Adams vs. Ross

Ladies and Gentlemen. Are you ready to RUMBLE?

Welcome to the Ringside Arena in the Metro FliteTest Center to witness the greatest and most anticipated bout ever conceived for scratch builders.

In the blue corner, the undisputed world champion who needs no introduction... Costing $1 per sheet, weighing in at 114 grams, used as the most common building material for FliteTest models and has a proven history of being a lightweight, inexpensive building material and distributed by Dollar Tree, a big welcome back to the one, the only - Adams Readi-Board foam core (applause).

In the red corner - the challenger, a newbie on modeling circuit that hasn’t seen as much attention but has significant momentum with a straight winning record since coming into the scratch builders scene over six months ago, costing only 88 cents per sheet and weighing in at 134 grams, sporting a brighter whiter finish, distributed by Walmart lets give a big welcome to the challenger - Ross Foam Core Board (applause).

Coming into this competition, Ross has a slight advantage of costing 12 cents less than Adams. However, even with that advantage, Ross has a real disadvantage because he is stepping into the ring at 20 grams heavier than Adams, a clear disadvantage for those looking to trim every gram off of each build. But, 20 grams or 12 cents should not be a huge factor for determining which material to use. Ross entered the building circuit over the summer and has demonstrated that he is able to hold together even in wet conditions, an environment that causes Adams to just melt. That resilience might be the dominating characteristic that will decide the winner of the competition tonight.

As we all know, during flights, Adams biggest weaknesses as a building material for aircraft is its propensity to delaminate. Once that happens his resilience is gone and he just falls apart. Moisture is his archenemy so he has to be kept dry. There has been a huge amount of effort by many fans on ways to protect Adams from moisture. My solution to this debilitating characteristic was accomplished by removing the paper skin altogether and re-skinning the foam with fiberglass and other papers impregnated with polycrylic. My efforts resulted in an article: Super Strong, Waterproof Foam Core. In that article, I compared the strength of plain Adams to Adams’ foam with different skins including popular choices like Kraft paper, Packing paper, Tape or my favorite, Fiberglass.

What about this newcomer, Ross? Over the summer, it seems Walmart has produced a real winner. Ross rose from obscurity and in a short time has popped into existence and is catching everyone’s well deserved attention. Since being introduced to the scratch builders circuit, he has won over the hearts and minds of pilots that have to deal with moisture on a daily basis. Bout after bout with water, Ross comes through with hardly a dent. There has been a lot of discussion and excitement over the Ross because of two very attractive features, he is $0.88 per sheet that is the same size as Adams, 20”x30” and (BEST OF ALL) Ross’ paper skin doesn’t peel from the foam, even if it gets wet!

The ring is set… Offaxis provided a great review article and started a forum thread and did an excellent job of comparing the basic physical features of Ross to Adams in both the article and forum on topics of Size, Thickness, Weight per full sheet, Price, Flatness, Brightness of paper, Paper Quality, Crush Test, Paper Peel, Rigidity Comments, Fold Test, A and B style folds, Foam Bevels with sharp knife, Foam Bevels with a sanding block, Painting and Water Delamination. He even built a float plane with Ross foam board and demonstrated its indifference to water by crashing in a lake, drying the plane and flying again. Truly we have a winner here… but just how far can he go… we will see it all tonight!

I really like the fact the Ross doesn’t peel when it gets wet, and I’ll keep saying it. I often fly in the morning and land on dewy grass - which completely hoses aircraft made with Adams. My experience with Ross has solidified my opinion that this rising star is far superior to Adams. I have seen his past performance, for example, I built the F/A-18 Hornet using Adams (Version 1) and duplicated the build for version 2 and 3 using Ross. After two flights in the humid air, the F/A-18v1 (made from Adams) had bowed wings and delaminating crease along its left wing root. I took it flying just to see if I could break the wings off - here is the result:

Interestingly, as hard as I tried to break it… it wouldn’t break, but the flying characteristics sure changed as the plane’s wings bent upward. Versions 2 and 3 (made with Ross foam core) are still flying and are loads of fun.

Even though Ross demonstrated its amazing anti-delaminating properties when it gets damp, the paper covering still gets soggy and looses its stiffness so flat surfaces (like the wings of the F/A-18) get pretty flimsy. Foam core resurfaced with fiberglass never gets flimsy - like my Glassed FT-22 and Supersized FT-22. I still really like fiberglass skinned foam - tough and waterproof.

I am a scientist by training, and I seems to have an instinct to gather data and compare outcomes... so I thought I would put Ross through the same paces of reskinning with fiberglass and other papers/tape to see how it compares to Adams in a head-to-head competition. If you want details on how to peel and re-skin the foam, please go to the previous article Super Strong, Waterproof Foam Core.

