Attempt Zero: Casting a crude HBLB and machining it to death!


Since I have some crude machinery and casting ability, I decided to use the lost foam casting technique to fashion a rough bearing holder and then finish up with a bit of machining. To make the pattern, I drew the part up in TurboCad2D and then printed out the shape. I then cut these out and pinned them onto a hunk of floral arrangement foam. Unfortunately, the foam was too dense and didn't melt when I poured the aluminum into the mold. So, I had to make the pattern out of wood and then cast it with the more traditional split pattern casting method.

Laying out the foam model


The model begins to take shape


Almost ready to invest the model into the sand


TOTAL FAILURE...THE FOAM DID NOT MELT AND THE PART WAS SCRAPPED! I went ahead and made a wood model and then rammed up a mold to accomodate the part. This worked much better.




The HBLB hot out of the mold


After a bit of finish machining (make that about a zillion hours of finish machining...)


Ready to install the bearings


Bearings installed and ready to slide


This proof of concept is a little rough, but it works great. The next generation will have a better finish and more accurate machining.


This rolls extremely smooth with abec 5 bearings on a nice piece of 3/4" CRS


Well, I consider this part a trial due to the amount of machining required to finish it up. The part was very difficult to clamp due to its shape, and I didn't get the hole drilled exactly in the center. I'll probably keep this part around as something to look at and remember back, but it will never see a CNC machine because it just isn't good enough.