All MetalShaping

Go Back   All MetalShaping > General Metal Shaping Discussion > Welding Sheet Metal
  Today's Posts Posts for Last 7 Days Posts for Last 14 Days  

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 10-22-2018, 10:54 AM
BTromblay BTromblay is offline
MetalShaper of the Month August 2018
 
Join Date: Oct 2015
Location: Mukwonago, Wi
Posts: 303
Default Aluminum welding flux clean up

Hi,

I was working on my Stinson L-5 over the weekend, it has been a long term restoration. The plane was build in 1942 for the war and was used as an observer. In 1948, it was transferred to the United States Coast Guard and was used to find illegal moonshine stills in the Appalachian mountains, this is how it will be restored.
a.jpg

I making the stainless steel firewall and aluminum air deflector. In the deflector, is a little aluminum funnel that is used to drain fuel overboard during your pre-flight inspection.
b.jpg

The question is gas welding flux clean up. It seems that all the books I read, reference using a stainless steel brush for clean up post weld. I have heard that you can use vinegar, or hot boiling water as well. For my application, I want to leave the weld, not grind it down. On the airplane parts, seldom do they grind the weld and seldom, if ever do you see heavy wire brush marks on the weld.
3.jpg
4.jpg

I love the quality of my part, even if looks like it was welded more on a Monday, verse Friday afternoon. But can you soak the part in water for an hour or more to dissolve the flux, instead of wire brushing it away? Or is there another technique for clean up, that will not scratch the surface?

Thanks

Bill
Attached Images
File Type: jpg 1.jpg (65.1 KB, 5 views)
File Type: jpg 2.jpg (78.8 KB, 0 views)
__________________
Bill Tromblay

"Remember, the camel was a horse, designed by a committee" My mentor and friend, Gil Zietz Micro Metric Machine.
Reply With Quote
  #2  
Old 10-22-2018, 11:39 AM
cvairwerks cvairwerks is offline
Member
 
Join Date: Dec 2014
Location: Justin, Texas
Posts: 85
Default

Bill: Might be worth trying some very hot water and a nylon bore brush on it.
__________________
Craig
Reply With Quote
  #3  
Old 10-22-2018, 12:14 PM
Marc Bourget Marc Bourget is offline
Member
 
Join Date: May 2013
Location: North Ca
Posts: 371
Default

I second that suggestion, observing it is close to what Kent White teaches in his advanced aluminum workshops.
__________________
Marc
Reply With Quote
  #4  
Old 10-22-2018, 12:15 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 & April '16
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,222
Default

Quote:
Originally Posted by BTromblay View Post
Hi,

The question is gas welding flux clean up. It seems that all the books I read, reference using a stainless steel brush for clean up post weld. I have heard that you can use vinegar, or hot boiling water as well.

...........
But can you soak the part in water for an hour or more to dissolve the flux, instead of wire brushing it away? Or is there another technique for clean up, that will not scratch the surface?

Thanks

Bill

The long standing tradition is to wash in hot/boiling water.
OR soak in hot/boiling water.
Wipe with a diaper or tampons, to avoid scratches.
(First problem I have heard about trouble rinsing off flux this way... )
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
Reply With Quote
  #5  
Old 10-23-2018, 11:38 AM
billfunk29 billfunk29 is offline
Member
 
Join Date: Oct 2013
Location: Minnesota
Posts: 220
Default flux cleaning

I like this cheap little steam cleaner.

https://www.target.com/p/bissell-174...E&gclsrc=aw.ds
__________________
Bill Funk
Reply With Quote
  #6  
Old 10-24-2018, 12:38 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 & April '16
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,222
Default steam cleaning flux residues

Good idea Bill.
The steam cleaning method also helps on brazing operations, where in industry it is a standard cleanup practice.
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
Reply With Quote
  #7  
Old 10-24-2018, 07:52 PM
BTromblay BTromblay is offline
MetalShaper of the Month August 2018
 
Join Date: Oct 2015
Location: Mukwonago, Wi
Posts: 303
Default

Hi,

I re-read my post and I don't think I was clear with my two part questions, the 1st one was answered.

