Outstanding work, SHig, I envious because of not having enough time to pursue something like this due to work demands, so I will keep your pursuits bookmarked.
Maybe a more compact , lighweight valve like the alpaca is available and could be moved to the upper front edge between the legs without having to sit on it. A backrest would add considerably to comfort which is important to me with my spine troubles, but make the thing heavier. Sometimes you can justify slightly heavier weight/volume in packing if something does double or triple duty- like an alpaca that also serves as an elevated sleeping mattress, emergency shelter, etc… I have by far the lightest setup of all my buddies in the ODC 420 which has allowed transport by air travel to some really beautiful water. Even inflatable kayaks aren’t stable enough to enjoy these in comfort. The bells and whistles are nice on a fully loaded tube, but at some point it limits you to drive and drop locations only. The weight gets too heavy for wheels, and everything gets more complicated to set up, transport and use.
Pon
Looking good! Just that valve on the seat looks like it might be a little uncomfortable…LOL Or not
Larry Tullis, one of the main designers for North Fork Outdoors (Scadden)
He has been doing this awhile.
I am still interested in SHigs findings.
So you don’t plan on putting any kind of material over this?
And next, why so light? What is the final / everything / loaded and headed out weight you are looking for?
This plastic sheeting is just for prototyping. The final product will be heat sealable urethane coated nylon. The two bladders you see there complete should be right at 2 lbs.
Outstanding work, SHig, I envious because of not having enough time to pursue something like this due to work demands, so I will keep your pursuits bookmarked.
Maybe a more compact , lighweight valve like the alpaca is available and could be moved to the upper front edge between the legs without having to sit on it. A backrest would add considerably to comfort which is important to me with my spine troubles, but make the thing heavier. Sometimes you can justify slightly heavier weight/volume in packing if something does double or triple duty- like an alpaca that also serves as an elevated sleeping mattress, emergency shelter, etc… I have by far the lightest setup of all my buddies in the ODC 420 which has allowed transport by air travel to some really beautiful water. Even inflatable kayaks aren’t stable enough to enjoy these in comfort. The bells and whistles are nice on a fully loaded tube, but at some point it limits you to drive and drop locations only. The weight gets too heavy for wheels, and everything gets more complicated to set up, transport and use.
Pon
Looking good! Just that valve on the seat looks like it might be a little uncomfortable…LOL Or not
The valve on there is strictly for modeling purposes. I’ll be using those clear, flush mount valves for both the seat and the main bladder. Backrest is doable, but not high on the list. I figure a simple inflatable backrest with a sling that you sit on to adjust the rake like a stadium seat. Only put you back a couple of ounces probably. The ODC lightweight is a nice boat, my friend has one, but this is 1/4 the weight, and will pack down to maybe 1/4 the volume or less. I had considered making the seat removable with the backrest so you could use it as a camp chair, but really, probably not worth the complexity and added stresses due to compromises. You COULD just deflate the main bladder and sit on this, but watch out for sticks and rocks!
The statium seat is exactly what Scadden uses. Specially made and soooooo comfortable. But the weight of one of those plus your tube, you would be looking at close to the Trinity wouldn’t you?
The statium seat is exactly what Scadden uses. Specially made and soooooo comfortable. But the weight of one of those plus your tube, you would be looking at close to the Trinity wouldn’t you?
Not even close! The tube is 2 lbs, inflatable backrest and straps won’t weigh more than a few ounces. The Trinity is 6 lbs and won’t come close to how small mine will roll.
Outstanding work, SHig, I envious because of not having enough time to pursue something like this due to work demands, so I will keep your pursuits bookmarked.
Maybe a more compact , lighweight valve like the alpaca is available and could be moved to the upper front edge between the legs without having to sit on it. A backrest would add considerably to comfort which is important to me with my spine troubles, but make the thing heavier. Sometimes you can justify slightly heavier weight/volume in packing if something does double or triple duty- like an alpaca that also serves as an elevated sleeping mattress, emergency shelter, etc… I have by far the lightest setup of all my buddies in the ODC 420 which has allowed transport by air travel to some really beautiful water. Even inflatable kayaks aren’t stable enough to enjoy these in comfort. The bells and whistles are nice on a fully loaded tube, but at some point it limits you to drive and drop locations only. The weight gets too heavy for wheels, and everything gets more complicated to set up, transport and use.
