---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Wed 02/08/06: 12 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:41 AM - Re: Re: green scotchbrite (Bryan Martin) 2. 03:24 AM - Re: green scotchbrite (Mike Hoffman) 3. 05:49 AM - Re: Re: green scotchbrite (Aaron) 4. 07:03 AM - Re: Propeller Balancing (Hinde, Frank George (Corvallis)) 5. 07:11 AM - EVIL SCOTCHBRITE (Garrou, Douglas) 6. 07:49 AM - Re: Propeller Balancing (R.P.) 7. 10:51 AM - Re: EVIL SCOTCHBRITE (Weston, Jim) 8. 10:51 AM - Re: Re: Corrosion Prevention: Alodine and Zinc Chromate: folow ups, pics and scotchbrite (japhillipsga@aol.com) 9. 10:57 AM - Re: Propeller Balancing (japhillipsga@aol.com) 10. 01:29 PM - Re: EVIL SCOTCHBRITE (B Johnson) 11. 03:35 PM - Re: green scotchbrite (Ron Lendon) 12. 04:08 PM - Re: EVIL SCOTCHBRITE (n801bh@netzero.com) ________________________________ Message 1 _____________________________________ Time: 02:41:35 AM PST US Subject: Re: Zenith-List: Re: green scotchbrite From: Bryan Martin --> Zenith-List message posted by: Bryan Martin If you are talking about the green scrubbing pads from the grocery store, I haven't found any good information about that. Someone mentioned part number 7447. I found some information at the 3M website about that. I don't know if they are the same product. The 3M website has a link to search for MSDS sheets by UPC code, you might try that if you still have any of the packaging from the product you bought. -- Bryan Martin N61BM, CH 601 XL, Stratus Subaru. do not archive. on 2/7/06 10:11 PM, Dave VanLanen at davevanlanen@sbcglobal.net wrote: > --> Zenith-List message posted by: "Dave VanLanen" > > > Bryan, > > So are you saying that the "green stuff" is OK? I purchased the green > stuff, but could not find a part number on the product, so I don't know if I > got part 7447+ or not. Since I haven't started building yet, I guess I'd > like to know for sure if it is OK to use. I haven't seen any red stuff - > wouldn't even know where to get that. > > Thanks, > Dave > > Do not archive > > Time: 06:10:02 PM PST US > Subject: Re: Zenith-List: Re: green scotchbrite > From: Bryan Martin > > --> Zenith-List message posted by: Bryan Martin > > The 3M MSDS sheet for product P/N 7447+ shows that it uses an aluminum oxide > abrasive so it should be correct for use on aluminum. I guess you can't tell > what abrasive is used in the product by its color. > ________________________________ Message 2 _____________________________________ Time: 03:24:28 AM PST US From: "Mike Hoffman" Subject: Zenith-List: Re: green scotchbrite --> Zenith-List message posted by: "Mike Hoffman" Steve, I have stripped and repainted 4 aircraft and numerous cars and boats. I have used the "green scotch pads" with no problems what so ever. I have also, on occasion, used marine Zink chromate when the aviation specific Zink was not readily available. I also am using green scotch pads to scuff the surfaces on my 701. Do not archive. Just my 2 cents. Mike Hoffman ________________________________ Message 3 _____________________________________ Time: 05:49:53 AM PST US From: "Aaron" Subject: Re: Zenith-List: Re: green scotchbrite --> Zenith-List message posted by: "Aaron" My Ace Hardware has all the colors. Just different coarseness. The gray is fine and the red and green more coarse. I forget witch one is most coarse. I have also seen some really coarse stuff used for scrubbing floors. It may not be true to the color scheme. Aaron do not archive ________________________________ Message 4 _____________________________________ Time: 07:03:43 AM PST US Subject: RE: Zenith-List: Propeller Balancing From: "Hinde, Frank George (Corvallis)" --> Zenith-List message posted by: "Hinde, Frank George (Corvallis)" Indeed, But that is resonance which is not the same as assuming that it is a good thing to have the prop blade going the other way to the nearest piston. Its (as you say) a much more complex system than that. In fact, that is why the reduction drive manufacturers use an "odd ratio" 2.1:1 in the case of the Stratus...This means the prop is constantly moving relative to the engine to avoid getting a standing resoanant wave. There is a resonant point somewhere along the travel though, that is why we get the classic "rum rum" sound and feel from the engine. I agree props are complex animals, wish I had time to study the physics more..:), Maybe after I finish the RV. Frank Do not archive -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of doug kandle Sent: Tuesday, February 07, 2006 3:40 PM