Help please :-) New build, cracks and splits in planking....

alick burt

LOVES Wooden Canoes
Hello Folks
Some months ago I took delivery of a form for a 16ft wood canvas prospector.
The form has been made by its previous owner and he had also begun planking.During a lull in my other activities I continued with the planking using yellow cedar which he had bought and prepared.
I found this really difficult as the planks kept splitting despite soaking with swabs of boiling water and attempts with a steam iron.It seemed many splits occurred on the final few blows of the hammer when trying to make the tack heads flush.After much trial and error I had reached a stage of about half the planking being complete with some minor cracks in the ends on some.
Then I got busy with other work and it sat untouched for a few months.
I now find myself away from the workshop in lock down but I expect that when things improve I will not be overwhelmed with work so will have time to continue with this canoe once my outstanding work is completed.
The last time I looked at it I noticed even more cracks in the planks as they had dried out.I am thinking if I was to replace all the cracked planks I will be almost starting again as even those that aren't too bad still have maybe one or two cracks half an inch long where the tacks are.
Before anyone asks I did pre-drill the planking and sorry but I haven't any pictures yet though once I get back to the workshop I may take some.
Other thoughts I have had is that the planking may have been too dry.I have noticed that it was kiln dried which could explain the problems.
Now to my questions.
1.Should I soak the planking before fitting it? I was reluctant to do this as I was thinking it would expand and then make big gaps between planks when it eventually dries?
2.Should I remove/replace all the cracked planks still on the hull or can the cracks be filled in any way?
3.Am I on a hiding to nothing using kiln dried timber?
4.Should I actually boil the planking? I read that Joe Seliga did this...
5.Finally I have some areas towards the bow and stern where it looks like I will need some long thin tapered pieces between planks and am wondering how this will be achieved or should I also re think my planking pattern to avoid them? Once again sorry I don't have pictures yet.
6.Should I reduce the width of my planking? it is currently around 2.5 inches.
Thank you in advance all help gratefully received.
Stay safe.
Alick
 
Just popped in to see what was going on and saw this. I am sure others with more experience will add, but here's a thought or two. I wonder if it is the type of wood, yellow cedar, or the way is sawn, or that it was kiln dried.?? I would not soak for reasons you think, i.e. cracks. I've only used western red and northern white cedar. Flat sawn planking is not nearly as good as quarter sawn for me. So, is it something you can live with or would there be structure issues? Always decisions to be made and compromises to consider.
Regards,
Dave.
 
Thanks Dave
I think it is a mixture of flat sawn with some quarter sawn. The batch came from the same planks sawn through and through so there are some good ones which have been allocated to the more curved areas.In the UK white cedar is impossible to get hence the original owner bought yellow as an alternative.I have access to red cedar as I use this to make strip canoes with so might that be a better alternative?
I'm not sure about the structural issues of the cracks but have heard they will show up once I get to filling and painting stage that was why I was thinking filling might be the answer...
 
What type of tacks or nails are you using? Brass canoe tacks should go through pretty easily. I have planked with air dried yellow cedar, quarter sawn and have not had any problems. Mostly when red or yellow cedar splits on me, it is because I have driven the tack in on and angle by accident and then that final blow drives grain apart. If you feel the need to pre-drill, then maybe the tacks/nails are too large.
 
Hi Rod
Thank you for your reply. Your air dried would perhaps be better than my kiln dried....
I think the tacks are the recommended size and shape.Once again they were bought by the original maker but they have the correct shape and are proper canoe tacks.From memory I think they are the recommended length and gauge too though I will double check when I finally get back to work.
 
What are you using to pre-drill?

I was taught to pre-drill using a small brad (not sure of the diameter) with the head cut off. The pyramidal point) separates the fibres of the wood rather than shearing it like a drill bit would. The size of the hole relative to the shank of the tack may be the key
Striking the tack in line with the shank may also be a factor.

I have never used yellow cedar, only red and white. Where the hull is curved, I wet the outside surface to promote cupping. Where the curve is extreme it also helps to apply a steam iron as mentioned above.
 
Might slathering on some linseed oil help? If the wood is dry and the oil is absorbed deeply it might help it get back some of its flexibility.
 
Alick - I'd be thinking first about making sure your wood is an outside humidity rather than inside humidity. My thoughts suggest the planks are shrinking causing the cracking.
I've bent up yellow cedar for ribs no problem and also used it for planking (but never on very curved areas) and it has been fine. I've no idea whether my piece is kiln or air dried and no easy means of measuring the moisture content, but it lives just a draughty garage door away from the English weather and wouldn't know what heating was.
 
What are you using to pre-drill?

