| Metal Polishing Non-Clad Sheet Metal Procedures
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NuShine II Metal Polish
The following polishing procedures are a compilation of many methods developed through our own use of our products in field and lab testing, and from the many customers who have offered their own findings through their experiences in the field.
Although the following is a recommended procedure, it may not be the only procedure to provide good results. Metal polishing is at least as much an art as a procedure, but we have found that the following method will usually give you outstanding results in the shortest amount of time –and with the least amount of hard work. Join in the fun, and give your aircraft, boat, bike, car or RV the personalized touch of a truly "knock your socks off", outstanding polish finish – with the absolute best depth, clarity and image obtainable, anywhere, any way – period! Believe it or not… users of Nuvite NuShine II have coined the phrase “The Nuvite Look” to describe the excellence of polish jobs on aircraft. …Well, we couldn’t say it better ourselves!
“The Better the Polish Job, The Longer It Lasts!”
It’s true! -once the surface is polished to that clear, deep image Nuvite NuShine II offers, (aka. “That Nuvite Look”) and the more times it gets that Nuvite polish job, the longer it will last. This is because the metal surface becomes better and better. The surface is more “healed”. The Nuvite system of Graded polishes allows you to truly remove embedded oxidation. Oxidation left in the polished surface rapidly increases the breeding of more oxidation, causing the polish job to dull quicker. The cleaner the surface of oxidation, the longer the polish job lasts.
“One Grade of Polish Can’t Do It All”
Nuvite’s NuShine II polishes are designed, specifically, to be a "System" of differing polishes – with characteristics that do specific tasks that will save you time and a great deal of effort to accomplish the particular phase of the process leading to the outstanding results you, and we, desire.
The Nuvite NuShine II Metal Polish System
Finishing Grades:
For use after surface of the metal has been “healed” or prepared with the compounding Grades listed below.
NuShine II Grade S – the finishing grade that gives the really deep, clear image when used as a final finish over a properly prepared, oxidation-free surface. (Here’s “The Nuvite Look”)
NuShine II Grade A – a medium-finish grade that gives a clear, clean shine and can be used as a light compounding grade to remove very slight oxidation, such as when a good polish job starts to slightly degrade. Also useful for hand polishing in tight spots where buffers cannot reach. Will give good finishes good, bright look similar to usual commercial grade polishes, but does not offer the “spectacular look” of NuShine II Grade S.
Compounding Grades:
Before a polished metal surface can present a really clear deep image, it needs to be prepared for the final finish to “heal the surface”. One or more of the NuShine II Compounding Grades may need to be used before the final “Nuvite Look” can be achieved.
NuShine II Grade C – C is a light compounding grade polish that we recommend to use
for prep of already polished surfaces prior to using Grade S. Grade C will remove the cloudy/hazy white background (called “undercast”) and other surface dullness found in many otherwise good polish finishes. (See Specific Procedures)
NuShine Grade G6 – When the surface has not been polished, or has been allowed to deteriorate, G6 may be a good answer as it will quickly but gently get to a “healed” surface finish. G6 has a high-tech abrasive system that is designed to do a quick, aggressive oxidation cut, and immediately break down to a finer cut, similar to Grade C. Use when there is normal to serious oxidation on the surface of the aluminum, or even when very light surface marks are evident. Can also be used to blend light surface scratches in aluminum and will polish stainless steel.
NuShine II Grade F7 – F7 has a very hard and sharp, but very fine abrasive that continues its compounding action throughout the buffing process. It is best used for blending very light pitting or scratches from aluminum surfaces, polishing new, non-clad, cast, or forged, smooth surface aluminum, or for polishing smooth stainless steel or titanium. You can follow F7 with Grade S for final finish without intermediate steps.
