Technical & Reference Section > Tech and Restoration
1982 Shimano 4000 build.
Avro:
I got the bars from someone on here a while ago, I do not remember who.
I have just looked at the bars sold be the seller you mention and I think you are right, they are one and the same.
factory pilot:
Really coming together :4_17_5:
bobafett:
Looking great mate :coolsmiley:
P J Tunni:
Loving this, absolutely stunning! :smitten: Agree on the tyres, i ride all my bikes so i always go for repops.
Avro:
The bank holiday weekend has given me time to make progress with the Shimano 4000. As I had two full days available I decided to tackle the cranks and chainwheel. This will mean trying out my new anodising tank. I have set up my anodising using fresh chemicals, new electrodes and new hardware.
The cranks are Shimano 600 Arabesque, from a road groupset really but perectly fine for BMX. They came to me with a 43T Shimano chainwheel and it will be retained. The original gold anodising is in a sorry state.
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The first job was to strip the anodising and deep clean the metal. The anodising is removed by dipping in a solution of caustic soda, this also cleans and draws impurities out from the surface. These impurities are further cleaned with a solution of nitric acid, these dips leave the metal super clean and raw. The caustic soda also etches the surface which will have to be remedied with polishing. Here are the cranks after dipping:
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Polishing next, I probably go over the top with this stage but never mind. I started with p240 on specific areas where burrs needed flatting or deep scraches needed to be removed or at least minimised. Then it was just a laborious case of flatting down through the grades, 800 > 1200 > 2000 > 2500 and finishing with Peek polish. This was all done by hand as I did not want to loose edges and stamps. The 'Shimano 600' logo was masked with tape until I got to p2500. I hate seeing those over-polished parts on ebay where all the detail is obliterated. Here is the drive-side crank after polishing, it will be gloves from now on:
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The parts are cleaned with soapy water, making sure no beading occurs, and rinsed in deionised water.
I have investing in a large assortment of aluminium nuts, bolts, washers, studs and heavy titanium wire. With this hardware I will be making custom jigs for everything I anodise. I have high hopes for the countersunk screws I have bought as they will give a very good electrical contact with minimal surface area.
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