How tight should canvas be I have wrinkles that aren't going...

[alick burt]

Hello Folks
I am in the process of canvassing and hope you can help me sort a few wrinkles.
I am at the stretching stage having got struts to the ceiling a pair of clamps made with one anchored to the wall by 2 webbing straps and the other one with a single bigger strap to do the pulling.
I have started to tension it and noticed a crease along the keel line at one end that doesn't seem to be going.
It extends from about five feet in back to where the stem begins to curve.

The above picture was taken from underneath with the bow/ stern to the right.

My questions are will it go if I carry on increasing the tension?
Should I try relaxing it all and then go again?
Or am I overthinking it and the tension I apply when fixing it will sort it out?
There are also a number of creases at the other end I am not sure about either that are on the side.
Will tightening it more remove these or should I relax it instead and maybe try again.
Will the tension I apply whilst tacking put this right?

I have currently left it overnight to see if that helps but hope to sort it tomorrow as it is set up across the workshop which makes life awkward Hence the stepladder for climbing over it!

All help gratefully received.

Many Thanks

Alick

 

[MGC]

How much downward pressure are you applying? It is important to stretch in both axis, horizontal and vertical. From my experience more tension is better so I would probably not reduce the pull on it unless you have it so taught that the canoe won't settle into the pocket. I suspect that once you start pulling the canvas to tack it that you will pull these puckers in. Don't forget to use a "cloth's pin" to bring the canvas in tighter to the stems when you start to work you way towards the ends.
For reference here are a few pictures of one I recently canvased. In the first picture it looks a bit like yours. Then I shifted the canoe in the canvas just a bit and applied a bit more downward pressure to get it to the point where I could start stretching and tacking.
Good luck and post after pictures....it should be just fine.

 

[alick burt]

Hi MGC
Thank you for your reply.
I have struts up to the ceiling which has beams made of telegraph poles so they are holding it down.
My thinking is that the wrinkle on the keel line should go if its pulled tight enough by the come along but it seems to be staying put.
I dont want to end up ripping canvas or pulling my fixings out of the walls....
I think at present I will try loosening and retrying tomorrow.
I have my clothes pins at the ready

 

[Andre Cloutier]

Mike, whats that form with the sexy kickup near the ends?

Allick, i canvas upside down all the time and those wrinkles appear. best to use sheet metal vice grips ( when i used to read Classic Bike i think they were called Mole grips lol) and a block of wood to keep from marring the inwales, and as you grip the canvas and roll up and into the boat the canvas will shift and the wrinkles will disappear. keep the tension on and be sure to use clothes pins as Mike says so you can fasten close to the ends until you cut her out. never had a problem. unlike upholsterer's pliers, they are smooth and dont puncture the canvas. one ring at the base of a wall and a vehicle trailer hitch and you are all good to work upside down. give it a try next time!

 

[Fitz]

Here are a couple of tips for what they are worth.

I like the upside down method too.
I only secure the canvas to a point just before the decks before taking it off the stretcher.
Don't be afraid to use a few temporary "cheater" staples to hold the canvas to the hull as you work around the decks. Remove them when it is all done.
Don't be afraid to pull some staples/tacks and readjust/tighten things around the decks.

Cheers,
Fitz

 

[MGC]

Mike, whats that form with the sexy kickup near the ends?

You have a finely calibrated eyeball. Look at my avatar. It holds a clue.
Yes to Fitz recommendation not to worry about retightening if it's necessary. With some hulls it's almost inevitable that you will need to pull a few tacks and do some spot tightening. And Andre is spot on about protecting the rails. I use a piece of cardboard for that.

 

[Dave Osborn]

I’ve fastened a piece of half round wood on the back side of my vise grip stretching pliers. It gives me a fulcrum to push against and does not mark the inwales.

 

[alick burt]

Thank you everybody for your swift replies

I relaxed it and then retensioned before going ahead with my tacking operation. I don't have stretching pliers but I made a suitable device based on the one I saw in Jerry Stelmok's book about Joe Seliga that Joe used. I think it has done the trick despite tearing the canvas a bit at the edges. I still think if I do another one I will get a hide strainer. Good idea, Dave putting a bit of wood on the back too.

I started off using tacks but later on when I started driving the tacks home I noticed they were in danger of splitting the rib tops so I changed to staples. I also found them easier to put in whilst also holding onto my strainer.

I did find a few temporary cheater tacks useful thanks Fitz when it came to making sure the canvas was pulled enough where the crease was along the keel line as they are easy to take out and adjust.
Thank fully I was able to remove the hull and place it back in a position in my workshop where I can move about without having to use the stepladder to get over it.

Thanks again for your helpful replies I will close the ends tomorrow.

Alick

 

[Andre Cloutier]

Look at my avatar. It holds a clue.
Whats an avatar? haha. too small. let me guess Rushton given the old looking heavy galvanizing on the bands.