High / Low Beam Switch

[CRXSi90]

Got a pix of the bottom of the reservoir? Is it constant cross section? I think I'd rather machine it if it's not too complicated.

[CRXSi90]

Never mind, I found an eBay link that has some good pictures. The one on my bike is flaking away also, which is why I was already sort of thinking of this. In fact, I bounced some ideas off cywelchjr (RIP) back a year and a half ago discussing the material. We never came to any conclusion on it.

http://www.ebay.com/itm/Yamaha-XS110...-/150932877855

There's a good picture of the inside. Looks like fairly good design for a molded part - constant wall thickness. I'm not sure how necessary that "rib" around the top is - that would be difficult to machine. And I'm not sure what the bottom looks like - I've never had mine apart that far. It's an interesting mold with the "Lower" fluid level arrow. I would guess it's not a simple 2- or 3-plate mold and would need to split from the sides also.

[CRXSi90]

..........
I would think that you would then be able to press your model flush into the frame before it sets up (around a minute) to fill all the voids. You would have to do only minimal cutting and would need to take your time to remove the model or part once set.

Then, experiment with resins, etc. and sand out any imperfections on the open side of the finished part.
Advantages:
No special equipment, other than frames.
Quick.
Cheap.
Could make multiple molds to cast several at one time.

All the little nuances could be figured out as they are encountered.
What am I missing here?

My worry with a silicone mold is that it would not give a part that's close enough to the original since it's kinda floppy. The two things I'm concerned about are the core pins where the springs/balls go, and the rectangular posts which core out for the copper tabs. I'm worried that wouldn't work out.

[CRXSi90]

Well, thought I'd post an update on this. Never undertook trying to mold the parts, but I did machine one.

Cut some pockets on one side:


flipped it over, faced it, and cut some more pockets...


cut the outline .007" shy of breaking through. It actually broke loose as I was finishing the outline, so I had to do some cleanup with a file.


contacts fit!


And from the back side...you can see a mistake I made on the curved surface. Mixed up my x and y coordinates. Lucky is wasn't worse.


it fits, but it took some more work with a file. Either I had the tab/hole position too short, or too much material remaining on the switch body. I filed some material off the switch body, but now it slides pretty smooth.


Material is acrylic I believe (grabbed from the scrap bin). Probably not the best choice of materials, so we'll see how long it holds up. If I end up making another, I learned a few things about the sizing and will probably use a different material. This was a fairly time consuming project...probably 10-20 hours. A good challenge non the less. If I get bored some time along, maybe I'll revisit molding these pieces once again.