Pages

Monday, September 4, 2017

Weird Materials Question That You Guys and Gals Almost Certainly Can Answer

The bearings on Big Bertha are teflon and FRP.  Is there any reason to be concerned about Breakfree CLP damaging either material?  Cooking spray seems to be short-lived as a lubricant.

5 comments:

  1. Breakfree contains Teflon. I'm not familiar with FRP, and I suspect there is a range of different versions of that plastic product. Might have to track down the manufacturer to be safe. I suspect that it won't damage it, but it's not my bearing, so...

    ReplyDelete
  2. This is a geeky chemist question, really: what's the resistance of a particular type of FRP to solvents? It's my understanding that "plastic" part of FRP can be one of several different polyesters, epoxies, etc. Too much for a simple carpenter at 0600 (and only half-way through my first cup).

    However, the part that I can speak to is the use of cooking spray as a lube. I'd stop that ASAP, clean up the mess, and find something other than that. The reason being that the oils used in cooking spray are "semi-drying" oils that will ultimately partially polymerize and make a damned mess. (Cf. linseed or tung oils that are "drying" oils and will fully polymerize and harden, or, coconut oil which is a "non-drying" oil that won't polymerize at all (or very little) and won't harden.)

    Why not use a Teflon (PTFE) dry lube? A lot less messy, I'd think.

    ReplyDelete
  3. Probably depends on the nature of the FRP. Depends on the type of glass fiber used, probably also depends on the exact nature of the polymer. Epoxies - for example - can exhibit widely differing compression and tensile properties depending on the formulation, cure times, whether they cure at room temperature or need to be heated...

    http://www.owenscorningindia.com/ocindia/Composites/PDF/OC_Chemical_Resistance_Guide_Edition.pdf

    ReplyDelete
  4. Seems like a question properly directed to the manufacturer

    ReplyDelete