Arched cuts, how does everyone do them?

[bread519]

So I've been hunting around, and can't find a definitive answer. How does one measure and cut the arched shape of the bus ceiling for a wall? I've seen a few methods, but can't find instructions on how to measure for the cut.

Someone on here, I can't remember who, used a piece of cardboard as a "stencil", this is what I'm leaning towards so far because I'm not a very skilled carpenter. But idk where to find such a big piece of cardboard

[milkmania]

Originally Posted by bread519

So I've been hunting around, and can't find a definitive answer. How does one measure and cut the arched shape of the bus ceiling for a wall? I've seen a few methods, but can't find instructions on how to measure for the cut.

Someone on here, I can't remember who, used a piece of cardboard as a "stencil", this is what I'm leaning towards so far because I'm not a very skilled carpenter. But idk where to find such a big piece of cardboard

I've heard a bow & string will help too...
Haven't tried either, YET


Someone should post up a "to scale" pdf that'll get ya close

[BusFiend]

Behind the big-box stores that sell appliances, you will find a plethora of cardboard in various sizes. Asking inside the store will normally nab you all you need.

The radius doesn't have to be perfect, just close. Use flex trim to clean the look up.

[EastCoastCB]

Originally Posted by BusFiend

Behind the big-box stores that sell appliances, you will find a plethora of cardboard in various sizes. Asking inside the store will normally nab you all you need.

The radius doesn't have to be perfect, just close. Use flex trim to clean the look up.

That's what I've been thinking, when the time comes.

[roach711]

I used a pencil and some cardboard to scribe my curved cuts.

First, tape a pencil to a block of wood. The wood spaces the pencil out from the surface and gives you a better grip on the pencil. Then cut a piece of cardboard to the rough shape of the curve. You want your cut imperfections to be less than the thickness of the pencil/wood marker thingy. Then hold the cardboard up to the surface (wall, ceiling, whatever), hold the marker up to the surface with the wood block against the surface, then scribe the line keeping the wood block flat against the surface.

Now cut out your cardboard template and use it to transfer the shape. A belt sander is useful for touching up your curves.

[milkmania]

My air door box (that I'm going to pull down and build a shelf/bin in) already has my curves that I'll transfer to graph paper. I'll post a copy of graph here

[juliol]

Originally Posted by roach711

I used a pencil and some cardboard to scribe my curved cuts.

First, tape a pencil to a block of wood. The wood spaces the pencil out from the surface and gives you a better grip on the pencil. Then cut a piece of cardboard to the rough shape of the curve. You want your cut imperfections to be less than the thickness of the pencil/wood marker thingy. Then hold the cardboard up to the surface (wall, ceiling, whatever), hold the marker up to the surface with the wood block against the surface, then scribe the line keeping the wood block flat against the surface.

Now cut out your cardboard template and use it to transfer the shape. A belt sander is useful for touching up your curves.

My friend, you are a genius.

J

[Alan N]

Originally Posted by roach711

I used a pencil and some cardboard to scribe my curved cuts.

First, tape a pencil to a block of wood. The wood spaces the pencil out from the surface and gives you a better grip on the pencil. Then cut a piece of cardboard to the rough shape of the curve. You want your cut imperfections to be less than the thickness of the pencil/wood marker thingy. Then hold the cardboard up to the surface (wall, ceiling, whatever), hold the marker up to the surface with the wood block against the surface, then scribe the line keeping the wood block flat against the surface.

Now cut out your cardboard template and use it to transfer the shape. A belt sander is useful for touching up your curves.

Excellent idea!
Much better than the trial and error method I used.

[roach711]

Originally Posted by juliol

My friend, you are a genius.

J

Thanx! I wish I could take credit for the idea, but it's a carpenter trick from way back.

[Scooternj]

There are a slew of boatbuilding tools I've seen. But I kept the inside front cap as a rough template for all my arcs.

[Cabinbus]

this is the best method make sure the cardboard stays square

[cheryl_ann44]

This is link from vonslatt--he used the poster board/marker method showing how to get all the little dips and dings. He has other really good ideas--I especially like reversing the windows which I am going to try on my bus.
School Bus Conversion - Framing the Bus

[somewhereinusa]

Originally Posted by cheryl_ann44

This is link from vonslatt--he used the poster board/marker method showing how to get all the little dips and dings. He has other really good ideas--I especially like reversing the windows which I am going to try on my bus.
School Bus Conversion - Framing the Bus

That's way to complicated, roaches suggestion works well, I just use a large magic marker on it's side.

[RHOMBUS]

I'll be tracing the upper rear panel that I have removed:

[somewhereinusa]

Before you cut your panels, you might want to make sure the curve is the same. On mine the curve is different in different locations, even from side to side.

[roach711]

Another method is to cut the bus in half at the spot you want to match, hold your board up to the cut edge, trace the curve directly, then weld the bus back together. This method gives an extremely accurate match.

[Jolly Roger]

I went with the cardboard template option and made the template for my biggest/widest wall first and after that I was able to cut a smaller section out of it to match my overhead bin pieces and tape it back in or remove it as needed.
My full height walls were a little tricky until I got my template right.
My outside walls lean out a little to the bottom of the windows and then lean back in a little bit more than they leaned out up to the busway/cable tray/wire run molding and then the curved ceiling. So a full length template got me started but ended up only needing the top piece from midway of the windows up.

[Tango]

You guys all have it SO easy, what with flat walls and all. My '46 is all curves. The sidewalls flare out from the floor about an inch at the window bottoms then back in at the top. Also makes fitting a door a real nightmare. And the rear quarters...they are all compound curves. I need to get with an old school wooden boat builder to figure those out!

Or maybe a cooper (wooden barrel maker).

[family wagon]

Keep in mind when tracing with a spacer like the block of wood that if you're copying anything but a straight line, then you're actually going to get a reduced copy. Envision using the spacer block to trace inside a circle -- the copied circle, while being a perfect match to the original shape, will be smaller by the thickness of the block plus half the thickness of the pencil/pen/marker.

I like to use the block method until my template is "pretty close" and then remove the block and use the pencil alone, perhaps even held so that the tapered/sharpened tip instead of the whole body runs on the tracing surface. The nearer the line is drawn to the surface you're tracing, the less the shrinking effect will be.

[joeblack5]

nice explanation family wagon. I was going to mention something but could not find the right words. The circle envisioning is excellent.

Later J