Semperit Forelle 2; afternoon refurb’

Here in the Summer Isles the reliable May sunny spell is about to end. It’s been great for solar panels with strong afternoon easterlies, not so good for day-long IK-ing. Suilven mountain even caught fire. Yesterday, before it picked up we nipped out in the Seawave to Eilean Fada Beag (below) and listened to the birds. By the afternoon it was blowing hard.

High time to patch up my latest IK: an old Semperit Forelle 2 I picked up in Cornwall. The boat was sold with some classic paddles which went straight in the bin, as well as a big tear in the side (right). Plan is to patch that hole, then see if it still holds air.

Semperit is an Austrian tyre manufacturer who’s still in business. Afaik, their IKs were a bit of a short-lived rubbery diversion in the 1960s. If my 40-year-old boat has no other more awkward leaks, I’ll rig it up and take it for a spin. But first, I scrubbed off a couple of decades of crud and let it dry.

I wondered about sewing up that L-tear before patching it – the Forelle’s hypalon seems pretty thin, but decided to just slap on a 5-incher. I’ve glued on loads of accessory patches but have never actually had to repair a hole in a hypalon IK in all these years. So I took note of the NRS repair video here: rough up hole and patch: wipe clean with solvent; apply two coats of glue and when knuckle dry apply the patch and roller the living daylights out of it.

Watching that vid, I saw they used a much better tool for pressing down patches; an ash-handled Sealey TST15 tyre patch roller, unless I’m very much mistaken. The knurled metal wheel embedded in the wooden handle can lay down much more pressure than the wide plastic lino roller I’ve been using.
Just before I did that, it occurred to me stray glue may squeeze through the tear and glue the insides together. Don’t want that nein danke so, with no better ideas, I stuck a bit of paper in there. Seems to have worked.

With glue left over, I thought I may as well stick on couple of floor patches for a seat base and a footrest tube. As these are non-critical fittings I used any old D-rings I had: a woven nylon one and probably a PVC. I’ve glued PVC to hypalon before for other fittings.

With them in place I couldn’t resist rigging up the old Trout with a rope-and-pipe-lagging backrest, an old Alpacka packraft seatbase; a drainpipe footrest tube and a lead. All stuff I happened to have in my IK box of bits or found in the barn among the rat droppings. I jury-rigged the K-Pump for nozzeling but haven’t pumped it right up to 2psi as I’m letting that big patch cure for a bit.

Looking round the repaired boat I see it has rudder mounts; not sure I’ll need one on a 3.56m boat. There are six D-rings on top of the double side tubes but they don’t look like they’ll take the backwards strain of a fabric backrest Forelles came with wooden backrest bars, (like Grabners who took over Semperit) and which I’ve found prone to bending when used with a firm footrest tube.

There’s also a squished up full-length keel strip along the bottom. If it works for tracking it will be nice not to have the usual skeg-grounding aggro in shallows or on land. But maybe that keel will slow down turning which is why they have the rudder attachment? We shall see. With twin side tubes the Forelle is just 70cm wide – that’s <28″. But with a thin floor and me sat low in the high sides I’m sure it will be stable enough.
Gumotex still use them for their seats, but the ‘lilo plugs‘ on the three chambers are a bit of a faff for getting a good charge of air.

If the Semp proves viable, I may replace them with proper IK valves. Or I may just leave them as they are. Three £15 Gumotex valves + a £20 PRV will cost the same as the boat, and the lilo plugs can be regarded as their own ‘total loss’ PRVs – when the boat gets too hot they pop! And anyway, there’s no room to fit a big IK valve in the floor as the tubes are too close together. Knock-off Halkey valves go for 7 quid; I might stick a couple in the sides and leave the lilo plug in the floor.

I put it back in the barn with my other restoration project for a couple of days. When I came back it was limp but not draped over that cabinet like a wet pizza. I pumped up and it stayed firm enough, though I’ve forgotten how mushy an 0.2 bar IK feels. It reminds me why I seriously took the idea of trying to increase the rigidity of my old Sunny before getting other IKs. At the beach I filled it with water and stones – no obvious leaks, (or so I thought). A testament to 40-year-old hypalon and glue.

Have to say too, once pumped up, for an IK the old trout is not bad looking. I think the discreet upsweep of the bow, that plywood ice breaker and slender twin tubes make it look a lot less of a bloat than some. Sea trials to follow.