Could you not replace them with BZP off the shelf?

Wolfe,

The old bolts can indeed be replated, but the cost for any trade plater to do so would be way above the price of new stuff off the shelf, stainless, BZP or otherwise.

I'm a retired industrial chemist with a background in electroplating, and wouldn't consider reprocessing a few old old bolts for a minute. The only exception would be parts that had special threads or shapes.

Eug

When I had to recover "milllions" of bolts and nut for a major project, a local plater did all the "barrel" loads I could provide at a fairly reasonable cost. Project was a full size mainline diesel electric locomotive.

If it was just nuts and bolts it would be straightforward enough, but when you get on to 5/16 CEI half domed head bolts , things are not so simple, buying new ones isn't really an option. Also there is the myriad number of little brackets and other associated parts that are manufacturer specific. If it was just bolts I would buy new, if I lived somewhere civilised enough to have a platers within a 150 mile round trip then I would have them all barrel rolled for a very reasonable price, but I don't.

After a plater lost a load of irreplacebale motorcycle parts I thought 'right I'm not doing that again' I bought a plating kit off Gateros, several years ago now. They have been more than helpful with telephone enquiries and free top ups over the years. They have now started a zinc/ nickel kit which sounds very attractive , I'm hoping they will upgrade me from my zinc kit. Whether Gateros will do that or not I have no hesitation in recommending them and their plating kits.

I do not know where you are located but Action Plating of Basildon will replate a large bucket of nuts, bolts and other small pieces (and not so small) for £20 (last year). I have used them for years with no complaints and zinc finish is provided in addition to passivating etc. Some parts are barrel plated and some are individually hung on copper wire into the plating vats. No connection other than as a satisfied user.

I always thoroughly clean up and/or refinish the parts before plating (including any threads). The plated finish very much depends on how good the parts are going into the plating process.

One thing to watch is the effect of plating on tightening torques. Zinc can act as a lubricant, while nickel is the opposite, so in effect a 'correct' torque for plain steel on a zinc bolt will overtighten, and on nickel will undertighten.

Zinc is a blue shade of silver, while nickel is on the yellow side. Mixing the finishes will really be obvious.

Cheers, Tim

nickel plating looks best on an old bike and if polished can look like chrome but everything has to be grease free,dont worry about embrittlement as you only do the heads on bolts. a kit will last you years if looked after.

nothing difficult about plating the heads only tim, simply hang them with a copper wire into the plating tank. very few bolts on a bike need need high torque eg mudguards,stays petrol and oil tanks

The idea that heads-only plating simply involves dipping the heads into the plating vat with no plating ever into the shoulder relies on two things I have never come across in such situations:

1. Accurate wiring which allows the bolt to hang exactly vertical

2. A plating vat which is never disturbed once the parts are delicately lowered in.

Embrittlement does not affect mild steel as much as high tensile stuff, but how is our man to know which of his (totally unmarked) bolts are mild steel? For sure the parts book will not say.

And yes, of course this post plating heat treatment was given to parts originally.

All this fuss because our man cannot bring himself to use stainless …

Cheers, Tim

"Stainless" is not always the answer. it does not suit some applications and not all "stainless " bolts purchased are what you expect to purchase. There is a lot of cr&p out there