box store mdf

[POPS 64]

I have some projects coming up and live in a pretty rural area. And only place within a 1 1/2hrs. is a box store . whats the disadvantage of this ? making signs indoor use that will be 2 and 3 level signs? Appreciate opinions.
Thanks jeff

[steve_g]

Jeff…
Big Box store MDF has a lower density and less resin than the “good” stuff. The problem is in the details! The lower density goods will flake apart when there are thin webs of material like in fancy frilly letters. If it’s all you have available, use bold text with no fancy extras! The cheaply made goods will also absorb moisture from the air faster and swell… cut soon after bringing it home and seal all sides…
SG

[scottp55]

Jeff, There is also a LARGE variation in the density within even inches. When I was driving those inserts my clutch settings were all over the place. I'll probably never buy it again. I think like Steve said you'll have problems with fine details. Kirk's 24X30" spoilboard drank a whole quart of some old Interlux Teak Oil and wanted more, but jury is still out if it will make more stable to humidity.

[POPS 64]

Thanks Steve , Scott , there are some lumber yards up here what do I look for to know I'am getting what I want . The place I get my specialty plywoods is 160 miles away so I try to time it while I'am down state visiting my kids . SO what do I need specifically . thanks guys

[t_vandemark]

Jeff, i've used the "cheap" stuff from the big box stores for the multi layered logos that i have done. Like the other guys have said, the fine details have a tendancy to break off or go all flakey. But if carefull it will work fine.

[Xray]

I've had fine results making signs with mdf, depends what you want to do. No problems with detail for shallow 2d cuts and I have made 100's of bases for LED signs with it, if you are making lots of cutouts you may run into problems. Helps to use fresh bits, mdf is rough on bits and when they start to dull they will tend to tear instead of cut, more so than in wood.
Cheap enough, it wouldn't hurt experimenting and see if it suits your needs.

[steve_g]

Jeff
What to look for,
My experience in Dallas Texas…
“Plum Creek Super Refined” is a brand of MDF designed to be made into moldings and consequently machines very nicely. 1/2” X4X8 $26.24 (8-5-14). 55 lb./ft3
“Medex” In my experience, holds the sharpest edge when v-carving, even though it has a lower density than the plumb creek. Must be higher resin content. ½” 4X8 $38.72 (8-5-14). 48 lb./ft3
“Exteria” Is a super high resin MDF not available in my area, Water proof and nasty dust when routing,
No name MDF is typically in the 41 lb./ft3 range it can swell 12% and still be in spec. $28.62 (HD 8-5-14)
I buy my Plum Creek and Medex from a builder supply, HD will order it in at greatly inflated prices!
SG

[scottp55]

Thanks Steve, Nice simple breakdown for hardwood guys who know nothing about this stuff.:)

[Chuck Keysor]

Steve, even though Scott already thanked you for providing great details on various types of MDF, I want to second his thanks for providing such an informative post!

I have been making some Victorian house carvings, and I will soon start to design three large relief carved exterior Victorian panels that go over the stairs on a fancy house here in Elgin. I had been expecting that I'd make these out of PVC, but I will now look into Extira as well. (That is a discussion for another thread, another day.....)

Thanks again, Chuck

[POPS 64]

Thanks Steve , see what I can find today going to check into that exteria there's a big call for outdoor V-carved signs living on a lake in a busy tourist town everybody wants to name there cottage. And I'am sick of cedar.
Thanks again Jeff

[GeneMpls]

I googled Plum Creek and Medex and here are the distributors

http://www.plumcreek.com/wood-products/medium-density-fiberboard/sales-distribution

Sorry.. lost the Medex link- But Metro Hardwoods in Mpls handles both
and they are about 15 minutes from me. Gene

[steve_g]

Addendum
I couldn’t find these images earlier… It clearly illustrates the problem with the big box MDF when V-carving.
This design from Briar Press (http://www.briarpress.org/ (http://www.briarpress.org/)) was carved in HD MDF, The tops of most all of the small background elements flaked off leaving “fuzzies” that were impossible to deal with. When carved from Medex, everything is crisp and clean (sorry no photo).
SG