curving metal?????

Steve,

Unless you're prepared to pay for a special tool to roll the metal the best way I've found is to get some dowel rod (or a rolling pin) and roll this back and forth on the aluminium on a softish surface such as a folder towel. Make sure you keep the rolling pin square to the work piece (otherwise you end up with a cone) and work the edges twice as much as the middle as it has a tendency to flatten out and only be curved in the centre. It does work, believe me. Cheap, simple and effective. What more could you ask for. I understand young women in Cuba roll cigars in a roughly similar manner except that the "softish surface" they use is their thighs :-)

According to a book I have on working sheet metal (for auto bodies), curves can be done by making a series of straight bends using a bending brake (a vise of sufficient length will also work), then planishing the metal afterwards. Planishing is softening the bends by working the creases with light taps of the hammer, then finishing with a file (if necessary), sandpaper, and filler for the low spots.

Alternatively (and I haven't tried this), you could carve up a die in wood, fasten one edge of the metal to the wood, then work the metal over the curve with a light hammer and light taps, sort of planishing as you go.

Thanks folks

I am not against spending some money on good tools, though think the rolling pin principle may be the way to go

Thanks again

Steve

Something completely different to think about for carriage roof material; saw one bloke at the recent Gold Coast model train show who used plastic pipe as carriage roof material. Select desired diameter and cut to suit. He was modelling in Sn3.5 so they were on HO track.

Cheers Peter Cokley

Hi Pete

Had thought of that as an option but now have all this Venetian blind stuff hanging around

:)

and it is VERY close to the correct diameter for the application - I just wanted to get it 100%.

Pipe would be a bugger to cut too I reckon

Steve

Will bending it around a rod/pipe smaller in diameter than the roof work? Kinda like styrene. I'm thinking by using a smaller diameter rod/pipe, the metal will be reshaped, but spring back to a smaller than original diamter. ie just enough to curve it just a bit tighter.

Brendan

Saw this this morning while browsing

Re: curled edges from cutting with scissors. Have you tried using a sharp utility knife - like a box cutter - for cutting the metal? Unless it is a very hard alloy of aluminium, you can cut very easily with a sharp knife. It will leave a slight burr on the edge but that is easily removed with a file.

Dale Gloer

m> Hi again all

Hell, I've been using this stuff for years. To cut it, just score and snap - like styrene sheet. To bend it, I pull it around the (round)leg of the chair: don't worry about over-bending it, as it is very easy to flatten it a little.

Cheers

Allan Lees

m> Hi again all

One bad thing about the venetion blind material is that it is hardened aluminum material and this makes it hard to change the bend. To relieve the hardening in aluminum, you heat it above a certain point and let it cool. Cooling in water won't affect the hardening like it does with steel so you can cool it in some water if desired. The gas stove will be hot enough to do the job. As to putting in a different curve, there are a lot of different methods and I'd tend to try a hardwood form with leather or a thin layer of rubber over it. A concave form will be better as you will then hide the marks from a hammer without any troubles. The hammer should be a chunck of the hardwood and the end formed to the shape you desire so as to spread the force widely across the aluminum. The three roll method can easily be made if so desired but you will have to support the middle of the rolls with rollers so that the force will be even across the roll as you are going to be useing long rolls. Three rods with the venter one being adjustable and nice ball bearings on the ends to cut the forces needed to roll the material through can easily be made with mostly hand tools (although a mill will make the job very simple) is what is needed in this case. Personally, I'd make the roofs with styrene as that stuff can be easily bent on the model and glued in place with no problems.

-- Why do penguins walk so far to get to their nesting grounds?