So, let’s get ready to rumble…ding, ding, ding.

The main event competition uses a single piece of foam core 5 cm x 50.8 cm (the width of the board).

After re-skinning with the various materials, the foam sandwiches were allowed to dry/cure for a week.

To measure strength, the foam core is laid flat between two blocks 48 cm apart and weight is added to the center of the foam span until it breaks.

The weight held by the foam is recorded as well as the deflection distance and the weight of the re-skinned foam.

Weight difference between Readi-Board and ROSS

My data indicates that a 5x50 cm strip of Readi-Board weighs 7.63 g and the Ross weighs 8.35 g - Ross is slightly heavier. After peeling Readi-Board foam weighs 3.65 g and the Ross foam weighs 4.27 g. The difference indicates that the paper of both weighs the almost the same (3.98 g vs. 4.08 g).

Peeling Ross. Peeling the paper from Ross is a lot more difficult that peeling Readi-Board. I found that the paper can be peeled if it is lifted away from the foam at about a 90 degree angle, lay the foam on the table and pull the paper up toward the ceiling. The foam gets pulls quite a bit demonstrating it is strongly bound to the paper.

The interesting thing about peeling Ross foam core is, like a fiberglass skin, when the paper is peeled from the foam, the foam actually tears and you can see the foam pieces on the paper. This indicates that the foam is the weak link in the foam/paper sandwich. Adams peels without any effort and leaves nothing on the paper.

Abbreviations. For clarity, the charts that follow use the following terminology. The type of foam, whether Readi-Board (RB) or ROSS is in the legend. The next is a -P or +P: -P means the paper was peeled from the foam, +P means the paper was left on and overlayed with more material. The following letters represent the adhesive for the new skin PC is PolyCrylic water-based and Epoxy is epoxy resin used in the fiberglass layups. The last letters are the material used in the reskin: Kraft is Kraft paper from Walmart, Pack is packing paper from Walmart, Tape is clear packing tape, RR is red rosin paper (home depot) FG is fiberglass at 0.73 oz/sqyd, 1.43 oz/sqyd or 3.15 oz/sqyd. Again, details of these materials can be found in the previous article Super Strong Waterproof Foam Core.

Strength Comparison In the rounds that follow, we will witness a contest of strength, we will see how Adams and Ross are able to hold up increasing amounts of weight. The statistics of each round below is sorted by increasing amounts held by the Adams (Adams RB in the blue corner, Ross in the red corner).

Round one - no alteration. A head to head strength comparison of Adams to Ross when both are left in their original paper skins. The second group from the left (+P) is the Adams RB and Ross with their original paper skin left on - both hold the same amount of weight. Round one is a draw.

Round two- recovering Adams and Ross foam with Kraft paper using polycrylic (far left -P PC Kraft). Ross comes out of the corner with a smile, clearly he has an advantage over Adams… Ross’ foam covered with Kraft paper is as strong as the original, however, Adams seems to have lost some strength, after the first round he is looking pretty tired. Using polycrylic and Kraft paper does make the sandwiches completely waterproof, so if this is the goal it is one way to go, but there are other better options below. Clearly, Ross takes this round.

Round three- recovering with Packing Paper using polycrylic (-P PC Pack). Packing paper is much lighter than Kraft paper and can be adhered to the foam with either polycrylic or epoxy resin (and I’m sure latex paint, floor glue, or any number of adhesives). Ross came out of his corner looking very confident. This round used polycrylic as the adhesive… and we can see that it adds a little strength to Ross but Adams gained nothing and is as a matter of fact, no stronger than the original paper. If you are looking for the same strength but waterproof, resurface the foam in packing paper with polycrylic. Round three again goes to Ross.

Round four- recovering with Packing Paper using epoxy resin (-P Epoxy Pack). Both Adams and Ross got a boost of energy from this combination, but Ross seemed to truly capitalize on his advantages holding much more weight through this round than Adams. Round four clearly goes to Ross.

Round five- resurfacing with fiberglass at 0.73 oz/yd (-P Epoxy FG 0.73). Ross seems to be a bit off in his tempo. He came off just a little stronger than Adams this round, both contestants holding more than their original but not so super strong that it is worth the effort . Maybe this will bring the confidence back to Adams that has been missing since the draw in round one.

