DIY dropstitch Inflatable foil boards? We can do this!

[fluidity]

Here is a video showing the effect of adding the disruptors. Does show release is cleaner and occurs at a lower speed than w/o the disruptors.

Thanks for that!
Not sure if you changed them? but the disruptors should extend flat in line with a flat on the board and the curve should be glued to the start of the curve on the board. When I looked at your board in motion it seemed like they were forward of how I fit them?

[RTL78901]

Thanks. I realized that a bit too late. I am planing on putting them on the right way.

[RTL78901]

Here is strange situation sort of on topic (I hope). My really cheap ISUP developed a leak under the center fin. This caused the fin base to bulge and eventually leak out. The really strange part is there was a bulge on top of the board. This made me think the yarn threads were broken to create the bulge on top. So I removed the old fin base and patched the hole. There was a rough spot on the base which apparently caused the leak. Having done so seems to have flattened out the bulge on top. Can't really see why the top bulge would have been fixed by removing the fin base. Anyway, now I plan to put an Air-7 fin box where the cheap base was which should impove speed and upwind. (Along with the disruptors shown). Pictures attached.

Does anyone have an idea how to attach a full windsurf sail to the top of a cheap paddle board. Supfly Mallorca has a product that looks promising, but they apparently do not ship to the US.

https://www.supfly.store/paddle_windsur ... urfer.html

[nixmatters]

Does anyone have an idea how to attach a full windsurf sail to the top of a cheap paddle board. Supfly Mallorca has a product that looks promising, but they apparently do not ship to the US.

Duotone have this:
https://shop.duotonesports.com/en-gb/ad ... 4200--8011

As for the stick-on fin for iSUPs, JP have a spare base + 10' fin.

[RTL78901]

Thanks.I'll look into the the Duotone product but I think it is for their inflatable sail. I have just been gluing the fin boxes on w/o the PVC cover that would certainly make it stronger. So far I've had no problems.

[fluidity]

Here is strange situation sort of on topic (I hope). My really cheap ISUP developed a leak under the center fin. This caused the fin base to bulge and eventually leak out. The really strange part is there was a bulge on top of the board. This made me think the yarn threads were broken to create the bulge on top. So I removed the old fin base and patched the hole. There was a rough spot on the base which apparently caused the leak. Having done so seems to have flattened out the bulge on top. Can't really see why the top bulge would have been fixed by removing the fin base. Anyway, now I plan to put an Air-7 fin box where the cheap base was which should impove speed and upwind. (Along with the disruptors shown). Pictures attached.

Does anyone have an idea how to attach a full windsurf sail to the top of a cheap paddle board. Supfly Mallorca has a product that looks promising, but they apparently do not ship to the US.

https://www.supfly.store/paddle_windsur ... urfer.html

Is that one of the aliexpress ISUPs?
I'm wondering if the stitching got loose inside above the defect you discovered under your fin? If so, I can't quite see how you could reinstate the integrity of the dropstitch just with glue but lets hope... Some people are very anti the ISUPs but usually without trying. I built myself a fibreglass board with volume under my body weight and I'm loving it, but at moment I'm hanging on to my ISUP for a summer sale or family if they decide to try.

[RTL78901]

I like ISUP simply because they are light and portable. The board was branded funwater which is listed on Alibaba and Ebay as well as operating its own web based business in the US. Very cheap, esp. at the end of the season (249 US$). The link below is their web page. The video is a pretty comical demo of how tough their boards are. The leak in my board developed because of a small burr in the fin box which eventually tore the single layer of PVC - rather than any of the things shown in the video. Anyway, it gave me the opportunity to replace the cheap fin box with a good one.

https://www.alibaba.com/product-detail/ ... jFqBoi&s=p

The bulge on the bottom of the board was simply due to air being released under the finbox (which was not glued to the board) causing it to bend upward and stretching the PVC cover (which was glued to the board). Once that was fixed (by removing the fin box) it flattened out when I pumped it up. I'm now gluing the Air-7 fin box on and it is still flat. The strange part is there was also a bulge on the top side of the board under the deck pad. Perhaps it is due to broken yarns but will only show up when the board gets hot out in the sun. Or maybe it is just an air bubble between the deck pad and the PVC? Or it could be the bending of the fin box had the effect of causing a small bulge on the top. I don't know. TBH - I didn't expect to be able to fix this board, but decided to try. So far, so good.

[nixmatters]

The strange part is there was also a bulge on the top side of the board under the deck pad. Perhaps it is due to broken yarns but will only show up when the board gets hot out in the sun. Or maybe it is just an air bubble between the deck pad and the PVC? Or it could be the bending of the fin box had the effect of causing a small bulge on the top. I don't know.

The bulge on the top was most likely due to the pressure built up at the bottom, between the dropstitch skin and the fin box, pushing the dropstitch skin.
But I still don't get how there was a leak at the bottom if there is no seam there?

[fluidity]

The strange part is there was also a bulge on the top side of the board under the deck pad. Perhaps it is due to broken yarns but will only show up when the board gets hot out in the sun. Or maybe it is just an air bubble between the deck pad and the PVC? Or it could be the bending of the fin box had the effect of causing a small bulge on the top. I don't know.

The bulge on the top was most likely due to the pressure built up at the bottom, between the dropstitch skin and the fin box, pushing the dropstitch skin.
But I still don't get how there was a leak at the bottom if there is no seam there?

You beat me to it about the top bulge.
My guess though on the leak is a moment's slip in concentration from the worker scuffing the under side before gluing the fin. With a power tool!

[RTL78901]

Thanks guys. It makes perfect sense. I took the board out yesterday and it worked fine.