Topic: My experience with parts polishing (pictures attached)

[Raul CB750K1]

I had one week holiday so I had some time to spend on the shop. I'm waiting for Cheapo's camshaft so it was time to try the polishing.

I have polished all the "Boat Anchor" CB350 engine covers and the result is simply outstanding. First of all, with a dry metal sandpaper, I sanded off the deep scratches, in parallel and perpendicular to the scratches. Once the surface was level, I used wet sandpaper in grades 180, 360 and 500. First 180, hot water and dishwashing liquid, and sanding in just one direction. Rinsing, 360 sandpaper, hot water and dishwashing liquid, and sanding in perpendicular, and finally 500, hot water and soap, and sanding in swirls. I must say that it didn't take more than 3 minutes each grade, just do it until you feel the sandpaper is worn out and you are rubbing just paper. (the sandpaper only where there are scratches, otherwise, just the buffing wheel)

Then, the buffing wheel. First, the sisal weel and the brown paste, and then the cotton wheel and the blue paste. Here you have some pics; if you like them please applaud me because my wife didn't got much impressed... ;-)

A word of caution; the buffing wheel throws a lot of aluminium dust. Wear googles, breathing mask, and get ready to sweep and dust off all the shop afterwards. The aluminium dust gets into the skin and hair too and you will have to get a good shower after that.

Raul

[Raul CB750K1]

More pictures...

[Raul CB750K1]

...and the last ones...

[Paul]

F... !
Applaud

[csendker]

Then, the buffing wheel. First, the sisal weel and the brown paste, and then the cotton wheel and the blue paste.

I'm looking to polish up a couple of parts, and your's look fantastic.  I don't have any scratches, so I shouldn't need the sandpaper part.  But what the heck is a sisal wheel?  And what are the pastes?

[martini]

Awesome, nice work!

I wouldn't have thought you could get scratches like that out, gives me hope for my 350F project.

Its amazing how this kind of thing always fails to impress the spouse.

[Raul CB750K1]

Awesome, nice work!

I wouldn't have thought you could get scratches like that out, gives me hope for my 350F project.

Its amazing how this kind of thing always fails to impress the spouse.

That's what I thought, that those parts were for the scrap. For that reason I bought new ones -used- off eBay. One of them had been polished and looked much better than mine, so, as I had nothing to lose, I decided to give it a try. Believe it or not, my parts are now much, much better than the ones I bought off eBay. And it feels really good when you are really RESTORING a bike, that is, using as many original parts as possible. There is nothing thrilling in replacing parts unless they are hard to come by like Kawa parts. With old Honda parts, if you lose an auction you can always win another one next week. I really feel good being able to reuse the original parts, though I've already stated that I don't think any part is "original" as long as it was chosen at random by the factory line operator.

I also polished the top engine cover. The buffing wheel didn't get easily in one of the grooves, and as it is not seen, I just left it like it was -after cleaning with degreaser-. Check the difference out!!!

[Raul CB750K1]

Some pictures after the sisal wheel and before the cotton wheel, and the "before" and "after". I decided to let those tiny scratches on the logo stay, because they are very hard to notice and also because I didn't want to ruin the logo. They bear witness that we are talking about the same piece.


You can see the reflection of the ceiling light tube. That blueish colour of the last pictures are because they were taken outside and it was cloudy. The problem with pictures of shiny objects is that if you use the flash they come out bad. If you are perpendicular you get your reflection pictured, so I took them out because, having enough light, the flash was not needed.

[MRieck]

Nice work sir. I leave the polishing to a friend of mine...it's too much work!! 

[Bob Wessner]

Looks like you repainted the background on the piece with "Honda" in relief. Did you do that by hand?

Nice job by the way. 

[Raul CB750K1]

Looks like you repainted the background on the piece with "Honda" in relief. Did you do that by hand?

Nice job by the way.

No, it was already painted, I believe it came out from the factory that way.

Actually, I was afraid because I thought the buffing wheel would remove the paint so I would have to repaint it and I don't have such a firm hand. But it turned out that the wheel only remove the outer paint, leaving a shadow on the letter's sides and the grooves, so I will leave it like that.

[bill440cars]

Out standing job!!  As state by others, it sure gives others of us hope. I've got some that are going to take alot of work but, when I see what you did with what you had, I feel like I've got a chance. You definately deserve an applaud (one right after another)   Bill

[MetalHead550]

Its alright, Im pretty sure women make as little sense to themselves as they do to us  .  Nice work.  Expound upon the brands/types of buffing wheels and pastes you used.  I plan to polish the cases on my 75 when the time comes for an overhaul.