Round six- adding tape over the paper skin (+P Tape). Wow, we’ve seen a turn in events during this round. Adams came out of his corner with a grimace and determination. Tape on Ross unexpectedly did not perform as well as Tape on Adams. As a matter of fact, adding tape over Ross didn’t add much strength at all. A possible explanation is that tape doesn’t adhere as well to Ross as it does to Adams, at least that is the impression I got when trying to peel the tape off of the foam core. The tape could be removed from Ross pretty easily, however Adams’ paper came off with the tape. Adams come out of round six looking like the champ we remember. Round six goes to Adams.

Round seven- recovering with Red Rosin paper using polycrylic (-P PC RR). In the past, red rosin paper has boosted Adams’ energy level. Again we see the same great performance from Adams, but Ross seems to have stumbled with this kind of cover showing a relative weakness. I think the trainer was wishing he put more polycrylic onto Ross before applying the red rosin paper. To late to retry… Round seven goes to Adams.

Round eight - resurfacing with fiberglass using epoxy resin (-P epoxy FG 1.43). Wow, what a round. Adams performed amazingly during this round, but Ross must have found some lost momentum and out paced Adams in holding the weight. This is the weight of fiberglass that I like to use. It is very strong and easy to work with. The lighter stuff is really expensive and hard to keep flat. The trainer recommends this profile. Ross take this round.

Round nine, the final round - resurfacing with fiberglass using epoxy resin (-P Epoxy FG 3.15). This was a surprising round. Ross seems to have stumbled. Adams took the heavier fiberglass skin and performed optimally. It appears to me that the laminating process on the Ross was incomplete or his trainer just didn’t teach him the trick because stronger skin should have really boosted his performance but it didn’t. Adams clearly took this round, but I’d charge the deficit to Ross’ trainer, he should have performed much better given the performance of other fiberglass skins. Ross returns to his corner holding up his hands like victory is his. It is a close one.

Oncore performance by Ross

While we wait for the decision, wait a minute, Ross is dancing in the middle of the ring. It looks like he thinks he has won. Hold on, this looks like an oncore performance, yes... Ross throws in an exhibition that Adams is unable to perform. Because Ross’ paper doesn’t peel, his paper is able to be treated with adhesive materials like polycrylic and epoxy. The first exhibition Ross demonstrated that if you paint him down with polycrylic he becomes stronger (+P PC). This may be a great way to waterproof the paper on Ross so that he doesn’t sag or get soft in the moisture. The second exhibition was to douse Ross in epoxy resin (+P Epoxy). Epoxy cures harder than polycrylic, so he come out stronger and waterproof. Great exhibitions here this evening. I wonder if paint or other materials provides Ross with additional energy as well as a moisture barrier.

Analyzing the statistics - Strength to Weight Ratio

The judges have returned. The first round was a draw, Ross took 5 rounds and Adams took 3. Looks like we have a new world champion folks! But there is more to consider… there is always a weight penalty to increased strength. Looking at the strength to weight ratio, is a great way to compare which combination has the most strength for its weight.

Ranking the competitors this way demonstrates that both Adams and Ross are pretty evenly matched. Except for the tape which doesn’t stick to the Ross as well. Ross’ trainer argues the Red Rosin and heavier fiberglass was a construction error and has little to do with the foam’s performance. Nonetheless, the results show an even split… 4 for Adams and 4 for Ross with a marginal difference of the non-altered foam core.

Tape - This comparison shows that there is little benefit of putting Tape over Ross, it adds weight and doesn’t stick that well, but maybe this is a fault of the tape the trainer used (Scotch brand Moving and Storage packing tape) but it may be a powdery coating on the paper. Putting tape over Adams, however, increased its strength quite a bit. I imagine that if the tape were to stick to the Ross like Adam, there would be a benefit - but I wasn’t about to buy all sorts of tape to test. While tape prevents superficial moisture from getting to the foam core, it does not waterproof it. Moisture has a way of finding its way to the paper, and Adams will still delaminate leaving you with a delaminated paper covered in tape. If you have used tape on Ross and it holds, please post a comment on what kind of tape. Because Ross performed so poorly with tape covering, this covering goes to Adams, without question.

 Packing Paper - There is little benefit of peeling the paper and using polycrylic and packing paper but there is a benefit if epoxy resin is used. The benefit of epoxy is that is cures into a stiffer surface than polycrylic. Maybe if I would have let it dry for a few months, the polycrylic would produce a stiff foam core… but I never wait a month to fly my planes. Regardless, Ross with packing paper using either polycrylic or epoxy as the adhesive beats up on Adams.

 Red Rosin Paper - One head scratcher is the round with red rosin (RR) paper. With the Adams foam, it added a lot of strength, but there is no benefit with the Ross foam. This result surprised me and I don’t have an explanation. The benefit of using red rosin paper is that it would withstand exposure to moisture since it is laminated in polycrylic. An additional note is that you gain this property if you simply “paint the Ross foam core with polycrylic. The paper still hangs on and it gets stronger (+P PC on the far right). I wonder if the trainer used enough polycrylic to make a nice bond from the foam to the paper.