Subject: RE: Zenith-List: Propeller Balancing --> Zenith-List message posted by: doug kandle I too have had very good results from dynamic balancing. Even after a new 72", balanced at the factory, three blade prop had been installed on an IO-520, the dynamic balancing still made quite a difference. As for indexing. A few years ago I had a long talk with one of the engineers at Macauley. I wanted to know why a particular prop could be used on another aircraft but not on mine even though the two used the same engine. What I came away with from that discussion was a much better appreciation of how much complex engineering goes into propeller design. The entire engine, prop, and engine mounting structure must be considered. It is a dynamic system and resonances are an important component. The prop flexes, the engine mounts move, and the forces on the system are impulsive. This all leads to a very complicated system. This is one area that it is best not to do much experimenting and just go with the propeller manufacturers recommendations. I have been told that on some prop-engine-mounting combinations that the orientation of the propeller relative to the crank shaft is critical to avoid resonance problems. At 03:41 PM 2/7/2006, you wrote: >--> Zenith-List message posted by: "Hinde, Frank George (Corvallis)" > > >Indexing the prop I simply don't buy...If the prop is balanced it is >already balanced relative to istelf. It should make no difference how >it is indexed. > >Dynamically balancing does make make a HUGE difference that I can vouch >for personally. > >Frank > >Do not archive > >-----Original Message----- >From: owner-zenith-list-server@matronics.com >[mailto:owner-zenith-list-server@matronics.com] On Behalf Of kevinbonds >Sent: Tuesday, February 07, 2006 2:17 PM >To: zenith-list@matronics.com >Subject: RE: Zenith-List: Propeller Balancing > >--> Zenith-List message posted by: "kevinbonds" >--> > >Statically or dynamically? A friend of mine dynamically balanced his >prop recently. He paid a guy about $150 to hook it up to a machine; run >it up to cruise speed; and balance it there. Man does it fly smoother >now! I watched the whole process and asked questions. Very cool. I do >not often here anyone talk about dynamically balancing a prop. Seems >like one of those things that people regard as voodoo or snake-oil or >something. Also talk of indexing ones prop to the piston closest to it, >so that the weight of the blades doesn't coincide with the force of the >combustion event (I am not completely clear on this myself, just seen >some valid arguments for doing so) is not often mentioned. I will be >giving these things more thought as I get closer. >Seems like a good idea to index then dyn. Balance. FWIW > >Kevin Bonds > >Nashville TN > >601XL Corvair powered; Plans building. > >Empennage done; working on wings and engine. > >http://home.comcast.net/~kevinbonds > > >do not archive DO NOT ARCHIVE > > >-----Original Message----- >From: owner-zenith-list-server@matronics.com >[mailto:owner-zenith-list-server@matronics.com] On Behalf Of Jeffrey J >Paris >Sent: Tuesday, February 07, 2006 11:56 AM >To: zenith-list@matronics.com >Subject: Zenith-List: Propeller Balancing > >--> Zenith-List message posted by: "Jeffrey J Paris" > > > >Guru's of the Zenith List, > >I've Googled without much luck, but does anyone have an inexpensive >way, directions, instructions to balance ones' wooden propeller? I'm >curious to see what has to be said? > >Thank you for your time and consideration. > >Jeff Paris >N196ZP CH601XL Jabiru 3300 >45 hours in the air and loving every minute of it!!!! > > ________________________________ Message 5 _____________________________________ Time: 07:11:51 AM PST US Subject: Zenith-List: EVIL SCOTCHBRITE From: "Garrou, Douglas" --> Zenith-List message posted by: "Garrou, Douglas" For those who have used green Scotchbrite, fear not: if this product results in the destruction of your airframe, I will represent your bereaved relatives and estate against 3M -- pro bono. Seriously, what could a green Scotchbrite possibly do to aluminum sheet that would damage it?!? True, I'm nobody's idea of an engineer -- you can trust me on that, or you could just ask the Chief Engineer for Project 801, where my official position apparently is "chief self-inflicted injury receiver." But in any event, my pea-brain can't get itself around the idea of a color-coded killer Scotchbrite. I am, however, starting to get nervous. Now, whenever I see the green Scotchbrite on the shelf at Project 801 