NuShine II Grade F9 –F9 is used on non-clad aluminum, SS and where the surface has been damaged by corrosion, has severe pitting, or has had severe stripping processes, including being sanded or scratched by abrasive cloth. Ask your Nuvite representative for specific recommendations, but never use standard commercial grade sanding papers –even wet, on aluminum to be polished. Alternatively, there are specialty micro fine surface sanding materials (specialty grade abrasives –not commercial grade sandpapers) that may be helpful in really severe situations prior to using F9. But F9 is a good surface blender and is useful even for non-clad aluminum, forged and cast aluminum, stainless steel and titanium and anodized surfaces needing special procedures because of the surface hardness. Usually it is necessary to follow Grade F9 on aluminum with Grade G6 or C for further surface preparation prior to final finishing with Grade S.
Recommended Equipment for Polishing:
For compounding the surface:
-- An inexpensive electric variable speed circular buffer/polisher (normally called a “car" buffer and can be purchased from Nuvite - #EQ-136or at most discount department stores)
NOTE: no more than 1500 - 2000 rpm should be used.
--Purchase a “Velcro” mount buffing head (from Nuvite #EQ-143or use the 3M “Hookit” System) for the above buffer/polisher if it does not come with Velcro-type backing pad.
-- Nuvite #EQ-140or 3M #05711, 05719 (or equivalent) TUFTED wool (looks like carpet - look for “twilled up” tufts of wool hair –not loose wool hairs) may say: "Compounding Pad" - for the buffing head and a buffing "spur" (pad conditioner to prevent matting -Nuvite #EQ-144). Pads can be cleaned, washed and reused.
For Finishing the Surface:
-- For finishing, one of the best machines we have seen is the Cyclo Model 5 dual head orbital buffer - Nuvite #EQ-136. The Cyclo will do a better job, faster and will be easier to use than almost any other buffer we’ve found –an important consideration for the future upkeep of your polish job. It is used in combination with the cotton flannel sheeting below to get the swirl-free, absolute mirror finish. Foam pads are used only as a drive surface for the cotton
flannel, which is wrapped across the face of the pads. (See Specific Procedures)
-- Cotton flannel - Nuvite #EQ-145to wrap around orbital buffing head for finishing.
Another, somewhat less effective option for final fish polishing is an electric orbital (non-spinning pad) auto polisher, that can be found at any large retail auto supply store. It is less expensive, and will take more time and work, but it will do the job.
Nuvite Recommended Polishing Procedures
for NuShine II Metal Polish
Procedures for polishing non-clad aluminum sheet metal, i.e., Sonex, Zenith, Murphy and other kit aircraft and other vehicles using nonclad, mill-finish 6061 aluminum, as well as cast and forged aluminum..
The following method using Nuvite NuShine II Metal Polishes will polish non-clad aluminum sheet stock, giving you an outstanding finish and a show-quality shine. There are several popular kit airplanes designed for and built from 6061 non-clad aluminum sheet stock.
However, almost by definition, this means it is “mill finish”, and to get a good final finish, it requires some special, time-consuming -but not “hard” work. This is because mill finish is often rougher, but also, when you polish the actual alloy, you are working with a much harder surface than would be the case if you were polishing clad material, which is soft.
The good news is that once polished, the non-clad stock will resist dulling from atmospheric oxidation much longer than does clad material! Our experience with non-clad material polished as follows has been excellent. You just have to spend the unneeded future upkeep time up front – but since you are building, it can be an easier task to get at the surface for polishing.
Nuvite NuShine II metal polishes are manufactured in various grades to match the needs of the original metal condition in the compounding phase of polishing. This system makes it ideal to deal with non-clad, mill-finish aluminum sheet stock. Following the use of a compounding grade of NuShine II polish, the final finish is always done with NuShine II Grade S that gives you that really bright, fine and deep image, with no machine swirl marks.
The mill finish usually means that there are fine surface lines over the whole surface from the rollers that formed the sheet. Because Nuvite NuShine II is a "blending" type of polish (does not grind away the rough spots as other kinds of polishes do), the compounding phase is meant to merely roll the microscopic high spots and low spots together into a smoother and more reflective surface. We call it "healing the surface". Once this compounding phase is complete, the lines, or “grain” will be minimized or smoothed altogether, and the surface is ready to take a high and deeply transparent shine with an excellent, mirror-like image reflectivity.
