---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Fri 11/07/03: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:08 AM - Re: Cortec 373 versus 374 primer (Robert Eli) 2. 06:24 AM - Re: CH 701 fuselage (Ron DeWees) 3. 07:41 AM - Re: engraving id on some parts (Carlos Sa) 4. 08:04 AM - Re: Cortec 373 versus 374 primer (lnk@cis.net) 5. 08:49 AM - Re: CH 701 fuselage (Bill Howerton) 6. 10:12 AM - Re: CH 701 fuselage (Johann) 7. 12:46 PM - Re: engraving id on some parts (Jack Russell) ________________________________ Message 1 _____________________________________ Time: 05:08:31 AM PST US From: "Robert Eli" Subject: RE: Zenith-List: Cortec 373 versus 374 primer --> Zenith-List message posted by: "Robert Eli" Eric, I made a lot of phone calls and Emails, and it was surprisingly difficult to get anyone to just tell me in practical terms what the surface preparation should be. I finally did get complete information and will submit a full report over the week end. Basically, the Cortec 373 can be brushed, sprayed, or dipped, requiring only a few mils thickness to give complete protection. New aluminum surfaces need only to be degreased (no roughing the surface needed) using any suitable solvent degreaser. The Cortec people use methanol (alcohol), since it is more user friendly than something like lacquer thinner. I'm convinced that this primer is far superior to any other alternative for my use in the tight confines of my basement. Bob Eli Email: robert.eli@adelphia.net -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Eric Tauch Subject: Re: Zenith-List: Cortec 373 versus 374 primer --> Zenith-List message posted by: "Eric Tauch" Hi Bob, Any more info on the Cortec. I think I will just go ahead and order a quart. Thanks, Eric ----- Original Message ----- From: "Robert Eli" Subject: Zenith-List: Cortec 373 versus 374 primer > --> Zenith-List message posted by: "Robert Eli" > > I am beginning my CH701 construction and have been concerned about > understanding priming pros and cons with respect to the Cortec products. I > have been doing research on subject, and have talked to the Cortec people > and to Nick at ZAC about which product is best for aircraft interior > surfaces (he said that Cortec recommended the 373 instead of alternate > products). This is an interim report on what I have learned. First, the > most appropriate product is the Cortec 373 wash primer that is supplied by > ZAC in quarts (according to the Cortec chemist and engineer). Boeing > Aircraft Co. has used this product on some of their production aircraft > interior surfaces, to name one usage example. The Cortec chemist does not > recommend the 374 primer for our purposes. I am gathering specs and surface > preparation details, and will report more extensively on this subject as > soon as I receive the information from Cortec. > > > Bob Eli > > CH701 > > ________________________________ Message 2 _____________________________________ Time: 06:24:11 AM PST US From: "Ron DeWees" Subject: Re: Zenith-List: CH 701 fuselage --> Zenith-List message posted by: "Ron DeWees" Hi Tony and others, I took special interest in this thread about sound blocking since I used one in my 601 HDS. I asked questions and posted information on the list and got absolutely no interest so I just forgot about it till the subject came up again. I found a product called Noise Killer NK-118 on the internet for about $55 a gallon and applied it with a brush to my 601 and LOVE it. It's a bit like very thick latex paint in a light grey color. You can apply one to three coats with a brush, roller, or sprayer. The jug of it is heavy. I estimate it as about 10 pounds, but it's water soluble and the water alone would account for the first 8 pounds of weght. The tech data says that the active ingredient is CAS 74%. It claims a noise reduction of from 3db to 20db. It says it will not burn and calls itself a noise and vibration absorber as opposed to being only a barrier. THere is an 800 number on the website and I talked at length with a technical person there. He says it's used by racecar drivers and is fine for airplanes. He said he thought it was approved for certified planes but didn't send any info with the product. I painted the inside of the fusalage from the baggage compartment to the firewall and it's effect is dramatic. If you tap on the large panels of unsupported aluminum you now hear a "thunk" sort of sound rather than a loud rattle. Since it has a bit of texture if you brush it on, it will act as a sort of interior coating to stand alone or be painted. It's also sort of a non-skid surface and will work well in the bagage compartment to resist items sliding around as much. You can scrape it off it you want to remove a pop rivit from a painted area. I expect a significant reduction in cabin noise since on the 601 you have your head in front of the lugage compartment and it's almost like a big bell with a lot of unsupported metal. I used only about 3 quarts of it in painting and don't think I will put any of it in the rear fusalage. I expect it will also act as a temperature insulator if you paint cabin skins with it rather than upholster them. Hope this is helpful to others as I am pleased so far with this product. Ron DeWees 601 HDS/Jab 3300 80% done ----- Original Message ----- From: "Tony & Peggy Pierce" Subject: Re: Zenith-List: CH 701 fuselage > --> Zenith-List message posted by: "Tony & Peggy Pierce" > > Thanks