Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
The authoritative public forum
for Metal Finishing since 1989
-----
Need harder deposits in Nickel Sulfamate Electroforming
adv.
Q. I have some problem in electroforming process. When I start the plating on a acrylic or a.b.s plastic mandrel after some hours the deposited layer burst from anywhere. In my sense the solution is going impurities and deposit is harder. Please tell me about my problem.
Ashfaq- Pakistan
A. Hi, Ashfaq.
You presumably have internal stresses (most plating is tensilely stressed). Perhaps you could start with "stress tabs" and Hull cells to acquire some knowledge of the characteristics of the deposit?
You did not yet mention what it is that you are trying to electroform, nor what metal you are using to make the electroform, so please get back to us.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
A. Check stress. Control stress. There are many factors which are important for stress. What type of bath are you using?
Payal Mag- Charlotte, North Carolina
Q. Hello,
I have some problems in nickel sulphamate bath, first of all hardness of deposition and secondly low rate of deposit . In my thinking my first problem related to impurities like copper and carbon etc. Kindly guide me the proper way to clean the solution. I want to prepare another bath, kindly tell me about this in detail, that what is the right composition of solution and the current densities in initial stage and later and please tell me about pre plating treatments especially A.B.S and acrylic plastic for electroforming.
Ashfaq [returning]- Pakistan
A. Hi,
High hardness and slow deposition. You probably are plating below normal current for that bath. Also, to clean solution two things:
1- Dummy with large cathode stainless steel corrugated sheet at very low current overnight,
2- Heat bath to normal, add activated carbon, let adsorb 4 or 6 hours organic contaminants and filter out.
Do you have a supplier for your chemicals? You should consult him and contact Nickel Development Institute in Toronto, Canada for details on preparing mandrels.
Guillermo MarrufoMonterrey, NL, Mexico
adv.
"The Sulfamate Nickel How-To Guide"
by David Crotty, PhD
& Robert Probert
published Oct. 2018
$89 plus shipping
Q, A, or Comment on THIS thread -or- Start a NEW Thread