Welding question on BIY

[Arbo]

Brazing with either brass or aluminum alloy is a fairly common manufacturing solution to joining dissimilar metals. Not as strong as welding so not useful for butt joints but can be extremely strong with a tab or overlap joint. Brass is most common filler but there are quite a number of specialized brazing rods used industrially.

Whereas welding is essentially just adding more of the same material and is therefore the same strength as the base metal, brazing is surface bond. Brazed joints can be practically as strong as the base metal but require larger surface area to get that strength. Nice thing about brazing is that it can be done with propane Sonia cheap and convenient.

Cool! I think I will bid on that ocean front property in Arizona that Achmed offered me on that craigslist email too.

 

[IslandTractor]

Are you saying that you don't think brazing is an effective way to join dissimilar metals??? Read a bit before bringing on the sarcasm. While Aluminum to steel brazing is not common (bolting or gluing are more practical and a bimetallic strip is used in ships etc), there are brazing rods made for aluminum and the two metals can be joined that way. We don't have any idea what the OP wants to do so I don't know if it is practical or not but the techniques exist.

 

[sal64]

Are you saying that you don't think brazing is an effective way to join dissimilar metals??? Read a bit before bringing on the sarcasm. While Aluminum to steel brazing is not common (bolting or gluing are more practical and a bimetallic strip is used in ships etc), there are brazing rods made for aluminum and the two metals can be joined that way. We don't have any idea what the OP wants to do so I don't know if it is practical or not but the techniques exist.

i have never heard of brazing alum to steel.

 

[IslandTractor]

i have never heard of brazing alum to steel.

It cannot be done with the standard bronze brazing rods as aluminum melts before bronze but there are aluminum or zinc type alloys that are used in place of bronze. I don't recall the composition of the rods but they are available via Internet. I don't know if brazing would be practical for the OP as some skill and experience with brazing is also needed and we don't know what he is building. As noted earlier, joint type, design and fit are more critical for brazing than with welding so it might well be impractical. Bolting, riveting and epoxy would be more common. Also, in general it is not a good idea to directly attach aluminum to steel as galvanic corrosion will be an issue.

 

[rgs03833]

It cannot be done with the standard bronze brazing rods as aluminum melts before bronze but there are aluminum or zinc type alloys that are used in place of bronze. I don't recall the composition of the rods but they are available via Internet. I don't know if brazing would be practical for the OP as some skill and experience with brazing is also needed and we don't know what he is building. As noted earlier, joint type, design and fit are more critical for brazing than with welding so it might well be impractical. Bolting, riveting and epoxy would be more common. Also, in general it is not a good idea to directly attach aluminum to steel as galvanic corrosion will be an issue.

Thank you for clearing some stuff in my head up. So my best option would just BOLTING them

I always see people have Welding them on their Tractors, Boats, Motocycles... Maybe it's Steel Diamond Plate?

 

[IslandTractor]

Thank you for clearing some stuff in my head up. So my best option would just BOLTING them

I always see people have Welding them on their Tractors, Boats, Motocycles... Maybe it's Steel Diamond Plate?

I'm sure that 99% of diamond plate you see on tractors is steel. No advantage to more expensive aluminum on a tractor. The dissimilar metal issue causes more problems than just bonding too so unless there is a real advantage when you need lightweight or rustproof material, painted steel is best.

 

[Soundguy]

Really? Let me know how that works for you.

quite easy.. just takes a lil patience and 2 different solder alloys to do it.

I soldered or 'brazed' a piec eof aluminum bar to a piece of steel angle.

clean wire wheel to each piece.

lots of flux on each piece.

tin the steel with silver solder.. set aside..

use a alloy solder rod, such as alumaloy and tin the aluminum. ( note.. all the allow solder rods I used were MOSTLY zinc.. so this should give you a clue as to why it works.. )

once the aluminum is timmed with the zinc allow rod, then you can tin that zinc alloy patch with silver solder.. then you can join that bar stock to the angle iron and heat the joint like sweating a pipe and the silver solder on the angle will join witht he silver solder on the zinc path and flow.. and then you let it cool.. and poof.. you have soldered aluminum to steel using 2 steps and 2 different fillers.

works especially easy on zinc plated steel.

here's a pic I made for some unbelieving friends that called me aliar when i described the above process. that long bar is aluminum stock. on the end is some scrap angle iron.. then a piece of copper pipe, thena tin tab.. then a bright zinc bolt.

soundguy

 

[Soundguy]

Are you saying that you don't think brazing is an effective way to join dissimilar metals??? Read a bit before bringing on the sarcasm. While Aluminum to steel brazing is not common (bolting or gluing are more practical and a bimetallic strip is used in ships etc), there are brazing rods made for aluminum and the two metals can be joined that way. We don't have any idea what the OP wants to do so I don't know if it is practical or not but the techniques exist.

I agree with you 100%.

try it before being sarcastic.

I posted some pics below of a mock up i made for some 'friends' that said I was full of ^&*(.. then I proved em' wrong... )

as you point out.. there are some nice mostly zinc, alloy rods that will melt and join to aluminum.. from there.. it's pretty easy to get lots of different metals to stick to zinc...

when dealing with the non believers.. i always keep in mind the old addage about science being like magic to those that don't understand it.

soundguy

 

[rgs03833]

quite easy.. just takes a lil patience and 2 different solder alloys to do it.

I soldered or 'brazed' a piec eof aluminum bar to a piece of steel angle.

clean wire wheel to each piece.

lots of flux on each piece.

tin the steel with silver solder.. set aside..

use a alloy solder rod, such as alumaloy and tin the aluminum. ( note.. all the allow solder rods I used were MOSTLY zinc.. so this should give you a clue as to why it works.. )

once the aluminum is timmed with the zinc allow rod, then you can tin that zinc alloy patch with silver solder.. then you can join that bar stock to the angle iron and heat the joint like sweating a pipe and the silver solder on the angle will join witht he silver solder on the zinc path and flow.. and then you let it cool.. and poof.. you have soldered aluminum to steel using 2 steps and 2 different fillers.

works especially easy on zinc plated steel.

here's a pic I made for some unbelieving friends that called me aliar when i described the above process. that long bar is aluminum stock. on the end is some scrap angle iron.. then a piece of copper pipe, thena tin tab.. then a bright zinc bolt.

soundguy

Thank you Soundguy :thumbsup: Picture is PERFECT!

I guess I'm gonna have to try it

 

[Soundguy]

you wouldn't believe all the naysayers.. some called me a downright liar.. some stupid. some said I faked the pis.

so I took like 20 pics showing the steps, using the propane torch, clenaing.. soldering step 1,, soldering step 2, and then joining all the dissimilar metals to that one aluminum bar, then inverting it and what not to show it was not a trick of angle or some thing.

mind you this is a slder connection and as such is only as strong as the filelr metal..e tc.

Lots of oil pickup tubes in old tractors hav ethe tube silver soldered into the pump.. so hard solder on steel, I alrady have done / had good practice with. and those allow solder rods that are good for aluminum and zinc alloys.. well.. once you read the rod contents you know what you can do.. ones I have now ar emostly zinc, with some aluminum..e tc.. couple other metals inthere too.

knowing what all zinc will stick to lets you in on what you can and can't join.

havn't had much luck with chrome yet