Tag Archives: anfibio skeg

Sigma TXL: floor-mounted skeg and foam backrest

Sigma TXL Index Page

After various trials I decided for sailing the TXL would benefit with a skeg on the floor where it would be fully submerged except momentarily when cresting bigger waves. The standard position angled on the stern (left) sits too high on the buoyant TXL so doesn’t have much effect, though the TXL tracks pretty well on flat water, with or without the air floor, solo or two up. You can mount the skeg back-to-front (right) for more bite, but I hope tracking when sailing will be greatly improved with a fully immersed skeg. When the wind allows, I want the TXL to be a reliable sailer on longer paddles.

Under the floor stays fully submerged, even with the air floor.

I could’ve simply made an extension to the stock skeg, but decided having two positions for the stock skeg would be less bulky. Like on an IK or a SUP board, the long but shallow Anfibio skeg would work well mounted horizontally under the floor (above, left). I’d already tried a skeg under the bow, but that did not work well at all. Waiting for good glue, I’d stuck that front skeg patch on with Aquasure and was surprised how easily it peeled off with less than a minute with the hairdryer.

Just as I was about to clean the removed patch and glue it on with Helaplast (recommended by Anfibio), I thought super tacky Gorilla Patch & Seal tape would be even easier, using the spare Anfibio skeg patch as a template. But I decided P&S is just thick ‘rubber’ tape suited to sealing, not supporting a knocked about skeg. In fact regular, string backed Gorilla ‘duct’ tape would have worked (a good way to test the idea), and I’ve found lasts surprisingly well on a packboat. In the end I decided the liberated fabric-backed Anfibio patch would be best.

The most important thing is to mount the patch straight along the centre line otherwise you’ll be going round in circles. This is best judged with the boat inflated. After that, it’s the same Helaplast sequence as detailed here. While gluing, I decided to add a couple of tabs low in the front to make the thigh straps hook more effectively over the knees.

The benefit of having two positions for the rear skeg instead of a bigger fin is that you can choose: use the standard position for shallow rivers (if a skeg is even needed) and use the floor mount on open water where wind and waves may push the boat around more, and if you hope to sail in a straight line.


Foam backrest
Sat up front, the stock inflatable backrest (below left) does the job, but in a low-pressure boat, the air cushion just adds more mushiness where you want support. As I say in the book or on Seats: sit on air; lean on foam. There is no advantage to inflated backrests other than saving a bit of packed space (might they also be cheaper to produce?). In this way, regular solo packrafts, where you lean on the back of the boat are better. Seated centrally in the TXL, you need a supportive IK-style backrest.

After a few outings I’ve decided to replace it with a spare foam SoT backrest (below), an idea which has worked well on my IKs for years. IK makers too have a blind spot when it comes to front seats. Today’s price for the backrest on ebayUK is 17 quid (left). Once I ditched the heavy ‘brass’ clips which came with mine, it weighs 200g, only 40g more than the Anfibio item (the ebay one shown left uses lighter plastic spring clips).

The foam backrest fits right on the TXL: the long tapes reuse the TXL’s front buckles and, less well, the rear straps come back through the flat tab mounts. A slide ring would work better here. I could have reused the thin, cinchable elastic cord which came with the Anfibio backrest but I suspect it was part of the problem (and thought so on the Anfibio Revo too). Counter-tensioned, non-elastic straps attached to a firm panel add up to better support. Up to a point the thinner foam backrest also makes more room behind it, too. And I won’t miss deflating the stock backrest to save on packed space, neither!

Inflatable kayaks: Do you Need a Skeg (Tracking Fin)?

Updated Summer 2022

See also:
About rudders
About decks

Skeg-wheel trolley!

Short answer: Yes.

Generic, over-tall Chinese-made skeg.
Snap-prone but easy to trim.

A skeg is like a fixed ‘rudder’ under the back of the boat and makes it easier to go straight (track). Only the very cheapest single-skin vinyl IKs don’t have skegs (Grabner, one of the most expensive IKs, is an exception; though it’s an option). If you’re IK doesn’t have one, it’s easy to glue one on (see below).

grabgumskeg

Some flat-floored IKS have up to three (imo, a gimmick) and many skegs on Chinese-made IKs are unnecessarily tall (too deep) which makes them snap-prone. Just about all skegs can be easily removed by hand, because in shallow rivers you might want to do so to avoid grounding. You can as easily buy a spare and trim it with a hacksaw.