Fiberglass - Resurfacing with fiberglass, regardless of the fiberglass weight, had an overall benefit of strength to both contestants. Looks like I must have messed up in with the heavier fiberglass (3.16 oz/yd) because it didn’t hold up as I expected on the Ross. I don’t use that heavy stuff very often so I didn’t feel like repeating that round. I typically use the 1.43 oz/yd fiberglass for resurfacing foam. The benefit of resurfacing with fiberglass is that it is stiff and completely waterproof. Even though Ross doesn’t peel when it gets wet, it does get soft and limp. I was flying on a very humid day and the wings of the plane got flappy. After it dried, it seemed to be fine, but it was pretty spongy in the sky. I add a note that paper shrinks after getting wet, so flat foam core surfaces tend to warp. These rounds seem to be a draw because no matter which foam core you choose, fiberglass performs equally well on either.

Adams vs. Ross

Conclusion - Personal Preferences and Recommendations. At this point in time, I have built four planes out of Ross foam board. My summary is that it feels like Readi-Board, it folds like Readi-Board, it builds like Readi-Board, it glues like Readi-Board, flies like Readi-Board, breaks like Readi-Board and it tastes like Readi-Board (just kidding). I have painted the planes with water based acrylic using an airbrush on the Ross foam core and it doesn’t peel. I have landed the unpainted Ross planes in dewy grass and they are still flying. My opinion, Ross beats Adams hands down on the qualities that count for model building. I have yet to experience any reason why Adams would be used if both are available (unless you are setting out to peel and resurface - in this case Adams is the winner).

Tape on the Ross’s bare foam doesn’t stick and the outcome is pretty flimsy. Don’t do it! Tape over the foam core paper works really well with Adams, but not so well with Ross. It may be that the paper used on Ross has some powdery coat from the manufacturing process that prevents complete adhesion. Using or not using tape depends on the goal. If the goal of using tape is to prevent moisture from delaminating the paper from the foam, just go for the Ross - it doesn’t need protecting. If the goal is the add color, I’d suggest using Ross and paint. If the goal is to get stronger surfaces, well, tape makes a stronger and slick surface, but with a weight penalty. I have only used tape to hold a leading edge of a wing together, but it may not stick on the Ross.

Kraft Paper If you are going to resurface the Adams or Ross foam, I think there are better alternatives to the Kraft paper (at least the stuff I picked up at Walmart). It adds weight and you get no additional strength laying flat. It does, however, make a hard puncture resistant surface, but remains bendy when flat. So if you want something strong but not stiff, the Kraft paper is the way to go. Before you discount Kraft Paper altogether, when built into more structural configurations, like a square box, it gets significantly stronger.

Packing Paper If you need a surface on the foam that is stiff and light, resurface the foam with Packing Paper and use epoxy resin as an adhesive (if you have it), otherwise, polycrylic does nicely. Packing Paper feels like a really heavy tissue paper. This combination is waterproof, strong, light and adds quite a bit of stiffness for the weight. I think the next best thing is to “paint” the ROSS foam core with polycrylic or epoxy resin. You will get a stiff, strong waterproof coat without the hassle of peeling the paper off of the foam.

Fiberglass I am still super impressed by the results of resurfacing foam with fiberglass. Above all, it has the added benefit of staying stiff when wet. The strength to weight ratio is a real positive. So, for a quick build and prototypes, I will use Ross, but for the long-lasting finished planes that I can fly all year, I will still resurface the foam with fiberglass. As I have said, Ross’ paper doesn’t peel off the foam easily. I may still use Adams Read-Board for the fiberglass skinning because it peels easily. I’ve been toying with the idea of surfacing over the Ross’ paper with fiberglass. I’ll let you know how it goes. It may be doubly strong and awesome.

Final Note Keep in mind that this competition was designed to stress the most vulnerable orientation of the foam core, laying flat. If the pieces were built into square tubes, or configurations that have more structural geometry, they would hold significantly more weight. The bottom line is that all of the materials used to cover or recover the foam have unique characteristics that can be to their advantage. Happy Building!

HilldaFlyer - December 2015

I hope this was a little more entertaining than a scientific study. If you have questions - post a comment or I can be reached through the FliteTest Forums.

It appears the Adams has changed the kind of paper they are using on the Readi-Board. Follow the discussion on the forums: New Adams Foam Board?

FT is now offering water resistant foam core: Water Resistant Flite Test Foam