Fabrication of a Conductivity Sensor ENGR 121 living with the lab

2 The content of this presentation is for informational purposes only and is intended only for students attending Louisiana Tech University. The author of this information does not make any claims as to the validity or accuracy of the information or methods presented. Any procedures demonstrated here are potentially dangerous and could result in injury or damage. Louisiana Tech University and the State of Louisiana, their officers, employees, agents or volunteers, are not liable or responsible for any injuries, illness, damage or losses which may result from your using the materials or ideas, or from your performing the experiments or procedures depicted in this presentation. If you do not agree, then do not view this content. The copyright label, the Louisiana Tech logo, and the “living with the lab” identifier should not be removed from this presentation. You may modify this work for your own purposes as long as attribution is clearly provided. DISCLAIMER & USAGE living with the lab

Examples of Conductivity Sensors living with the lab 3

Raw Materials Ultra High Molecular Weight Polyethylene white = hydrogen red = carbon Chain molecules align more than for lower density polyethylene (packed together more tightly) SOURCE: Phone order from Also known as... poor-man’s teflon Type 316 stainless steel rod or wire approximately 1/16 inch diameter $0.46 per foot Ultra high molecular weight polyethylene inch diameter bar $1.74 per foot living with the lab 4

Parts and Materials living with the lab 5

Lathe You must become familiar with the operation and safety procedures of the tools before beginning the project. tailstock Q bit for center drilling workpiece tailstock quick release crank handle to feed drill bit from tailstock spindle and chuck crank handle to move cross slide crank handle to move the carriage key for chuck carriage cutting tool living with the lab 6

Safety Shield: Do not start machine if this shield is not in place. emergency stop (hit this button to quickly stop machine) Spindle Speed Control: This will be preset for you, so don’t adjust. Lathe: Safety Features and Operation With the safety shield closed and your safety glasses on, practice turning the machine on and off (turn off with both the off button and the emergency stop). Practice moving the carriage, cross-slide and drill bit in the tailstock. red off button green on button forward (for drilling and facing) and reverse (for beveling) living with the lab 7

Milling Machine: Loading Workpiece into Chuck Make sure the workpiece is securely clamped in the vise before beginning work. living with the lab Download “2_cond_a_loading_workpiece.wmv” video. Store video in the same directory as this presentation. Click on the picture to play video. 8

Lathe – Watch Out for Rotating Parts living with the lab Download “2_cond_b_rotating_parts.wmv” video. Store video in the same directory as this presentation. Click on the picture to play video. 9

chuck workpiece tool Safety Checklist: 1. Avoid contact of tool with chuck 2. Keep hands, hair, clothing, and jewelry away from rotating parts 3. You should feel it when the drill bits drills through the far end of the workpiece (only advance tool slightly past this point) 4. Are your safety glasses on? living with the lab 10

Safety Rules for Freshman Labs 1.Do not operate any machine unless you have completed a hold harmless form been trained to operate the machine been authorized to do so by the instructor or lab monitor 2.When using rotating equipment such as milling machines, drills and lathes, securely tie long hair back to remove the possibility of it falling below your face do not wear loose clothing remove lanyards or jewelry hanging from your neck or wrist 3.When using power tools like milling machines, drills and lathes, clamp the workpiece in a vise or chuck before drilling or cutting never hold or restrain the workpiece with your hand make sure all safety guards are closed before powering up machine never leave a running tool unattended 4.When working in the lab, always wear approved eye protection take common sense precautions & avoid “horse play” keep work area clean & organized never use your own power tools only use lab facilities to complete activities required for ENGR 120, 121 and 122 report damaged equipment, unsafe activities and accidents to the instructor Do not begin to fabricate your pump until you have carefully read the operating and safety instructions above and agree to operate the equipment in a responsible manner. You must sign the safety contract before beginning fabrication. living with the lab 11

Positioning for Facing living with the lab Download “2_cond_c_positioning_for_facing.wmv” video. Store video in the same directory as this presentation. Click on the picture to play video. 12

living with the lab Facing and Beveling Download “2_cond_d_facing_and_beveling.wmv” video. Store video in the same directory as this presentation. Click on the picture to play video. 13

living with the lab Center Drilling Download “2_cond_e_center_drilling.wmv” video. Store video in the same directory as this presentation. Click on the picture to play video. 14

Create Threads in Each End using 1/8 NPT Tap living with the lab 15

Mark Locations for Conductivity Probes center mark ½ inch location for inserting probes living with the lab 16

Drill Holes for the Probes living with the lab 1) Rest the ends of the workpiece on the parallels (different parallels may be used) 2) Use a #53 drill bit (0.059 inch diameter) so the inch SS rod will be press fit into the hole 3) Drill inches deep (this is 1/8 of an inch shy of going all the way through) 17

Cut 1/16 inch Stainless Steel Rod (already done for you) living with the lab 18

Press the Rods into the Holes This is a little tricky. Go slow and keep the rod in place with one hand while slowly tightening with the other. living with the lab 19

Press Terminals onto SS Rods using Vise (or tap on with hammer) living with the lab 20

Crimp Terminals onto Stainless Rods living with the lab 21

Crimp 20-inch Piece of 22-Gauge Wire onto Terminal Be sure to strip the ends of the wire before crimping living with the lab 22 CONGRATULATIONS – You’re Done!!!!