Original over-sized Gumotex alloy skeg on the left. Later smaller; now tough plastic.

Years ago Gumotex introduced a slip-on, black plastic tracking fin (skeg, above) which was near identical in shape to one I’d had made to replace the old-style oversized alloy skeg (left). A smaller skeg made better clearance and still tracked fine. But metal bends; tough plastic is much better and that’s what all their boats come with now.
I’ve fitted these plastic skegs to older Gumotex IKs and other IKs. The kit is about £25 + glue, and the plastic skeg is pretty much unbreakable. Just make sure you glue the mounting patch on really well; it helps if your boat is made from a matching rubber fabric as the supplied Nitrilon patch or make your own patch from same fabric. But I have glued PVC to rubber successfully – use good two-part glue. The pictures below help you see where to position a skeg.

I fitted the Gumotex plastic skeg to my Grabner Amigo IK (above) and at sea used it all the time. But on the shallow River Spey (below) this boat didn’t handle at all well without a skeg, possibly because the tailwind pushed the kicked-up stern around. It was really quite annoying because a few years earlier my broadly similar Sunny managed the Spey just fine without a skeg, so skeg-free tracking clearly varies from boat to boat.

spey1304

Paddling without a skeg
If you’re an experienced paddler you’ll have acquired the knack of going straight without a skeg – handy for paddling shallow rivers where the skeg would ground. A little more paddling finesse and constant small corrections are required, especially if powering on.
It’s good to learn this technique before you need to: fix your eyes on a tree or marker on a distant bank and paddle as gently as you like towards it, not looking away and keeping the nose of the boat in line with the marker. By using very light strokes you’ll see it can be done if it’s not too windy when again, a skeg helps with tracking (going straight).

cezesolar
Gumo Solar with no skeg

I even found I could paddle a ten-foot Solar 300 (above) without a skeg. Once you know you can go straight without a skeg, it’s just a matter of adopting the same finesse but with a bit more power. Only when you attempt the speeds of a Viking longship will bow deflection or yawing get too much because to paddle faster and still go straight you need a skeg. Out at sea or on busier rivers, I always use a skeg.

I’ve often thought a hinged retractable skeg would be a good idea: it would pivot backwards when dragging in shallows, then drop back down when there’s enough depth. It seems SUPs need skegs and in the US, FrogFish have made such a thing for boards, but you hear the spring can be a weak point.
If your kayak has a rudder mount (or you can make one), another way of doing it is fitting a swing-down skeg similar to kayak rudders. It works the same way as a rudder with a looped cord swinging the skeg up over the stern, or down into the water. The pivot skeg shown top right is made by Advanced Elements for their AirFusion IK and costs about $/£80. Or have a look here.

Packrafts

On shorter, wider, slower solo packrafts the consensus used to be that skegs made little difference. Especially when unloaded and with a full-weight paddler, the bow yaws merrily left to right as your paddling pivots the boat from the back. Or so I used to think until I tried the skeg on my Rebel 2K. Up to then I’d been ambivalent about them – using the same boat fully loaded a few weeks earlier on a fast flowing river, yawing had not been an issue. But unloaded (and with my generous 95kg of ballast) yawing was notably reduced with a skeg. Speed however, was the same or was too small to measure.

Longer stern puts you more in the middle of the boat.

One reason some packrafts may manage without a skeg is that way back in 2011 Alpacka invented the ingenious extended stern (right). It helped limit yawing much like a skeg, and effectively positioned the paddler more centrally, like a kayak, while also adding trim.
This idea has been widely copied by just about everyone since and it definitely works, compared to the original Alpackas. But as mentioned, once there’s a good load over the bow, yawing is reduced in any packraft. Anfibio sell a detachable shallow skeg and glue-on patch for €21. My Rebel 2K came with a skeg and I must admit I use it most of the time now. But it does not have a fully extended stern like the Alpacka above right. Then again, my longer Nomad tracked great without the skeg.

Frontal skeg?
Now I have a longer 2.8-m Anfibio Sigma TXL and I am curious to see if adding a frontal skeg will take a difference. Seated centrally or two-up, this boat does not yaw from the boat like an unloaded solo packraft, but it does wander a bit (track poorly), especially with the inflated floor pad). Results soon.