This print is aimed to hold open the hood of a custom salt spray chamber in Michigan Technological Universities M&M building. This was developed to reduce the safety risk of current proping methods. Although created for a specific piece of equipment, this can be used to prop open any hood that it can fit on. Currently no comperable commercial equivalent exists to my knowledge. What this part may not save in monetary costs, the added safety benifits are priceless. A full set of printed parts will use 200 - 400 grams of plastic based on infil. Based on an infil of 50% and a filament price of $29/kg, a full set of printed parts would cost about $7.80. At current prices on McMaster, cotterpins would cost a total of $2.30, and bolts and nuts would cost $3.50. This gives a final cost of the complete system of $13.60. Alternatively, you can use small pieces of 1.75mm filament to replace the cotterpins, resulting in a total cost of $11.30. The cotter pins will only provide a cleaner ending look.

 

Assembly Instructions:

 

1) Print/obtain the following parts:

x2 - Top Bracket

x2 - Mid Bracket

x2 - Bottom Bracket

x2 - Short Shaft

x2 - Long Shaft

x4 - Joint A

x4 - Joint B

x8 - Cotterpins - McMaster Part#: 92375A100

x8 - 1/4"-20 X 3/4" Stainless Steel bolts w/corresponding nuts

 

2) You will need two complete assemblies. Assemble the parts as shown in the Full Assembly STL, and again as a mirror image of the Full Assembly STL. Use the cotterpins to secure the Joint parts in place. 

 

3) Line up the completed assemblies to the hood and mark where mounting holes must be drilled. Drill 1/4" through holes in these locations. 

 

4) Using a sealing adhesive on the mounting surfaces, and secure with the 1/4"X3/4" Bolts

 

5) Allow sealing adhesive to cure prior to using salt spray chamber.

 

A sketch of the system was made in AutoCAD to develop the required dimensions, all modeling was done in OpenSCAD

 

Designed and modeled by Kyle Barie

 

Made for MTU MY4777