HQ, that evil bad-guy music from Star Wars starts playing in my head. I also think that aircraft listed for sale in Trade-a-Plane should have to identify total time on the airframe, total time on the engine since overhaul, and whether a green Scotchbrite has ever been within 75 feet of the aircraft. Finally, I have taken to wearing a maroon Scotchbrite on a string around my neck when I sleep, to ward off the evil green spirit. Really, you just can't be too careful. Doug Garrou Project 801 www.garrou.com p.s. You know you can trust me: My hair is sort of maroon-colored. -----Original Message----- > > > > Green dust??? Sounds, like you are using the green Scotchbrite. No good for > > aluminum. Use only the darl red stuff. ________________________________ Message 6 _____________________________________ Time: 07:49:26 AM PST US From: "R.P." Subject: Re: Zenith-List: Propeller Balancing --> Zenith-List message posted by: "R.P." ----- Original Message ----- From: "Jeffrey J Paris" Sent: Tuesday, February 07, 2006 9:55 AM Subject: Zenith-List: Propeller Balancing > --> Zenith-List message posted by: "Jeffrey J Paris" > > > > Guru's of the Zenith List, > > I've Googled without much luck, but does anyone have an inexpensive way, > directions, instructions to balance ones' wooden propeller? I'm curious > to see what has to be said? > > Thank you for your time and consideration. > > Jeff Paris > N196ZP CH601XL Jabiru 3300 > 45 hours in the air and loving every minute of it!!!! Funny you should ask, I just went through a little balancing act on my Sensenich/Jab3300 installation. I'd just changed props on my 601HD, but was getting a lot of vibration from the new prop. I pulled the prop back off of the plane and checked it out on a homemade knife-edge balancer. A piece of 1" diameter tubing was inserted through the ceneter hole in the prop and laid across 2 parallel knife edges made from some scrap .060 aluminum clamped to a couple of 2x4's laid flat and level on the workbench. The 1" diameter tube was laid across the knife edges and gravity took it's course, one blade of the prop would consistantly drop down and lay on the table. I sprayed a couple light coats of flat black spraypaint on the backside of lighter blade and tried the balance act again. After letting the paint dry I found I was close, but still not perfect. Another light spray and another day of drying came up with the right combination: the prop would lie perfectly still on the knife edges with niether blade trying to drop down. After re-installing the prop the vibrations were gone :) Rick Pitcher ________________________________ Message 7 _____________________________________ Time: 10:51:10 AM PST US Subject: RE: Zenith-List: EVIL SCOTCHBRITE From: "Weston, Jim" --> Zenith-List message posted by: "Weston, Jim" Ok, this is getting really fun. So I can't resist to put in my two cents. I don't know about the color coding, but the problem is that some pads are manufactured with Aluminum Oxide as the abrasive, and some are manufactured with Iron Oxide as the abrasive. Iron Oxide is very very very bad to use on aluminum. During the process of scrubbing the aluminum small particles of iron oxide are embedded within the aluminum. The contact between dissimilar metals and the rusting action of the iron causes corrosion to form. WE DON'T WANT CORROSION ON OUR ALUMINUM AIRPLANES. I may have the physics/chemistry of the situation a bit wrong, but the effect is the same. Unless you figure out the color code issue, buy your scotch brite type of pads at the local auto paint shop and make sure that the abrasive is aluminum. Jim Weston Concord, Ga. -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Garrou, Douglas Sent: Wednesday, February 08, 2006 10:11 AM Subject: Zenith-List: EVIL SCOTCHBRITE --> Zenith-List message posted by: "Garrou, Douglas" --> For those who have used green Scotchbrite, fear not: if this product results in the destruction of your airframe, I will represent your bereaved relatives and estate against 3M -- pro bono. Seriously, what could a green Scotchbrite possibly do to aluminum sheet that would damage it?!? True, I'm nobody's idea of an engineer -- you can trust me on that, or you could just ask the Chief Engineer for Project 801, where my official position apparently is "chief self-inflicted injury receiver." But in any event, my pea-brain can't get itself around the idea of a color-coded killer Scotchbrite. I am, however, starting to get nervous. Now, whenever I see the green Scotchbrite on the shelf at Project 