George Lendich wrote:

Paul,
As promised an update on the progress of the bellhousing.

As I intend to use this mock-up to make a mould (Plug) I've laid it on

a

piece of plastic covered board and sealed around the bottom edge with a
concave bead

of water based filler and will allow it to dry thoroughly.

I've already waxed the mock-up but will give it another coat before I

apply two coats of PVA Mould release.

I've purchased the glass and Core-Mat (5mm) and will lay it up as soon

as

all is ready.

George (down under)

Looks good George. I'll have a look around LA and see if we can get it

cast

in magnesium as 5 mm .196 inches wall will be a bit heavy in aluminum.

Paul Lamar


That may be a tough mold to pull due to its shape. It is amazing how

much

force a couple of square feet can have when attached with wax and PVA.

Are

you planning on using a water-pressure release fitting in a non-critical
area (such as the center that will be cut out)?

Scott Gettings

Scott,
Your so right there Scott, I had a hell of a problem getting the last one
off - had to cut out the mock-up. As it was only made of plaster it wasn't a
problem, this one is timber.

I will use your timely suggestion mate- will household water pressure do the
job?
George (down under)

George,

As long as you have a coat of PVA on the plug, the water should dissolve it enough to get a release with minimal pressure.  So you should be fine with
municipal pressure.  As long as you have the fitting(s) in place, you can always add more pressure if needed.  Large or complex molds (e.g. boat hulls) often
use numerous fittings.

Scott Gettings

 
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