Author Topic: Ply or MDF For MFT Top? (Read 2033 times)

darita · « **on:** February 28, 2023, 09:49 AM »

I want to make an MFT top, however I'm not sure which material is best to use, MDF or Ply? If ply, then which ply?

jeffinsgf · « **Reply #1 on:** February 28, 2023, 11:03 AM »

I prefer MDO plywood. It has a resin impregnated paper as the surface veneer. It's very smooth and takes an oil or wax finish very well. It's what most billboards are made from. It's relatively flat and stable. If you're somewhere that has Menard's, they keep both 1/2 and 3/4 in stock. The Blue and Orange boys don't carry it, but can order it. Any pro plywood supplier should have it. If I have one gripe about it, it is that it occasionally has some small voids in the interior plys.

I made my current MFT top from it, and it has held up much better than my previous MDF top. I also used it for my miter station top and it has held up to sliding rough sawn stock across it better than I could have imagined.

More expensive than MDF but quite a bit less than Baltic Birch.

tsmi243 · « **Reply #2 on:** February 28, 2023, 12:49 PM »

MDF, definitely. No splinters.

Richard/RMW · « **Reply #3 on:** February 28, 2023, 01:32 PM »

Agreed, MDO if you can get it, MDF if not.

In my experience, most plywood in just at or even under 18mm thick, MDO/MDF are 19mm+. Many of the dogs (I have most flavors) are 18mm or over in length. If the dog is longer than the MFT top is thick, it becomes a PITA to secure them from below.

RMW

NiteWalkerGR · « **Reply #4 on:** February 28, 2023, 01:53 PM »

I'm in the same boat; my PGS Mk II just arrived and I'll be heading out in a week or so when the weather improves a bit to get the materials for my DIY mft. I decided on MDF. I thought about using plywood but really, MDF is fine. It's cheap(ish) and plenty durable for a work surface, especially if you give it some sort of treatment. I'll be using danish oil on mine.

Coen · « **Reply #5 on:** February 28, 2023, 03:05 PM »

The original top is from HDF. Making one from MDF might be a disappointment compared to the original.

NiteWalkerGR · « **Reply #6 on:** February 28, 2023, 07:44 PM »

Quote from: Coen on February 28, 2023, 03:05 PM

The original top is from HDF. Making one from MDF might be a disappointment compared to the original.

The original tops are made of MDF, not HDF. IIRC festool confirmed this in another discussion here.

bwehman · « **Reply #7 on:** February 28, 2023, 10:42 PM »

MDF, and seal it with some kind of film finish. I use Satin Minwax Poly. Dried wood glue drips just flick right off.

Coen · « **Reply #8 on:** March 01, 2023, 03:10 AM »

Quote from: NiteWalkerGR on February 28, 2023, 07:44 PM

Quote from: Coen on February 28, 2023, 03:05 PM
The original top is from HDF. Making one from MDF might be a disappointment compared to the original.
The original tops are made of MDF, not HDF. IIRC festool confirmed this in another discussion here.

Where?

It's unlike any MDF I've ever seen.

festal · « **Reply #9 on:** March 01, 2023, 06:52 AM »

@jeffinsgf lowe's actually has mdo at least by me. I bought 4x8 1/2" mdo from them. Not cheap at $89 but they had it. Used it to build the sled holder that you posted plans and video on

jeffinsgf · « **Reply #10 on:** March 01, 2023, 07:39 AM »

Quote from: festal on March 01, 2023, 06:52 AM

@jeffinsgf lowe's actually has mdo at least by me. I bought 4x8 1/2" mdo from them. Not cheap at $89 but they had it. Used it to build the sled holder that you posted plans and video on

Weird...my local doesn't even show it as available for special order any more.

Jim_in_PA · « **Reply #11 on:** March 01, 2023, 09:32 AM »

MDO is not a typical product in the home centers because it's primary buyer is signmakers. A good sheet goods supplier can get it, however. That said, I would NOT use MDO for this application. It's exterior plywood and does not have constant thickness like MDF and may also have voids. There are also multiple kinds of MDO; some have a perfectly smooth surface and some telegraph the grain from the underlying exterior plywood core. There are also variations in the thickness of the paper surfaces, some is thin and some is more like 3/32"/1mm or greater MDF like product. MDF is a surprisingly durable material for these perforated surfaces and can last for years.

Cheese · « **Reply #12 on:** March 01, 2023, 09:51 AM »

I used baltic birch and can't complain, when I fab another I'll probably use BB again. The caveat here is I don't use this as a sawing table, just for hold down and glue-up.

@jeffinsgf that's an unfortunate Menards story...

...the local Menards here has 9 sheets of MDO in stock and will ship to the house for $22 or ship to the store for free.