801 HQ, that evil bad-guy music from Star Wars starts playing in my head. I also think that aircraft listed for sale in Trade-a-Plane should have to identify total time on the airframe, total time on the engine since overhaul, and whether a green Scotchbrite has ever been within 75 feet of the aircraft. Finally, I have taken to wearing a maroon Scotchbrite on a string around my neck when I sleep, to ward off the evil green spirit. Really, you just can't be too careful. Doug Garrou Project 801 www.garrou.com p.s. You know you can trust me: My hair is sort of maroon-colored. -----Original Message----- > > > > Green dust??? Sounds, like you are using the green Scotchbrite. No > > good for aluminum. Use only the darl red stuff. ________________________________ Message 8 _____________________________________ Time: 10:51:36 AM PST US From: japhillipsga@aol.com Subject: Re: Zenith-List: Re: Corrosion Prevention: Alodine and Zinc Chromate: folow ups, pics and scotchbrite --> Zenith-List message posted by: japhillipsga@aol.com Dan, the brown or maroon pad it courser than the green. The reason there may be some hesitation on our part to say what is right or wrong is that we are not sure exactly what and when you plan to do with the metal. On my XL I used the maroon pads to clean and scuff the metal before re cleaning with lacquer thinner and wax /grease cleaner then priming with epoxy primer. When the epoxy seals corrosion is dead. Best of luck, Bill -----Original Message----- From: Dan Morehouse Sent: Tue, 7 Feb 2006 07:10:10 -0800 (PST) Subject: Zenith-List: Re: Corrosion Prevention: Alodine and Zinc Chromate: folow ups, pics and scotchbrite --> Zenith-List message posted by: Dan Morehouse Thanks everybody for being thankful. I've taken so much from this group over the past several months, so it's nice to add something. I'll be asking a few follow up questions to these guys in a little while, so please post any you have. I'll ask about the stain 'shadow' that remains or recurrs. I was told it's fine to paint over, but I will double check to make sure it would be nothing but a minor cosmetic defect. I hit the aluminum with a Blendes drum and also with Alumiprep and scotchbrite for the first time last night. The Alumiprep didn't work so-so. I used a GREEN scotchbrite and maybe 20# hand pressure after mixing the Alumiprep 1:2, the highest suggested mix ratio. Did that after a 6-8 minute dwell time. The Blendex drum on an angle grinder by itself worked much better. It looked like that stain shadow was left after an initial pass using 10-20# pressure on the grinder. It was much shinier and the shadow was only noticeable at certain reflective angles. I'm not sure this is what Dr. Dean talked about or not. I was able to get rid of it with a second pass and twice as much pressure. If this will be the interior side, I might not even have to do that. One of my questions I'll ask. I emailed a few pics of this to the list. I'm told it may take a few days to post and the group will be notified. Finally, it seems there's a debate on the grade of scotchbrite to be used. I'm using green and have heard others say maroon is better. Is that a finer or coarser grade? Cheers, Dan --------------------------------- ________________________________ Message 9 _____________________________________ Time: 10:57:21 AM PST US From: japhillipsga@aol.com Subject: Re: Zenith-List: Propeller Balancing --> Zenith-List message posted by: japhillipsga@aol.com Jeff, Spruce has (had) an inexpensive plug, line level, string device for sale to balance props. Saw it, but have not used it. Seem similar devices in other DIY plane building books, Bill -----Original Message----- From: Jeffrey J Paris Sent: Tue, 7 Feb 2006 12:55:39 -0500 (EST) Subject: Zenith-List: Propeller Balancing --> Zenith-List message posted by: "Jeffrey J Paris" Guru's of the Zenith List, I've Googled without much luck, but does anyone have an inexpensive way, directions, instructions to balance ones' wooden propeller? I'm curious to see what has to be said? Thank you for your time and consideration. Jeff Paris N196ZP CH601XL Jabiru 3300 45 hours in the air and loving every minute of it!!!! ________________________________ Message 10 ____________________________________ Time: 01:29:36 PM PST US From: "B Johnson" Subject: RE: Zenith-List: EVIL SCOTCHBRITE --> Zenith-List message posted by: "B Johnson" Jim, It appears that what I have (not actually "green" per-say, looks more like army green) is "silicon carbide" any thoughts on that??? More fun??? Bruce