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[colin-stevens]

This kind of continues on from a previous thread I started back in 2020. I have now laid up the hull frames, all mounted on a board, square and true(ish). However I have noticed a few errors, the biggest is the fact that the "top" of the frames (moulds) are not level. 1& 2 are fine, the line starts to get less at 3, and is gone at 4. Starts to come back at 5. Not sure if this is the way its meant to be, but the pencil lines you see are marked using a long flexible steel ruler, with the bottom of the ruler following  the "top" of the frames to give a reference line. I have checked my templates and that side of it is ok. If I was to leave it as it is the "top" of the hull will dip in the middle. So, do i leave it, and plank using existing line, and see what happens, or cut in an infill piece to build out the frame so that the top plank runs straight and level.
Advise gratefully received

[SailorGreg]

Not sure what you are building, but most hulls have a sheer (level of the bulwark or deck edge viewed from the side) which is curved rather than a dead straight line.  In nearly all cases, that curve starts high at the bow, dips towards midships then rises a bit towards the stern (but not as high as the bow).  If your frames describe a curve like that, they are probably spot on.  That curve should be smooth when viewed along the hull from front or back, not kinked or stepped.  The picture below pinched off the internet.



That said there are hulls with reverse sheer, where the midships is higher than the bow or stern, and some with a combination where the sheer starts to rise from the bow, then sweeps down and back up to the stern.  But from your pictures, I would guess your hull has a sheer as shown in the picture.

Greg

[RST]

Hi,


If it helps is it by any chance a "River Queen" from a quick check of your previous posts, particularly the wording of the "moulds" i.e. the hull is pulled out after seems similar from before on your previous posts?  I saw a flared steam funnel and an awning in the plans in the back of your photo here but that doesn't necessarily fit width the River Queen pics I can find?


...In any case, if you have drawn the sections out reference an arbitrary straight base-line from the body plan then everything should fit ref. the straight baseboard.  You're definitely on the right track from the photos fitting it out on the baseboard though. How the side of the shell fits (i.e. sheer for and aft) depends on your markings but if your keel is right I would have thought most things would be aligned against it.  Also, ref your .pdf link on the thread back in 2020 it mentions fairing, yes this should be done.  It's far too long since I did PoF and I'm not used to small boat terms but the same principles apply to most hulls using egg-box construction or larger sheets rather than planks.  I always try to use a very long sanding block or "sanding bow" to fair the sections to roughly the right taper before applying the planking, or skins.  I thought your .pdf explained it quite well apart from fairing before planking but there are very good books out there on the subject.  For sure though, if you have a dip like I think I can see in one of your pics as you describe, it is not right, either a section isn't right vertically, or you haven't faired them out between them yet.  Planking as-is would only replicate the dip you describe.  Not sure from your description whether they are not placed right or not faired yet but sounds like the former.


Is it worth you combining the old thread you mentioned with this (you can ask a mod to do it) so that it's a bit more joined up please?  I found your old "2020" thread pretty quick from looking at your previous posts in your profile but not sure if it's the right one?


Not sure if this helps at all.  I should leave it to others to advise better when the build is a bit better clarified.


Rich