for all the response to my 'oil canning' question...we now have > several things to consider. It's really great to have this resource for > obtaining timely information as we build this airplane. > Thanks, > Tony > > ________________________________ Message 3 _____________________________________ Time: 07:41:41 AM PST US From: Carlos Sa Subject: Re: Zenith-List: engraving id on some parts --> Zenith-List message posted by: Carlos Sa Eric, I asked a similar question not long ago. The easiest thing is to mark the part whith a Sharpie pen (in two or three places, because if you overspray with primer, the ink may run and the identification may become hard to read). I did use tags as a back up last time I primed a large batch of parts, but next time I will tag only parts that are similar (just in case). The Sharpie marks work well. I wouldn't engrave anything, I'm just too paranoid. Cheers Carlos > I was wondering if it wouldnt be too "damaging" to engrave a very small A,B,C,D, etc in the > corner tip of some of > these pieces. ________________________________ Message 4 _____________________________________ Time: 08:04:40 AM PST US From: "lnk@cis.net" Subject: RE: Zenith-List: Cortec 373 versus 374 primer PRIORITY_NO_NAME --> Zenith-List message posted by: "lnk@cis.net" It's interesting that this came up in the middle of the flurry of e-mails regarding sond deadening. My question now is, how well do the various sound deadening methods adhere to the various corrosion inhibiters? Larry Kilburg Original Message: ----------------- From: Robert Eli robert.eli@adelphia.net Subject: RE: Zenith-List: Cortec 373 versus 374 primer --> Zenith-List message posted by: "Robert Eli" Eric, I made a lot of phone calls and Emails, and it was surprisingly difficult to get anyone to just tell me in practical terms what the surface preparation should be. I finally did get complete information and will submit a full report over the week end. Basically, the Cortec 373 can be brushed, sprayed, or dipped, requiring only a few mils thickness to give complete protection. New aluminum surfaces need only to be degreased (no roughing the surface needed) using any suitable solvent degreaser. The Cortec people use methanol (alcohol), since it is more user friendly than something like lacquer thinner. I'm convinced that this primer is far superior to any other alternative for my use in the tight confines of my basement. Bob Eli Email: robert.eli@adelphia.net ________________________________ Message 5 _____________________________________ Time: 08:49:37 AM PST US From: "Bill Howerton" Subject: Re: Zenith-List: CH 701 fuselage --> Zenith-List message posted by: "Bill Howerton" I can't imagine that the L-angles and the sound-deadener could really add that much weigh or have too much of an affect on the CG. In fact the occasional trip to the gym for the deadweight in the left seat should more than counteract it. That having been said, it would seem we may be talking about two distinct issues -- one is oil-canning - which I would thing that diagonal supports would tend to alleviate, and vibration which I would imaging the rolled sound deadener (or quiet-cote) would alleviate. Are these valid assumptions? Is it unnecessary (or even a bad idea) to use both methods? Also what is this "Z-Wave" that Larry mentioned? Bill Howerton -N714BH (yes, I now have my N-Number) 601XL - Corvair tail done, fuselage 75% > > Tony, > > I've seen several 601s and 701s that used a heavy duct tape in an X between > > frames to minimize the oil-canning > > and was told that it worked rather well. The diagonal framing on the other > > hand will leave you with a Z-wave that > > is very predominant in the summer sun if that matters, but doubt that will > > solve the oil canning as well as a contact > > adhesive, tape, spray or padding. > > > > Larry McFarland - 601hds @ www.macsmachine.com > > > ________________________________ Message 6 _____________________________________ Time: 10:12:34 AM PST US From: "Johann" Subject: RE: Zenith-List: CH 701 fuselage --> Zenith-List message posted by: "Johann" Hello list members. I am sorry to say that my plane is still standing in the garage and needs an engine to try out the "L" stiffeners. I am at a point in the building, where a lot of money is needed to complete. Hope something will happen next summer. (Lottery or something like that) Happy building, Johann G. Iceland. Hey Tony, Check out Johann's site (click on Zenith on the side bar, then fuselage at the top) http://www.gi.is/fis/ he has also added some strigers to prevent oil canning. I am thinking that I am going to do the same. I see Larry was talking about some users using tape with good results. I can't say which is best. Maybe Johann will chime in and give his results. Good Luck, Keith CH701 a long ways to go (only 170% more) ________________________________ Message 7 _____________________________________ Time: 12:46:43 PM PST US From: Jack Russell Subject: Re: Zenith-List: engraving id on some parts --> Zenith-List message posted by: Jack Russell Carlos Sa wrote: --> Zenith-List message posted by: Carlos Sa The easiest thing is to mark the part whith a Sharpie pen (in two or three places, because if you overspray with primer, the ink may run and the identification may become hard to read). By the way, I found that the fat sharpies will run with the primer and the fine point sharpies don't. Go figure. Jack Russell