Specific Procedures::
Compounding Phase
F9 Passes
Assure that the surface to be buffed is clean, dry and free from oils & water.
1. Using Nuvite NuShine II Grade F9, put big wet “fingerprints” of polish every 3” over a 2’ X 1 ½’ area to be compounded. Compound buff using a variable speed circular (“car”) buffer and 100 % wool “compounding” pad. (Nuvite EQ-140 or 3M #05711). “Compounding” pads can be identified by the tufted pad face that is “twilled” into tufts, similar to a cut-pile carpet. VERY IMPORTANT: Do not use standard “loose wool” pads.
2. “Pat” the surface with the pad before turning on the buffer to spread the polish a little so it will not “throw” when the buffer is turned on. Turn on the buffer at about 1500-2000 rpm and buff across the surface, holding the buffer at about a 15 degree angle, so that one side of the buffing face of the pad comes in contact with the surface. Do not hold flat. Move the buffer back and forth over the area with sweeping passes. About 2 to 3 seconds per foot seems to work well as a starting suggestion. Some pressurecan be placed on the buffing, but keep the buffer moving to prevent overheating the surface. Do not slowly “grind” across the surface. Moving slowly, especially when the surface is still relatively rough, can cause overheating both the metal and the polish. Due to surface friction, heating occurs rapidly during the first pass on the mill finish. Do not keep buffing after the metal stays too hot to touch for longer than 10 seconds or so. Move to the next area, and after a couple of passes there, return to the first area after it has cooled. As the surface gets smoother, heat does not build as fast. To control heating, maintain the “sweeping” action across the surface. Do not stop and “work” a spot. The surface will get hot as you buff, but will cool quickly as you move over other areas being worked.
3. In 45 to 60 seconds, the black polish residue should come off the surface, leaving a clean, clear surface. If the black residue remains on the surface longer than 60 seconds, too much polish is being used, and the desired surface blending action is reduced. You may wish to continue working the surface a little while after the surface is clear, as the F9 is on the pad and will continue working for another 30 seconds or so.
4. Repeat the above over the same area. The more passes, the more the blending action will ease the mill roller “grain” and smooth the metal surface. We recommend four to five passes as a minimum. Each pass runs only a bit more than 60 seconds, so we are not talking an all-day project for each small area. More passes will give a smoother surface, although even more passes will not harm the metal or its’ properties. Do not allow your pads to load up (get shiny). Use a spur to refluff the pad nap about every 15 minutes. Change pads when it will not refluff the wool pile.
As a suggestion, areas that will be out of sight –top of wings on a high wing plane, bottom on low wing, and the belly, will look great after two passes, while “high-visibility” areas, such as underside of the wing (high wing – top surface of a low wing) and the fuselage turtledeck, cowl & sides get more, if necessary, passes to get that extra, up-close, smooth finish.
After working one area, move on to the next area, and so on. When through with buffing for the day, thoroughly clean the surface of any F9 polish residue around fasteners/seams/ joints, etc. Long nap microfiber cloth is very effective
5. when polish is still fresh, and seems to have an affinity for the accumulated polish. Leaving the polish to dry makes the residue harder to remove, and may require mineral spirits.
Grade C Passes
Follow the above with a second phase of compound buffing, this time two passes only, using identical procedures, with Nuvite NuShine II Grade C. This double pass with C will brighten the surface color to a high, bright shine, but polishing marks on the surface will be visible. These are taken out with the final finish pass. Use fresh buffing pads (not impregnated with F9 polish). It is always wise to mark pads to keep the process organized so that a stronger grade polish is not introduced during compounding with a finer grade (i.e., later in the process).
