Removing sponsons 1937 CS grade model HW

[thechief]

I have done some searching and couldn't find an answer.
I have started methodically disassembling a 1937 CS ,HW Old Town with original sponsons. This canoe is in perfect condition it has never been apart it had so many layers of crackled paint I decided to do this right. I carefully removed all the canvas trimming closely around the sponsons. Ive taken all the screws from from the inside out and the screws at each end of the solid pieces of the sponson on the outside ,removed all the tacks the only canvas remaining is the 2 layers of canvas in between the sponsons and the planking .I'm able to incert my thin pry bar but there seems to be hidden tacks or screws that won't let me remove the sponson.I'm doing one at a time taking tons of photos. I just quit for the day before I damaged anything.I suppose I have a use a hack saw the type with a single handle that allows me to put the blade in between the 2 layers of canvas to cut whatever is still holding it on. Is this normal? I can't see anything hindering me from separating the sponsons from the canoe on the inside. Anybody have suggestions how to get theses darn things off properly? All is going smoothly otherwise. Not one broken or cracked piece, yet!

 

[Dave Osborn]

So far so good, Chief.... if you take them apart methodically and see how they were attached and canvassed, it’s a lot easier to put them back on.
That said....yes, hidden nails and or screws. I’ve used a stiff putty knife that is sharpened and a good rap from a hammer to shear off the hidden fasteners. A hacksaw blade would probably work too.

 

[thechief]

Thanks Dave, since I can slide my thin pry bar all the way through top to bottom in most every spot except where I hit a nail or tack I thought id eventually wiggle the sponson off. I don't see anymore screws unless they are counter sunk. And the width would prohibit any clinched tacks.I think your recommendation using a sharpened putty knife is what I'll do. I just needed a little encouragement that I was on track. I must say they weren't fooling around attaching those things. I'm sure I'll be back once I get to the canvassing stage. thanks Hank

 

[Gil Cramer]

There are two hidden screws in each cedar end block. One is within an inch of the top and the other is under the second longitudinal strip from the bottom. The strips are difficult to loosen because of the steel nails. Loosen the strips carefully and the screws can be removed. The top screw is especially difficult. There are also nails at the bottom of the sponson at each station . These nails attach the cedar strip to the cedar frame and because of their length some extend into the canoe planking. They will pry off easily.

 

[thechief]

Thank you Gill, all went well except there were 2 screws coundersunk into each end of the sponson frams,aclobg with couple wire nails and 1 clenched tack here and there. being a perfectionist I'm concerned as to where theses screws pulled out of their holes in the rib an d planking. No damage anywhere only worried these screws will not get grip to tighten them down.
Also missed 1 of the screws attaching the center of the sponson to the canoe didn't comment out so nicely. Nothing really when the screws was forced out it slightly pulled out the end the 2 planks that meet behind that rib.I think I can clinch in.There is a small short crack in one end of one of the plank inside. A Small sliver of horizoal piece popped out . Small enough it can be glued in. This will be covered anyway by the sponson .Is the a patching material I could use to completly smooth this area or am I taking this all to far the boat Is in wonderful original condition for being over 80 years old. Both my canoes never left this lake. Ive got the history old town provided. Thx