Alan's MachineWorks Snap Flask

Tapered Snap Flask Patterns

Starting a new tapered snap flask to help with double sided pattern plates. The flask has 4 degrees of taper on each side. It will be cast from aluminum. It will use two pins at each end to help draw the pattern plate smoothly from the mold. At opposite corners the flask will have latch mechanisms so the flask can spring open (about 1/4") to allow quick removal of the flask. The taper will allow you to remove the flask and slip on a steel pour jacket. The pour jackets are much cheaper than flasks to build. They tend to help prevent runout between the cope and the drag layers of the mold. The non-latched corners will be bolted together solidly. I am currently have patterns for 10" and 12" sides. These will allow me to build 10x10, 10x12, and 12x12 flasks. I have started 8", 14", and 18" sides but I am not going to complete them until I have all of the rest of the pieces for the flask done. There are 4 patterns for the latches and there are 3 patterns for the (2 pin) pin guides.

Outside of flask cope and drag (10")

Inside of flask cope and drag (10")

Prototype Flask Shell

The next step is to make the follow boards for each pattern piece so that I can mount the patterns on a double sided pattern plate. I will create a mold from castable urethane that allows me to cast the pattern sides directly on the matchplate.

Here are some of the patterns for my new tapered snap flask. The top pattern is the pin guide support for the cope. The pattern just below it will be bolted to the support to hold the cope in alignment with the pins. The two bottom patterns will form the latch/release mechanism for the snap flask.

Here are a couple completed pin assemblies and the pattern from which they were cast. They fit a 5 degree tapered flask and mount on the drag.

Here the pins and guide support have been mounted on a tapered flask. The pin guides have not yet been mounted to the guide support bracket. The same type of pin guides that mount on the flask also mount on the pattern plates to facilitate easy withdrawal of the pattern. Of course using a vibrater on the pattern plate helps too.

Here is a close up of the completed guides. Note the pin guides are adjustable.

The flask is nearing completion. Just have to finish the corner releases and varnish the flask.

Last Modified 12/14/06 09:27