1, Do you need to use a stainless steel wire brush to remove all the flux? Answers above, "no not needed, plastic brush with hot water would be fine." Great! (I have tried this, since this post and it works well)

2, Do I have to use "Hot Water" to remove the flux, or can I soak it in "Cold Water" for an extended amount of time? Overnight? My thinking is, if cold water washes off the flux, before it is welded, will it wash it off after it is welded?


I have a used 250 gallon Jet fuel tip tank repair for a Lockheed T-33, material 3003-H14 x .060". The damage area is in the skin, between two bulkheads with baffles and 5 feet away from the closest opening, (tank size 30"dia x 14' long). How do I clean the flux off the inside of the tank? The tank will be filled with cold water to the top, and welded, this is how I have always done it with TIG and I'm still here. Will "cold water" wash off the flux on the inside, or should I do some thing else? I cant get to the area, to steam clean the inside and I cant heat 250 gallons of water. I can TIG weld it, the goal is to Gas weld it.

Will hot water, get all of the flux out of a hem or wired edge? I have an original 1937 De Havilland Tiger Moth cowls and in the corners, the aluminum was welded over the steel wire. I'm not worried about welding the material, but can I get the flux out from around the wire? De Havilland was worried about getting the airplane thru a war, not about the long term issues, 81 years later. The panels have so much corrosion now, it is hard to tell if it is a flux issue or old age issue.

I'm building more and more oil and fuel tanks for customers, + airframe components like in the post. I use a tea pot now, to wash off my small parts with hot water, I just didn't like the stainless brush. Will look into the steam cleaner as well.

I can test my theory's, or thought I would ask the questions.

Thank you for the response.

B
__________________
Bill Tromblay

"Remember, the camel was a horse, designed by a committee" My mentor and friend, Gil Zietz Micro Metric Machine.
Reply With Quote
  #8  
Old 10-24-2018, 08:25 PM
steve.murphy steve.murphy is offline
Member
 
Join Date: May 2009
Location: Brisbane, Australia
Posts: 411
Default

I recall something about using a mixture of nitric acid and water to remove flux from welded aluminum where you cant get at the inside to scrub the flux. Maybe Kent will jump in here.
Another question is if welded using a gas fluxer would be OK to use for gas welding aluminum and if it leaves less flux to clean up.
__________________
Steve

śrugo nunquam dormit

Last edited by steve.murphy; 10-24-2018 at 08:26 PM. Reason: spelling
Reply With Quote
  #9  
Old 10-25-2018, 09:58 AM
billfunk29 billfunk29 is offline
Member
 
Join Date: Oct 2013
Location: Minnesota
Posts: 220
Default Cleaning options

A couple options for cleaning airplane parts. I have used ultrasonics baths, mostly flux removal on brazed pitot tubes. Most machines are 40 kHz, which have lots of power, but the 100kHz machines have smaller bubbles and penetrate pores better. Ultrasonic cleaning will blast holes in aluminum foil in less than a minute. Do a test piece first. Another choice is dry ice blasting. Our machine shaves off a block of dry ice and shoots it out like a sand blaster. Except no clean-up. The machines are expensive, but the principle is simple. Maybe a DIY project.
__________________
Bill Funk
Reply With Quote
  #10  
Old 10-25-2018, 05:26 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 & April '16
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 3,222
Default

Quote:
Originally Posted by billfunk29 View Post
A couple options for cleaning airplane parts. I have used ultrasonics baths, mostly flux removal on brazed pitot tubes. Most machines are 40 kHz, which have lots of power, but the 100kHz machines have smaller bubbles and penetrate pores better. Ultrasonic cleaning will blast holes in aluminum foil in less than a minute. Do a test piece first. Another choice is dry ice blasting. Our machine shaves off a block of dry ice and shoots it out like a sand blaster. Except no clean-up. The machines are expensive, but the principle is simple. Maybe a DIY project.

Vibrasonics work nicely - on some parts, for sure.

Before dry ice came along it was soda blasting, and before that it was walnut shell. Dry ice has been the go-to for a couple decades now - (dating the tech is a bummer for me, as time goes too fast, Bill.)


I rinse my welded tanks with 25% phosphoric after a hot water rinse, and that seems to clean up flux residues very nicely.
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 07:26 AM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.