Injection molded parts designed for ultrasonic welding. We needed to assemble some beta test units for evaluation before the tooling was completed for the Branson ultra sonic welder.

Injection molded parts designed for ultrasonic welding. We needed to assemble some beta test units for evaluation before the tooling was completed for the Branson ultra sonic welder.

Injection molded parts designed for ultrasonic welding. We needed to assemble some beta test units for evaluation before the tooling was completed for the Branson ultra sonic welder.

2 units were modified by hand with an xacto knife. This was too time consuming and not feasible for making 150 units.

From this slide you can see that there are virtually no flat surfaces to hold the part for modification

Here you can see the surface with the energy directors removed.

This is a photo of the actual part with the energy directors visible

Model of the housing with energy directors

From this view you can see the elevation changes the tool must follow to cut off the energy directors.

Another photo of the actual part

Its curved along this part of the path as well

This is the solid model of the fixture design from solidworks.

Solid model with the part model inserted in the fixture.

We used out Stratasys FDM machine to build the fixture in PCABS blend material. The fixture was built using the sparse feature of the insight software so the inside of the part is corrugated. I made the “skin” of the fixture 0.080” thick. Build time was less than 5 hours built sparse vs. a full solid build which would have taken just over 10 hours.

The part is clamped from the sides when the fixture is squeezed by the vise. This changes the position of the part slightly which must be corrected but it holds the part sequrely and is easy to load and unload without any clamps to avoid.

The part has a rubber like coating on the outside and this also helps keep it secure in the fixture when squeezed.

Here you can see the assembled housing. Note that the part doesn’t fit together correctly because of the energy directors

IMG_2661

Here you can see both a flat 2d geometry layer at Z0 as well as the 3d tool path layer. The actual path geometry was offset from the model in mastercam by my friend Terence which was then imported into GP to post.

A picture of the cut part

A picture of the un-cut part

We were able to recycle the fixture to hold the top cover to increase the clearance around the 1-9 keys

Rubber bands were the easiest way to hold the housing in the fixture for machining…..Don’t laugh, it worked and I didn’t have to add any clamps to the fixture (remember that it is essentially hollow inside because it was built sparse by the FDM machine)