Hi all:

Normally you would see me over in the figures forum, but I have a scratchbuilding question tonight.

I broke both headlight guards on my Academy Stuart Honey. So now I want to make my own with thin sheet styrene.

My question is, how do I get it to hold a curved shape? I know if I make the strip and glue both ends down to the fender it will naturally form an arch, but I fear that there would be tension on the ends and they would easily snap off. So what can I do to bend them into a permanent curve before I glue them on?

Any help would be greatly appreciated!

Thanks all!

John

John,
I use heat mostly from my cigarette. The trick is not to get the plastic to closr to the heat source. I'm sure you can use a candle, hold it above the flame a few inches. You can also try holding it under hot water, form your shape the put it under cold water to capture it's shape.

The big question is whether or not the guard has to extend staright downward after the curve . That makes it a little trickier. When I use plastic for something like this, which is rare now, I find an object with the appropriate curve (sometimes smaller because the plastic likes to spring back) and clamp the plastic around it. For complex shapes you may have to combine objects. Then I immerse it boiling water momentarily. This works well, as seen in these photos of the rings arund the turret bases, but...


...I find brass strip to be a much better alternative now. Before Eduard finally came out with photo etch for the M47 I scratchbuilt all of the brushguards from scratch with brass, and it is infinitely easier than with styrene.

find a brass or copper pipe the right size of the curve. Tie your plastic arround it with wire or similar then boil the kettle. Let the water cool for 2 minutes then place your pipe into a container and cover with hot water. Allow this to cool for a couple of hours and then undo your plastic from the pipe. It will hold it's shape.

I find it better to use metal (brass aluminium copper etc tube as when the hot water heats it it heats the plastic you wish to form from the inside as well.

cheers
Cliff

PS> while a candle or other flame heat source will work it is far harder to obtain just the right amount of heat then with using hot water

I agree with the others in mentioning strip brass. It is soo easy to use once you have the right scale thickness...
Brad

Gee so much work for something so simple.....
I simply roll it on a rubber mat with a mandrel. A steel drill bit will work just as well, as will a pad made from several layer of paper towel folded several times, and taped together. The thicker the pad, or rubber mat the more it will curve. Also, curve it a little tighter than needed, it will flex out to the size you need. (also works for those pesky photo etched MG barrels)
The smaller the mandrel, the tighter it will curve, start learger, and work down to size, radius you need.
I do .005, .10, .20 all the time.

One alternative, although it may not be the cheapest option is to acquire a heat gun. Mostly used in arts and craft type activities but my missus so happens to have one which i ended up using for modelling.

Heat guns are great, they concentrate heat in a wider area compared to a candle. This way, the plastic bends over a wider region as oppose to a small area.

I've used either heat guns or hair dryers and wooden dowel rods{or brass tubing} to form over...use a test lead alligator clamp to hold the loose ends and heat it up till it starts to change texture{glosses over}. The water thing is fine but too much involved for my liking. my two cents...