[Geeto67]

Then, the buffing wheel. First, the sisal weel and the brown paste, and then the cotton wheel and the blue paste.

I'm looking to polish up a couple of parts, and your's look fantastic.  I don't have any scratches, so I shouldn't need the sandpaper part.  But what the heck is a sisal wheel?  And what are the pastes?

For any polishing job you will need to wet sand with at least 300 grit paper, reguardless of scratches. It is just the best way to get a good even mirror like surface and not one that is wavy. When sanding use a sanding block and becareful not to take the sharpness off edges.

A sisial wheel or Sisal Buff is a flap style buffing wheel. It is a deep cutting wheel that lays down the foundation for a good buff. Go to any store that sells buffing supplies and ask for a sisal wheel, they will know what you are talking about. The pastes are probably different grades of jewlers rouge or polishing compound. Eastwood sells a good kit, home depot occasionally sells jewlers rouge.

[Raul CB750K1]

. You definately deserve an applaud (one right after another)   Bill

I was not talking about virtual applause!!!! click on the [applaud] link besides my avatar!!!! I want to get 100 of Karma so I can beg Glenn to promote me as moderator so I can delete Terry's posts at will   HA HA HA HA Cheers Raul    Ooooops, I'm becoming very influenced.....

. Expound upon the brands/types of buffing wheels and pastes you used. I plan to polish the cases on my 75 when the time comes for an overhaul.

I used german-made Wolfcraft wheels and pastes. Probably not available in US, but any brand will make, there is not a high technology on it.

http://www.wolfcraft.de/en/produkte/products/master7a19.html?countryID=EU&languageID=en&wo=EU&dataLang=en&pub=&cat=catalogue&prdGrpID=050108&KSchrift=&KSchrift_languageID=&priceList=

I bought a set like this one, about 11 euros, and a set of wax bars. The wheels are pretty much worn out, so I can say it took 11 euros and about 8 hours to polish all the parts, plus the electricity used for the hand drill. I put it on a bench support and applied the part to it. As the paste has the polishing compound mixed with wax, I noticed that the warmer the part gets, the better the result, because the wax tended to become hard in contact with the cold -indeed cold- part. There are some other parts that doesn't appear on the pictures.

For any polishing job you will need to wet sand with at least 300 grit paper, reguardless of scratches. It is just the best way to get a good even mirror like surface and not one that is wavy. When sanding use a sanding block and becareful not to take the sharpness off edges.

I agree with that, though the only parts I wet sanded were the ones with scratches and I cannot tell the difference in brightness; they look the same. But wet sanding won't hurt and will remove much of the grit, leaving less work to do for the buffing wheels. I also commented a while back that the parts where painted, so I used gasket remover first. It simply thins out the paint, again leaving less work to do for the buffing wheel. The problem with gasket remover or paint remover is that is highly corrosive so you have to handle it with care.

Raul

[Raul CB750K1]

Check the setup out. Look at the dust in the floor, and I was only halfway. The clutch cover took a good hour alone, as it took a lot of time to warm up and also it has a lot of ribs and valleys (nooks and crannies). You have to be very careful to avoid scratching the part with the drill mandrel or the wheel mounting bolt. It is a "counter bolt" to avoid it loosening when turning in the drill. Anyway, I kept removing the wheel every now and then and turning it, because the strands tend to bend in the rotating direction. If you turn the wheel the strands become more "aggresive". Because of the "counter bolt" I couldn't simply reverse the rotating direction of the drill.

Raul

[Raul CB750K1]

Regarding the setup, I'm ashamed to recognize this, but I bought that drill only for this purpouse to avoid my drill becoming dirty. The polishing kit costed about 11 euro, the drill support costed about 9 euro, and the drill costed....... 5.99 euro, inside a custom-made plastic suitcase, with a spare set of brushes, a hand bracket, and a depth meter. 13 mm maximum bit size, keyless mandrel, 800 W with hammer function, reversible and electronic variable speed. These chinese people are going to blow the market away!!!!!

Raul

[Geeto67]

The brightness will be the same no matter what, the evenness of the panel being buffed will be different. When these parts were cast little though was given to how flat the flat surfaces actual are since they didn;t think anybody would notice. However if you don't sand 1) you are polishing through the top layer of protectant chemicals (ie clearcoat) that will not polish no matter what you do, and 2) you are not leveling the surface so you may get things like ripples in the finished piece. When I first stated polishing stuff I never noticed the unevenness of the castings but over time I came to see it and now I can really spot the difference between a good job and a bad one even though both will have a mirror shine.

