netneut
finishing.com -- The Home Page of the Finishing Industry
A website for Serious Education, promoting Aloha,
& the most FUN smiley you can have in metal finishing


Finishing.com has been free for 22 years,
but without net neutrality we could soon
cease to exist. Do us a solid, click on
the banner, and contact congress today!
HomeFAQsBooksHelpWantedAdvertiseForum
topic 1258

tin plating bath with low throwing power


(1998)

Our acid tin bath has a very low throwing power, we have checked all conditions including rectifiers, and everything seems to be in parameters. The only other thing I can think of would be an organic contamination from the brightener decomposition. Is this possible? how can we check for this?

Your prompt advice is greatly appreciated.

Carmen Ma. Rosa
electroplating shop


(1997)

Without the highpriced toys to test this, I would run a hull cell on a new (lab) solution, one with your current solution and then carbon treat it much more than required, bring the three brighteners back up to required levels and run another hull cell on that. The carbon treat can be on a liter sample.

This will tell you a lot about your problem and organics.

James Watts
- Navarre, Florida


(1998)

Carmen,

Temperature can kill throw in Tin Methane sulfonate bath. Is this the bath you use? If you are rack/barral plating at 5-50 ASF, you must maintain temperature below 80'F or the reverse reaction becomes too strong in the low-throw regions. Additionally, these baths should be routinely Carbon filtered cold to remove your aforementioned organics. The problem is that some carbonaceous species appearing in this bath don't respond well to C treat, so after several C treatments, you will note the failure of the bath to respond to C treatment and you must dump the bath. A good way to manage this bath is to note the time/amp-hours to bath failure, divide by the number of gallons, then dump and replace equal percentages regularly. This way your bath will operate at steady-state over time.

Regards,

Dave Kinghorn
Dave Kinghorn
Chemical Engineer
SUNNYvale, California




This public forum has 60,000 threads. If you have a question in mind which seems off topic to this thread, you might prefer to Search the Site

ADD a Q or A to THIS thread START a NEW THREADView This Week's HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices


©1995-2017 finishing.com     -    Privacy Policy
How Google uses data when you visit this site.