You will need a large or medium exam glove, rubber band, a bag penetrator flutter valve fitting, and valve deflector.
Cut one of the longest fingers from glove. Select one that is free of wrinkling and creasing near its tip. If the tip has severe creasing or wrinkles, the valve will never shut properly. 2nd pict shows the badly wrinkled end.
A non-wrinkled end, thinner glove material, and longer finger create a more effective valve.
See video https://youtu.be/FL7E_8VEMfE for additional explanation about flutter valve function.
Cut one of the longest fingers from glove. Stretch its open end over flutter valve fitting. Note the glove finger has a natural flatness. Align flatness of glove finger with long axis of valve ellipse.
Ensure glove finger is advanced past the groove. Secure with a rubber band in the groove.
Cut off part of rounded tip of glove finger. The size of cut should be between 10 and 15 mm long. Smaller yields more pressure but less flow. Too large a cut and pressure will be too low. If finger is cut properly, its end should naturally be flat and nearly closed in absence of airflow.
Valving action is not intended as the primary inflow protection. Continuous positive pressure is the main protection, but valving is important in case user takes a very large, forceful inspiration and greatly deflates bag.
Your contributions are licensed under the open source Creative Commons license.
Insert a new line below
Insert a new line above
Indent current line
Unindent current line
Delete current line
Navigate to next step.
Navigate to previous step.