I was taught to pre-drill using a small brad (not sure of the diameter) with the head cut off. The pyramidal point) separates the fibres of the wood rather than shearing it like a drill bit would. The size of the hole relative to the shank of the tack may be the key
Striking the tack in line with the shank may also be a factor.

I have never used yellow cedar, only red and white. Where the hull is curved, I wet the outside surface to promote cupping. Where the curve is extreme it also helps to apply a steam iron as mentioned above.
Hi Rob
Thank you, some interesting thoughts.I used a drill bit and am sure it was big enough I am also used to using nails to make holes so may try that as an alternative.I have managed to drive them in straight so I don't think that is the problem.
 
Might slathering on some linseed oil help? If the wood is dry and the oil is absorbed deeply it might help it get back some of its flexibility.
Hi Howie
Thank you for your reply.That never occurred to me as an idea at this stage of the project so might be worth a go...
 
Alick - I'd be thinking first about making sure your wood is an outside humidity rather than inside humidity. My thoughts suggest the planks are shrinking causing the cracking.
I've bent up yellow cedar for ribs no problem and also used it for planking (but never on very curved areas) and it has been fine. I've no idea whether my piece is kiln or air dried and no easy means of measuring the moisture content, but it lives just a draughty garage door away from the English weather and wouldn't know what heating was.
Hi Sam
Thanks for your reply and hope you are keeping well.
My workshop is pretty much un-heated or at least the heat only extends to the small area around the stove most of the time so I don't think it has been over dry once it arrived but of course i don't know how hot it was in the previous owners workshop.
I do have the bill for the timber which shows it was kiln dried and it wouldn't surprise me if this is the source of my troubles.I have read that once this has been done it isn't even possible to soak the timber and return it to flexible condition because the structure of the timber is forever changed but I would be interested to hear other peoples experience of that as from what I have seen timber always moves in response to moisture.
Maybe I should leave it outside for a few months....
 
Hello Folks
Now that I have been able to get to the workshop I have managed to take a few pictures of the cracked planks.I think there are less than I thought but you can see what I am dealing with.
One picture shows the bow stern planking where I think i have somehow ended up with a need for some fine tapered pieces between the other planks.Can anyone enlighten me as to how these can be fixed or should I re jig my planking plan to eliminate this type of gap at the bow?
The same goes for areas where I have cut away cracked bits and am left with planking the replace that is only about 10 or 12 inches long.Should I also remove more planking to make replacement planks longer in these areas?
Of my cracks which ones would people call structural and which not?
Also if filled in some way will they still show?
 

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Alick, how thick is your planking? May just be my eyes however it looks thick where the edges are visible. The combination of being flat sawn, dry and thick might be causing it to split from the hammer blows? Doesn’t look to be countersinking much either, but then again I can’t claim any familiarity with yellow cedar. I would be inclined to wet it or steam slightly to make it pliable before driving tacks. Best of luck!
 
Alick, how thick is your planking? May just be my eyes however it looks thick where the edges are visible. The combination of being flat sawn, dry and thick might be causing it to split from the hammer blows? Doesn’t look to be countersinking much either, but then again I can’t claim any familiarity with yellow cedar. I would be inclined to wet it or steam slightly to make it pliable before driving tacks. Best of luck!
Hi Andre
Thank you for your reply.
The planking is just under 4mm thick (I sliced some more today in readiness).When I fitted the parts that have split months ago, I did swab them with a lot of boiling water and also found the use of an iron made them more flexible but then when I drove the tacks (or in some cases afterwards) the splits appeared.
I think I will attempt steaming it or maybe even boiling it.
 
I wouldnt boil, as long as the wood is wet. I'm not at all familiar with the grain structure of yellow cedar, so perhaps someone on the West Coast can weigh in, but it really seems like flat sawn lumber and the tacks are not burying in the wood at all. I'd guess the problem lies with the material and not your efforts. Not much help im afraid....
 
I have no experience with yellow cedar, but if it's flat sawn, and it were me, I'd remove all of it.
My experience is flat will buckle in time.
 
I wouldnt boil, as long as the wood is wet. I'm not at all familiar with the grain structure of yellow cedar, so perhaps someone on the West Coast can weigh in, but it really seems like flat sawn lumber and the tacks are not burying in the wood at all. I'd guess the problem lies with the material and not your efforts. Not much help im afraid....
Thanks Andre
There aren't many flat sawn planks.I steamed some short pieces and did the repairs today which worked fine.
I did notice alarmingly some of the planks have come away from the ribs.
I do find in some places the hammer does seem to bounce as it feels like the rib is not tight up against the jig and metal behind which prevents the tacks going home completely.I am hoping I will be able to sort this out with my clinching iron once I have it off the jig??
The whole thing looked very dry so i gave it a wash with water at the end of the day.
 
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