Polishing mini tutorial

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Naiveambition

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I've been polishing on and off for a while now and thought I would throw some info to those in need. I usually start with 400 grit wet sand if the nicks aren't bad, this is also where most rouge will produce a good shine. But it can be better

After u have an even surface while sanding in one direction, or back and forth, don't just do random spins. After 400, go 600 and change direction of your sanding, once all of the opposite scratches are gone you can switch to the following grit. I usually go straight to 1200 from here, by now it should be producing a nice shine. The sanding is a little tiresome on the small parts, but this also will produce nice clean edges and less buffing time for rounded corners.

The rouge I use generally is the green stick rouge. Eastwood , and truck stops, have them. A liquid green one is also very good. It considered jewel ears rouge I believe. Use a Cotton buffing wheel on a good drill, load up the wheel. Don't be shy get it on there. Then start working your peice back and forth.try to move in even, parallel lines for bigger pieces. The wheel cuts more one way than the other , depending on your movement. The color stroke is the last ones where you feed in one direction only . Clockwise rotation with left to right feed. Hope that makes sense.

Use a fresh cotton wheel with different rouges. Never mix them

Finish off with white rouge. This is where it gets really nice. Same thing don't be afraid to load up the wheel. Once it reaches enough polish it will become rather easy to make it really shine.
This way is far superior to just using mothers style polishes. Most all steels and aluminum will look chromed.

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Straight from turning on lathe. When doing cylinders I Try to spin them using a flat peice of metal, wood, wrapped in sandpaper here is before

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Figured I would add a little to this thread, If anyone has ?s , feel free to ask

Although this is not an engine, it does show the process. Most metals have a certain rouge for them, like stainless, copper, brass, etc. what I've attempted to show here is a kinda catch all formula.

First pic is just receiving the knife.

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First step was file work. I like to use files since thy produce a even flat surface.
I used the draw file technique on this peice. For those that don't know it's turning the file sideways and drawing torward you. Keep the file clean, clean, clean at all times. Often produces a better finish than sandpaper. Sandpaper tends to round the edges if u r not careful. I use a small peice of metal wrapped with sandpaper to keep a flat surface, your fingers will make valleys:wall:

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Next stop was sanding , starting with 320, 500, 600, and finishing with 1200.

The hard part is getting to 320. Once your there all your grit changes are much faster. Again, always try to change directions after each grit. Here's the 1200 result. Notice the shine is almost there. The rouge starts really bout 500 grit, so when buffing , keep moving, and it will take out some good scratches. But I like to sand a little more than just rely on the polishing. It cuts my time down polishing, and helps me control the rounded edges.

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And here's the finished pic.
Sorry for the multiple posts. My iPad seems to only allow one pic per post.

Here I'm using green jewelers rouge. I have two styles . One liquid and the dry bar. Both work the same just a little more work to load the pad when dry. When you have too much it will start leaving black patches on your work. Stop and remove them, then continue. .

After that finished off with white rouge. This is the super shine. Here I like to really be aggressive with the amount of rouge. I load quite often till I se al light greasy film cover the piece. This is the rouge working. When you lose it , you need to reload.

I think the handle is sterling silver cast around the blade, the shank I think is steel. May be stainless but can't tell for sure.

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Polishing a second Poppin and thought I would post my work here to help out the thread. Started with a fine file to remove all the nicks and machining marks. Then moved to 325 grit sandpaper wrapped in a Popsicle stick. Both for flatness and getting where my fingers are to large. Finished up with 500gr wet sand. Polishing was done on the drill mounted in the vise. Hard cotton buff with green jewelers rouge. I have a regular polisher that's 2 horsepower that does a awesome job, but I literally am scared of it. It's so strong, u will not stop it. With the drill I have a little more control and less chance of the part flinging off across the room.View attachment ImageUploadedByModel Engines1422401756.855821.jpgView attachment ImageUploadedByModel Engines1422401774.312211.jpgView attachment ImageUploadedByModel Engines1422401796.600753.jpg
 
Nice job on the tutorial. Very good point in changing directions with grits. I spent a lot of times polishing hardened tool steel for molds and it was the one part of moldmaking I hated!
A good trick to see how flat a polish is get a reflection of a pair of flourecent tubes in the polished surface. Any out of flatness shows up like a beacon.

John
 
Polishing a second Poppin and thought I would post my work here to help out the thread. Started with a fine file to remove all the nicks and machining marks. Then moved to 325 grit sandpaper wrapped in a Popsicle stick. Both for flatness and getting where my fingers are to large. Finished up with 500gr wet sand. Polishing was done on the drill mounted in the vise. Hard cotton buff with green jewelers rouge. I have a regular polisher that's 2 horsepower that does a awesome job, but I literally am scared of it. It's so strong, u will not stop it. With the drill I have a little more control and less chance of the part flinging off across the room.View attachment 74628View attachment 74629View attachment 74630


Polishers/buffers are nothing to mess around with! I just read an article that a custom knife maker was killed while using one last year. Apparently the knife caught and was flung right into his chest area. I don't want to drag the thread off topic but if you are using any sort of buffer please take care and use the safest approach possible.
 
I agree hole heartily with safety issues. I'm not to keen on polishing knives. My brother inlaw is the knife guy that's buying em up and has me polish a few.

Fluorescent lites are a bittersweet combination when it comes to buffing it seems to me. While. They are great for showing imperfections, they will often show every imperfection to the point of trying repeatedly to make a better finish. Whereas under garage lights it will look rough, but in sunlight it will be impressive.

I once polished a pair of stainless rocker panels for an old 65 Pontiac GTO., the ones that run under the door and between the wheel wells. The guy was pressing me to get them done and I was still not happy seeing lite swirl marks, in the garage. I give the pair back with what I thought was the best it's gonna get. Later, I saw the car at a car show and I was blowed away with how great they looked in natural light. Customer happy, made no money, I was learning then and charged a 100$. Should of been 600$. Had to all be sanded by hand , due to a slight bow in the peice.
Later he asked if I wanted to do a whole engine block for a open 30's hot rod coupe. After the hours of sanding the panels, I'm thinking" I don't know if I wanna see you again" haha
View attachment ImageUploadedByModel Engines1422643188.617385.jpgView attachment ImageUploadedByModel Engines1422643203.414236.jpgView attachment ImageUploadedByModel Engines1422643218.619695.jpgView attachment ImageUploadedByModel Engines1422643235.723581.jpg
Anyways here's a few pics of the Poppin. Finished polishing other parts , while waiting for paint to dry on flywheels.
 
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