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MDO or ACM? When to use what?

Texas_Signmaker

Very Active Signmaker
I have a customer requesting a bid on a 5'x24' sign on a corrugated metal building, one smaller one for a chain link fence and another smaller one for the metal wall as well. They ordered signs from another company that printed them and after 2-3 years they are turning brown/black. They contacted another sign company outside of our area and they were trying to talk him into "premium 3M" vinyl on MDO. It's a mostly one color sign on white background so no issues using cut vinyl.

This other sign company out of town suggested MDO which I really didn't agree with. The previous sign company that made the signs in the first place used corrugated Alumalite which I thought was overkill for the walls. I've steered away from Alumalite because it's expensive, dents easy and I don't really like they way it's painted.

My default for most sign boards are 3mm ACM if it's against something or 6mm if it's not. What would you guys use? Would you use MDO or Alumalite? Am I suggesting the wrong thing to them?

Also, I checked the lifespan of 3M cast and it's 7 years, Oracal 651 is 6 years.. so would you suggest the 3M cast for that additional year or would it vastly outlast the 651?
 

SignosaurusRex

Active Member
Do yourself and the customer a favor here... stick to ACM with "Cast" vinyl. If material cost(s) are of deep concern, It is your job to educate your customer on the advantages of a better product and charge them accordingly. I think the previous sign supplier already made your job easier in that endeavor. MDO is a mere shadow of what it once was in years past. MDO is best left for short-term construction notice boards. "Alumalite" is nothing more than a glorified Corex with a minimal skin of Aluminum...again a poor choice for extended life and quality. As you know... Oracal 651 is not a "cast" vinyl and should never be considered for use on long-term signage. The individual life-span ratings of various vinyls are based on "optimal" conditions and are greatly effected by various elements of "directional exposure" whether it be Northern, Southern, Vertical, Horizontal etc, as well as climate.
 

Texas_Signmaker

Very Active Signmaker
I just don't get the Alumalite thing. It's twice as expensive and doesn't seem as good yet alot of sign companies sell it.
 

visual800

Active Member
I still prefer aluminum sheeting and my vinyl is 751. 040 aluminum will suit you well for this job. I dont get the whole MDO thing any longer, too much prep and it simply is not lasting. aluminum come in 5' sheets so a 10' would suit you for this job
 

Johnny Best

Active Member
MDO is not good anymore, for years that is all I used. But edge prep is a lot of work, it delaminates quickly and breaks down with moisture and time. Not even worth buying for exterior work.
Years ago it had like 4 layers, now it looks like 10 layers. Better machines to get that paper thin cutting to get more off the offshore newgrowth trees.
It's ACM with cast vinyl for a better longer lasting sign product.
 

Texas_Signmaker

Very Active Signmaker
I still prefer aluminum sheeting and my vinyl is 751. 040 aluminum will suit you well for this job. I dont get the whole MDO thing any longer, too much prep and it simply is not lasting. aluminum come in 5' sheets so a 10' would suit you for this job

The thing I don't like about 040 is that it doesn't appear "flat" when installed on Dryvit or corrugated metal
 

DerbyCitySignGuy

New Member
MDO is not good anymore, for years that is all I used. But edge prep is a lot of work, it delaminates quickly and breaks down with moisture and time. Not even worth buying for exterior work.
Years ago it had like 4 layers, now it looks like 10 layers. Better machines to get that paper thin cutting to get more off the offshore newgrowth trees.
It's ACM with cast vinyl for a better longer lasting sign product.

Agreed. It's not just MDO either, all lumber has gone down in quality over the last 20 years. It's a crap shoot as to how many bananas you're going to get when you order a lumber package.
 

JTBoh

I sell signage and signage accessories.
I still prefer aluminum sheeting and my vinyl is 751. 040 aluminum will suit you well for this job. I dont get the whole MDO thing any longer, too much prep and it simply is not lasting. aluminum come in 5' sheets so a 10' would suit you for this job

0.040" bolted tight on a metal building will buckle in different directions - light will hit it differently and make it look worse.
ACM doesn't have that problem, and is the right material for the job. Now you just gotta sell it. Say stuff like "I don't know why they would recommend that product" and "ACM has replaced these products in recent years - some people don't like the future, I guess (reckon in TX)"
 

Texas_Signmaker

Very Active Signmaker
0.040" bolted tight on a metal building will buckle in different directions - light will hit it differently and make it look worse.
ACM doesn't have that problem, and is the right material for the job. Now you just gotta sell it. Say stuff like "I don't know why they would recommend that product" and "ACM has replaced these products in recent years - some people don't like the future, I guess (reckon in TX)"

That's exactly what I said. I've been in the sign business now for 13 years and never saw reason to use MDO. Just thought I was missing something because people are still using / requesting it. I RARELY use anything other then ACM. Is there a situation NOT to use ACM?
 

Texas_Signmaker

Very Active Signmaker
Be it me to question the status quo.. But if 651 is 6 year and 7125 is 7 year does it justify $100 vs $400 for a roll? Now, I know the arguments that $400 for a roll is not that much $$ per sign and I get that. I know cast is great for curved surfaces. But is there something I'm missing when they say 6 year vs 7 year? Does 7125 last much longer then the stated 7 year? I've now been around long enough to see some of my first signs start to need replacing and that I've used 651 and noticed they start to look shabby after year 8-10... but it's not just the vinyl, the entire sign usually looks like it needs a paint refresh and substrate looks dirty.

Main difference I see with the cast when talking about longevity is that up-close it doesn't shrink like calendared does which is why I use it on vehicles but generally not signs that are high up.

The main argument has been "it's not that much more $$ for cast per sign". I get it, but if your buying something for $100 and they said "it will last 6 years but for $400 you can get one for 7 years" I would think most people would say nay nay.
 

