Prototyping: Part 4 – Design & Fabrication

2011 May 31

This week lots of progress was made on the Roaster Project prototype at Acme Metal Works, our prime contractor. With the arrival of all of the purchased components, fabrication of the base table and bowl modifications began. The founder of the company, Tom Eckholdt, did much of the work personally.

Tom began working on the bowl by first clamping on the tabs that will be used in the future. The straight sided portion of the bowl will be separated from the rest of the bowl using a plasma cutter. This upper part will be stationary and will hold the return vanes. It will be held in place by being secured to the table with rods bolted to the tabs. Tom then welded the tabs in place.

He then sent it to the machining station to have a 1 1/4″ hole bored into the center and then threaded. The bowl will be threaded onto the drive shaft and a locking nut used to secure it.

Tom then began taking his measurements for the table to locate the various components he would weld into the table. These include the shaft bearing mounts and the motor mount.
The bearing mounts (two of them) are being machined on a vertical mill by Esperidian Duran.
After installing the bearing mounts and then securing the bearings, the drive shaft with its gear is set in place. Next, the chain is stretched to find the ideal location for the motor mount.
The motor mount is then welded into place. Note that the motor mount has slotted holes to allow us to apply the right amount of tension to the chain.
Under the drive gear will be a thrust bearing and thrust washers to help handle the weight of the bowl and to reduce the axial loading on the shaft bearings.
At the end of last week, this is the state of the Roaster Project prototype. The base table is completed and has all mounts and bearings installed. The bowl is partially machined, awaiting final trim.

Final Assembly of the Prototype

This week, we expect to install the bowl, plasma cut the upper stationary ring off of it, and secure the ring to the table. Then, we will attach the motor, chain, and diverter cone. By then, the water jetted return vane strips should arrive for final assembly.


Comments are closed.