MDO Edges

[Tonyfavs]

I am doing a MDO sign and in the past I have sealed the edges with bondo. I have been trying to get ideas and asking around and no one really seals the edges of MDO around here.

Any ideas on what is the best was to seal the edge of MDO?

thanks all

 

[StarSign]

We just paint them, never have any problems.

 

[J Hill Designs]

latex caulk, or wood glue

 

[tsgstl]

I rarely use MDO anymore. First I switched to Alumilite and now mostly Grimco's Max Metal or Proveers Tru Stock? But to answer your question I always just painted the edges. You can buy trim cap (plastic framing) but I actually think it traps more moisture speeding up delamination.

 

[Tonyfavs]

would love to not use MDO but the town requires wood. Lucky me.

 

[john1]

I've just painted them before with no problems that i have heard of anyway.

I have also used Elmer's wood filler, sanded it smooth then painted over it. Fills the voids and keeps moisture out good.

 

[Gino]

^^ ^^

After filling in with the Elmer's wood filler and sanding them, a good coat of prime would be beneficial before top coating.

 

[john1]

Oh yeah, don't forget the primer! I forgot about that, It's been a while since i have done a MDO sign.

 

[weaselboogie]

I recently made some Mdo signs with a non-exterior Mdo ( I thought all mdo was exterior, but apparently not. ) I primed and painted with latex and an automotive sprayer. Each side received 2 coats of prime and 3 coats of paint. Because I hit the edges at a 45 degree angle of spray, all edges received about 8-10 thin coats of paint. By no means was this a thick coating of paint. These were installed and I noticed a bit of a wave to these signs within 6 months. Within a year, one sign had completely delaminated through ALL layers of the board and was just a wobbly mess.

After talking with my plywood supplier, I found out that these were not an exterior glue. What still baffles me is that even with those 8-10 coats of paint on the edges, water was still able to penetrate through the edges. These were painted with Sherwin williams super paints. Needless to say after eating that job, I'm a bit gun-shy on using mdo without marine grade or a ridiculous amount of edge sealing.

 

[TwoNine]

Elmers Wood Glue (Or your favorite brand)

Then (if you want to go a bit further) place some plastic u-channel on the edges. Your supplier should have it in 8' lengths. Comes in 1/2" and 3/4".

 

[signguy 55]

Primer and paint always worked for me. I would take the extra step of hand sanding the primer coat and knock the sharp angle off the edges. If the paint is going to fail it's going to be there.

 

[AUTO-FX]

Ease the edges and then "paint" them with 2 part epoxy.( I've done this and learned it from friends who've been doing it at their shop for years and years.) Next day sand and paint.

 

[Fred Weiss]

I read years ago a tip sheet from one of the plywood manufacturers. They recommended the same sorts of filling as mentioned here already. But they also recommended spraying the edges with any standard aluminum metallic paint such as Krylon. Something about the aluminum flakes evidently works better. I have always used that technique and have never experienced an MDO failure.

 

[SD&F]

My two cents....I use wood glue and primer.

 

[ddarlak]

MDO is so 1980....

 

[TwoNine]

MDO is so 1980....

ANOTHER insightful post. Thank you DDarlak....Awesome input!!!

 

[Kottwitz-Graphics]

I also learned that if mdo is going to fail, it will be on the sharp edge, so I run a 1/8" round over on the edges, then fill with a (2) part wood putty (made by bondo, but made for wood). Sand smooth, prime, then paint.

 

[Malkin]

I also learned that if mdo is going to fail, it will be on the sharp edge, so I run a 1/8" round over on the edges, then fill with a (2) part wood putty (made by bondo, but made for wood). Sand smooth, prime, then paint.

We do this, and add some coats of Titebond III (mixed 50/50 with water) before the primer.
Also a coat of paint on the edges every time you paint a side.

 

[TammieH]

We use to use a brush/roll on Elastomeric Paint (water sealer) on the edges works well
But nothing lasts

 

[Jillbeans]

Two coats of Titebond2 wood glue, then two coats of Kilz primer, then whatever I'm coating out the rest of the panel with.
I try to avoid using MDO.
Love....Jill