Front Drum Surface Finsih

[billpedalino]

I'm restoring the front wheel on my 1964 CH. In looking at the finish on the left side of the brake drum, I recall how these drums looked when we set them up at the dealership. They had a glossy sliver-grey, not-too-shiney industrial finish - not a polished finish. Also, I remember wondering how that bare aluminum finish would hold up and surmised that it might have been factory-coated.

Now many years later, after polishing a small sample surface on another drum, it appears that there actually is a coating. However, despite this coating all of the front drums that I have are oxidized and I would like to reproduce that original factory patina. To that end, I have three questions:

1. Does anyone have experience in returning this finish close to that from the factory and if so, what did you use to do so?
2. Does anyone know what the factory coated these drums with?
3. I'm told that clear powder coating works well in holding a new finish on aluminum. I generally don't use powder coating. Has anyone used this and if so, how well does it work and does it yellow over time?

Thanks,
Bill Pedalino

[Chris Haynes]

The aluminum drums were anodized. Polishing removes the anodizing and they will dull.

[billpedalino]

Thanks Chris.

Well, all of the drums that I have now are dull anyway. Eventually Oxygen finds its way through the coating and does its magic.

After you Identified the surface treatment and after looking at the 'coating' again, I now recognize it as anodizing. Anodizing was a very common process here on Long Island back in the local aircraft industry days up to the late 1960's/early 1970's. But it is still farily common here so I can have the drum anodized. I'm thinking of etching it first to try to re-gain the original color, then anodize. Have you had any luck with clear powder coating? I'm told it holds the finish well, but I'm concerned about yellowing over time.

[dlxl66elxl]

You may want to have the drum, front and rear brake plates and alloy rims polished prior to anodize. I'm doubtful if HD did anodize as they 1) were rather frugal in terms of production costs and 2) didn't care much about long term appearance (i.e. fading HiFi colors). As an alternative, I use a product from POR 15, Glisten PC to coat the polished aluminum. My polisher "over does it", but I don't have the heart to tell him "too good". That product has you applying a mild acid solution to etch the surface prior to applying the two part product. Be sure to do it in a clean environment as it dries slowly. I have coated several Sportster rims and brake assemblies with excellent results, plus the coating prevents long term oxidation. I used to use Eastwoods Nylac, but hat is no longer available. Their current product (Diamond Coat, I believe) peels off easily. Others have also reported this problem. Good luck

[billpedalino]

EXCELLENT information DLX .. and I haven't the heart to criticize my platers over-luster polishing as well! The coating on the drum does appear to be anodzing or some other material, but it's definately coated. I also have early aluminum rims for this bike which, given my other bikes, I'm not looking forward to maintaining, even with the bike just sitting in my basement. I intended to use the Strong Arm spray to try to keep the oxidation rate down, but the POR 15 product sounds like a better soultion. Have you experienced the long-term performance of the POR 15 yet?

[dlxl66elxl]

You might check the POR 15 web site for any long term degradation in the product. The Nylac product held up very well. The following link is to a bike I did 20 years ago with Nylac and its holding up well. http://www.harleykmodel.com/gallery/...lch/index.html

[billpedalino]

That '66 brought back many memories. Outstanding work! Thank you for sharing. I ordered the POR 15.

[billpedalino]

Upon closer inspection, I've noted the following:

The front drum that I have is in extremely good condition. If you look closely at the left side, you notice very faint but distinguishable radial machining marks. I now remember these marks on the new Sportsters that we un-crated way back when. Therefore, technically speaking, if you polish these drums you actually sacrifice the original finish for enhanced brightness. Also, in going through the several drums that I have, it looks like the earlier ones were coated (possibly anodized) and the later one appears to not be coated.

Therefore, in an attempt to break my over-analytical and needlessly perplexing tendencies, I'm just going to lightly buff it with a fine polishing compound, apply PORE 15 and be done with it. A command decision has been made!

[billpedalino]

dlx -

I started playing around with the POR-15 material that you suggested above and I must be doing something incorrectly, despite the fact that I'm following the printed instructions closely. Being that you've had success with the POR-15, I'm hoping that you can shed some light here.

