Rubber vs. Plastic Boats
Rafts come in all shapes sizes colors and textures; however the composition of their materials is a hotly debated topic in the river community. There are two basic compositions for whitewater rafts rubber or plastic. These categories are not hard and fast rules but general guidelines and many raft manufactures are beginning to move to divergent fusions to try to mitigate the weaknesses and maximize the advantages of different materials. Whichever boat that you choose to purchase or use make sure you know the advantages and disadvantages of each craft before you buy.
These boats are the classic whitewater raft with origins dating back before World War II. In fact many early commercial rafts were military surplus rafts picked up by outfitters. Today modern designs and new materials have created plenty of great boats that last for decades. If you prefer a raft that feels stable on the water and easy to sit in, rubber rafts will have a special place in your fleet.
Rubber rafts are typically made from chlorosulfonated polyethylene a synthetic rubber often marketed under the DuPont® trademark Hypalon®. This material is a strong chemical resistant material that makes up the bulk of whitewater raft material. Layers of this are sandwiched around a woven Kevlar mesh to provide an exceptional material for whitewater rafts. In addition, it makes for quick and easy repairs to the vessel when the boat becomes damaged.
- Often heavy
- Wraps hard
- Losses rigidity with age
- Higher drag coefficent
- Seams can delaminate in hot conditions
- Easy to repair
- Less prone to flipping
- More grippy seats
- Easy to roll/packs down
- Feels stable on the water
Storing rubber boats can be very easy because of the pliable nature of the materials. Rubber boats are easy to roll and transport however, if they are stored for long periods, rolled rubber has the tendency to bond to itself. This creates problems when you remove your raft from long term (2-3 months+) storage especially when rolled. The exterior surface tends to delaminate from the underlying fiber layer. This problem can be mitigated with a generous application of talcum powder before you store it for long periods. Unfortunately you may still find that your boat will bond to itself even when powdered especially in humid conditions. Because of this problem many boaters who use their rubber rafts infrequently often complain of reduced life expectancy and delamination problems.
Recently we have noticed a new trend emerging from the rubber boat manufacturers of adding urethane chafer strips to the floor and bottoms of the tubes. This will give you some of the advantages of a plastic boat’s ability to slip over rocks and giving the boat a sportier feel. The disadvantage comes from the fact that patching any damage at the seam of the chafer strips an absolute nightmare because of the multiple compositions of the materials.
If you enjoy slipping over rocks and running slides this is the boat for you. Plastic boats tend to lead the industry in terms of sportiness, speed, and sliding over obstacles. Many designs feature diminishing tubes which some boaters prefer and some hate depending upon their boating preferences.
PVC or Poly Vinyl Chloride is a cheap easily manufactured synthetic plastic polymer used by most of the lower end raft manufacturers. PVC is typically welded together through various methods at the seams in the tubes. PVC’s greatest weakness is the fact that it is brittle at or below room temperature (not a good quality for us boaters).
Rafts made from urethane enjoy a number of advantages over their PVC counterparts and the higher end raft manufacturers, like SOTAR, use Urethane as their go to material for building rafts. This material has elastomeric memory properties, meaning it will return to its original form when stretched, as well as being non-brittle resisting cracking under shock loading.
- Less prone to wrapping
- Shallow draft
- High rigidity especially when punching waves
- More punctures and rip resistance
- Slides over rocks obstructions easily
- Lower drag coefficient
- Sporty feel on the water
- Plastic can flake off with age
- More prone to flipping
- Prone to shattering with impact especially when cold (PVC Boats)
- Limited elasticity (PVC Boats)
- Hard to roll
- Can feel unstable
Storing plastic boats can be a bit trickier in comparison to their rubber counterparts. Plastic boats don’t really like to be rolled and they generally do not pack down well when you try to roll them. The best way to store one of these boats is laid out flat, so if you do purchase one ideally you should have a flat open garage or storage area to lay it out on. Unlike their rubber counterparts you don’t need to worry about delamination from material sticking together when you store them over a winter.
"All of our seams are welded including the seats and chafers." -Joe, SOTAR
Welded seams are one major improvement that higher end manufacturers like SOTAR have latched onto over their rubber counterparts thereby eliminating delamination that rubber boats often experience in storage.
Some of the lower end manufacturers have begun to slap rubber chafer strips to the top of the tubes on the seat area as a stop gap measure for the slipperiness of the seat problem. This is a nice benefit, but if the chafer strip is too large or the boat is a big boat it tends to add a lot of weight to the boat negating the sportiness of a plastic boat. Serious manufacturers like SOTAR has an array of options to help reduce weight and add amazing amounts of grip to the seat without sacrificing performance.
So what should I buy?
Much like surfers have multiple boards in their quiver to accommodate different conditions, as rafters we will often develop diverse fleets especially if you run many different types of rivers.
Like my ol' pappy used to say "Boy don't use a screw driver to pound a nail."
The best advice if you are looking for a first purchase or to add a new boat to the fleet is to follow the "over 50% rule". Ask yourself what you are going to be running over 50% of the time with your boat. Then, demo some different rafts to get a feel for what you feel comfortable with. Next, ask people in your area and those who share your boating style and preference what they prefer to boat on. Finally, find a boat with the features that you want for a price that you can afford.
Unfortunately there is not one catch all boat to fit every circumstance. A commercial outfitter has a different preference to a racer or an expedition boater. The local conditions, your boating style and your personal preferences will play a huge factor in what you should use.
If you still have questions feel free to contact us and we can try to point you in the right direction.