Medex

[steve_g]

I was looking for an exterior MDF type product to use for a sign. (My customer didn't want to spend the money for foam...) I was looking for a product called "Exteria" as I was told that this was exactly what I needed. I could not find any locally but my regular supplier suggested "Medex" http://www.plywoodcompany.com/application/home/itemdetails.aspx?categoryid=92&itemid=320 (http://www.plywoodcompany.com/application/home/itemdetails.aspx?categoryid=92&itemid=320)

My first impression is... WOW!!! It holds V carved edges better than even the "good" MDF. and when cutting, the waste comes off as chips instead of a toxic cloud. Cost wise it was only $10.00 a sheet more than the "Plum Creek" super-refined I'd been using. On top of all this goodness, it's supposedly an exterior material... Here's where I'm skeptical...Does anyone have long term experience with this material?

Thanks!

SG

[Brady Watson]

Yes. Great stuff for exterior applications. Many have coated it in epoxy as an added coat of protection before hitting it with automotive paint.

Just a word to the wise...don't be fooled. That stuff is very toxic and will jack up your sinuses and lungs in short order, so keep that in mind.

It does machine pretty well. Years ago Bill Palumbo machined a 3D alligator out of the stuff that was something around 9 feet long for the Extira company (http://www.extira.com/). You can see some pics of the project here (http://www.talkshopbot.com/forum/showthread.php?t=4761&page=3). From what I remember, it was wicked heavy...

I left a few 4" x 4' strips in the back of my truck thru rain, heat, snow etc, and although it did gray a bit, there were no signs of delamination or structural degradation after about a year.

-B

[Rick W]

Steve,

I don't have any experience with that material, but I really like your sign.

Good job!!!

Rik

[bob_reda]

I used the 3/4 " stuff to make some 30" tall letters for a friend when Ford took away his franchise and he became a used car salesman. Had to change the name of the company. With a good primer and topcoat, they have been up in the weather here in Pa for about 7 years and look like the day they put them up. As Brady says, very toxic, wear a mask, even with dust collection.

Bob

[bleeth]

Steve:
In case you didn't pick up on it Brady was talking about Extira.
Medex, made by Sierra Pine, is specified for high moisture areas but is not specifically recommended for exterior use as siding or trim.
Here is a link to the manufacturer's site:

http://www.sierrapine.com/index.php?pid=68

I would not guarantee your sign beyond Sierra's specs, although when properly coated on all sides it should last well. Check out the finishing guidelines link at the bottom of their page and it actually focuses on usage for signs.

Dave

[steve_g]

Thanks to all for your insight and comments about this "new to me" material. I have to tell a story on me... I carried a single sheet home to try in my Ford Ranger pickup. If you have ever had a small truck, you know that the way you carry a full sheet is on top of the wheel wells and out over the top of the tail gate. When I took off at a light at a very busy Dallas rush hour intersection, the very slick sheet of Medex popped out of the truck and was run over by several hundred vehicles before I was able to retrieve it. The fact that I was unable to find any damage to the sheet was the first thing that impressed me!

SG

[pappybaynes]

Extira should be washed with soap and water to allow the finish to stick...and it is worth repeating what Brady said - the dust is toxic.

[rb99]

Is signfoam hdu dust less toxic?

[Brady Watson]

Steve:
In case you didn't pick up on it Brady was talking about Extira.
Medex, made by Sierra Pine, is specified for high moisture areas but is not specifically recommended for exterior use as siding or trim.


Thanks for clarifying, Dave.

Medex is the best spoilboard or vac plenum material in my experience. It is uber stable and cuts really nicely. It seems to handle fluctuations in humidity very well. I would not use it outside...If you had a call for that sort of thing, use the Extira.

There are some who have made signs out of Medex, but they 'plasticized' the material using first a few coats of shellac (thin, penetrates well) and then a couple coats of epoxy (like West System) before top coating with automotive primer.