I have the above-mentioned front brake drum which I've gingerly polished, but not to a 'show-polish' finish. It looked pretty 'factory' when it was done. In fact, as part of my polishing and cleaning process, I even did a mild muriatic acid etch, followed by polishing with DuPont white compound on a yellow sponge polishing wheel. Nice result. I then thoroughly washed the piece in water and wiped it down with acetone and let it dry, followed by another water-wash and dry. I then sprayed on the POR-15 acid prep and let it stand for about 2 minutes. Here's where things went wrong....

The shiny finish that I had obtained prior to the etching and polishing immediately turned dull and blotchy with areas of a faint tan staining becoming evident. I thought that maybe the application of the Glisten would chemically neutralize the stains and brighten the finish, but it did neither. I only applied one coat the Glisten to two small test areas. After about 25 minutes, it appeared evident that the finish that was seeing was as good as it was going to be, so I wiped off the semi-hardened Glisten with acetone.

Although I didn't see it on this particular drum during the polishing process, I thought that maybe there was some remnants of the anodizing that I did not see which was causing the problem. So I buffed up a section of a rear brake backing plate using the above process and again, as soon as I sprayed on the prep I noticed problems. Although no tan bleed-through, the acid completely dulled and blotched the surface. After rinsing off the prep, I buffed the dulled surface by hand with a clean rag and applied one coat of Glisten to the test area. After 20 minutes, the resulting finish was far inferior to the mildly polished, untreated adjacent areas.

Given the above, what was your process and your experience? Given the photo that you posted, this stuff apparently works well and evidently I'm screwing something up. Can you identify what I'm doing incorrectly?

Thanks...

[dlxl66elxl]

Bill,

I have obtained excellent results shooting the stuff with a HVLP gun (a $10 Harbor Freight touch up gun) at about 12 -15 psi (minimum pressure to flow) with a tack coat and one light wet coat. if you apply too much, it will fish eye. I am in warm and dry southern California. The tack coat needs to set up for however long it takes to tack then hit it with the finish coat. It usually takes several hours to dry so no dirt settles, cover parts after spray. For prep I wash with a degrees-er and spray their acid etch. I am more focused on alloy rims than brake drums and plates. On one test brake plate I set it on the ground and a lizard ran across and got stuck. A new form of modern art.

It sounds like you may have moisture or compressor oil in your air supply causing some blotching. If you are satisfied with the gloss on the brake parts, I would declare victory and abandon the coating or anodize. I have not tried anodize on my over polished rims, but discussed this with a guy who does Japanese bikes and he regularly anodizes to reduce polishing gloss.

Good luck

Dace C

[billpedalino]

Dave,
Thank you for your concise reply. The problem that I'm having has to do with the acid etch prep and not the coating. I've been playing around with a spare early aluminum rim and I'm seeing that it responds to the prep in a much cleaner way than the brake drum and backing plate did, as no blotching appeared on the area that I polished and cleaned, unlike the brake parts. This may have something to do with a 'cleaner' aluminum alloy on the rims, but I'm no metallurgist. Another possibility is that the acetone that I used didn't get all of the polishing debris out of the metal - POR-15 recommends using Xylene so I may do another round of experimentation on the brake parts.

I know it may seem lazy to some, but my concern is the amount of cleaning and polishing of the aluminum parts that accompanies polishing. I own eight bikes at different levels of completion and I work full-time - and I own a house - and I have a wife. It gets a little overwhelming sometimes and my joy of almost 50 years (the bikes - and my wife too!) shouldn't turn into a drudgery. The factory didn't care about this upkeep after the sale as long as the polished parts helped get bikes off of the showroom floor and the dealerships also made a bit of spare change tubes of selling Semi-Chrome polish and cans of Never-Dull. How many electric drills we wore out using those products! Therefore, whatever I can to to minimize the episodic polishing, while not compromising the factory-like appearance would be a bonus in time-saving.

I'm going to talk to my plater about clear anodizing on the front drum and both backing plates as a possible option. Hopefully the anodizing may also have the benefit of 'calming down' his high-luster polishing a little while offering long-term protection. However, I do think that I may try the Glisten on the aluminum rims. I'll report back with my progress.

