Teflon/Polypropylene Panels

[Buffalo20]

As is my normal, since January, I'm taking Monday off, I still answer the phone to some computer work, but spend the majority of the time in the shop. One of my customers (cheese plant) called to schedule combustion/emissions testing on the (3) 600 hp boilers (25 million BTUs/ea), for either later this week or next week.

They also informed me that there are more of the teflon panels, available, for the first time in about 3 years. They use 22" x. 30" x 1" solid teflon panels in the cheese press, to form blocks of cheddar cheese, about 700# each. After so much use and cleaning, they are replaced, because of cracks, gouges and scratches, so they get replaced. They usually give me 2-3 of them every time I go there, but now they have about 10-12 of them, that are going to the shop. Looks like I'm buying soda and pizza and wings, for the shop.

Over the years, I've made many items out of the panels, cutting boards, slide plates, bump stops, carburetor insulators, soft vise jaws, etc, etc. According to the plant, they are made out of a 60/40 mix of teflon and polypropylene.

I have 5 of the 1" panels (4 full size and 1 cut up into (8) 7" x 11" pieces) and one piece thats 21" x 28" x 3/4" (with holes), in the shop.

I have a project coming up where I'm going to need a couple of 9" plastic gears, wondering how this would hold up.

 

[Bob Korves]

A single test is worth 1000 hobby machinist opinions...

Dupont recommends nylon and Zytel (no surprise, they make it!)
http://www.dupont.com/content/dam/d...l Design Principles/Gear_Brochure_10_2007.pdf

Your material will certainly be low friction. Beyond that, no clue...

 

[Buffalo20]

Bob,

Thanks, that what I thought, looks like everyone is getting a cutting board for Christmas.......

 

[RJSakowski]

Teflon isn't noted for strength. I am not familiar with a Teflon/polypropylene alloy and have not found any reference to it. ^You might ask your customer for their source for the material or a physical properties spec sheet. Polypropylene would likely add rigidity to the material.

If I were selecting a material for plastic gears, Delrin would probably be the first choice. However, you have and ample supply of your plastic and your only loss would be the time spent on making the gears.

Rather than cutting a gear, you might want to machines some test pieces from your plastic and compare to Delrin and/or nylon. I would suggest maybe 1/8" x 1" strip mounted in a vise and measuring deflection and/or shear forces.

 

[Buffalo20]

gear issue was settled at about noon, I called the manufacturer to order the replacement gear, when I was told, they offer an aluminum gear for $11 more than the plastic gear. So the choice was easy.