Aluminum Dip Brazing Help

By kgroth Date 04-18-2006 19:13

We have recently set up a Aluminum dip brazing line and I am using a 5356 rod to TIG parts together prior to dip brazing. The problem is that I seem to get some cracked welds after brazing even though I preheat the parts prior to TIG welding. I see the 4047 filler metal mixing with my 5356 during the TIG welding and wonder if it is contaminating it?

Are there any dip brazers out there with a better method for holding parts together? What' the best rack and spring material?

If anyone could help I would be greatful.

Thanks

Ken

By sean.therrien Date 10-03-2007 11:53

Ken,

What material are you brazing? 6061? 6063? something different.

For 6XXX, we find 1100 wire works best.

YOu can also use a few different designs for putting the peices together. If you have a stable tab and slot configuration that can be used for self fixturing, you can use a prick punch or staking to hold the parts together witht eh proper gap and then just weight the parts down with a light fixture to keep it from possibly floating in the flux.

Otherwise, fixturing will depend on the size, complexity and shape. It can be as simply as using perferated stainless steel with a light spring on the outside edges. Complex stuctures can use dozens of plates, springs and other fixturing techniques.

In short, there is too little info on what you are trying to acheive.

Sean