Nickel plating

[Master]

Tried my hand at nickel plating. May have left item in solution too long. It turned black. The black does polish off, but the result is an odd silver/yellow color.

 

[roughcaster]

hi i think your power source could be to high this is the usual cause, gary

 

[Master]

I used a 1.5 volt AA battery hoping to keep power down. I wonder if leaving it in the solution too long is the problem.

 

[cl350rr]

Current may be more important than voltage, try a small wall wart power supply or some resistance to control the lower the current

 

[SmithDoor]

This may help few
https://www.instructables.com/id/High-Quality-and-safe-Nickel-Plating/
Dave

 

[a41capt]

The black smut may be from an impure nickel source. What are you using for the cathode?

 

[Master]

I used 99 % pure nickel for both anode and cathode to make the solution. Then used the same anode for the plating. It plated, but wasn't a pleasing color. The engine is the Edwards Radial 5. It came out so nice that I want the plumbing to look the same. I may just end up painting the exhaust and intake pipes black. The brass shines up well, but I know it will tarnish in time.

 

[doc1955]

I used 99 % pure nickel for both anode and cathode to make the solution. Then used the same anode for the plating. It plated, but wasn't a pleasing color. The engine is the Edwards Radial 5. It came out so nice that I want the plumbing to look the same. I may just end up painting the exhaust and intake pipes black. The brass shines up well, but I know it will tarnish in time.

I did my brass zoomyie tubes that I have for my Little Demon engines and they came out really nice. The most important thing is make sure they are really clean. I put mine in the solution that I made and it only took a minute or so. I did do videos showing it stop by and take a look.

 

[a41capt]

I used 99 % pure nickel for both anode and cathode to make the solution. Then used the same anode for the plating. It plated, but wasn't a pleasing color. The engine is the Edwards Radial 5. It came out so nice that I want the plumbing to look the same. I may just end up painting the exhaust and intake pipes black. The brass shines up well, but I know it will tarnish in time.

Another thought, if you’re set on a really nice nickel finish is a brush plating system from Caswell. I’ve used one of their gold plating brush kits for small firearm parts (triggers, screws, etc.) and the results were great. Comes with a wall wart, wand, bandages, and solution. Truly plug and play.

John W

 

[Peter Twissell]

Have you considered electroless plating? I bought a kit from Caswell several years ago and used it for motorcycle parts, with good results.
Unlike electroplating, electroless plating does not build up on edges and effectively plates into crevices, inside bores etc.

 

[bobvines]

It's been a while, but I used to support the plating shops at work (before retirement), but was not a Chemical Engineer. To get good plating, nickel included, you need the proper current per unit of surface area -- not too high or too low. I remember that our nickel anodes were kept inside cotton socks made for a close fit on them. I don't recall whether that was simply to prevent anode particles from falling off & contaminating the bath/part or if it had anything to do with eliminating the blackening.

 

[Master]

Thank you all for the inputs. I've decided to just leave the intake plumbing polished brass. Oddly the intake pipes have been the most challenging in this entire project. After 8 months on the radial, I'm ready for the next challenge. Thanks again.

 

[mayhugh1]

If you haven't already seen this, take a look at post #290. There might be an answer there:

https://www.homemodelenginemachinist.com/threads/270-offy.31486/page-15
Terry

 

[SmithDoor]

I did nickel plating when was 10 it was simple. It came package of chemical a nickel wire with battery w/coper wire.
The instructions said do not put copper in the electrolyte that was connected to nickel wire or plating will be dark.

I put some documents collect on plating in downloads later.

Dave

PS:
If looking for simple and safe ways to plate look for kids projects.

The easy safe two plates metals nickel and copper on to steel.
Zinc is next on list for Plating

 

[terryd]

I did my brass zoomyie tubes that I have for my Little Demon engines and they came out really nice. The most important thing is make sure they are really clean. I put mine in the solution that I made and it only took a minute or so. I did do videos showing it stop by and take a look.

Hi,

Searched your channel but couldn't find your plating video and don't have time to watch a whole series so a link would be welcome.

Regards

TerryD

 

[doc1955]

Here is the first of 2 videos. If you do a search in youtube of nickelplate doc0455 it should have come up.

nickelplate

 

[SmithDoor]

I uploaded my files to the Downloads
https://www.homemodelenginemachinist.com/threads/electroplating-copper-nickel-zinc.32304/
Dave

 

[tim9lives]

There’s a few YouTube videos of Nickel Plating which oversimplified the process. I must have read articles for a full 3 weeks because I had the same problem you described. The coating turned black.
Finally after a decent bit of investigation I came to the conclusion that the Watts Nickel Solution is what works. I plated a few parallels which I used in my mill vise. Mind you,My main motivation for the nickel plating was and is to prevent rust on some of my workshop tools. I must admit, I’m not a model builder.
Long story short... The Watts Nickel Process has held up remarkably well. I did this nickel plating about 3 months ago and use these parallels daily. They are just cheap shop parallels I made out of cold rolled steel bar.
Give me a day or so, and I’ll look for my notes and post those plus I’ll post a couple of pictures of the parallels.
All of that said, nickel plating isn’t hard but there are some rules which must be followed in my opinion. Break those rules and you do get that black smut.
On a side note....Zinc Plating is a whole lot easier.
******
Here’s one of my notes I copied from a forum. Also, you should use distilled water.



