Friday, January 16, 2015

A "Call Bell", mesaured and recreated in Solidworks

Joseph Piekut: This is the first real object I measured and rebuilt in Solidworks

Q: You said this is your first real object that you measured and created into SolidWorks... So, what is this object? It looks like a bell.

Side view of the final assembly.

Joseph: Yes, it is a bell, a "Call Bell" to be specific.
Q: Why did you chose a bell for your first project?

Photo of the actual bell used for this project.
Joseph: I chose this bell because it looked like a difficult project that would pose some challenges along the way, and I was limited to a project of five parts or less.

Q: Really? What could be challenging or difficult about creating a bell?

Isometric view of the clapper.
Joseph: For one, some parts didn't have specific measurements or shapes, for example, the "clapper" (the part that actually rings the bell) wasn't a perfect rectangle, it had odd cuts in the center so I had to improvise to get it as close as possible.

Q: How do you measure the parts?

Picture of the caliper I used for this project.
Joseph: Good question, I measured all of the parts for this project using a tool called a caliper. It provides measurements that are more accurate than a ruler, specifically measurements up to a thousandth of an inch (or the third decimal place in a number). Just imagine a human hair is .002 of an inch.
Q: Cool, what else was a challenge?

The bolt that the button/pin rests in to hold it in place between the bracket and the shell.
Joseph: Another piece that gave me a bit of a challenge at first was, the bolt that holds the button/pin piece in place. It has multiple shapes directly on top of one another. Some of the shapes couldn't be simply extruded, they had to be carefully sketched and then edited even after extruding or lofting them.

Q: Slow down, what do you mean "extruding or lofting"?

Here is an example of an extrution from a hexagon.

Joseph: An extrusion is when you take a flat 2D sketch and make it 3D by giving a thrid dimension, height.

Q: Oh, ok... Were there any moments when you got stuck and later it hit you how easy it really was?
Isometric view of the bracket piece.

Joseph: Yes actually, this piece shown above, the bracket gave me a lot of trouble at first, I stopped working on the piece and came back to it later when I realized how easy it was. Specifically the hooks on the front in the picture above. It was hard, I tried everything, or so I thought. I tried making new planes, sketching them out, drawing them from every angle. So you can imagine how frustrating it was. In the end all I had to do was create a plane in the center of the curved area and extrude a circle to both faces, this kept the extrude consistent with the curve of the piece. The next step was to cut a smaller circle out of the extruded circle and then just cut a slot so the clapper can slide into the hooks like on the physical bell.

Q: Wow...That is a lot of work. Can you show us what you mean?

Joseph: Here you can see on one side I have the extruded circle and on the opposite side I took the next step and cut out the smaller circle.

Q: You said there were slots that yout cut, where are they? How is the clapper supposed to get in there?

Side view of the bracket to better show off the hooks that hold the clapper.

Joseph: Above you can see the next step in the process of making these hooks, I had to cut out the slot so the prongs on the clapper could slide in.

Q: How does this fit wih the rest of the parts?

Shot to better show how the clapper fits into the bracket hooks.

Joseph: Above you can see how the clapper rests in the hooks, but still has freedom to swing forwards and ring the bell.

Q: Can you show us an exploded view of all the parts together?

Exploded view of the final assembly.

Joseph: Above you can see what the final assembly looks like as individual pieces and how they are assembled.

Q: Wow, that's a lot of work, did you put in this much effort on every part? What other parts did you make and how did you make them?
How It's Made

Isometric view of the metal shell that goes over the bracket.

Metal Bell

The metal bell was one of the easier parts I had to make for this project. It just required me to sketch half of the outline and then revolve that sketch around a center line.

Frontal view of the base part of the bell that the bracket attaches to.

Bell Base: Bottom (Without Bracket)

The bottom part of the base was easy enough. Same as the metal bell. A simple sketch with a revolved base and a few extruded cuts. The only part that took a bit of messing with, was the large center cut.  The ellipse shape didn’t look right. It couldn’t be a perfect circle. It just took some fiddling with. I added a spline and then I mirroried that spline a few more times.

Different view of the bracket piece.

Base Bracket

Simple sketch off of the front plane.   I wanted the top square to resemble that of the bracket on the physical piece. So I added extrudes like the one on the top. To make the hooks, I did a base extrude. After extruding, I had a large circle protruding from the bracket. I cut out the center circle, to leave only a ring. Finally, I cut the missing section from the hooks, so the clapper could slide into the hooks as if it were the physical model.

Isometric view of the base/bracket when assembled.

Side view of the base, bracket.

Bell Base: Complete

Here are a few pictures of the base. This was made from the base and bracket pieces.

Isometric view of the button or pin that you press to ring the bell.

Push Pin: Pin or Hammer Piece

This is the part that  pushes down onto the clapper to make the bell ring. It was a simple extruded circle, with a dome placed on the top. On the flat bottom side of that circle, I extruded another smaller circle to make the shaft of the pin. On the bottom of that pin, I sketched out the hammer looking part and extruded it. Unfortunately, I couldn’t get it to line up perfectly with the bottom of the shaft. It was hardly noticeable regardless, so I left it.

Bolt that holds the push pin.
Push Pin: Bolt

This is the bolt that holds the pin in place between the outside of the metal bell and the bracket.
Mainly just some extrudes combined with a lofted base for the sloped section right beneath the top sphere section. The top sphere was just a sketch with a revolved base. The bottom threads were just an extrude on a helix spiral.

Button/pin and bolt when assembled.
Push Pin: Complete

A view of the final assembly for the push pin and the bolt.

Side/frontal view of the clapper.

This piece was a bit of a challenge at first, I sketched out a triangle for the pyramid shape. Then I cut out a section to separate the top like on the actual model. Next I smoothed out the correct edges using the fillet feature. Then from there I sketched out the body, off of that pyramid and extruded a rectangle. The unique shape comes from the cuts I made on it. This was done to mirror the physical model. The top face was fairly simple. I sketched some splines to curve it and then used the fillet to round out the top to my liking. To make the prongs I sketched directly on the side of the top face, and then used the fillet tool once again to round out the edges.

Thanks for reading my blog.
Joseph Piekut