
plating, anodizing, & finishing Q&As since 1989
Problems & solutions for barrel plating danglers and alternatives
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Current question and answers:
December 22, 2020Q. Hello,
I'm struggling with plating (zinc) off long workpieces (nail-screw-spike) 30-35-40 Cm /11-13-15 inches)
Due to production volume process have to be carried in barrel system. I want to avoid bending of product and entanglement.
That's why I'm looking for solution related to construction of plating barrel.
I'll appreciate your help and tips .
- Bydgoszcz Kujawsko pomorskie, Poland
December 2020
A. Hi Åukasz,
I think regular dangler contacts would be best, but that the barrels should be 11" internal diameter or less so there is no way the spikes can get vertical but must essentially remain horizontal.
Luck & Regards,

Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
↓ Closely related postings, oldest first ↓
2002
Q. I have a problem Zinc plating a hook on a barrel line. My barrels are 36" x 24" and are rated at 500 Lbs. capacity, but these hooks catch against each other, against the dangler, and bend each other out of shape. I've had to reduce the rpm's to 2 rpm and I am only able to load the barrels to about 80 lbs.
What should I be plating these hooks in? Vibratory barrels? Please help.
Thanks again,
Rodrigo Salinas- El Paso, Texas
2002
A. Most "vibratory" barrels are employed on electronic parts 25 times smaller than yours.
Parts tangling together is a perennial problem in barrel plating and there are only partial solutions, which include: different contact styles (cones, bars, external buttons, etc.) in lieu of danglers, small loads (like you are running), and periodic reversing starters so the barrels only rotate a few seconds in each direction.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002
A. Vibratory barrels may be a good option, but they are expensive. May I suggest trying a barrel with button danglers, and also using conductive plating media or some other zinc plated parts that can be mixed with the hooks and separated later.
Karl Weyermann- Lebanon, Kentucky, USA
2002
Q. OK, vibratory barrels are too expensive & too small, so let's talk about button contact barrels, cone contact, or other forms of dangler-less system. Does anybody have a good diagram on how to retrofit a regular barrel?
Rodrigo Salinas [returning]- El Paso, Texas, USA
2002
A. The reason a dangler snarls up when plating nesting parts is that the dangler does not rotate with the barrel and the mass of parts; it must keep snaking its way through the mass. So, the hope is that a style of contact that rotates with the barrel--so there is nothing stationary in the revolving barrel--will minimize the snarling.
So, what you are trying to do is get the electricity to the parts without leaving anything stationary like a dangler inside the barrel or mass of parts. The buttons, or contact bars, or cones, or whatever, are fixed to the cylinder and rotate with it and the parts.
It is difficult to do yourself because this requires some kind of informal "electrical brushes" arrangement whereby the contact surfaces (fixed inside the barrel) get their current from a contact on the hanger arm. All plating barrel manufacturers are able to supply such contact arrangements for dangler-free contacts though. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002
A. Hi Rodrigo Salinas,
If you're looking for a long term solution for plating these hooks I would suggest you to go for rack plating. I guess you can expect uniform deposition and faster plating rate. It's possible to rack and unrack these hooks quickly.
Venkat Raja- Kitchener, Ontario, Canada
Passivating steel dangler knobs
2003Q. We do barrel-electroplating (Nickel, Copper, etc.) We use steel danglers in barrels (not St. Steel) From time to time we remove plated deposit from danglers to reuse dangler again. We remove coating by hammering them.
Questions:
1) Is there a way to passivate the steel dangler so that removing the deposit becomes very easy?
2) Is there an easy way to remove the deposit instead of hammering the danglers?
Thanks a lot for replying to these questions
Pravin AagashePlating Supervisor - Bombay, Maharashtra State, India
2003
A. Hi Pravin. You could try electropolished stainless steel dangler knobs. Electropolished parts have very little "tooth" and are quite passive, so it's generally easier to remove deposits from them. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Why not Titanium danglers?
2007Q. Hi
Why is titanium never used as a dangler in barrel plating of decorative finishes?
Obviously it is more expensive than copper or brass from the outset, but the copper & brass danglers need constant cleaning & attention to remove the plating that accumulates on them. Would it not be less work using titanium danglers?
buyer - Durban, KwaZulu-Natal, South Africa
2007
A. Titanium is a terrible conductor of current, so it would not work as a dangler.

