Aluminum Soldering / Brazing Questions

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Am hoping to hear from any one that's done any soldering or brazing of aluminum to get some guidance or suggestions. I've been using TIG welding in building some heat sinks for electronic components.  While I've made around 10 of them so far in different configurations it's been some what problematic and labor intensive.   I've started to wonder if may be soldering or brazing might be a possible better option but have never really done any before and would like to hear from any one who might have prior experience with it.   These heat sinks are made from 4" square, 1/8 wall aluminum tube that has had a series of slots cut on one face to allow 1/8" thick aluminum flat bar to slip in to make internal fins.   Instead of TIG welding these fins in place I'm hoping it might be possible to solder or braze them in.  Ideally I'd like to be able to clean, flux and pre place the fins and brazing alloy and then place the whole assembly in a oven, bring it up to the required temperature and have the alloy melt, flow out and bond all in one go.   Here's some pictures to give you an idea of what they're configured like.
Reply:4956,You can oven braze those just like you described; but you'll need some specialized equipment to get the job done.  The filler can be purchased as thin strips and the flux is a powder or paint on liquid.  The big issue I'd be concerned with is that sort of brazing is done in an inert atmosphere or vacuum furnace.  You'll likely need to find someone to handle this part of the work.  Likely candidates are shops that do production brazing already; and they should be able to help with the filler strip and flux.Automotive radiators and heat exhangers are brazed using ovens.  There may be newer technology that I'm unfamiliar with that would all brazing in normal atmosphere....One more thing to pay attention to is that some of the fluxes can be toxic and/or they may contain fluorine.  So after the brazing is done you may need to spend some time cleaning any flux residue out of the assemblies.  The Fluorine residue can combine with moisture in the air or condensation and you'll get HF acid that will corrode the parts.  Might or might not be a cosmetic problem or a serious structural problem.  It all depends on the environment and end use(heat cycling, high relative humidity, etc.)Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:I'd be concerned that the thermal condutivity of the solder is not as good as the TIG weld.  Could that hurt the heatsink performance?
Reply:There is an aluminum brazing rod that is done with mapp gas torch. I've used it for filling holes drilled in truck boxes a and other non critical joints. I picked up a 1lb tube at harbor freight just to see how it worked. If you google search hts 2000 you can find more info about it it might work for what you need.
Reply:Here's a link I found that might answer any questions you have. ► 6:06► 6:06Nov 28, 2012 - Uploaded by aluminumrepairNow anyone can repair aluminum, cast aluminum and cast iron with our brazing rods used with ...
Reply:Gentleman,Thanks for the input.   While I can see where the product in that video would have it's uses this one might be better suited for what I'm trying to do.