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We have designed three different lever systems with the current design presented here. (Please label the figure and what you are showing in each.)**Harry can you work on this section? Label components and describe each item in detail. Actually, I think we have an update version that shows the eye-bolts. Let me know when you are working on this and I will email it to you.
There are a number of constraints in the design of this lever arm. First, we need to facilitate a way to attach the floats and counter-weight. Secondly, we must have a way to adjust the distance the orifice travels down the arm. It was also requested that the operators be given a means to manually "shut off" the flow. This can be accomplished by moving the orifice directly in line with the pivot. We have also attempted to accommodate a second slide to facilitate attaching a second dosing pH control system. It is preferred that both slides operate on the same side of the lever to allow the operator easier access.
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80/20 Inc. is a manufacturer of modular aluminum framing system. 80/20 components are used extensively throughout our lab and specifically in this project. This section provides some details to assist getting started with these components and using them in design.
http://www.8020.net/ 
; This is the main web page for this company. Available is a complete on-line catalog, price catalog and design ideas. Design is made easier using their "Auto-cad Plug-In." All components and frames are available with this Plug-In making requiring only limited Auto-cad knowledge for a professional looking design.
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