Final Manufacturing Lab Report: Threaded Hinge Clamp
Matt Worthington & Jean Carlo SotomayorMER-101 Section 2 (Engineering Graphics)Mechanical EngineeringProfessor Glenn P. Sanders
IntroductionThe goal of this project was to manufacture a fully functioning thread-driven, hinge clamp. Over the course of the term we would manufacture one or two parts at a time each week. The manufacturing procedure of each individual part was usually described to us verbally by the professor as well as through diagrams and guides. We learned to use different machines, such as the Milling machine, the band saw, the lathe, and the belt sander. From week to week we became more familiar with the machinery and the process started to flow more smoothly. After several weeks, all the necessary parts to put the clamp together had been manufactured, and it became time to assemble the clamp.Once assembled the clamp proved to be fully functioning. The Clamp is driven by a threaded bolt with a crank shaft through one end. It is composed of four braces (2 of Brace A) and (2 of Brace B) that our structurally held together by two different sized pins (Pin A & Pin B). The clamp opens and closes by turning the crank shaft counterclockwise or clockwise, respectively. The threaded bolt is fixed to one hinge (Hinge B) and turns through the other Hinge (Hinge A) to open and close the clamp. The end on each brace where the braces meet when the clamp closes has a swivel grip on each side to tightly hold the object(s) which are being clamped together.
Brace ATo manufacture Brace (as seen in figure 1) we started with an approximately (6.0x4.0x0.11 inch) metal plate (as seen in figure 2). First we laid the paper blueprint with the to scale representation of the desired product printed on it. After creasing the edges to keep the paper in the same spot, we used the center punch and hammer to mark the center holes on the plate. Next, we used a steel ruler, compass and scribe to make the appropriate arcs around each center-punched hole (as seen in figure 2) to prepare the plate for the proceeding cutting and drilling work. Once the stainless steel plate was ready to be drilled we set it in the vice of the milling machine and started by predrilling all the center-punched holes. Then we proceeded to drill the five inch diameter holes on the brace (as seen in figure 3). We used the same bit to predrill a hole in the center of the fillet arc which we proceeded to drill with a 5/8 inch bit. The digital readout on the machine was very useful and precise and helped make this a more efficient process. After drilling the six collective holes with the appropriate sized bits to achieve the step (seen in figure 3), we then filed all the metal burrs in and around the drill holes. Next, we used the steel rule and the scribe to create and connect arcs of different sizes (seen in Figure 2) with tangent lines and prepare the plate for cutting. Next, we moved on to the band saw in order to cut out the shape we had just outlined (as seen in figure 4). The band saw prevented us from following the curve with utmost precision, so their were several cuts to be made on each rounded end in order to prepare the sheet for a reasonable amount of sanding. The sheet grew hot a couple times due to the friction of the sander on the rather rough edges. After several intervals of precision sanding, interrupted by dunks in the water to cool the sheet down, we ended up with a decent quality finished
(Figure 1)(Figure 2)
This diagram shows the finished brace plate. This diagram shows the plate with the scribed arcs and their radii/location. (Figure 3)(Figure4)
this diagram shows the plate after the holes are drilled this diagram shows the tangent lines connecting the arcs and outlining the figure
Brace BThe process for manufacturing Brace B was almost ientical to that of Brace A but it involved a little less cutting and drilling due to the less complicated nature of the part as seen in (Figure-1). Again we began by using hand-drawing techniques to get a general layout of the drill holes, and created an outline of the part. Once the part was mapped out, a center punch was used to create hole so the drill doesnt slip. With all this complete, we brought our plate to the drill, and used the digital readout to create a hole that is accurate with the dimensions seen in (Figure 1). With the hand drawn holes we could tell whether or not our holes are being drilled in the right spot. After the drilling, it was necessary to smooth down any protruding metal created by the drilling. We then carefully used the band saw to cut out the outline of the part, including the filets. Finalizing the piece by using the electric sander to smooth down any rough edges that were created during the cutting.