Thanks again for your advice.

[dlxl66elxl]

Bill,

Always glad to help a fellow enthusiast. I have been into these old XL's since 1966. Ping me at dcarle6596@aol.com and we can share phone info regarding your projects and lessons I have learned, both good and bad. I have restored 13 of these.

Dave

[billpedalino]

Dave,
I wrote this earlier, but it seems to have disappeared during delivery.

We (as well as others on this forum) seem to share the same passion for this niche of our addiction. I remember my first exposure to Harley-Davidson (the exact incident in fact !) in Queens, New York. I was about 5 years old, I sighted my first knucklehead and was immediately and overwhelmingly smitten! When I was in junior high school during the very early chopper years we young, testosterone-driven males certainly appreciated the customs and bobbers of the day, but we wanted to go FAST! We wanted POWER and to us, only the Harley Sportster would fit that bill. In fact, I still own a 77" stroker that I built many years ago while in my 20's. Later on I worked at Harley dealerships and eventually at independent shops as a Harley motor mechanic and during that time, I certainly owned my fair share of Sportsters, Panheads, Knuckleheads and Shovelheads. But the Sportster has, and has always remained nearest and dearest to my heart. I have to laugh when some young non-AMCA type Sunday riders es pout their verbiage about Sportster being 'Girls' bikes or 'Baby/Starter Harleys'. They simply know no better. Back then, with our limited experience and with the impatience of youth tugging at our throttle grips, Sportsters were the cantankerous, nasty, hard-starting, leaky, clutch-slipping, vibrating, beautiful and powerful machines that we couldn't get enough of. People like us, who have actually lived through the development and evolution of this fine machine and the mufti-facited culture that developed around it can fully appreciate these bikes for the the brutally elegant machines-of-the-day that they were.

For fear of further torturing my fellow AMCA forum members to death (thank you all for your endurance and your patience), I will continue this through your AOL email address when time permits. My email address is WMP@Soundindustries.us.

[billpedalino]

I tried the POR-15 Glisten on my aluminum rims with mixed results. Based upon the outcome, I will definitely not use it on the brake drum but rather opt to keep the original finish treated with 'TreeWax' carnuba paste and/or Strong Arm Spray.

I cleaned the newly polished rims thoroughly. Multiple cleanings with Acetone, xylene, and water, followed by a final rinse with distilled water and a thorough drying. I used the acid prep and all looked fine. After a final final rinse I brushed on the Glisten. I used a 'Medium' wet coat which caused a fair amount of pulling on the cheap home depot brush and the inevitable bristle depositing onto the painted surface. As advertised, all brush marks did disappear. After 25 minutes, I applied the second coat. This coat had to go on a bit wetter, as there was even more pull form the first coat.

The resulting finish was indeed very shiny, but not smooth. Small bubble marks appeared in both coats no matter how slowly and carefully I applied the material. I hoped that they would level out as the material set, which they did - somewhat. Also, no matter how hard I tried, I also produced some minor sagging of the applied material. That sucked, as I was very careful to apply it as dry as possible while still allowing it to flow.

In all, the finished product is disappointing to me and I'm pretty sure that it will be a rock-hard nightmare to remove, if I decide to do so. Maybe I could wet sand it after it fully hardens and apply a smoother top coat ? But, their customer service department tells you nothing - they just simply don't respond.

In retrospect, I should have waited until warm weather and fired up the spray gun as, to me, this material screams out for spray-application and POR-15 should tell you that rather than tout how it allows brush marks to disappear. Maybe some of you have had a better experience or are simply better at this than I am. Is so, so be it and I'll concede that point. But I'm fairly good at what I do and in my opinion, a pricy product shouldn't take this much trial-and-error and guesswork for proper application. I can't wait to see the POR-15 guy at his vending booth at Rhinebeck in June for a little 'constructive criticism' ....

[billpedalino]

This conversation seems to have taken another direction so I've updated my experience with POR-15 Glisten under another Thread in the Sportster forum entitled 'Aluminum Rim Finish'.