large profile guage required (1m+)

[yourmomm]

anyone know where i can get a large profile guage (1m+)? failing that, a way to accurately transcribe the curve of my deck, to make a jig around which i can steam new hardwood gunwhales? before you ask, i cant trace out the profile of the old gunwhale, due to it having completely disintegrated due to a nasty combination of rot and fire....many thanks ryan

 

[PaulJS]

Could you use some sort of pantograph arrangement made from wooden slats? Just make sure that the arms are the same length!

 

[Poignard]

I would use a spiling board. Mount a piece of plank, or some rigid sheet material, alongside where you want to find the curve. [after roughly trimming it to the shape required] then take a stick and place it on the plank so that one end is touching he curved part of the boat, draw a line around the stick on the plank. Repeat this in as many places as needed.

Remove your spiling board and lay it on the material you are using for the jig. using the same stick, place it in each of the outlines you drew and mark where its outer end falls. Repeat for all the places you marked and you will have the curve you need. Screw blocks of wood to the jig along the curve and bend your steamed timber around them.


It's easier to see how this works with a picture, which you should find in any boatbuilding book. Or have look at this webpage

 

[Robin2]

If the shape of the deck is sound, a couple of corn-flake boxes may be ideal to use for a template. Well, have 3 to hand in case you make a mistake ! The family don't need the box and CAN eat the cornflakes from the plastic bag for a week.

However, if the shape of the deck is lost due to rot etc I suggest making a better quality template i.e. "pseudo" deck from thin timber - plywood or hardboard - because this will allow you to judge whether it is "right" before committing yourself. When finished the pseudo deck only needs to be OK on the outside edge, which means you can hack away at it until the sheet has been reduced to a width of a foot if necessary!

Maybe one side of the deck is OK and the other side is damaged - then make the template from the good side (measured to the centre of the deck) and turn it upside down for the damaged side.

 

[john_morris_uk]

Its unusual to have to steam gunwales. Unless the curve is very pronounced or you have some sort of canoe stern lots of gunwales are simply pulled into place and fastened, or perhaps a little steam is applied to the areas of maximum curvature.

If you want to make a pattern of a large curve the normal method is to use a pointed batten and an old bit of hardboard. The batten is a spiling batten and you can define and repeat any shape with a bit of care. The method has been described before on these forums and a search should find a description.

 

[yourmomm]

yes john morris-traditional canoe-stern it is!!! i would really like to add a picture to my profile but have no idea how to....not very clear but a picture of her can be seen here

 

[john_morris_uk]

You mean it looks like this: (Right click on the image in facebook and copy the properties to the pop-up box 'image' in the instant mark up options below your YBW editing screen.)

A little steam on the timber at the point of maximum curve will suit. Is the boat in the water or on the hard at the moment?

 

[Forbsie]

What you need is a Tick Stick.

I was just talking about them last night in the pub. There was an article about them in the Jan/Feb issue of Wooden Boat.

 

[Sixpence]

Forbsie, I hate you /forums/images/graemlins/grin.gif I could have done with reading that a couple of weeks ago, not now /forums/images/graemlins/blush.gif
Call me and I'll forward pics. of my Debutante for your perusal, PM if you've lost my number /forums/images/graemlins/cool.gif

 

[yourmomm]

thanks all-tick sticks and spiling boards look useful-and thanks for advice john morris tho im a complete luddite and a little baffled... /forums/images/graemlins/confused.gif the boat is in the water-spent all day today trying to remove epoxied screws from the (epoxied) strakes in a tender tied to the boat's hull-very precarious...and more than the odd expletive as tools were dropped into the murky marina depths...giunwhales are made of epoxy-sheathed marine ply and rotted through-deck seam sound though-will be replacing with mahogany!! cheers ryan