The Marston Sunbeam Club & Register Forum

General Category => Technical Discussion Forum => Topic started by: Thomas on January 28, 2021, 08:11:20 PM

Title: Cylinder studs
Post by: Thomas on January 28, 2021, 08:11:20 PM
Hi all,

before assempling the cylinder I wondered if I can make the studs good looking again. That works well for three of them. The front right one was rusty, though, and I applied Kurust. I can not bring it then to a status like the other studs even with chrome polish. It is certainly no chrome but what material is it? How should I proceed? 

Cheers, Thomas
Title: Re: Cylinder studs
Post by: singleminded on January 29, 2021, 07:15:17 AM
The most common finish for bare steel on motorcycles is Cadmium plating.
Unfortunately it is now a finish that you cannot get done unless you are in the Aerospace industry as it is generally banned, at least in Europe.
You could get them dull Nickel plated or Zinc plated..I replaced mine with stainless steel bolts.
  John
Title: Re: Cylinder studs
Post by: Thomas on January 29, 2021, 10:31:55 AM
Thank you, John! Cadmium plated... interesting. Never heard that before.Stainless steel is a good idea. I want to keep my studs because they are basically fine. Found this: https://www.vhtpaint.com/high-heat/vht-flameproof-coating Maybe also possible.
Cheers, Thomas
Title: Re: Cylinder studs
Post by: singleminded on January 29, 2021, 01:59:15 PM
Zinc plating would look fairly good as well.
Title: Re: Cylinder studs
Post by: Thomas on January 29, 2021, 02:08:32 PM
Ok, but I need a galvaniser for that. I think, given the potential amount of work and the minor stains, I'll leave it as is. Thanks a lot!
Title: Re: Cylinder studs
Post by: kbryt on January 30, 2021, 11:50:21 AM
Standard finish for 1930s nuts bolts etc seemed to be Parkerising, giving a black finish.
I believe cadmium plate was more 1940s on?

I have seen kits for parkerising on a small scale somewhere, can't remeber where.
Title: Re: Cylinder studs
Post by: klaudius on January 30, 2021, 12:04:46 PM
Hello
I am an electroplating professional. This is chrome.
Greeting
Claudius
Title: Re: Cylinder studs
Post by: Thomas on January 30, 2021, 03:58:03 PM
Chrome! I am no expert at all and though, Chrome is mirror glossy. How did they make it matte?
Title: Re: Cylinder studs
Post by: kbryt on January 30, 2021, 05:48:12 PM
There is a process known as satin chrome, very attractive, Norton used it a lot, it seems to be extinct here in UK.
Title: Re: Cylinder studs
Post by: klaudius on January 30, 2021, 07:52:22 PM
Hello
Chrome gets its shine from previously applied nickel. The bolts are chrome-plated directly. Here in Germany one speaks of hard chrome. I don't know the English term for it. Sunbeam also installed engine bolts in the nickel in parallel. Were there different suppliers?
Greeting
Claudius
Title: Re: Cylinder studs
Post by: kbryt on January 30, 2021, 08:14:04 PM
satin chrome is a matt finish, what it is applied over I do not know; I have had this same discussion on bike forums many times; it is not dull chrome, it is not standard chrome plate.
I have a feeling it was more aviation use.

look at an original Norton stud , nut or bolt, you'll see difference right away.
Its is a sort of pale grey finish, semi shiney.
Hard chrome here is different from chrome used for small parts;hard chrome for bearing surfaces such as fork tubes.
I doubt Sunbeam used an outside supplier for nickel or chrome plate.
Most big makes had there own plating plants.
Title: Re: Cylinder studs
Post by: klaudius on January 31, 2021, 01:14:24 PM
This is chrome. Applied very thinly and quickly. That is a typical picture. Only used for protection against corrosion. Here 3 bolts that are all proven to be built in 1932. Greetings Claudius.
Title: Re: Cylinder studs
Post by: kbryt on January 31, 2021, 01:20:32 PM
sod this , its getting tedious, I know the difference between chrome, satin chrome, nickle, dull nickle, parkerising, cadmium and zinc plate.
Title: Re: Cylinder studs
Post by: Thomas on January 31, 2021, 09:14:36 PM
Not so fast! For me as a non expert this is highly interesting and helps a lot.

Cheers, Thomas
Title: Re: Cylinder studs
Post by: Thomas on February 06, 2021, 04:52:09 PM
I have now contacted several galvanizers. All want about 250 quid for a single bolt because they first have to grind and prepare the surface. I have now simply painted the bolt with caliper paint in matte silver. Ten times cheaper and also does not look bad.
Title: Re: Cylinder studs
Post by: kbryt on February 07, 2021, 05:53:02 PM
grinding the surface??????????? :o :o :o :o :o :o :o :o
to replate something that is previously been plated the plating process is reversed to remove the previous plate.

Give those peopl ea VERY wide berth and find a proper ELECTRO PLATER, not a galvaniser.
Title: Re: Cylinder studs
Post by: Thomas on February 07, 2021, 07:37:30 PM
Look, I am no expert. Maybe I misunderstood the three independent experts. But according to Wikipedia a galvanizer and an electro plater are the same. So, don't worry, I painted the stud and that's it.
Title: Re: Cylinder studs
Post by: kbryt on February 07, 2021, 07:42:40 PM
in essence yes, in that they deposit metal onto metal by electrolysis. But thats wiki for you, worldwide source of misinformation.

Galavanised zinc has no place on a motorcycle of any era, water tanks yes.

painting the studs probably the best option unless you are a 100% fanatic.

I learnt a long long time ago to distrust "experts" preferring to consult the man who can actually do the job.


Title: Re: Cylinder studs
Post by: Thomas on February 08, 2021, 09:01:40 AM
Well, I am more with Claudius, who obviously is an expert (we are all experts in our fields, aren't we). Zinc plating came up here but was waived after Claudius' definite information. As a layman I carefully listen to experts (who are normally able to do the job by definition) and have no reason for distrust. But I agree, Wikipedia (worldwide source of misinformation? Well...!) should only be the first rough source. Then I go to experts like we have in this forum.  :D
Title: Re: Cylinder studs
Post by: Russ on November 24, 2022, 09:51:42 AM
nothing to do with chroming.....but if you want to make your nuts and bolts black (Blued) there is a fairly simple solution......heat the object evenly till Blue / purple colour and then immediately immerse into oil and agitate you can do this process several times depending on how black (Blued) you want them......by the way I use old engine oil....LOL.....results were pretty good.....of course you can buy cold blueing chemical treatment which is easy see below