Mdf

[Jack Frederick]

I have not worked with a great deal of mdf. I was looking over Alan’s post on dog hole spacing and the Parf guide and had been thinking that a station for my TS55 track saw would be a good add to the shop. Is all MDF created equal? Is there a preferred spec for a MFT top? I spent about 45 minutes on the Tube yesterday on the Parf guide and one is now on the way to me, so this is happening.

[Mark Bolton]

Your best bet for a decent solid MDF top will be to source double refined or some suppliers call it door grade. All MDF is not created equal. The standard material you will find at retail suppliers is medium density (M-D in MDF) but there is low density, ultra low density, double refined, and then exterior grade material. The double refined will be much heavier, far denser, and have a harder/smoother face and core. The stuff thats often at the home centers in my opinion is the ultra lowest end of "medium" that we get from commercial suppliers. Door grade/double refined machines and finishes much nicer and will be far more durable for things like dog holes/clamp holes in a multi function table.

[Jim Becker]

I agree with Mark...useful material for sure, but absolutely are different quality products out there.

I've taken a shine to the "exterior" versions for utility use having benefited from using leftover material from client projects for things like worksurfaces. The greater density that Mark mentions is one reason and the increased water/moisture resistance brings more peace of mine relative to a work surface. That said, even the cheap stuff works very well for work surfaces as it still is generally consistent in thickness and more durable than many folks think.

Be sure to use PPE and the best dust collection you can manage when working with MDF...it creates an exceptionally fine dust as a byproduct of cutting/machining. Sealing the edges is a good idea for long term moisture control, too.

[Frank Pratt]

I too have switched to the water resistant MDF. Medex is the brand that the local suppliers carry. It looks like big box MDF, but that's where the similarity ends. It's much harder, stronger and doesn't delaminate nearly as bad. And it doesn't swell & turn to pulp at the first hint of moisture. It is not waterproof though. I left a piece submerged for a couple of days & it did swell up about 10%, though it didn't turn mushy at all.

[Keegan Shields]

I have a similar work surface and use the 3/4” MDF from HD. Before drilling the Parf guide holes, I thin some old oil based poly with mineral spirits (1:1) then put on 2 coats. Seals the MDF right up and increases durability. Got that tip from a Mike Farrington video on YouTube.

[Mark Bolton]

If you sourced double refined you'd have probably paid $10 more per sheet and saved hours of your time that could have been invested in fruitful shop work instead of mediocrely improving a crappy product burning up hours of your time. Whats your day job pay you per hour? Your personal time must.be worth at least half that? $10 a sheet extra to allow more time in your hobby or with your wife and kids is cheap money. Fareington is there to profit from your eyeball time. Think for yourself.

[Edwin Santos]

I see you're located in N. California. It's very possible the highly refined, high density mdf in your area is under the brand Plum Creek, especially if you're buying from Peterman Lumber.

To echo what others have said, it is worth the additional cost per sheet. Mind you, prices are very disrupted right now, so lord knows what it is running. In the past my experience was the same as what Mark B. has said, about $10 more per sheet.
Among the benefits is that it machines very well. I have achieved excellent routed surfaces that did not require coming back with bondo, multiple coats of BIN, drywall mud, or whatever methods for sealing the surface so it will take paint well.
Holds fasteners quite well too.
Downside? Heavy

[Richard Coers]

There are 3 types of MDF, Lightweight, Standard, and High Density. If you have a Industrial plywood distributor remotely close, buy there instead of big box. I doubt if the supply issues have eased, but I guess you will only be buying 1 sheet. Probably hard to get a big supplier to sell 1 sheet.

[Keegan Shields]

If you sourced double refined you'd have probably paid $10 more per sheet and saved hours of your time that could have been invested in fruitful shop work instead of mediocrely improving a crappy product burning up hours of your time. Whats your day job pay you per hour? Your personal time must.be worth at least half that? $10 a sheet extra to allow more time in your hobby or with your wife and kids is cheap money. Fareington is there to profit from your eyeball time. Think for yourself.

Chill out friend. You know what they say about assumptions.

I use HD 3/4” MDF for a work surface because it’s cheap, I get an extra veteran discount, and it’s 1 minute from my house. My lumber supplier is a 40min drive away and they aren’t open on weekends.

The cheap MDF has never failed me as a work surface and it easily replaceable. It’s ok if you like something different.

[Erik Loza]

Maybe not what you were asking about but Tricoya MDF is REALLY hard and totally moisture-proof. I imagine the glues they use make it so dense. If there were a local source, it would be my first choice for a work table top. OP, it looks like they have a couple of NorCal dealers: https://royalplywood.com/

Erik

[Alan Lightstone]

Maybe not what you were asking about but Tricoya MDF is REALLY hard and totally moisture-proof. I imagine the glues they use make it so dense. If there were a local source, it would be my first choice for a work table top. OP, it looks like they have a couple of NorCal dealers: https://royalplywood.com/

Erik

Is it brutal on bits and blades?