Pin A & Pin BBoth Pin A & Pin B started from stock metal cylinders of roughly 1.25 in length and 0.31 in diameter (as seen in figure 2a & 2b). For Pin A we used the Lathe with the digital coordinate readout, while for Pin B we used the lathe with an Analog layout/adjustment knob. The steps for manufacturing the Pins was very similar .For Pin A in, we set the stock piece in the lathe and made 2 cuts to shorten the piece to the required length of 1.13in (as seen in figure 3a & 4a) and zero the x-coordinate of the machine. We then set the diameter rating on the lathe to .25 in (as seen in figure 5a & 6a) and proceeded to cut a .19 in diameter shoulder on the piece. We used a file while the piece was still being turned to dull the edges of the shoulder into a slight chamfer. We then stopped the machine, turned the piece around and repeated the same steps to make an identical cut on the other side (as seen in figure 7a). These steps resulted in a finish product (as seen in figure 1a).The manufacturing of Pin B was slightly less efficient due to the analog position/diameter readout, but the process was rather Identical. Again we set the stock piece in the lathe and made 2 cuts to shorten the piece to the required length, this time of 0.875 in (as seen in figure 3b & 4b) and zero the x-coordinate of the machine. We then set the diameter rating on the lathe to .25 in (as seen in figure 5b & 6b) and proceeded to cut a .188 in diameter shoulder on the piece. We used a file while the piece was still being turned to dull the edges of the shoulder into a slight chamfer. We then stopped the machine, turned the piece around and repeated the same steps to make an identical cut on the other side (as seen in figure 7b). These steps resulted in a finish product (as seen in figure 1b).
Pin A Process
Figure 1aFigure 2aFigure 3a
Figure 4aFigure 6aFigure 5a
Pin B Process
Figure 2bFigure 1bFigure 3bFigure 4bFigure 7bFigure 6bFigure 5b
Hing A & Hinge BHinge A & Hinge B (as seen in figures 1A & 1B) were manufactured one by each lab partner. For Hinge A, we were given a stock cylindrical steel piece of about 1.01 inches in height and 0.75 inches in diameter. This piece was already cut to size so there was no need to make a zero-cut using the lathe. Upon setting the piece in the Lathe, two rough cuts of approximately 0.27 inches in diameter were made with application of some oil lubricant (about half the distance of the desired length each time). The final cut was made by setting the diameter to 0.25 inches and running it along the face until the desired 0.125 inch shoulder length was arrived at. The edges of the piece were then filed down, the part was flipped around and the above process was repeated to arrive at a symmetrical part with the appearance and dimensions of (figure-1). The part was then placed in the milling machine, which was pre-zeroed, to center-drill and then drill a 5/16 diameter hole in the center body of the hinge. The hand tapping machine was then used to thread the hole by first correctly positioning the part in the vice using the guide accessory and then using the tapper to thread the hole. It became clear the importance of using the guide accessory first to make sure the part is lined up perfectly, when after the initial threads were a little tight and the part was put back into the tapping machine, the guiding tool was neglected to be used and the structural integrity of the part was nearly sacrificed. Adjusting the position to the original tapping and running it through again managed to take care of this problem and resulted in the finished product (as seen in Figure 1B).A nearly identical process was undertaken for Hinge B to arrive at a part with dimensions seen in (Figure 2B). The difference, aside from the dimensions, was that the hole was not threaded in this piece, but rather it was center-bored using the milling machine and as seen in (Figure-2B). But the flat edge as seen in this same figure was created using the milling machine. The milling machine was pre-set to make a flat swipe cut across the surface. Overall this laboratory was rather straightforward and routine, and each student was only responsible for one hinge. Both hinges came out rather nicely.
Grip A & Grip BFor the manufacturing of the grips we started out with two metal blocks of dimensions seen in (Figure-1A & Figure-1B). We then drilled the blocks with .312 inch diameter holes by setting them in the milling machine, center-drilling and then drilling all the way trough. The blocks were then set in the lathe, which had been equipped with the appropriate readout to make a 45 degree cut into the center of the respective blocks by sweeping the end-mill bit all the way across it. Each block was then flipped and another 45 degree cut as made to create a perpendicular groove all the way across one side of the block and complete the manufacturing of the grip. The figures b