Pon
Looking good! Just that valve on the seat looks like it might be a little uncomfortable…LOL Or not
The valve on there is strictly for modeling purposes. I’ll be using those clear, flush mount valves for both the seat and the main bladder. Backrest is doable, but not high on the list. I figure a simple inflatable backrest with a sling that you sit on to adjust the rake like a stadium seat. Only put you back a couple of ounces probably. The ODC lightweight is a nice boat, my friend has one, but this is 1/4 the weight, and will pack down to maybe 1/4 the volume or less.
**Yes, I think less is more especially in packing, and so admire your project. But there are some of us out there that dont have much free time, and are forced to compromise with a 420L or alpaca, cost being quickly recovered from wages. A 420 can be made somewhat smaller to pack in terms of volume by removing the bladders and stuffing into smaller nooks, which also balances the load.
Pon **
I had considered making the seat removable with the backrest so you could use it as a camp chair, but really, probably not worth the complexity and added stresses due to compromises. You COULD just deflate the main bladder and sit on this, but watch out for sticks and rocks!
I came home from work tonight to find a box on my porch. Funny, I don’t recall ordering any seasoned deli wedge chicken batter recipe frozen potatoes… Hmm…
I especially love this handling caution:
Oh yeah, this is probably my fabric and hardware!
Sure enough, my materials showed up as promised… Kinda…
Fabric-a-palooza!:
The blaze orange is for my tube, the grey is for Jay’s super-stealth stupid simple delete-option special.
So why “kinda”? Well according to the distributor, the fabric was supposed to be 58" wide and 60" wide, but what I got instead was 56-1/4" to 56-1/2". Grr! I can work around it, but it limits how long I can extend the pontoons out front if need be.
Anyway, I was eager to start playing around with the material.
First thing I did was rail the iron as I was told to use the cotton/max heat. I folded the fabric over and placed some paper over it to protect and proceeded to iron it. Oops… Either it was too hot (probably) or I missed the corner with the paper (likely).
Here’s another, cooler setting weld:
You can see that the press and temp are pretty good as the welded material is flat, not wrinkly or wavy, and some of the urethane coating is squeezing out. Seems right. The backside isn’t as crisp a straight line on the weld as I’d like, but I’m not sure what’s good and what’s not - yet.
So, what am I doing you ask?
What’s this?:
Or this?
Yup, I’m building a peel strength testing jig. The fabric is 1.25" wide and the loop on either end are such that I should be putting even stress across the ribbon. The trick is to make sure I hold the screwdriver level and have the loop on the button level as well.
Next I put some water in the bucket, weighed it, suspended it by the test strip and held my breath…
So far so good. That blemish/white area about 3/4 across is just an area of “different” bonding. With the proper edge template I’m confident I can create a nice tight consistent line of weld.
Next:
Good! At this point I should mention that at max normal lung inflation pressure of 2 psi, the seam stress in a 12" round tube would be 12 lbs of peel per inch. On my test strip that’d be 15 lbs. So already, we’re beyond “normal” stress on the tube.
More water!!:
Now we’re seeing some stress. You can see in the last photo where I’ve unloaded it some whitening of the seam boundary. I believe that what’s happening there is the uneven seam edge is “leveling” itself such that it starts to peel until it reaches a nice straight line of loading, then it’s holding. I don’t think that this is affecting the ultimate strength of the bond or the air barrier. At this weight, we’re simulating 3.8 psi - nearly double normal max lung inflation. Or normal inflation to 2 psi and leaving it in the sun to heat up to 500 degrees above when you inflated it.
More likely, though, it’s modeling inflating at sea level then driving up to 3500’. This is why you should NEVER inflate your tube until you get to where you’re going.
BTW, here’s a link to a great chart showing what air pressure is doing as you climb. Each psi reduced as you climb is a psi gained inside the tube so be careful!
Now we’re seeing some strain. Still, it doesn’t seem to be creeping in peel, and unstressed it doesn’t look much if any different than the last test. At this weight we’re up to 4.4 psi.