[Erik Loza]

Is it brutal on bits and blades?

Mmm…. “Probably”. We only experimented with it, no major projects. I imagine most customers would machine it on a CNC router but my thought is that MDF is already not that kind to tooling, anyhow, and this would be a little worse but not much firsthand experience. But, if the project would really benefit from it, none of this would stop me. What this stuff offers, no other MDF can touch.

Erik

[Ron Selzer]

Is it brutal on bits and blades?

Have not worked with mdf since the 80's, so take this for what it is worth
We used to get lifts of imported mdf in due to lower cost and the tooling wear was over double that of USA made mdf.
finally convinced powers that be to go back to USA made
Usa made was a light brown and the imported stuff was darker. Could tell a big difference in the saw dust also.
Headed in a different direction work wise and never had to deal with imported mdf again
Good luck
Ron

[Brian W Evans]

Chill out friend. You know what they say about assumptions.

I use HD 3/4” MDF for a work surface because it’s cheap, I get an extra veteran discount, and it’s 1 minute from my house. My lumber supplier is a 40min drive away and they aren’t open on weekends.

The cheap MDF has never failed me as a work surface and it easily replaceable. It’s ok if you like something different.

Agreed on all counts. The time required for me to source other material and drive the 45 - 60 minutes each way on a weekday makes putting on a few of coats of poly the better solution. I made a regular MDF top for my SCMS station and my assembly bench. Both have several coats of wipe-on poly and are very hard and smooth. It only took a couple of minutes to put the poly on, then come back the next day and do it again. For me, this was the least expensive and most efficient route.

[Jack Frederick]

Thanks everyone fro the information on this category. Erik, your lead on Royal is appreciated. I submitted a request for pricing on a couple sheets of 4x8x3/4 Medex and Trifoya, but have not heard back. I’ll give them a call in the am. They are located about 90 min from me. My local building supply yards basically have nothing but odds and end sheets and you know what the bottom of a pallet of this stuff ends up looking like. So, I think I will make a run to the Depot for a piece. As it is the first of these I will be cutting it is probably for the best that I check out the competitive product first. I can co-ordinate a trip to Royal and Woodcraft at some point. I’ve spoken with a couple local friends who are interested and with the Parf Guide we can make them. Again, much obliged for the leads.

[andrew whicker]

I can't buy sheets of MDF right now (Utah) because I'm not a big enough buyer... I think I MAY be able to buy 3/4, but I can't get 1/2 to save my life. Otherwise, I'm relegated to HD or Lowes.

So anyway, for all those telling you to buy some at the pro shops... ha.

[Bob Jones 5443]

MDF is such a useful material for jigs and sturdy backing tasks. When I was in a professional's shop in England a couple of years ago, I saw him using green MDF that was exceptionally sturdy and dense. It machined like butter. No idea where he sourced it –– didn't think to ask. It might not be available in the US, but if I could find a sheet each of 1/4" and 3/4" I'd jump on it.

[Rick Potter]

Just a suggestion about blades.

When I cut MDF or Melamine particle board, I usually change blades to a 7 1/4" circ saw blade. Dirt cheap, and easy to find. Very thin kerf too. I hate to dull a $100 blade on that stuff.

[Rich Engelhardt]

Just a suggestion about blades.

When I cut MDF or Melamine particle board, I usually change blades to a 7 1/4" circ saw blade. Dirt cheap, and easy to find. Very thin kerf too. I hate to dull a $100 blade on that stuff.(As I smack my forehead and exclaim!>!>!>!)THAT is so simple....why did that never occur to me!


Thank you
That tip alone is worth every penny of the $6 yearly subscription to here!

Thank you -Thank you -Thank you (as Gomer Pyle would say!)

[Jack Frederick]

Looks like the standard available HD 3/4” MDF is the right tool for the job. I just got a price on the Medex from Royal and it is $327 per sheet. I have a good sense of humor, but yikes!

[jack duren]

I never noticed the difference, but after 40 hours I send the blades of to be sharpened..

[Frank Pratt]

Just a suggestion about blades.

When I cut MDF or Melamine particle board, I usually change blades to a 7 1/4" circ saw blade. Dirt cheap, and easy to find. Very thin kerf too. I hate to dull a $100 blade on that stuff.

Honestly, I don't really notice that carbide blades dull much faster with MDF. I realize they do, but it's not enough for me to go through the hassle of changing out the blade. Steel jointer & planer knives are quite another thing though. MDF will dull them pretty quickly. My son unknowingly edge jointed a bunch of MDF pieces & the knives were noticeably dulled where it ran across them.

[Rick Potter]

In my case I use the Melamine particle board much more often than MDF. Agreed MDF is soft, but don't forget the old adage about dulling a knife cutting paper.

Melamine particle board now, is another matter. I have seen sparks come off the blade cutting that. They used to make some that had much more glue, and was more dense. Forget what it was called, but that was like cutting rocks.