-B

[steve_g]

Some of the responses have scared me regarding toxicity... I was able to get a Medex MSDS but Exteria safety data sheets are only available from the distributors... Sounds like Exteria isn't bragging about its safety! The Medex appears to be no more toxic than wood.
http://www.plywoodcompany.com/application/__content_files/Item/06172/MSDS-SierraPine-MDF-NAF.pdf (http://www.plywoodcompany.com/application/__content_files/Item/06172/MSDS-SierraPine-MDF-NAF.pdf)

SG

[mark_stief]

Steve I've cut between 25 or 30 sheets of Exteria over the past couple of years and have had no problems with the dust just let your dust collector do it's job your making a sign out of it your not shredding it into little pieces there won't be that much dust if your worried wear a mask Just my 2 cents P.S. It makes really nice signs I made the town one out of it been there four years outside still looks new

[steve_g]

Richard

Is signfoam hdu dust less toxic?

I had hoped that someone with more firsthand knowledge would answer this... My experience is limited but the MSDS seems to back up my impression... it's an irritant but not considered toxic.
http://www.dunagroup.com/dati/pdf/msds-duna-usa-corafoam-pur-foam-rev_1.pdf (http://www.dunagroup.com/dati/pdf/msds-duna-usa-corafoam-pur-foam-rev_1.pdf)

SG

[billp]

"Toxic" has multiple levels of danger. You have products which are composed of various chemicals, and compounds that are NOT conducive to promoting good health. Some of these ingredients taken on their own would probably be declared as "poisons" but due to their lesser concentration in these products they "pass" whatever levels of 'safety' their respective industries have 'bought" through lobbyists, and purchased legislation.
THEN you have the semantics of what IS "toxic", and where along the line does a substance become dangerous to our health. Something that is not poisonous can be just as deadly in specific forms of it's production. Just about ANY material that does NOT degrade quickly,or can NOT be readily absorbed by the body is JUST as dangerous as the poisons. Labeling something as "safe" just means that it has been "approved" by some of the above regulatory bodies whose members rarely spend long hours exposed to having their bodies/lungs try to "filter" them through one's system. There's a reason that one of the earlier names for Silicosis was "Potter's rot"...
A good example here is the perception that "organic"ALWAYS means safe, when in reality it's meaning is that it is a naturally occurring product, and not manufactured by man. If you thought that ALL "organic"products were "safe" consider the history of THESE two naturally occurring materials, and consider that they have both probably done more TO mankind, than FOR us; coal dust, and asbestos...
There are very few materials that you really want to breathe when they have been pulverized into such fine particulate matter, so if you are truly concerned about YOUR health, and those who are in your shop, WEAR GOOD PROTECTION ! NOT a cheesy piece of cardboard that usually can't create a complete seal around your mouth/nose. Many good respirators supply you with a 'test"ampule of some liquid you are to use after your mask is in place. it is typically "flavored" (banana, etc.) so you will recognize the aroma, and if you CAN smell it when you have the mask in place then you are NOT fully protected.
It's ironic how many people are fastidious about the way their tools are kept, and they use filters and the like ( ie. the "dirt bag") on their computers, but then they will spend 8 hours in a contained space breathing MDF dust as though it's not an issue.....It IS.....

[Brady Watson]

Steve I've cut between 25 or 30 sheets of Exteria over the past couple of years and have had no problems with the dust just let your dust collector do it's job your making a sign out of it your not shredding it into little pieces there won't be that much dust if your worried wear a mask Just my 2 cents P.S. It makes really nice signs I made the town one out of it been there four years outside still looks new

Mark - One of the indications that you've been affected, is partial or complete loss of punctuation. :D

-B

[kurt_rose]

!!!!??????,,,,,,........... Healthy as a horse!:D

[steve_g]

!!!!??????,,,,,,........... Healthy as a horse!


Thank you Kurt... you made me smile!:)

SG

[mark_stief]

Brady
I've been told all my life I'm not "NORMAL":eek: must have something to do with my third arm it's always getting in the way of my other two or it's the hillbilly thing
Plus my teachers in school always said I was a hopeless cause if they could only see me now:D Hmmmm maybe the wood dust is starting to affect me:p

[bleeth]

Have you ever seen a guy with a beard wearing a respirator? In the shipyard they used to make those guys spread vasoline on their beard to get a seal. Of course, Vasoline transmits chemicals and you can't smell anything but it!!

Pure water is not dangerous to your health-Just ask the CIA!!