Johnson Hoping my Sonex doesnt fall out of the sky because I bought cheep surplus scotch=brite. -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Weston, Jim Sent: Wednesday, February 08, 2006 12:46 PM Subject: RE: Zenith-List: EVIL SCOTCHBRITE --> Zenith-List message posted by: "Weston, Jim" Ok, this is getting really fun. So I can't resist to put in my two cents. I don't know about the color coding, but the problem is that some pads are manufactured with Aluminum Oxide as the abrasive, and some are manufactured with Iron Oxide as the abrasive. Iron Oxide is very very very bad to use on aluminum. During the process of scrubbing the aluminum small particles of iron oxide are embedded within the aluminum. The contact between dissimilar metals and the rusting action of the iron causes corrosion to form. WE DON'T WANT CORROSION ON OUR ALUMINUM AIRPLANES. I may have the physics/chemistry of the situation a bit wrong, but the effect is the same. Unless you figure out the color code issue, buy your scotch brite type of pads at the local auto paint shop and make sure that the abrasive is aluminum. Jim Weston Concord, Ga. -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of Garrou, Douglas Sent: Wednesday, February 08, 2006 10:11 AM Subject: Zenith-List: EVIL SCOTCHBRITE --> Zenith-List message posted by: "Garrou, Douglas" --> For those who have used green Scotchbrite, fear not: if this product results in the destruction of your airframe, I will represent your bereaved relatives and estate against 3M -- pro bono. Seriously, what could a green Scotchbrite possibly do to aluminum sheet that would damage it?!? True, I'm nobody's idea of an engineer -- you can trust me on that, or you could just ask the Chief Engineer for Project 801, where my official position apparently is "chief self-inflicted injury receiver." But in any event, my pea-brain can't get itself around the idea of a color-coded killer Scotchbrite. I am, however, starting to get nervous. Now, whenever I see the green Scotchbrite on the shelf at Project 801 HQ, that evil bad-guy music from Star Wars starts playing in my head. I also think that aircraft listed for sale in Trade-a-Plane should have to identify total time on the airframe, total time on the engine since overhaul, and whether a green Scotchbrite has ever been within 75 feet of the aircraft. Finally, I have taken to wearing a maroon Scotchbrite on a string around my neck when I sleep, to ward off the evil green spirit. Really, you just can't be too careful. Doug Garrou Project 801 www.garrou.com p.s. You know you can trust me: My hair is sort of maroon-colored. -----Original Message----- > > > > Green dust??? Sounds, like you are using the green Scotchbrite. No > > good for aluminum. Use only the darl red stuff. -- -- ________________________________ Message 11 ____________________________________ Time: 03:35:06 PM PST US Subject: Zenith-List: Re: green scotchbrite From: "Ron Lendon" --> Zenith-List message posted by: "Ron Lendon" It looks like the green pads are for scouring. Here is a link to 3m's site: -------- Ron Lendon, Clinton Township, MI Corvair Zodiac XL, ScrapBuilder Read this topic online here: http://forums.matronics.com/viewtopic.php?p=10918#10918 ________________________________ Message 12 ____________________________________ Time: 04:08:56 PM PST US From: "n801bh@netzero.com" Subject: Re: Zenith-List: EVIL SCOTCHBRITE --> Zenith-List message posted by: "n801bh@netzero.com" Finally, I have taken to wearing a maroon Scotchbrite on a string around my neck when I sleep, to ward off the evil green spirit. Really, you just can't be too careful. Doug Garrou Project 801 www.garrou.com p.s. You know you can trust me: My hair is sort of maroon-colored. ////////////////////////////////////////// Ya know, The image of green colored scotchbrite hair flashed through my brain for a second. All I saw was a Don King looking guy at a salad bar... EEEWWWWWW... Of course, DO NOT ARCHIVE. Ben Haas N801BH www.haaspowerair.com Finally, I have taken to wearing a maroon Scotchbrite on a string around my neck when I sleep, to ward off the evil green spirit. Really, you just can't be too careful. Doug Garrou Project 801 www.garrou.com p.s. You know you can trust me: My hair is sort of maroon-colored. ////////////////////////////////////////// Ya know,The image ofgreen colored scotchbrite hair flashed through my brain for a second. All I saw was a Don King looking guy at a salad bar... EEEWWWWWW... G Of course, DO NOT ARCHIVE. BenHaas N801BH www.haaspowerair.com