Best coating for MDF?

[JeffG78]

I am still working on my workbenches/shop cabinets, but I am getting closer to being done. See this thread http://www.bt3central.com/showthread.php?t=35943 The workbench top is made of two layers of MDF and the benches will be used for all types of projects. I see using them for greasy car repair to home projects to wood working projects, so I want to make the MDF as durable and stain resistant as possible.

I was thinking of protecting the MDF tops with an oil base polyurethane, but I could also paint it with deck paint, or ??? The cabinets are made of pine and will likely remain natural with no finish on them. What do you think would work best?

Just for the fun of it, I looked into the epoxy coating that is used on bar tops, but it's just a bit out of my price range. It would cost between $200 and $300 to coat my three workbench tops!

[drumpriest]

My torsion box assembly table is largely made from MDF. I finished it with wipe on poly, and then waxed it so that glue won't stick. I occasionally clean it with mineral spirits, apply another coat of poly, then wax again. It has held up nicely for a few years so far.

[steve-norrell]

My experience with oil-based poly and MDF is not great. I tried using oil-based poly, but got a finish that was mottled with grey spots. It was really quite ugly. When I tried water-based poly, as suggested in the thread, I got a nice smooth finish and the rich brown color that is typical of Rod Kirby's works of art. Check out the thread:

http://www.bt3central.com/showthread.php?t=32791

While the water-based poly goes on MDF well and is almost pleasant to use, I would be concerned about the durability of the finish, especially on a work surface.

I, too. will be interested in the suggestions that are submitted to your query.

Regards, Steve

[RayintheUK]

The workbench top is made of two layers of MDF and the benches will be used for all types of projects. I see using them for greasy car repair to home projects to wood working projects, so I want to make the MDF as durable and stain resistant as possible.

If you're going to be doing car repairs, no matter what you paint them with (including epoxy), the surface will be swiftly compromised, especially if you drag stuff across it - difficult to avoid doing.

I'd be thinking about sacrificial tops for that sort of work, with an oil-based finish for the MDF (Tung oil or Danish oil) which can be "topped up" when needed.

Ray.

[Handy Al]

I copy from another member here. I found some cheap laminate flooring that I put over 2 layer of MDF. Now it looks like I have a oak topped workbench.

[JeffG78]

If you're going to be doing car repairs, no matter what you paint them with (including epoxy), the surface will be swiftly compromised, especially if you drag stuff across it - difficult to avoid doing.

I'd be thinking about sacrificial tops for that sort of work, with an oil-based finish for the MDF (Tung oil or Danish oil) which can be "topped up" when needed.

Ray.

I usually do try to protect a workbench top when working on grimy parts, but I would like to top the MDF with something that can take as much abuse as possible. I hear Nahm talking about tung oil all the time, but I have never used it. What type of protection does it provide? Since MDF is easily gouged, I am looking for something that creates a bit of a hard shell.

[poolhound]

I tend to use the wipe on poly. It creates a very clean surface which is pretty durable for WW. As Ray says I doubt any surface will provide durability if you are going to be dissassembling engines on it. A sacrificial top surface may be the way to go.

For my bench I have a 1/4 lip on the banding and then insert a piece of HB (finished with WO Poly and wax). When it gets too dinged up just replace it for less than $10.

my 2 cents...............

[Pappy]

You said you had 3 workbench tos. Why not dedicate one to mechanical, or limit that type of work to one bench, and cover it with formica?

[Wood_workur]

with epoxy at about $120 for a gallon of resin and a gallon of hardener, I'd think about going with that, for a really durable finish.

[LinuxRandal]

For the automotive one, depending on bench length and your mechanical ability and needs, I would consider making a galvanized sleeve to cover part or all of the top. Mount it to some 1/2" plywood, with a lip that folds over the bench top, then clean it and remove when done.

[RayintheUK]

I hear Nahm talking about tung oil all the time, but I have never used it. What type of protection does it provide? Since MDF is easily gouged, I am looking for something that creates a bit of a hard shell.

The whole point of Tung oil is that it doesn't create a hard shell.

MDF is, as you say, easily gouged. If the surface was hard-glazed, it would fracture, whereas with Tung oil, it won't - and repairs are easy. Because it's an oil, it will waterproof the surface to some extent and also put a sheen on it, enabling you to slide stuff around easier than on "raw" MDF.

The method of application is important to get right. Spread, brush, or rub on a thin coat, leave 15 - 20 minutes, then remove all excess oil. Repeat until you're happy with it. Here's an example of the finish on a mod I did for my Jet OSS:



N.B: If you don't remove the excess, it will be permanently sticky, so don't start this job if there's a chance that you might be interrupted! HTH

Ray.

[cabinetman]

I tend to use the wipe on poly. It creates a very clean surface which is pretty durable for WW. As Ray says I doubt any surface will provide durability if you are going to be dissassembling engines on it. A sacrificial top surface may be the way to go.

For my bench I have a 1/4 lip on the banding and then insert a piece of HB (finished with WO Poly and wax). When it gets too dinged up just replace it for less than $10.

my 2 cents...............

Ray mentioned a sacrificial top, and my suggestion goes along with HB (hardboard), or also known as tempered Masonite. It's amazing the beating it takes without any finish. Oil base poly and wax will provide a non-porous finish. Of course, it's possible to get a surface too slick, when you have trouble with stuff sliding off.
.

[JeffG78]

The more I think about it, the better the hardboard sacrificial top sounds. So, oil base poly works on hardboard? This is likely the route I will go. The only downside is that the corner shelves, which are about 4" lower than the main benchtops, are only single layer MDF and are not designed to have an edge molding. If I add hardboard to the corners as well as the benchtops, then the layers will show. If I don't add it, the color will be different from the benchtops. I don't think I can add an edge molding to the corner shelves without it looking funny or interfering with the drawers.

Here is what I have done so far. All three cabinets are built and in place along with the corners. I still need to add the edge molding around the tops and then build the drawers and doors. What do you think?

[big tim]

My bench is made with 3 layers of 3/4" MDF and one sacrificial layer of 1/4" hardboard(masonite) which I can peel off. I used a water based poly. The bench is now more then 7 years old and the top is due for replacement.
The next time I might just wax it.

Tim

[cabinetman]

Jeff - I'm a little puzzled after seeing the pictures. What your layout looks like is a computer work station. Unless your basement is a lot longer (or wider) than it appears, my question concerns whatever you're going to add to the room to work with, like floor power tools, wall cabinets/shelving, etc.

I couldn't get a real physical impression of the height, but they appear to be like desk height. What are your plans for equipment?
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