Week 8: Presentation 2, Prototype Progress

The second wave of presentations was today, and much of the progress can be seen in the group presentation in the main blog post. Materials have in large part been taken from the Spartan Superway fabrication shop, with the few materials having been purchased so far including cast iron casters, steel bolts, and corresponding washers and nuts. The prototype is currently being built atop an old lathe stand as a temporary base, as the size and weight of it are useful for resisting the applied forces from the bender.

Week 7: Materials, Design Maturation

The design for the rapid prototype has been reverted towards the original design in lieu of a Hossfeld bender, in light of material acquisition, available support options, and details from the track improvement team. Further revisions will be made as necessary with concerns towards the final design.

Since last week’s post, additional materials have been gathered from the Spartan Superway shop and sourced from local hardware stores for the build. An old lathe stand will be used as a temporary base, as its size and weight appear to be sufficient for the moment. A more permanent stand for placement in the Spartan Superway shop will require additional research at a later date.

In more specific detail:

                A cast iron wheel from a caster will be used on the arm to push against the material.

                The arm may be one of several pieces, either solid rectangular aluminum or tube steel.

                The die will be cut from plywood, with metal banding added if it proves too malleable.

                Pins and the center pivot will be made from either aluminum or steel bar stock.

                The square block to hold the material will be made from square aluminum stock.

                3/8” or ½” shoulder bolts will be used to bolt the bender to the lathe stand.

                Large diamond plate, aluminum plate, or plywood will be used to bridge the lathe stand

plates.

Images:

1) Caster from Harbor Freight.

2) Old lathe stand, Craigslist.

3) Assorted material picked up from Spartan Superway shop.

4) Additional material from Spartan Superway Shop, aluminum plate & plywood.

5) Material list and dimensions.

6) Various bolts from Lowes.

Week 6: Bender Redesign, Need Numbers

The original bender idea has been thrown out completely. Imbalanced forces and unique pieces increase the liability of something breaking, especially in the future where users may assume the system is more robust than it actually is and treat it as such.

Therefore, the focus will now be on replicating a Hossfeld bender or a design very similar to it. The overall simplicity of the design, and the versatility provided by the pin positions, clamping blocks, and die size should be more than sufficient for the needs of the project. The image of the Hossfeld we will attempt to emulate, and the key components identified are below. Die size, the main determinator of our bender’s output, will depend on the final numbers from the track improvement team. The current 18” or 20” radius necessary invalidates a die 1:1 in size, so curves will have to be bent in individual sections.

Week 5: Redesign Details, Bender Rework?

As of the writing of this post, access to on-campus labs has not yet been granted. Work with the track improvement, bogie design, and other teams continue, and final dimensions of the bender have not yet been determined. Initial information from the track improvement team suggests that the radius used will be similar to the largest radius of the track developed last year, which may ease production as having a larger radius will mean that the material may require less force to manipulate. There’s been no new information yet on the radius required for the section of track that constitutes the station, more specifically about whether the dimensions are different or the same compared to what was used previously.

An initial idea for a bender setup was detailed in last week’s post, but evaluation of that design yet continues. Unbalanced forces may prove troublesome over time, so the current thought is to replace the arm with a proper Y-shaped arm, resulting in a design much more similar to a Hossfeld than the original. The base plate may remain the same, unless the bolts/cylinders affixed to it cannot be kept strictly vertical. In either case, the Hossfeld design appears to be much more simple than the DiAcro design, in large part due to the acceptable tolerances on the arms when compared to the circular shape and chain/gear utilized by the DiAcro design. Expect more definite information next week, as prototyping is scheduled to start in short order.