When polishing a kit type aircraft, we recommend that at least the compounding polishing should be done before assembly – on a padded bench or similar such as an assembly jig, so that overhead and “lying down” polishing effort is avoided. Completing the compounding phase while unassembled and doing the final finish after assembly will minimize the muscle strains.
Also, another recommendation: Do the “Compounding Phase” –F9 passes and the C passes, cleaning up rivet residue, etc. as you go. Then stop polishing and complete your plane – assembly, details, and fly off the hours. When the heavy “tweaking activity” is done, then go back for a touchup in those areas you have messed up with a pass of Grade C, clean up the residue, and then do the final finishing. This way, your final finish will not get damaged with the assembly and flyoff time activity, so you don’t waste effort.
And finally, -consider: some folks feel that most kit aircraft sit so low to the ground that nobody, but nobody, can see that your polish job isn’t perfect on the bottom side. Besides, when you have to rebuff…, well let’s just say buffing on overhead surfaces are somewhat less than a fun time… If you agree with this (you might even work your paint trim scheme to paint the cowl and belly/bottom of the wing…!) spend your effort to get the highly visible areas looking really good –the top of the wings (low wing), turtledeck, tail, etc., and leave some of the mill marks in, -but brightly polished - on the underside. Guaranteed it will look perfect at pattern altitude!
Final Finish
1. Using an orbital buffer, such as the Cyclo Model 5 (Nuvite EQ-137) with a 100% cotton flannel sheet (cotton “sweatshirt” material -Nuvite EQ-145) merely held tightly wrapped over the orbiting pads with your hand, final buff with Nuvite NuShine II Grade S. Orbital buffer pads do not turn (not powered), only “orbit”, so you are just buffing through the flannel.
It is very important to keep the flannel sheet face clean. Fold sheets face-to-face for stock storage. When using in the polishing environment, make sure that the flannel “fleece” or polishing face side only comes in contact with surfaces that are clean and free from any earlier polishing residue. An easy way to insure that the flannel fleece is not contaminated with dirt and dust is to use a roll of “butcher paper” and unroll a clean sheet each time for the flannel face to lay on when wrapping around the buffing head(s).
2. Put one wet “fingerprint” every 6” over 2’ X 1 ½’ area. Buff with continuously
moving sweeping action. Do not slowly “grind” across the surface. Polish residue should disappear after 30-60 seconds. Buff until surface is clear and clean of polish.3. Move on to the next area, and so on. “Clean buff” – use a lightly used flannel spot over the buffing head(s) and spot buff any leftover polish residue areas. Follow with a “dry” pass (no polish) with long, wide buffing sweeps, using a clean long nap microfiber cloth for final surface cleanup.
Although this polishing can be as much of an intense process as preparing the airframe metal for painting might be, you will find that once done, the shine and longevity of the polished non-clad material is exceptionally good. Quite a bit better than with aircraft built of clad material, although they will get better over the years as they are buffed over and over until the clad is burnished smooth and “tight” with no oxidation on the surface.
For most homebuilt, all metal, 2-passenger size aircraft, you will need approximately 2 to 3 pounds of Nuvite NuShine II Grade F9, 1 pound of Nuvite NuShine II Grade C and 1/2 pound of Nuvite NuShine II Grade S to accomplish the process as described above.
We have had reports that the polish on non-clad aircraft is not affected when wipedown, debugging and cleaning with normal wetwash cleaners such as Nuvite CitriCut, using standard dilution as directed. Do not allow CitriCut or any other citrus-type cleaners to contact your polycarbonate windscreens or side windows, however. They are not approved for polycarbonates such as “Lexan”. For acrylics such as Plexiglas, CitriCut is tested and certified for use.
Polishing has its’ advantages. It is likely you will spend a great deal less than the cost of the paint, primer labor and other materials, there are reports that the needed surface preparation for painting does not take a great deal less time ($$$) and effort than this polishing process!
And, of course, your aircraft will be lighter…
Another consideration is that you will most likely find the grass around your airplane to suffer greatly more traffic damage at airshows than others.
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