Tag Archives: Meca Dural

Clear Coating a Vintage Steel Fork

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After much agony, consideration, and research, I decided to clear coat the vintage steel fork from the 1940’s/50’s Mercier Meca Dural bicycle that I have been working on for the past year.

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The fork had been spray painted gray by an amateur over what was rust and pitting on the fork blades.  Purposefully to hide the damage?  Unknown.  Fortunately, steel is forgiving, to a point.  I sanded off the paint and was saddened to see all the damage that could have been avoided had the painter sanded and cleaned the area first prior to painting.

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But, after removing the majority of the rust and pitting, progressively using finer and finer sand paper, I had the fork ready for chrome-plating or painting.  Then came the year-long search for the best plating company or painting company in the area to handle this job.

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This is no ordinary fork.  It is beautifully brazed, with a chrome fork crown and chrome drop outs.  I believe the fork blades originally had been painted grey to match the grey color of the Meca Dural aluminum frame.  The front spacing is 95 mm – consistent with front wheel hubs of that era, and the fork is very light in comparison to modern steel forks.  I definitely wanted to give this fork the benefit of the doubt in terms of restoration.

But after investigating the process used to chrome-plate steel parts, and looking into various chrome-plating services, I was not convinced that fully chroming the fork was the best solution.  I thought about sending the fork out to a reputable painter to have the blades painted grey again.  However, shiny new paint would really detract from the look of this lovely and unique vintage bicycle.  That’s what led me to think about using a clear coat, at least for now, on this pretty fork, especially after my attempts at finding a suitable replacement fork had failed.

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Thanks to many restorers and enthusiasts who have shared their experiences with clear coating steel frames (which is NOT recommended by most builders), I settled on the two key products I would need to finish this job:  MAAS metal polish and ProtectaClear by Everbrite.  By using the MAAS polish, after the final super fine sanding and clean-up, I will be able to avoid the acid neutralization process which is normally required prior to clear coating.  This is because the MAAS polish does not contain acid. 2016-11-15-001

I purchased professional art brushes to help with application of the paint.  In the next post, I’ll share the end result.

Stronglight Competition Headset

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While problem solving a fork issue on the 1940’s/50’s Mercier Meca Dural that I have been restoring, I thought about changing its headset so that I could mount a different fork with a slightly shorter steerer tube.

That effort was, sadly, unsuccessful.  But in the process, I had to compare various French headsets that I had on hand to determine which one might solve the problem of needing a slightly shorter stack height.

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1950’s Stronglight Competition Headset

One of the headsets in my bin was a 1950’s Stronglight Competition headset.  The rest of the French headsets I had one hand were 1970’s French headsets – probably all of which were made by Stronglight, but which are unbranded.  When I began comparing this older headset to the (relatively) newer ones, I was amazed at the difference in quality.

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1950’s Stronglight Competition headset cups and cones

The cups and races are beautifully machined, and are of much higher quality than the their 1970’s counterparts, shown below.

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French headset – 1970’s

The photos don’t quite do justice to the quality differential.  But, if you hold these cups and races in your hands and look at them with bare eyes, the difference is clear.  According to this helpful post from Classic Lightweights, the 1950’s Competition headset is made from hardened chrome nickel steel, and feature V shaped races which provide for more bearing contact (thanks to Jim at Bertin Classic Bicycles for clarifying this important distinction).  The newer 1970’s versions are made from lower grade steel, and have U shaped bearing races.

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The nice branding on all of the pieces really motivated me to try to make this headset work on my restoration project.

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Peugeot fork – 1970’s – looks great on the Mercier Meca Dural frame

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Original Mercier steel fork on the right, Peugeot fork on the left

The original fork was seriously compromised with rusting and pitting on the fork blades.  I had sanded off the pitting and have been searching for the right solution which would result in either an original newly chromed fork, or an original newly painted fork.  I was not able to find any painter or chrome-plater in the Portland region that I wanted to trust with this vintage fork.  So, I looked around at the forks I had on hand.  One of them was a 1970’s fork from a silver Peugeot.  The steerer tube was shorter than the original fork by about 5 mm.  Drinking some Kool-Aid, I decided that maybe I could make this work, after all, the fork looked perfect with the Meca Dural aluminum frame, as you can see from the above photo.

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After doing a bit of research, I determined that I could eliminate the lock washer and instead apply some Locktite to the steerer threads.  That would save about 2 or 3 mm.  But, to make this work I needed to Dremel off the pin on the top of the 1970’s headset that I originally envisioned as my solution to the problem.  Okay, that was easy.

Unfortunately, when I dry mounted the fork into the headtube, I forgot about the space that the 5/32 inch bearings would need.  So, I ended up with only 2 or 3 threads showing on the steerer tube above the upper cup, after installing the bearings.  That’s not enough.  You really need at least 5 or 6 threads showing in order to feel confident that the steerer tube will stay in adjustment, especially if you are going to remove the lock washer.

So, it’s back to the drawing board with the fork.  I either need to find an appropriate replacement fork, or the right company to chrome-plate or paint the original fork so that the bike can be restored to its original glory.  But, the 1950’s Stronglight Competition headset gives further evidence to the quality of vintage cycling components as compared to their modern day counterparts.

Removing Paint from a Bicycle Frame the Safe(r) Way

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Mercier fork

The 1940’s/50’s Meca Dural bicycle that I am currently restoring had an unfortunate encounter with an amateur spray painter.  While this bike’s frame is made from duralumin, a form of aluminum alloy which needs no paint because it cannot rust, the bike’s fork was steel.  When I purchased the bike, I knew it had a number of issues, the horrifically painted steel fork being one of them.

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As you can see from the photos, the spray paint appeared to be hiding rusting and pitting on the fork blades.  While I normally send all paint jobs out to the professionals, feeling that frame painters deserve their due, I decided that I wanted to prep this fork for painting myself so that I could assess the usability of the fork.

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Before venturing out into this unknown territory I did some research to determine what materials and tools I would need for the job.  I ordered emery cloth and wet-dry sandpaper in varying grades, some brass brushes (which will not scratch steel), and a few other items such as tack clothes and dish scrubbers.  All based on advice from Randy at mytenspeeds.com who has done some very nice paint work on his collection of bicycles. I knew that I did not want to use harsh, environmentally unfriendly chemicals for this job.

I fired up my new (non-wimpy) Dremel to use for the hard to access areas near the fork crown, but for the fork blades themselves I wanted to do all the work by hand, the old fashioned way. Unfortunately, whoever painted the fork did so while it was covered with rust.  When I began to remove the paint, I was disappointed to see just how bad the fork blades looked.

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The blades are pitted near the fork crown.  I wondered whether I should try to remove enough material to eliminate this pitting, worrying that I might take too much off and weaken the fork blades.  Then I remembered that fork blades are very thick and sturdy, given the job they must do, so I decided to keep going after observing the very nice brazing done on the dropouts and fork crown.  The fork is well constructed, and deserved my efforts, I felt.

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Cleanly brazed dropouts

While I was working, I was reminded of the bicycle frame that I built, and the effort required to sand the frame and remove excess brazing material.  This is a very similar process.  Using vigorous and speedy strokes with the emery cloth and sandpaper was the key to bringing the fork back to life.  Wearing a mask is a good idea, since you will be creating a lot of dust in the process.

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You can see the progression in these photos.  This process took about 4 hours, and yet  I still need to continue sanding with finer grade sandpaper to complete the work and have the frame ready for paint.  One thing to know:  it is most efficient to sand very quickly, mimicking the action of a power tool.  While my hands are now sore, I am happy with the results, and look forward to the finish work needed before I send this fork off to be painted.