Author Topic: Removing yellow cad off of bolts?  (Read 4111 times)

shelbydoug

  • SAAC Member
  • Hero Member
  • *
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #15 on: February 26, 2021, 07:10:34 AM »
Have used vinegar to remove the dichromate in the past. If full strength have to watch it as it can go too far and start removing the base zinc coat if you leave to too long

With the Rustoleum, the yellow wipes off in about 20 seconds or so on a new bolt. It doesn't seem  to affect the silver zinc at all.

I washed them down with water and buffed them slightly on a wire wheel.
« Last Edit: February 26, 2021, 07:15:15 AM by shelbydoug »
68 GT350 Lives Matter!

J_Speegle

  • SAAC Member
  • Hero Member
  • *
  • Just here to help :)
    • View Profile
    • ConcoursMustang.com
Re: Removing yellow cad off of bolts?
« Reply #16 on: February 26, 2021, 01:35:42 PM »
........I washed them down with water and buffed them slightly on a wire wheel.

Why would you want the final look to be brighter or shinier? Just asking :)

Would be concerned about removing the zinc with the wire wheel. But maybe it works for what ever your doing. Fir many applications/hardware I'm having to dull down the finish because it is too bright or shinny due to the way the zinc is down currently around here

Can understand having smooth shiny finish on some nuts but would get there by prepping the metal first and not having them dichromated when plated zinc.
Jeff Speegle- Mustang & Shelby detail collector, ConcoursMustang.com mentor :) and Judge

shelbydoug

  • SAAC Member
  • Hero Member
  • *
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #17 on: February 26, 2021, 03:36:20 PM »
........I washed them down with water and buffed them slightly on a wire wheel.

Why would you want the final look to be brighter or shinier? Just asking :)

Would be concerned about removing the zinc with the wire wheel. But maybe it works for what ever your doing. Fir many applications/hardware I'm having to dull down the finish because it is too bright or shinny due to the way the zinc is down currently around here

Can understand having smooth shiny finish on some nuts but would get there by prepping the metal first and not having them dichromated when plated zinc.

Shiny looks clean for now. It will oxidize naturally into that dull junk yard look soon enough. Plus you need to be sure that the chemicals are off of it so they don't eat through the zinc.

The luster on zinc parts naturally varies new. It can be very dull or almost chrome like.
It also depends on if they are dipped or E.G.
68 GT350 Lives Matter!

Drew Pojedinec

  • Sr. Member
  • ****
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #18 on: February 27, 2021, 09:26:34 AM »
Zinc survives 12 hours in a salt spray cell.
Yellow chromated zinc survives 250 hours.
Clear chromate survives 175.

Zinc plate, yellow chromate, use a sodium carbonate leach back for clear look. 250hours.
Or just dip a bolt in acid and lose 95% of it’s protective coating.

Sfm6sxxx

  • SAAC Member
  • Full Member
  • *
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #19 on: February 27, 2021, 11:43:37 AM »
Just did this on some bolts. Was too cheap to buy anything new (didn't have any evaporust handy) so raided the household cleaning shelf, found some toilet bowl cleaner called "Kaboom" used to remove scale & rust stains. It contains hydrochloric acid, made quick and easy work of the yellow zinc.

Kaboom-another product you can thank Billy Mays (rip) for pitching

6S1114

Cyclone

  • Newbie
  • *
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #20 on: March 03, 2021, 10:35:53 PM »
I have been using this product to remove cad and zinc plating from hardware that I want parkerized.
https://dwdavies.com/product/lime-x
You could use the product found at most hardware or grocery stores also called Lime-Away.
Soak the parts and rinse with clear water.

shelbymann1970

  • SAAC Member
  • Hero Member
  • *
    • View Profile
Re: Removing yellow cad off of bolts?
« Reply #21 on: March 10, 2021, 06:35:24 AM »
Can you elaborate your process and the solution you are using? Thanks. Gary

The re-dipping?  I have the gold dichromate stuff, I think Caswell sells it.  Mix it with water per spec ratio and just dunk the parts for 30-60s.  Use a heat gun to dry as they come out.

This won't work very well on bare metal parts.  A shiny silver zinc base is required to get the best results.
Thanks, Charles. Gary
Shelby owner since 1984
SAAC member since 1990
1970 GT350 4 speed(owned since 1985).
  MCA gold 2003(not anymore)
1969 Mach1 428SCJ 4 speed R-code (owned since 2013)