SOF fabric

I may have asked before, but can’t find it in the archives.

What are my choices for SOF fabric other than neoprene and what do I use for sealing them?

Does Spar varnish on nylon work?

There are many choices
I’ve used 8 oz. Nylon, which is probably the most commonly used fabric, plus 9, 10 and 13 oz. polyester. The 8-9 oz. fabrics are easier to sew and conform readily to curves. The 10 oz polyester isn’t bad to work with, but the 13 oz. is a bear to stitch tightly.

Polyester takes finishes better, but Nylon works well with oil-based varnishes (do not use water-borne finishes on Nylon). My personal favorite is ZAR exterior satin polyurethane, but others will work. There are several two-part products that offer improved durability, but at a steep price.

Check out this site

I had been to skinboats site and the
materials are very pricey. This boat will be seldom used by my grandsons , so I’ll go with Bryan’s suggestion. Thanks.

Actually not
First I agree with Brians suggestion FWIW. I have used 8oz and 12oz nylon. 12oz came from George Dyson and I had no problems with it. But I like the 8oz better.

ZAR is my choice too. Just be sure and find the oil based exterior. It was hard as heck to find around here.

And when you shop around you will see that Skin Boat prices are not that out of line and they are good quality. They service is lacking however. Slow to ship and never answer emails questions. But I would still buy from them, just order well in advance of the need by date.

Aircraft fabric?
Does anyone use aircraft fabric? I’ve used heat-shrink polyester on an airplane – it conforms nicely and is certainly strong enough, but I don’t know about puncture and abrasion resistance in kayaking scenarios.

The expensive certified stuff is here:

And a non-certified version is here:

A builder at kayakforum uses aircraft dacron, but covers it with a thin layer of fiberglass to give puncture resistance - it apparently has little otherwise.

Most US skinboat builders seem to use material from skinboats or Dyson. There is also a filter fabric manufacturer that shows skin boats as an application:

You can check out the formums at for much banter on boat fabric.

IMO, aircraft Dacron isn’t suitable

– Last Updated: May-07-09 9:57 AM EST –

While it sounds ideal with it's shrinking ability and all, it's way too light. The heaviest aircraft Dacron I've seen is 3.7 oz./yard and the lightest fabric recommended for SOFs is 8 oz. You certainly could use the lighter fabric, but you'd have to be very careful with it. Personally, I wouldn't go there.

makes sense
It’s designed for distributed loads, not point loads or abrasion.

I helped re-cover an airplane using the Poly-Fiber process, which gives you a UV-resistant vinyl coating bonded to the fabric.

Grandsons? How Old and Size?
Hey String, there is a real nice fellow down near Colombia, SC I could hook you up with if you hit me off-line.

Tons of stuff on the web, you could even use canvas and polyurethane over a frame

I should have expressed my opinion, which is in line with Bryan - I don’t believe the aircraft dacron is suitable either. The person who uses it does so in a multi-step application - he’s quite experienced and has developed a unique system which sounds complicated, very light, and somewhat finicky. The rest of us humans should use the regular good stuff.

My seamstress and I are going
shopping Saturday for 8-10 oz nylon . The ONLY way she will get me in a fabric store.

that guy on the other forum
Hi Carl,

I’m that guy on the other forum that uses dacron/fiberglass :slight_smile:

Works just fine, the dacron alone is strong except in puncture resistance and once a tear starts it’ll grow very quickly. (not alot of sharp rocks to run into in an airplane). The fiberglass covering is simple if you’ve used glass/epoxy before, just requires the dacron to be pre-coated in resin first to provide a stable surface for the glass to applied to. This makes for a very durable and rugged cover for a SOF. I’m working on covering my 5th. yak with it now.

I’ve used both 6 and 4 ounce glass, the heavier material is definately more rugged, but also adds weight and is hard to get a smooth surface finish with. I use the uncertified dacron from Aircraft Spruce and use the 3 ounce material. The lighter fabric would likely work too, but only reduces the weight a tiny bit.

Bill H.

Hi Bill
Not sure you wanted to be indentified specifically on another forum, so I played it coy. I certainly believe that your system is a good one in the engineering sense, although maybe it’s more involved than a casual sof builder would care to attempt. In particular, you wouldn’t recommend using the shrinkable dacron without a reinforcing layer, would you?

Also, I’ve never really asked, so what do you think the major benefit of your system is, compared to ballistic nylon with a urethane coating.

Cheers, Carl