At this point, instead of loading in more water, I started bouncing the bucket a bit in the stretch of the fabric and… THWACK!!! Game over!
What you notice, though, is that the glue held. The FABRIC is what failed. Based on this result, it seems like the goofy and not as finished exterior butt weld stressed in peel is NOT limited by the coating adhesion. This is a very good thing!
Also, I did this test using the 70 Denier fabric - the lighter weight of the two. I’ll be using the 70D for the lighter stressed seat and other areas while using a much beefier 200D for the main tube - where the big stresses will be seen at the higher pressures.
What this tells me is that I MAY be able to use the 70D in the main tube to save as much as 7 ounces overall if I go all 70D. For now, I’ll play it safe and stronger with the 200D main/70D seat.
I will be conducting this test again with 200D to see if the fabric failure holds true for the heavier material, and to see how much higher I can go with the bucket. One thing I do know was that I was near the top of the bucket with the water so I may have to daisy-chain or start chuckin’ lead in there too!
Also, I would like to do an endurance test at elevated loading to see if the coating does creep over time. Maybe then add heat?
I also have a pressure gauge and will be building a mock pontoon tube and doing some stress tests on it via lung-power and pump idiocy to see what’ll happen. If I remember I’ll shoot video to see if I get a ka-BAM!
Okay ladies and gents, exciting progress tonight. I wanted to do a full blown (pun intended?) bladder tonight so I made a fully sealed “drybag”. Did it so it was slightly bigger in diameter at the middle than the tube to make the pressure vs. seam stress as bad or worse.
I’m going to try some video this time. Bear with me here…
GRRR!!! Can anyone tell me if it’s possible to embed flickr or youtube videos on this forum?
Anyway, here’s a LINK to the initial inflation:
I didn’t go full tight because I wanted to make certain that the perimeter welds were nice and straight and full.
Here’s a LINK to the “Ping Test”. I think at this point I’d maxed out my lung capacity and said “screw it” and used the pump to go WAY harder than I’d ever taken my Fish Cat (and I enjoy a “ping tight” tube). I think the gauge read around 3 psi:
And finally, after the pillow was stupid hard, I decided to really lay it on Samsonite gorilla style:
Mind you, I was using the LIGHTER fabric. This is the fabric I plan to use on the lighter stressed seat, while using the heavier fabric for the main bladder.
I’m pretty sure that I won’t be having any problems as long as I can keep making good consistent seams.
Seams:
Here’s the only section of seam where I feel that I didn’t get it quite right. You can see a bit of a bulge that’s not in line with the rest of the seal, but I could go back over it and re-heat it. Don’t think I need to though.
Here’s the whole pillow in all of its glory!:
So, I think it’s time to start cutting some patterns! Wish me luck…
Those are coming out really strong and nice. Good job!
How are you going to do the channels in your seat if the fabric only seals on one side? Is there enough coating to seal when you use one good side bonded to one lightly coated side?
Very impressive testing results. On my “V” tube the underside of the seat seems to take most of the wear from floating over rocks and sand. Depending on your design, might you need a slightly thicker fabric layer on the bottom of the seat section? Just saying…
Those are coming out really strong and nice. Good job!
How are you going to do the channels in your seat if the fabric only seals on one side? Is there enough coating to seal when you use one good side bonded to one lightly coated side?
Just like the plastic model. All bonding is coating to coating only.
Very impressive testing results. On my “V” tube the underside of the seat seems to take most of the wear from floating over rocks and sand. Depending on your design, might you need a slightly thicker fabric layer on the bottom of the seat section? Just saying…
Pon
Basically, the operator needs to understand the trade-offs and limitations of the craft and not let the boat touch bottom. It’d be simple enough to replace the seat with the heavier of the two materials though. It would add about 3 ounces to the boat.
OTOH, based on the results of this test, I’d say I could make the whole tube out of the lighter material and save 7 ounces, bringing the weight down to around 1 pound 9 oz.
My Bad! I think my brain hadn’t turned on yet this morning!
I was thinking in terms of a finished sewing project where the seams are all on the inside.
You are doing a great job, and I am really impressed by how much testing and experimenting you are doing. Now I keep thinking of all kinds of things I could with this stuff. Hmmmm…
