From: "Rick Maddy" Subject: COZY: Flox Date: Tue, 1 Feb 2000 22:39:00 -0700 I just floxed the longeron doublers in place at the start of chapter 5. During the process I came up with a question. Why are these floxed on instead of just using plain epoxy? What is the proper technique for floxing wood to wood? I just brushed some flox on one piece and pressed the two pieces together so flox oozed out. Is this right? I hope so because the doublers are drying in place as I type this. Rick Maddy (rick@maddyhome.com) Cozy Mk IV #0824: Chapter 5 (www.maddyhome.com/cozy) Date: Wed, 02 Feb 2000 07:08:51 -0500 From: Jeff Russell Subject: Re: COZY: Flox wood parts Rick Maddy wrote: > > I just floxed the longeron doublers in place at the start of chapter 5. > During the process I came up with a question. Why are these floxed on > instead of just using plain epoxy? What is the proper technique for floxing > wood to wood? I just brushed some flox on one piece and pressed the two > pieces together so flox oozed out. Is this right? I hope so because the > doublers are drying in place as I type this. Rick, We bond all of our longerons using only epoxy like glue. In all the years we have done this I have never seen one come apart. We paint epoxy on both sides and clamp together until cured. We flox them to the outer skin and foam shelf of the molded tub then glass the inner skins. hope that helps -- Jeff Russell/AeroCad Inc. Website: http://www.Aerocad.com From: "ZEITLIN,MARC (A-Andover,ex1)" Subject: COZY: Flox wood parts Date: Wed, 2 Feb 2000 07:47:57 -0500 Jeff Russell wrote: Rick Maddy wrote: > > During the process I came up with a question. Why are these floxed on > > instead of just using plain epoxy?...... I hope so because the > > doublers are drying in place as I type this. > We bond all of our longerons using only epoxy like glue. While I'm sure that using pure epoxy will work fine in certain cases (like when the longerons are very flat and clamped) I'll speculate on the rationale for using flox (which Rick is using according to plan here). If the wood isn't perfectly flat, or if it isn't clamped very well, or if it's very warm and the epoxy is thin, you could easily end up with voids in between the wood layers. The flox will deal with these situations by filling the voids and flowing less easily. My $0.02 educated guess. -- Marc J. Zeitlin marc_zeitlin@alum.mit.edu http://cozy.canard.com Non Impediti Ratione Cogitantonis (C&C) Date: Wed, 02 Feb 2000 19:25:35 -0500 From: "L. Wayne Hicks" Subject: Re: COZY: Flox wood parts Jeff Russell wrote: > Rick, > We bond all of our longerons using only epoxy like glue. ------> I'll add my two cents here. In my opinion, you use flow whenever the two mating surfaces aren't exact to each other (or when you want to create a bearing surface...). In the past, I bet the quality of wood wasn't the greatest either, so flox is used to fill any gaps. Jeff's method will work too if the wood surfaces are matched. Maybe the experts can speak up. If Rick wants to use flox, I'd recommend he paint both wood surfaces with a thin layer of epoxy like stated in chapter 3 education section. And Rick, don't worry either way. There's enough glass added in that area later in subsequent chapters. Wayne Hicks http://www.geocities.com/yosemite/falls/2027 From: "Russ Fisher" Subject: Re: COZY: Flox wood parts Date: Wed, 2 Feb 2000 22:29:28 -0500 -----Original Message----- From: ZEITLIN,MARC (A-Andover,ex1) >If the wood isn't perfectly flat, or if it isn't clamped very well, or if >it's very warm and the epoxy is thin, you could easily end up with voids in >between the wood layers. The flox will deal with these situations by >filling the voids and flowing less easily. Here's another reason: with everyone being their own manufacturer, each with varying levels of experience, there is no way to enforce any type of control into the building of an airplane. Some people may become a little "clamp-happy" and apply WAY too much clamping pressure on two parts being joined (I see it all the time with woodworkers). This has the effect of squeezing all the adhesive out of a joint leaving nothing to actually adhere the parts together. The flox acts as a filler to hold some of the epoxy in place and prevent the joint from becoming starved for adhesive. My $.02 worth. Russ Fisher Date: Thu, 03 Feb 2000 05:12:02 -0500 From: Jeff Russell Subject: Re: COZY: Flox wood parts "L. Wayne Hicks" wrote: > > Jeff Russell wrote: > > Rick, > > We bond all of our longerons using only epoxy like glue. > > ------> I'll add my two cents here. In my opinion, you use flow > whenever the two mating surfaces aren't exact to each other (or when you > want to create a bearing surface...). In the past, I bet the quality of > wood wasn't the greatest either, so flox is used to fill any gaps. > Jeff's method will work too if the wood surfaces are matched. Maybe the > experts can speak up. This is true, if the surface does not match up correctly, flox will work better to fill and retain the parts together. We pressure clamp the longerons that have NO voids at all. -- Jeff Russell/AeroCad Inc. Website: http://www.Aerocad.com 2954 Curtis King Blvd. Ft. Pierce, FL. 34946 Shop# 561-460-8020 7:00am to 3:30pm Sponsor- Canard Aviators www.canard.com canard Aviators page From: "Nat Puffer" Subject: COZY: flox Date: Thu, 3 Feb 2000 09:11:58 -0600 Builders, Flox consists of chopped cotton fibers. These impart additional strength to the epoxy. That is why flox is recommended for all structural joints. If two wood surfaces are in intimate contact, flox may not be necessary, but it would be safer to use it, just in case. Doesn't pay to cut corners when building an airplane, at least I wouldn't want to do it if I am going to fly the airplane. Nat