reelfishin
Captain
- Joined
- Mar 19, 2007
- Messages
- 3,043
Let me start by saying that I began today looking for a substitute for the 1/2" MDO bench seat tops in my Grumman boat. Someone suggested that since it's only an 18" span, maybe Starboard would be an option, I agreed and drove over to the building supply who used to carry Starboard, but what I found might be a far better option. First, I was told that Starboard was no longer sold there, which pretty much had me headed for the door, but when a began to explain what I needed it for, a sale rep there handed me a sample of something new. It was a 3/4" cut of PVC panel, it's made by Certainteed, the insulation and trim people. It looks like wood on the face sides, but the side view looks more like dense foam. What came to mind was the more modern composite decking used in some higher end boats, I remember seeing something similar at a recent boat show. I took one sample home, a piece about the size of 8" long 1x4, and did some research online as well as read over the data sheet they had there for it. It compares to wood in load rating and strength with only slightly more deflection rating over larger expanses. For instance, a 4' long board cut from this stuff would be slightly more flexible than the equal cut of plywood or solid board. Weight wise, it's about 6% lighter, meaning that if it took using a thicker panel to regain any needed strength, no weight would likely be added.
It is called cellular PVC panel. It is not the foam like stuff that Home Depo sells and is far lighter per length. A deck screw buried into it seats much like wood, not pulling through and popping out the other side like the fake wood decking material from HD.
Cost wise, it's about double the cost of the same nominal marine ply.
It mills and drills like wood, but has no grain, therefore no directional strength preference. With no fiber structure, I would not think it a good choice for a transom, but I'm thinking that it may be a good choice for decks, seating and other interior areas where would is normally used.
It won't rot, it won't split, and it's supposed to be highly UV resistant. It's intended to be used unpainted and can be milled the same as wood if used as trim, it comes in nominal sizes and sheets both smooth and wood textured.
What I am thinking is to use the 3/4" for my bench seat tops, it will no doubt be plenty strong, permanent, and by far longer lasting than the original 1/2" MDO. The span is only 16.5", so it will no doubt hold up to that task.
I am seriously thinking of trying to use it for a couple of smaller transoms, on small aluminum boats that run less than 25 hp motors. It would no doubt be more than strong enough compared to the 8" tall by 54" span of plywood that's in there now. I don't think that it would be an option for a larger boat, where major horsepower was a factor, and I don't think it would take well to laminating two panels together. I think if I do try it as a transom panel in a small boat, I'll attach an aluminum clamp panel where the motor clamps sit.
I did take one of the samples and clamp down a trolling motor to it, its harder than wood and it leaves no impression, but I would think that once the smooth surface was worn through, it may loose its surface strength. It does crush in a vise, but it don't crumble, it reacted mush like wood to pressure. It also seems to hold self tapping screws very much the same as wood. I drilled a suitable hole, ran in a 1/4" lag bolt to the point of penetration, and tried to pull it out like a nail, and that wasn't going to happen using only a claw hammer as my pry bar, I then tried the same, but this time trying to strip the bolt out in the PVC panel, by using the same screw to secure two pieces together, the screw did strip out but provided normal holding strenth up to the point where I forced it beyond it's required torque.
It does have a far more strength with the outer layer in tact, but even once that layer is punctured, it still retains the fastener. I do not think it's as strong near it's edges as wood would be, but it would no doubt make a perfect boat deck so long as the stringers were not overly far apart. I am seriously thinking of doing my deck in my one aluminum boat with it but my stringers are less than 15" apart. It would no doubt span that area without any noticeable flex.
The best way to describe this stuff is that a piece in hand, about the size of a 1x4" board about two foot long shows no flex by arm or by hand, and your eyes closed impression is the same as wood in touch and weight. A 6' long cut of the 3/4" panel about 12" wide showed a good amount of flex, probably equal to a length of 5/8" plywood of the same length. I could not snap the 1x4 length by hand, nor could I break it by hand by wedging one end in a vise, but I could stomp it in two over a curb, where it snapped with about half the effort as it's equal cut in plywood would have.
I would venture to guess that a double thickness of 3/4" glued or mechanically fastened together and cut into a transom panel for my 14' aluminum boat would not exhibit any noticeable flex by any manual force.
It's not anything like the artificial decking sold at the big box stores, it's the closest thing to wood I've seen yet and its far cheaper than Starboard, and far lighter and far more rigid.
