Lining Off

Before we started lining off - finishing of the timbering took another couple of tries. We got better as things proceeded learning that we needed less steam and less force than we thought. By the third batch of timbers (John came up trumps with some great quarter sawn stock) the steaming time (for the 20mm x 20mm timbers) was cut back to an hour and we were having fewer and fewer problems.

The next boat (ha!) should be much easier.

The first ‘problem’ that had worried us was easily solved by advice from Justin. The penultimate timbers lodged on top of the endmost molds and we had no easy way of securing the timbers so that the timber can be released before we turn the boat over. Most of the timbers are secured at the garboard end by screwing through the innermost ribband from underneath. The screw can then be removed before we try and turn the boat over. This strategy would not work for the penultimate timber because the mold prevents access to the underside of the timber from inside the boat. After considering strapping wire over the timber and tensioning it to the sides of the mold we were rescued by Justin. ‘Just bevel the timber and but it under the apron’. With a temporary dab of epoxy between the apron and the timber we can then remove the temporary holding screw before we plank the boat. A little cleanup work with a scraper will be a small price for an elegant solution.

Here is the timber - with the temporary screw still in place before the epoxy gets dabbed between the timber and the apron.

The other problem we noticed after timbering (and one that we had anticipated) was that the pressure from the timbers at the garboard (next to the hog/keel) would pull the ribband upwards and distort the line of the timber into the hog. This time we were saved by advice from John. We placed lengths of batten sideways under each area of the innermost ribband (to which the timber was secured) and used large wood screws to tension down the ribband to the required level.

But with all these small items sorted out - we had ‘timbered out’ our first boat. Here she is - a real skeleton.

And from the inside - a real minature wooden cathedral. You can see why church roofs used to be built by shipwrights.

And after all this we had to ‘line off’.

Lining Off is the process of deciding how planks will lie across a boat - how many planks to use and what shape they will take. The general principle is that the plank lines on a boat, particularly above the waterline, should look harmonious and graceful. This process is only of significant concern for a traditionally planked boat (carvel or clinker). A strip planked boat (subsequently covered in glass and resin) is lined on a basis that is more practical than aesthetic. It might seem obvious, but is worth stating, that the planks on a boat are all tapered. In order to look good, the planks’ tapers should be co-ordinated. Some of this work can be done mathematically but some of it involves trial and error (with lining off battens - not planks) in order to judge what looks harmonious by eye. The critical plank is the one adjacent to the keel (the garboard strake) as it determines how wide the remaining planks are as they join the stem and transom (or in the case of the Seapod that I am building - the stern stem). If the garboard is too short the plank lines up the stem appear to dive into the water - if the garboard is too long the planks appear too pointed and can’t be fastened to the stem properly. Lining out the garboard is, we found, the really hard bit. To really judge what is going on you really have to see the boat the right way up - and as we are building upside down this means bending over and looking at the boat upside down. We did a lot of this on Wednesday and Thursday.

Here is the lining out batten pinned on the the garboard. The lower edge of the batten (in this picture) represents the edge of the plank.

We decide to make some gains amidships on the first three planks and then plank more or less uniformly up to the sheer strake. Half way down it looks like…

And once we get finished we have a layout for 11 planks each side - photo inverted to make things easier…

We draw in the lines underneath all the batten, remove them and then record all the plank dimensions. Once I look at the dimensions I realise that this is just the first approximation to how the planks will need to be lined in order to look fair. The confusion of molds, ribbands, timbers and lining out battens creates such a complex visual field - spotting ‘fairness’ is much harder than you might think. However, we have a planking strategy and can now move forward.

Having machined up a few planks on Thursday we start on the Garboard proper the next day (Friday). We make up plywood templates for the ends of the plank, spile the keel side of the plank and lay it out on some planking stock. The batten fairs the curve(s) and we are ready to cut our first plank - right on schedule.

In the foreground - to the right of the batten you can see the tighter curve that the plank takes as it meets the stem.

We finish the week having come a long way….