I think you did a fine job Raul. Looks excellent.

As far as protection, wear clothes you don't like when polishing and always wear a mask. The stuff gets so fine in the air that if you don't you could end up with silicosis (similar to asbestosis). Also the fine particles are flamible (eg flour bomb) so always work in a ventliated area.

TO avoid a grain in your work always polish in different direction when making a pass. Helps to even out the piece also.

[Raul CB750K1]

I think you did a fine job Raul. Looks excellent.

I understood that your point was not to rain in my parade but to be helpful, you didn't need to add that comment but I appreciate it. ;-) Anyway, I'm not looking for virtual applause, I'm looking to increase my karma!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You are right regarding the clearcoat, but as I said, I used gasket remover before, so there were no traces of clearcoat or enamel. I also have to admit that, though the result was great to my eye, I know it will dull in some months, so I really didn't do all my best with it. I think that, even when the mirror shine is gone and a dull finish sets on the surface, it still will look better than before, and that will be enough for me.

Raul

[Jonesy]

Nice work, Raul... I applaud you! (Wish someone would bump up my karma a bit!)

I had similar results with the alternator covers on my 750. The darkening you are seeing around the "HONDA" on the cover could be residue from the polishing. After I polished parts I had to clean off the excess compound, revealing a beautiful finish underneath. I'm sure you could get some black enamel paint and fill in the recess behind the logo. The trick is to thin the paint down to where it just flows into the recess, filling in all the depressions. It takes a long time to dry, but it will look nice when finished.

For the general questions in regard to the compounds used, here's what I've learned:

Most sticks of polishing compound are sold in sets of 4 grades:

1) Black Emery Cake. This is the most abrasive. This is good for removing small scratches and surface imperfections.

2) Tripoli Brown. This is more of a medium-grade compound. It will remove wheel marks from a coarse wheel or compound.

3) Red Rouge. This is a fine compound that provides a bright, clear finish.

4) White Rouge. This is an extremely fine abrasive. I find it good if you want an absolutely perfect finish.

There are also different grades of buffing wheels. There is the sisal type, as Raul mentioned. There are also coarse and fine cotton wheels, with varying types of stitching. Finally, there are felt wheels. I find them good for mild polishes, like red or white rouge.

One thing that's getting hard to find is a wheel rake. This tool dresses the wheel, cutting down any stray threads and it removes the previous polishing compound when you're ready to go to another grade. It's a bit of a pain, but I like to have a wheel for each compound, rather than get compounds mixed up. (But, I do a LOT more polishing than most folks, doing restoration work, so this is overkill for some)

Some guys like to take the buffing wheel setup outside, between the dust and the "fuzzies" that come off the wheel. The mess is easier to clean, and you stay cleaner, too!

[Raul CB750K1]

One thing that's getting hard to find is a wheel rake. This tool dresses the wheel, cutting down any stray threads and it removes the previous polishing compound when you're ready to go to another grade. It's a bit of a pain, but I like to have a wheel for each compound, rather than get compounds mixed up. (But, I do a LOT more polishing than most folks, doing restoration work, so this is overkill for some)

I agree with that. The wheel got clogged with crap, a mixture of dust and wax, so it becomes unefficient. You have to clean it every now and then (I used an old hacksaw blade).

[Jonesy]

Yep, that's exactly the problem. (Clogged wheel) The hacksaw blade works good. Wheel rakes are hard to come by. I walk into a tool shop and ask for one and I get blank looks....

[Bob Wessner]

Hey Dan,

Is the $$ for this worth the difference between it and a hacksaw blade? Never used one so I don't know.

http://www.stewmac.com/shop/Finishing_supplies/Abrasives,_polishes/Buffing_Wheel_Rake.html

[Jonesy]

You beat me to looking one up! ( was going to do this when I got home from work...)

The hacksaw blade can be a bit dicey, as it could be harder to hang on to. Anything with teeth the wheel will want to grab and throw it. The rake also has deeper teeth to dig further into the wheel. I've never done a head-to-head comparison. Next time I polish some stuff I'll report the results. I have a brass propeller that needs spiffing up...

[78 k550]

sweet finish. I'm going for that look also. I hope it is a good as this.
Fantastic job.

Paul