External House Shutters using MEDEX (external MDF)

[Nate Secrist]

Hi,

I am going to build some external shutters for my house. I am going to build them raised panel style - like the picture below.



According to the MEDEX data sheet - it looks like it would work fine for these shutters.
http://www.sierrapine.com/media/modu...Spec_Sheet.pdf


I will prime and paint the shutters, so it won't be raw wood exposed to the elements.

My question is more around how the finish will look when using the raised panel cutters.
For normal, interior MDF, the faces paint up very nicely, but the edges don't take paint very well, unless you seal them with a glue/water mix.

If anyone has worked with MEDEX - a couple questions

1 - Will it dull the raised panel cutters?

2 - How about painting the raised panels? Does the edge grain need to be sealed first with glue/water to get a nice painted edge?

3 - Comparison of MEDEX vs EXTIRA. I found a local supplier for MEDEX - about $68 for a 4x8 sheet
Another supplier has EXTIRA - but it is about $100 per sheet


Any opinions (Good or Bad) of MEDEX would be appreciated!

Thanks Alot

[Erik Loza]

Well, there's exterior and then there's EXTERIOR. Your shutters will honestly never see rain or direct water contact? No personal experience except to say that when I hear "MDF" and "exterior" in the same sentence, well.... Yeah, it probably will dull your cutters.

Curious to hear if anyone has any feedback and best of luck with the project.

Erik

[Mel Fulks]

Haven't used medex but use EXTERA and like it. Mdf will dull steel cutters ,but carbide is fine. Makes a lot of dust, protect
your lungs. I sand the raise just enough and use the acrylic primer to fill them and de fuzz. I find the EXTERA to be excellent in outside vertical Aplications. Just made some cornice end caps (or contour boards) for my house .SO much better than plywood full of football patches.

[Peter Quinn]

I used a bead board product made of medex, was for a powder room/mud room install, wanted better performance behind the toiled/ pedestal sink than regular mdf. I started the job by cutting a few ends off and throwing them outside in November in a 5 gal bucket of water where they sat for weeks, froze a bit, thawed. I pulled them out a few weeks later, was amazed they hadn't swelled and didn't seem affected at all by the water. Later the boy living in the house pulled the pedestal sink trap out of the wall by using it as a jungle gym, was doing it when I got there for the call back "there's water on my floor and wall...." I called the father in.....after driving 45 minutes for this emergency....and asked "does he do this regularly?" The whole wall was flexing....I reinstalled the trap and drain, there were stains on the wall from the mini flood as they had been using the sink with drain pulled out. The medex was again unaffected by the experience, regular mdf would have been shot.

will it dull tools? Yes, definetly, the dust is green like pressure treat, it's even more noxious than regular mdf, don't know if it dulls more but at least as bad. Finishes about the same as regular mdf, you need to multi prime and sand the molded areas prior to assembly. This is not bad for panels but sucks for cope and stick.

[John Lanciani]

I've had MiraTEC http://www.miratectrim.com/ trim on the outside of my house for about 10 years now. I didn't really believe it at first but I have no doubt now that with the correct materials and good installation MDF can hold up perfectly well outdoors.

[Bradley Gray]

If I were making this style of shutter from a composite, I would skip the joinery and make 1 piece shutters, route out the panel fielding and square the corners with a chisel.

[Jeff Ramsey]

Personally, I loathe milling MDF. You'll need 100% dust collection efficiency, or the area around (and possibly your entire shop) will be covered in dust. Remember, Medex is water resistant, not water proof. If you're averse to using vinyl, and your house has existing wooden shutters why not just use wood? You'll still have to repaint the Medex now and then, just like wooden shutters. BTW, I'm replacing two of the remaining six wooden shutters on our house with vinyl when they come in (they're ordered). They're more durable, and I don't have to paint them over and over. It's bad enough I have to continually fill downy woodpecker holes in the cedar siding; I am tired of painting wooden shutters.

[Martin Wasner]

Look into making them out Richlite. Should last an eternity.

http://www.richlite.com

[Sam Murdoch]

If I were making this style of shutter from a composite, I would skip the joinery and make 1 piece shutters, route out the panel fielding and square the corners with a chisel.

This is a good idea +1. As for Medex - it is a fine product for this application as some of the real world test described above affirm - though on the heavy side.
The hips do need to be primed and sanded again before final finish - thinned glue not really needed just a few coats of good sandable sealer that is compatible with your top coat.
On interior panels I have skimm coated with drywall mud - very light coat to fill in the pores, sand and prime but 2 coats of primer with sanding between coats worked just as well.

[Mike Heidrick]

BIN sealer at Lowes works good to seal MDF. Ive not used it in an exterior application though.

Why risk it though with any MDF variant? Why not a wood rated for outdoor use?

[Nate Secrist]

Thanks everyone for the feedback on MEDEX/Exterior MDF materials.

When I originally posted, I was only thinking about using MEDEX for the actual raised panel part of the shutter. I was planning on using real wood for the stiles & rails.
A couple posts got me thinking, so now I have 3 options: (I know I can always use real wood for all the parts - I have done this multiple times)

I was thinking about a few different ways to do this. Please chime in with your thoughts on these options:

OPTION 1 - Use real wood for stiles and rails and use MEDEX for the panels

OPTION 2 - Use MEDEX for stiles & rails AND for the panels. I would still cut out and rout all the pieces like normal. i.e. cope cuts for the end-grain, stick-cuts for the long-grain,
Panel Raising bit for the profile on the panels.
Do you use a regular exterior wood glue (like Titebond III) to glue up all the parts?
The downside is the nasty dust and the dulling of cutters and blades. Upside would be that it would be easy to cut all the parts from a sheet of MEDEX - no need to joint, plane and prepare the rough lumber for the stiles & rails.


OPTION 3 - Use a solid MEDEX panel for the whole shutter. This is where I am in uncharted territory........
Can this be done without some kind of CNC setup? Or can this be done on a normal router table?
Seems like the panel would need to be stationary and the router bit would need to be in some kind of overarm router.....
I am not able to envision this with a regular router table setup?
If this is possible to do - can someone explain the process for this? Or point me to someone's personal website with pictures?

Please let me know your thoughts - I am always excited to learn a new way to do different projects.

Thanks Alot - I always learn a ton from you guys!

Nate

[Mel Fulks]

The EXTRA dust with option 2 would not amount to much more than option 1. 3 will work if you can accept a flat panel raise rather than a sloped one. Any exterior wood glue will work.

[Bradley Gray]

OPTION 3 - Use a solid MEDEX panel for the whole shutter.

If you have a plunge router this can be done with a simple frame that surrounds the router base. Add 2 times the distance from edge of bit to edge of router base to the panel dimension. Add some strips to the back of the frame to locate it on the shutter, clamp to a bench and route. Don't forget your dust mask!

[Jim Matthews]

Is the shutter functional, or purely decorative?

[Mike Heidrick]

I don't honestly think I have ever seen a functional shutter on a house in person.