Jon Barrows, MSF, EHSSC
GOAD Company

Independence, Missouri

2007
Q. Hi Jon
thanks for your reply.titanium of course works as a conductor when used as an anode basket for nickel chips.
Surely, then., it would be acceptable as a dangler?
- Durban, KwaZulu-Natal, South Africa
2007
A. Natasha,
As Jon mentioned Ti is not used for danglers because of lower conductivity and higher contact resistance. Copper is the 2nd best conductor, I think brass is the 6th best, at room temp of course. As you said Ti is more expensive. Based on these two facts alone, what kind of contacts would you put on danglers? Ti is used for hooks and baskets mainly for its strength, heat and corrosion resistance, it is compatible in certain plating solutions.
process Engineer - Syracuse, New York
A. Hi. There's a bit of a semantics issue here. The dangler as a whole is a heavy copper cable with heavy plastic insulation and a bare contact knob on the end. I'm sure Natasha is speaking only of making the knob out of titanium, not the whole cable.
I could be wrong but I think the actual problem is not conductivity or wear, but polarity. My belief based on practical experience is that titanium is not actually resistant to the acids used in plating: rather, the titanium oxide coating it develops from being anodic is what is acid resistant. Dangler knobs are cathodic and I think they will quickly dissolve in the plating baths.
Luck & Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Are Copper Danglers F006 Hazardous Waste?
2006Q. Why are used danglers classified as F006 waste? With copper over $3.00 a pound why can't they be sent to a recycler instead of my company having to pay to get them hauled off as F006. We send them off 300 pounds at a time. Thanks
Mike CappsLab Tech - Bon Aqua, Tennessee, USA
2006
A. Who says they are, Mike?
I'm not sure that you are interpreting the regulation correctly. I'd need to restudy it myself, but I don't understand why you can't strip the rubber off, triple rinse it and dispose that part as simple waste while selling the copper as scrap. What is the reasoning you are using, or others are giving you, that causes you to equate a dangler with a waste sludge? The parts that you are plating are clearly not hazardous waste; why should the danglers you are plating be?
In the case of a disputed interpretation, common sense should prevail; and it tells me it is an environmental travesty to landfill electrolytically pure copper metal. At the least, any person who so orders should sign their name on said orders.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Barrel leads (danglers) break when plating long fasteners
May 22, 2011Q. Dear sir,
When we plate long length fastener items like length M10x210 mm or M10x238 mm, barrel leads break during process and we have to face loss of time, and cost.
Is there any way to stop such type of problem?
Help me!

Kapil Gupta
tools - Faridabad, India
May 25, 2011
A. Dear Gupta,
Use a tight PVC sleeve over the solder Joining point (Dangler and the cable).
All the best.
- Bangalore, Karnataka, India
March 11, 2013
Q. We now use a Solder Stripper to periodically (every four hours!) clean the Tin off the cathode buttons in my plating barrels. This chemical is my highest quantity of hazardous waste generated and I have made it one of my goals to reduce or eliminate. Any suggestions along those lines would be helpful. The chemical is Ammonium Bifluoride and Hydrogen Peroxide, so it is a safety concern as well as a hazardous waste.
My idea is to periodically take out the anode basket, but in a blank panel and then reverse the current to plate off of the buttons (as anodes). Is this feasible? Can it be done? I worry about plating off the Chrome or Iron when they are clear of Tin. I could make the buttons out of Platinized Titanium or Zirconium if that was a concern, but I feel that could become a wearing issue as well.
Thanks for any thoughts on this.
Mike
Department Engineer - Lake Mills, Wisconsin, USA
A. Hi Mike. Just brainstorming here, but I am not yet convinced that plain button contacts wouldn't work. They could be made of electropolished 316 stainless steel, which is both very passive and very free of tooth; I think with luck the plating would fall off or almost fall off.
As for deplating, I don't think you will attack the substrate of the buttons if you keep the voltage low.
Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 13, 2013
Q. Thanks Ted,
Let me clarify. The cathode buttons are Stainless Steel. They are slightly attacked by the stripping solution now, so they do not stay smooth long, but become dull. Normally, they are bright (decorative) but they are not SS316 either, probably SS304. (We use platinized Titanium for anode parts.) The Tin plated onto the cathode buttons forms a granular surface, very tenacious and also plates out onto the PE barrel surface, all within about 4 hours of use. The total current is 23 Amps at about 7 Volts DC.
- Lake Mills, Wisconsin, USA
March 19, 2013
A. Why not use a nitric acid stripper formulation instead of ammonium bifluoride? It would not attack the stainless steel. Other than the fumes, it may have less concerns about human exposure.
Lyle Kirmanconsultant - Cleveland Heights, Ohio
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March 20, 2013 Q. The company had used a Nitric acid based stripper in the past. Fumes were an issue then. I agree that using an oxidizing acid would be the way to go. I will see if using a more dilute solution might still work without the brown fumes.:) - Lake Mills, Wisconsin, USA March 20, 2013 A. Another route, avoiding attack on the stainless steel, would be to dissolve the tin electrolytically in sodium hydroxide. ![]() Harry Parkes - Birmingham, UK |
Substitute for copper rod in plating barrel
October 15, 2020Q. Hello
I use barrels to coat mild steel (MS) spokes with zinc; I use acid zinc process. The copper rod used to provide current to MS spokes (cathode) catches a lot of zinc deposit. can I substitute copper with some other material, perhaps titanium?( I have tried copper wire but the wear and tear is fast)
- mzn India
October 2020
A. Hi Sam. Can you send a photo to mooney@finishing.com for posting here? I'm not sure what you mean by "the copper rod". Most plating barrels have danglers. But some plating barrels have, instead, a copper rod running from the center of one hub to the center of the other, from which you can dangle something to bring current to the parts. But making a suggestion how to improve what you have when I don't really know what you have is tough :-)
Luck & Regards,

Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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