First Time Questions "Again"

[Bwing96]

OK I'm new here so be easy guys. I have read the whole thing on Pirogues and really have not seen the answer to these questions I'm about to ask, although I do feel they have probably been answered many times.

1. Is there a reason for not using 3/16" ply to split the difference between those that think you must have 1/4 or those that think 1/8 is sufficient ?
Seems like it would be the best of both worlds (Weight vs Strength)

2. What would be wrong with using the fine saw dust made from cutting plywood for cabinets for wood flour ? I notice under my table saw this is much finer than what you get from oak or pine boards.

3. Lengths for a pirogue seem to be a favorite topic of discussion for many different reasons, but haven't seen anyone talk about using 3 sheets of ply to make 2 pirogues. Butt jointed would make (2) 4'x12' sheets.

Ok flame suit on now let me have it.

 

[JEM]

1. Is there a reason for not using 3/16" ply to split the difference between those that think you must have 1/4 or those that think 1/8 is sufficient ?
Seems like it would be the best of both worlds (Weight vs Strength)

My opinion: Use 1/4" (6mm) if only taping the seams. 3/16" (4mm) if you're applying fiberglass cloth inside and outside the hull.

2. What would be wrong with using the fine saw dust made from cutting plywood for cabinets for wood flour ? I notice under my table saw this is much finer than what you get from oak or pine boards.

Nothing at all. I'd run it through some sort of sieve to filter out any big chunks. Careful it has no oils in it.

3. Lengths for a pirogue seem to be a favorite topic of discussion for many different reasons, but haven't seen anyone talk about using 3 sheets of ply to make 2 pirogues. Butt jointed would make (2) 4'x12' sheets.

I don't follow you on that one. you mean 4' x 16'?

Ok flame suit on now let me have it.

No flaming. We've all wondered many, many, many questions.

 

[Bwing96]

Cut 1 of the 3 sheets in 1/2 so you have 2 pieces 4'x4' and then join one of the 1/2 sheets to a whole sheet, so you wind up with 2 sheets 4x12

 

[Bwing96]

What is the difference in taping and fiberglassing inside and out ?
I think the fiber glassing inside and out is pretty straight forward, I'm not sure I understand about taping though.

 

[Kayak Jack]

Wing,

Others may differ on this, I personally thing that just taping is a quick & dirty way of cutting corners. I dislike it intensely.

Were I making a boat quickly to escape an advancing enemy, I would consider just taping seams. Under those conditions, I may even use an (shudder) aluminum boat. Otherwise, I like to use 4mm and glass it inside and out all along the hull, and outside on the decks.

To me, hull integrity is pretty important. The primary job of any boat is to stay afloat. Anything else it may do is extra.

Others will differ.

 

[Bwing96]

How is taping done ?
Doesit take the place of fiberglass ?
I don't guess I have seen any of this or am I familar with its workings.

 

[Kayak Jack]

Fiberglass tape, say, 3" wide, is epoxied along the seams. It reinforces a seam quite well. It does not reinforce anything else where it is not applied.

I prefer to glass inside and out of the hull, and add reinforcing tape along the keel line where it scrubs on obstacles. I also add tape inside and out all along the shear line where the deck is joined to the hull.

Butt joints, where two pieces of plywood are joined at their respective ends, are often taped on both sides to make a longer plank. Then as they are joined with others along their length to build a hull or deck, glued and glassed again. THIS makes a rugged boat.

A boat that is only taped along the seams requires heavier wood or much lighter use. My personal preference is to avoid those options.

 

[Bwing96]

Is 3 inch wide tape on the seams inside and out strong enough ?

Is 4 inch tape available ? Does Home Depot or Lowes carry the tape or cloth and the right epoxy for this ?

 

[JEM]

Is 3 inch wide tape on the seams inside and out strong enough ?

Is 4 inch tape available ? Does Home Depot or Lowes carry the tape or cloth and the right epoxy for this ?

I can't speak for all Home Depot or Lowes, but I've yet to hear of one that carried the proper materials. I believe Uncle john customers get a discount at www.raka.com .

I'd go with whatever Uncle john recommends on his plans. But fiberglass tape comes in many different widths.

 

[Bwing96]

Thanks for the link.
I'm going to really be brave and only use what's in my mind instead of a plan. Maybe a big mistake but will be a heck of a learning experience.

 

[Bwing96]

Now after looking at the link to RAKA I'm really confused.

How much tape does it take to do a couple of 14' pirogues inside seams and out.
What width and weight is most commonly used ?
How much epoxy does it take per boat and what kind to use ?
How far will a pound of wood flour go? (how many boats)

I'm planning on trying to build a couple of 12' pirogues to start with, using 1/4' ply.

 

[hairymick]

Bwing96,

Welcome to the forum mate.

Your last questions are a bit like asking how long is a piece of string. :lol:
If your boat is 14 feet long, allow about a foot for the curve round the chine and then multiply that by 4.

That is a length of tape for both sides of the chine on both sides of the boat.

60 feet should cover this sides. I would suggest you get more for other little bits you will want to do.

Re the wood flour, Again, how long is a piece etc. etc. It depends entirely on how much you use. I would suggest 2 or 3 pounds just to be on the safe side.

re the sandings and saw dust on your shop floor from cutting ply. When you mix epoxy with it, it will go very dark in colour. Provided it is clean and you have sifted all the course bits out. It should work OK though.

As Matt said, I would very respectfully suggest that you use what Uncle John recommends and build to his plans. They are fine boats as they are .