I started by making pattern for my sand casting using 20mm MDF. First I drew the shape of the handle making a few corrections along the way. After the drawing was done I used my drill with a core bit and jig saw to cut the handle shape. I used a wood chisel to shape and round the grabbing part for the fingers. Last I gave it a good sanding and used acrylic paint over it.
After I opened the flask and the mould was ready I removed the pattern and cut it into 4 parts clamping it back to create the inner handle core parts. The reason I cut it is to get good quality sand casting. It is impossible to press the sand out of the pattern without breaking it if the pattern is in one part.I released the clamps and carefully took the pattern out. Now I have the two inner core parts. I placed them in the correct place in the flask and after close the flask tight with large clamps.
In this casting I tried something new using two tin cans as a sprue and riser extensions. The cans are filled with petrobond and the cavity I made is bigger then the flasks sprue and riser. I was looked after pouring the molten metal and it worked very well. I could see the riser feeding the molten aluminum into the mould, really cool. See picture below of the riser extension.
I cut the sprue and riser with my hack saw and used a metal file to chip off the extra aluminum, then I drilled a hole for the rope and used an electric sander with different sand paper grades. After the sanding part I used fine metal wool for the final polish. To get an even better polish results it could be done with aluminum polishing products and a buffing wheel.
The rope fits very well into the handle hole and the handle is very comfortable for grabbing. The handle is heavy enough to be used as a weight in case it has to be thrown.
