sheet of ACX plywood. I fastened the hard board to the plywood with removable spray adhesive and have not screwed it down. I faced the edge of my table with 3x4" ash and made it flush with the top of the hard board so I have some edge protection on the hard board, and a completely flat top. Like others have mentioned, I waxed the hard board with car wax so glue scrapes off easily after it dries. It's been on for over 3 years now and is close to needing replaced. I think the hard board is up to $15 a sheet now at Lowe's.

 

I’m planning a work table and would like to have the option to replace the top as it gets beat up. It would be attached from underneath. Your thoughts on MDF that can be easily replaced as it gets marred and cut. Or, more easily cleaned off melamine and use a sheet of styrofoam when I need to make some cuts.
Appreciate any suggestions. This is my fist table.

My bench top is an old door. When I first built it I bought a damaged solid core door from Lowes. It was $40 I think? That lasted me over a decade and was probably fine. But I got a hold of some doors from a school that was being torn down. It is made from thick strips of pine covered with an oak laminate. It gets heavily used (and abused) and it has help up. If I wasn't fortunate enough to find these doors, I would probably go with MDF and put some kind of finish on it.
When I worked at a cabinet shop, our assembly tables were plywood covered with a 1/4" hardboard like many others have mentioned.

 

I've used solid core door blanks a few times too. They work great but if they get wet, they get wavy. Water gets in through any holes and the particle board inside swells up.

Lately, my favorite wood for an expendable top is "lumber core Meranti" plywood. Some places call it "shop grade". It's not exactly meant to be out in the rain, but it does hold up to a little water since it's all solid wood inside. It stays nicely flat, and it's not very expensive compared to other types of ply.

On mine, I took the time to put a solid wood edge around it, and that makes a big difference. Otherwise, the edges will soak up water like crazy. I also hit it with tung oil, which helps a lot too.

I try not to cut into it (not even with a utility knife), but I do run screws and nails into it all the time. Every once in a while, when I need a super clean surface, I hit it lightly with the random orbit sander.

This top is going on a year old now. It stays outside, under a canopy. Sometimes the rain gets in a little bit, but not too much.

 

For woodworking, laminate and melamine are too slippery, IMO.
For many years, I had a top that was pine boards held with screwed cleats. It was some kind of door from an unremembered source. Since replaced with solid core door with solid edging, which is remarkably flat, and is gradually building up the finish as drips are rubbed in.
The pine top is still fine after maybe 20 years of scraping glue drips, and occasionally being cleaned up with a belt sander, so I don't see the need for building in much replaceability. The primary bench is older than that, and also going strong.

+1 on HammerSmith's approach above.

 

Definitely Melamine. Or spend a little extra on laminate. Glue will scrap off the easiest and they're both durable with laminate being more so than the melamine.

 

My small workbench is MDF. If your workbench isn't real big, check with a cabinet shop for a laminate piece that maybe got damaged.
FWIW, I have made some shop tables from sink cutouts for my drill press and small bandsaw, plus a rolling table for my Rikon router table. Getting ready to make a table for my Rikon grinder for sharpening turning tools.

 

You only want a laminated top if your doing cabinetry, otherwise anything plus a masonite top you can easily replace..

 

+1 on the 1/4" hardboard although I use 5mm underlayment over a double 3/4" plywood substrate. I've done it this way for a while, even before I got more serious about my wood working habit.

There is a lip around the edge and the underlayment just sits on the plywood. When one side gets beat up, I flip it over. Once both sides are trashed, a quick trip to the BBS and I'm good to go again.