JTBoh

I sell signage and signage accessories.
Yea, its up to you to tell the customer that MDO is outdated. They've probably been in business for 20 years and they probably still think that MDO is the way to go, because no one has taught them otherwise. Youve been doing it a long time, and "youre the expert" - most customers can be lead around when you say you're right.

At ~6x multiplier (cost vs. customer price) for cut vinyl, $300 gets eaten up damm quick, and gives the best quality product. Sign companies have a HUGE profit margin on cut vinyl. You can say we only use the best, and that is a selling point. Cal is a lot more susceptible to failure in many different ways - even though it likely won't, its just another layer of protection for customer retention. Realistically, cal is gonna fail eventually - but I've seen cast last a lot longer than 8 years.
 

Texas_Signmaker

Very Active Signmaker
Yea, its up to you to tell the customer that MDO is outdated. They've probably been in business for 20 years and they probably still think that MDO is the way to go, because no one has taught them otherwise. Youve been doing it a long time, and "youre the expert" - most customers can be lead around when you say you're right.

At ~6x multiplier (cost vs. customer price) for cut vinyl, $300 gets eaten up damm quick, and gives the best quality product. Sign companies have a HUGE profit margin on cut vinyl. You can say we only use the best, and that is a selling point. Cal is a lot more susceptible to failure in many different ways - even though it likely won't, its just another layer of protection for customer retention. Realistically, cal is gonna fail eventually - but I've seen cast last a lot longer than 8 years.

Gotcha. I just would like to give them a better argument (and frankly for myself to know) then "it's the best". Like I said, the argument about how much it's costing per sign vs what we're getting is something I always hear but I can't use that argument with the customer!! lol
 

Bigdawg

Just Me
I use Oracal 651 and 751 vinyl pretty exclusively unless forced to go to another brand because of color matching. The 651 actually does hold up pretty well here in the Florida sun - I expect our sunny conditions are similar to yours. I generally use 751 on all outdoor signage unless it is temporary. The big thing (as you mentioned) is the shrinkage with 651. The other is some colors (I'm looking at you red and blue vinyl) tend to deteriorate at a much faster rate than the blacks or whites do. I have signs that I did in black 651 10 years ago that still look pretty darn good. But that tends to be the exception and not the rule. I highly recommend 751 because of the longevity. We realistically rate the 651 at 3 yrs max "still looks good" and not the manufacturers' rating of 5 years. With the 751 we are getting twice that time plus.
 

Gino

Premium Subscriber
We still use a fair amount of MDO or what was originally known as Duraply.

It all depends what you buy as to the quality of the product. Buying Guardian or Signal or even some other brand as long as it has good components will do just fine.

Our MDO board is 5 plies, with a thermosetting resin-impregnated fiber surface bonded to one or two sides under heat and pressure. Selected veneer directly beneath the fiber overlay creates the nice surface for painting. This veneer is what prevents footballs [patches] from telegraphing through. An outer layer of paper overlay finishes the board so all you hafta do is prep it and paint it properly.

While the product is just slightly less (in cost) than 6mil Alumalite, it is a far better product, if treated properly.

The problem is, most sign people are lazy today and do not want to put the time, effort or money into using this product. Once you have it.... with prep, priming and painting..... you'll have more time invested, which results in a more expensive product, not to mention a much heavier product to lug around. Suffice it to say, it's far easier to buy a piece of ACM and not hafta do a thing except letter it or wrap it, plus now one person can put it on the side of a building on a ladder.

I will say, all the ACM boards we get, regardless of their cost tend to chalk out way faster than the painted MDO boards.
 
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Baz

New Member
I hav e been using ACM over MDO for a while now.
It is nice to not have to do any prep work and go straight to lettering/wrapping the board.

But personnaly, i do prefer MDO. It adds allot of structural strenght once you screw it to a wood frame.
Your screws end up flush to the surface instead of the screws heads sticking out of the sign.

I am set up to prep MDO pretty easily but having to compete with other shops who have flatbed printers.
I have to quote using ACM.
 

RyanT

Director of Entropy
I like MDO when structure is required, visible edges need to look good, or when signs will be abused. In areas around here, sign posts don't go very deep so can't be counted on to stay solid and ACM isn't very sturdy. MDO and posts makes for a solid assembly even in thin soil.

I also have a customer with event signs that go up and down twice a year, handled by volunteers... they get beat up. MDO is the ticket there, although I guess I could have sold them new ACM signs every year. But I don't operate that way.

ACM is probably fine. I have a long term test going on with oracal 651/751/951 on MDO on the roof of my shed right now, south facing. Two years in and no difference yet. Will report back in 5 years.
 

Sandman

New Member
Many comments about the poor quality of today's MDO, no mention about how poor today's alkyd enamel paint (aka One Shot) is as well.
Anyway, I find MDO (not even considering the poor quality) over priced and labor intensive.
MDO requires sanding the face, sanding the edges, rounding the edges, filling the edge voids, sealing the edges, then priming and painting to get close to 10 years life. (If you can find decent paint) Cost of MDO not including labor and paint...$497.68 with a 3' x 4' piece left over.
ACM, if white, cost of material for a 10 year life with a 3' x 4' piece left over... $323.57 and ready to letter with 3M cut vinyl.
ACM in colors, $487.80 in cost, 8 to 10 year life, six 3' x 4' pieces left over (my supplier only carries 4x8 in colors so disadvantage of having to install 6 panels on the wall instead of 3)
Above costs are for a 24' x 5' sign. So add another $100 to $150 in labor and paint for MDO and ACM proves to be much cheaper. More than makes up for cast vinyl over calendared. My 3M cast vinyl always lasts at least 10 years.
 
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