I would suggest a bath comprising 300 g/l nickel sulphate, 30 g/l nickel chloride, 40 g/l boric acid. Operate at pH = 3.8-4.2 at about 50 °C. Cathodic current density about 40 ASF, anodic cd about 50 ASF. This is known as a Watts nickel bath.

Add about 0.5 g/l sodium saccharin to harden and brighten it. If you want to be really clever, add about 10 g/l c

Cobalt sulphate and this will also brighten and harden it.

by the way....the nickel plating will mimic the surface it’s plating. So if the surface isn’t polished shiny before you start....it’s not going to be shiny after plating. And the below attachment of my parallels shows just that. I didn’t shine or polish those parallels before plating. I did do an alkaline dip before plating and that’s a whole additional process. Plus...wear gloves. And you must get that water break on the part when you spray them with distilled water to test if the part is totally clean.

*

 

[tim9lives]

https://www.nickelinstitute.org/media/2323/nph_141015.pdfFrom page 13 and 14 of above PDF........

CHEMISTRY OF NICKEL ELECTROPLATING SOLUTIONS
The Watts Nickel Plating Solution
The majority of nickel plating solutions, particularly those used for decorative plating, are based on the ‘Watts’ formulation developed by Professor Oliver P. Watts in 1916. The Watts electrolyte combines nickel sulphate, nickel chloride and boric acid. While the proportions may vary according to the application, a typical formulation together with operating parameters is given in Table 2.
Table 2
Typical formula and operating conditions for Watts nickel electroplating solutions
Function of Ingredients
Nickel Sulphate (NiSO4.6 H2O) Nickel Chloride (NiCl2.6 H2O) Boric Acid (H3BO3) Temperature
pH
Cathode Current Density
Deposition Rate
240-300gL-1
30-90g L-1
30-45g L-1
40-60°C
3.5 - 4.5
2-7A dm-2
25-85μm h-1
The nickel sulphate is the primary source of nickel ions (Ni++) with nickel chloride a contributing source. Nickel chloride has two major functions – it appreciably increases solution conductivity thereby reducing voltage requirements and it is important in obtaining satisfactory dissolution of nickel anodes.
Boric acid is a buffer and has the major function of controlling the pH of the solution. As discussed in the previous section, due to the cathode efficiency being less than 100% there is a tendency for the pH to increase as some hydrogen ions (H+) are discharged to liberate hydrogen gas. Regular additions of sulphuric acid are therefore required to adjust the pH. Boric acid limits the effect on the pH resulting from the discharge of hydrogen ions, thereby, simplifying pH control. The mechanism by which boric acid operates is complex, but it is generally understood that it exists in solution as a mixture of borate ions and non-ionised boric acid. When hydrogen is discharged some boric acid will ionise to replace the hydrogen
ions lost and so the pH change is limited. At the same time, borate ions form. When acid is added to adjust the pH, these borate ions combine with hydrogen ions to reform boric acid. Boric acid is therefore only lost through dragout or other solution losses.
The Role of Addition Agents
Watts nickel plating solutions are commonly used for functional applications as will be discussed in a later section. Deposits from Watts solutions without additives are soft and ductile but dull in appearance. The appearance and properties can however be dramatically changed by the use of addition agents. The addition agents consist of organic and certain metallic compounds selected to brighten and level the deposits. As will be discussed further in the section on decorative plating, addition agents may be used to produce semi-bright, bright or satin nickel coatings.
Bright Nickel Plating
In bright nickel plating, four main classes of addition agents are used:
‘Carriers’
(Confusingly these are sometimes also referred to as Brighteners of the First Class, Secondary Brighteners or Control Agents)
These are usually aromatic organic compounds containing sulphur. Examples are benzene sulphonic acid, 1,3,6-naphthalene sulphonic acid (sodium salt), p-toluene sulphonamide, saccharin and allyl sulphonic acid. The major function of carriers is to refine the grain structure and to provide some increased lustre compared with additive-free solutions. Many carriers, for example saccharin, also have significant stress reducing properties. Carriers introduce sulphur into the deposit and the effect of this incorporated sulphur is discussed under decorative plating. Consumption of carriers is largely by dragout as they are not consumed rapidly by electrolysis.
‘Brighteners’
(Also referred to as Brighteners of the Second Class, Primary Brighteners, Levelling Agents)
In combination with carriers, brighteners produce brilliant deposits with good ductility and levelling properties over a broad current density range. There are a wide range of brighteners used (generally supplied as proprietary mixtures). Compounds include formaldehyde chloral hydrate, o-sulpho benzaldehyde, allyl sulphonic acid, 2-butyne-1, 4-diol, thiourea, coumarin and many others. Brighteners are generally present in very low concentrations and are consumed by electrolysis. They therefore need to be replenished on a regular basis in order to maintain the desired brightness.

 

[Master]

Thanks for all the inputs on nickel plating. I gave up and went with the brass. This is the Edwards Radial 5. Plumbing bending was a new experience.