| [ Total Views: 855 | Total Replies: 9 | Thread Id: 105115 ] |
|
|
 gt_51
Learner Dubber
Posts: 6
Threads: 3
Registered: November 11th, 2011
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on February 17th, 2014 at 06:36 PM |
|
|
welding in rust
I read the information in Tech Talk comparing Por-15 Rust Bullet and Epoxy mastic 121. I have been using Por-15 so I bought a litre of Rust Bullet and
2.5 litres of Epoxy mastic 121, to try. If someone can help, my question is when I remove rust e.g. at the bottom of the engine lid where they all
rust, I have drilled the spot welds out to remove the inner panel, cut the rust out, went through the Rust Bullet process now what happens when I weld
the panel back in? All the rust prevention will be burnt off. How do you prevent this?
|
|
|
68BUS
Wolfsburg Wizard
Posts: 485
Threads: 19
Registered: July 1st, 2011
Member Is Offline
Location: Brisbane
Theme: UltimaBB Pro Blue
Mood: Berwildered
|
| posted on February 17th, 2014 at 06:42 PM |
|
|
Rust bullet does not take weld too good. Buff back just what you need to then coat with weld through primer (copper rich).
Then get what you after with rust bullet. Follow it with penatrol to vet the last of it.
1966 Aussie 11 Window
|
|
|
 helbus
A.k.a.: Pete S
Super Administrator
Mad fabricator, paint and body
Posts: 7386
Threads: 312
Registered: September 1st, 2002
Member Is Offline
Location: In the garage chopping cars into bits
Theme: UltimaBB Pro Blue
Mood: In the thinking chair
|
| posted on February 17th, 2014 at 06:49 PM |
|
|
There are numerous 'weld through primers' The Copper primers spatter less when MIG welded. Any Automotive paint supply place will have it. Dont use
Cold Galvanising Primer. It will spatter huge and blow out the weld.
|
|
|
psimitar
Son of Jim - Creator of Good
Posts: 2506
Threads: 148
Registered: January 1st, 2009
Member Is Offline
Location: North East Melbourne, VIC
Theme: UltimaBB Psyche Blue
|
| posted on February 17th, 2014 at 08:01 PM |
|
|
I've used galvanised primer without any spatter issue for plug welds. Some say a slightly higher setting helps get thru the primer but if it's good
quality, like Wurth, then should be fine.
Once welded n cleaned up I thin the rust paint of choice so that it can flow into the join between the sheets of metal. Then for overkill some
rustbuster wax or Waxoyl, cos it's got inhibitors in it, or Bilt and Hamber ( tho the Oz importer WAY over charges for it but your choice )
madness is in the eye of the beholder  |
|
|
gt_51
Learner Dubber
Posts: 6
Threads: 3
Registered: November 11th, 2011
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on February 17th, 2014 at 08:42 PM |
|
|
Thank you for your help. I can see the point behind putting wax etc. on after welding. However wouldn't the weld through primer burn off as well and
welds rust so quickly. what do they do in the factory?
|
|
|
modnrod
Fahrvergnugen
Posts: 978
Threads: 50
Registered: March 17th, 2011
Member Is Offline
Location: Midwest, Westoz.
Theme: UltimaBB Pro Blue
Mood: Old School Volksies!
|
| posted on February 17th, 2014 at 09:59 PM |
|
|
| Quote: | Originally
posted by gt_51 what do they do in the factory?
|
They dip it.
|
|
|
helbus
A.k.a.: Pete S
Super Administrator
Mad fabricator, paint and body
Posts: 7386
Threads: 312
Registered: September 1st, 2002
Member Is Offline
Location: In the garage chopping cars into bits
Theme: UltimaBB Pro Blue
Mood: In the thinking chair
|
| posted on February 17th, 2014 at 10:24 PM |
|
|
The factory spot welds the panels with robots now. Then does an electrocoat dip.. The Copper weld primer is the best chance you have.
Steel is iron. If it is iron I assure it will rust. Cannot stop it.
|
|
|
gt_51
Learner Dubber
Posts: 6
Threads: 3
Registered: November 11th, 2011
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on February 17th, 2014 at 11:12 PM |
|
|
Thank you for all that info, I will get some copper weld primer, then after I have welded the inner panel I will try and get some more Rust Bullet in
there.
|
|
|
68BUS
Wolfsburg Wizard
Posts: 485
Threads: 19
Registered: July 1st, 2011
Member Is Offline
Location: Brisbane
Theme: UltimaBB Pro Blue
Mood: Berwildered
|
| posted on February 18th, 2014 at 08:12 AM |
|
|
The one that I have had success with is U-Pol Weld Thru No2
It is in a silver tall can with green writing from memory. U Pol as a 1-4 numbered range with each number a different thing.
1966 Aussie 11 Window
|
|
|
psimitar
Son of Jim - Creator of Good
Posts: 2506
Threads: 148
Registered: January 1st, 2009
Member Is Offline
Location: North East Melbourne, VIC
Theme: UltimaBB Psyche Blue
|
| posted on February 18th, 2014 at 07:27 PM |
|
|
| Quote: | Originally
posted by 68BUS
The one that I have had success with is U-Pol Weld Thru No2
It is in a silver tall can with green writing from memory. U Pol as a 1-4 numbered range with each number a different thing.
|
Yup, this stuff is good too. I thunk #2 is zinc and #3 is copper. Can't quite remember.
as for burning off. Yes it does on the weld and a bit around it but the rest is fine and hence gives protection. As I said, thinned down rust
inhibiting paint will fill the gap between the panels and so any moisture caught near the weld will take a bloody long time to rust out. if you use a
moisture curing paint, like KBS, then I believe that won't be an issue.
madness is in the eye of the beholder |
|
|