Michael Kellough · « **Reply #13 on:** March 01, 2023, 10:10 AM »

I didn’t know there was that much variation in the quality of MDO. The stuff I’ve used has been very good. As flat overall as the very best plywood with a surface smoothness nearly equal to MDF but much more durable and moisture resistant.

But MDO is much harder to acquire than MDF. As long as MDF is kept dry it’s a fantastic material in terms of stability and economy. I’ve built machines with it using press fit bearings in place of aluminum plate and it worked fine. Better in fact since I could use glue and screws to assemble and reinforce.

Jim_in_PA · « **Reply #14 on:** March 01, 2023, 12:24 PM »

Michael, I've purchased MDO from Industrial Plywood out of Reading PA. They list more than one variation. The type I had was unpainted and had a thin paper-ish surface, but was void free and strong. It was good for painted projects, but the thin surface would not likely hold up to the constant abrasion from working on a table surface made from it in the same way it would hold up for road signs (a typical use). They also have some other plywood products intended for cabinetry work that have plywood cores and manufactured surfaces. It's neat stuff for the right application for sure!

jeffinsgf · « **Reply #15 on:** March 01, 2023, 02:18 PM »

Quote from: Jim_in_PA on March 01, 2023, 12:24 PM

.... It was good for painted projects, but the thin surface would not likely hold up to the constant abrasion from working on a table surface made from it in the same way it would hold up for road signs (a typical use). ...

Not my experience at all. The surface is holding up exceptionally well as a miter station and workbench top.

jeffinsgf · « **Reply #16 on:** March 01, 2023, 02:22 PM »

Quote from: Cheese on March 01, 2023, 09:51 AM

@jeffinsgf that's an unfortunate Menards story... ...the local Menards here has 9 sheets of MDO in stock and will ship to the house for $22 or ship to the store for free.

Wires crossed there. Festal and I were talking about Lowe's. His stocks it, mine used to offer it for special order, but I looked today and couldn't find it. Menard's here in Cleveland still stocks both 1/2 and 3/4 4x8s and will order 4x10s.

Crazyraceguy · « **Reply #17 on:** March 01, 2023, 05:10 PM »

My dog-hole top is MDF, drilled with the Parf-stick method. It has worked well for me, for the last 3 years.
I have yet to actually finish it....in both respects. I have plans to add a solid wood boarder around it to protect the edges. I have only gotten around to doing the front edge though, even it is not permanently attached yet. It's Dominoed in place and unglued. It is also un-sealed. I plan to do that fairly soon too.

The main piece of advice I would give to anyone planning to make their own top is to apply the finish before drilling/routing the holes. I wish I had thought to do that to mine.
I have always been careful/aware of water damage. Nothing like that gets near it.

Jim_in_PA · « **Reply #18 on:** March 01, 2023, 05:17 PM »

Quote from: jeffinsgf on March 01, 2023, 02:18 PM

Quote from: Jim_in_PA on March 01, 2023, 12:24 PM
.... It was good for painted projects, but the thin surface would not likely hold up to the constant abrasion from working on a table surface made from it in the same way it would hold up for road signs (a typical use). ...

Not my experience at all. The surface is holding up exceptionally well as a miter station and workbench top.

It really depends upon what kind of MDO you are using...there are multiple types.

Cheese · « **Reply #19 on:** March 01, 2023, 05:40 PM »

Quote from: Crazyraceguy on March 01, 2023, 05:10 PM

The main piece of advice I would give to anyone planning to make their own top is to apply the finish before drilling/routing the holes. I wish I had thought to do that to mine.

A big +1 on that...3 coats of clear on the bottom & 3 coats of clear on the top and THEN rout the dog holes.

squall_line · « **Reply #20 on:** March 01, 2023, 06:04 PM »

Quote from: jeffinsgf on March 01, 2023, 02:22 PM

Quote from: Cheese on March 01, 2023, 09:51 AM

@jeffinsgf that's an unfortunate Menards story... ...the local Menards here has 9 sheets of MDO in stock and will ship to the house for $22 or ship to the store for free.

Wires crossed there. Festal and I were talking about Lowe's. His stocks it, mine used to offer it for special order, but I looked today and couldn't find it. Menard's here in Cleveland still stocks both 1/2 and 3/4 4x8s and will order 4x10s.

That's how I interpreted it, but I can see how that could have gotten confusing.

I looked at MDO last time I went to Menards here. Or, at least, I tried to look at it. There were a bunch of people getting sheets of OSB and taking up space in the aisle, so I just kinda surfed on by. I'm thinking of making a laundry tower for our basement and figured that MDO was a decent starting point for that environment, all things considered (basement, laundry, sink).