I have a few 3/4" pieces of Starboard, and it's weakess points are weight and flex, along with edge breakage. This stuff takes care of at least two of those problems, and is probably twice as less likely to break on the edges as Starboard if struck.
I am even considering maybe using the thinner version but really don't see where there would be any real advantage since it wouldn't be a great weight savings.
Has anyone any experience with this material?
Here's some pics of the sample:
http://i43.tinypic.com/slhaut.jpg
http://i39.tinypic.com/2j4r21l.jpg
http://i43.tinypic.com/34zexck.jpg
http://i42.tinypic.com/sv3qjb.jpg
http://i40.tinypic.com/2u4sr36.jpg
It is called cellular PVC panel. It is not the foam like stuff that Home Depo sells and is far lighter per length. A deck screw buried into it seats much like wood, not pulling through and popping out the other side like the fake wood decking material from HD.
Cost wise, it's about double the cost of the same nominal marine ply.
It mills and drills like wood, but has no grain, therefore no directional strength preference. With no fiber structure, I would not think it a good choice for a transom, but I'm thinking that it may be a good choice for decks, seating and other interior areas where would is normally used.
It won't rot, it won't split, and it's supposed to be highly UV resistant. It's intended to be used unpainted and can be milled the same as wood if used as trim, it comes in nominal sizes and sheets both smooth and wood textured.
What I am thinking is to use the 3/4" for my bench seat tops, it will no doubt be plenty strong, permanent, and by far longer lasting than the original 1/2" MDO. The span is only 16.5", so it will no doubt hold up to that task.
I am seriously thinking of trying to use it for a couple of smaller transoms, on small aluminum boats that run less than 25 hp motors. It would no doubt be more than strong enough compared to the 8" tall by 54" span of plywood that's in there now. I don't think that it would be an option for a larger boat, where major horsepower was a factor, and I don't think it would take well to laminating two panels together. I think if I do try it as a transom panel in a small boat, I'll attach an aluminum clamp panel where the motor clamps sit.
I did take one of the samples and clamp down a trolling motor to it, its harder than wood and it leaves no impression, but I would think that once the smooth surface was worn through, it may loose its surface strength. It does crush in a vise, but it don't crumble, it reacted mush like wood to pressure. It also seems to hold self tapping screws very much the same as wood. I drilled a suitable hole, ran in a 1/4" lag bolt to the point of penetration, and tried to pull it out like a nail, and that wasn't going to happen using only a claw hammer as my pry bar, I then tried the same, but this time trying to strip the bolt out in the PVC panel, by using the same screw to secure two pieces together, the screw did strip out but provided normal holding strenth up to the point where I forced it beyond it's required torque.
It does have a far more strength with the outer layer in tact, but even once that layer is punctured, it still retains the fastener. I do not think it's as strong near it's edges as wood would be, but it would no doubt make a perfect boat deck so long as the stringers were not overly far apart. I am seriously thinking of doing my deck in my one aluminum boat with it but my stringers are less than 15" apart. It would no doubt span that area without any noticeable flex.
The best way to describe this stuff is that a piece in hand, about the size of a 1x4" board about two foot long shows no flex by arm or by hand, and your eyes closed impression is the same as wood in touch and weight. A 6' long cut of the 3/4" panel about 12" wide showed a good amount of flex, probably equal to a length of 5/8" plywood of the same length. I could not snap the 1x4 length by hand, nor could I break it by hand by wedging one end in a vise, but I could stomp it in two over a curb, where it snapped with about half the effort as it's equal cut in plywood would have.
I would venture to guess that a double thickness of 3/4" glued or mechanically fastened together and cut into a transom panel for my 14' aluminum boat would not exhibit any noticeable flex by any manual force.
It's not anything like the artificial decking sold at the big box stores, it's the closest thing to wood I've seen yet and its far cheaper than Starboard, and far lighter and far more rigid.
I have a few 3/4" pieces of Starboard, and it's weakess points are weight and flex, along with edge breakage. This stuff takes care of at least two of those problems, and is probably twice as less likely to break on the edges as Starboard if struck.
I am even considering maybe using the thinner version but really don't see where there would be any real advantage since it wouldn't be a great weight savings.
Has anyone any experience with this material?
Here's some pics of the sample:
http://i43.tinypic.com/slhaut.jpg
http://i39.tinypic.com/2j4r21l.jpg
http://i43.tinypic.com/34zexck.jpg
http://i42.tinypic.com/sv3qjb.jpg
http://i40.tinypic.com/2u4sr36.jpg
