Aluminum Welding Question

[Sroufe7]

I will be welding 6061 fuel injector bungs onto a cast aluminum intake manifold.

Are there any tricks in doing this?

I have not tried something like this, nor have i done much aluminum welding. I am working on getting a BUNCH of stuff to practice on. Do have a few extra cast aluminum manifolds to practice on, just need to get some material to weld to it.

Thank you for your input.
Scott

EDIT: will be using a tig welder. 4043 filler rod work ok for this? It seems to be the most common filler rod out there.

[Sroufe7]

no one is willing to give me some tips?

I have practiced quite a bit. Welding 2 brand new pieces of aluminum together and getting the hang of it. I do have a few spare/junk cast manifolds I can practice on, which will be next thing i do.

[root]

I can't help you as I have never welded anything, however auto projects is what is leading me to want to learn. I'm curious what car the manifold is for and which welder you are using?

[mooseye]

I would suggest you do a search in this forum for aluminum welding as there is a plethora of information already posted.
It may get you more response if you post what machine, gas, polarity etc. that you are using.
It sounds like you already have some knowledge of the process if you are practicing. Maybe some pictures of your efforts if you have that capability.

[Sroufe7]

Using a Miller Dialarc HP-F, 250 amp watercooled torch, 100% argon (is there any other gas you would use with a tig welder), 4043 filler rod.

I have searched, but didn't find much on the subject of welding to an automotive manifold before.

I am working on doing an 8 injector setup for a dodge avenger.

I need to weld 4 fuel injector bungs into the lower intake manifold. These injectors only are used while under boost, this vehicle is turbo charged.

I will post up my last welds a little later once I go back out in the shop.

Thanks
Scott

[jamscal]

Without seeing your setup, I would have a step on the OD of your bungs...that way they would drop in the holes in the manifold and you could weld around the perimeter. Sort of a positive locator for them.

I'd practice a few on a spare manifold and see what happens.

I'd say the intake runners are about 1/8" wall...I'd start with 170-180 amps and go from there.

Make sure everything is very clean, tack and go.

Good luck, and I'l like to see pics.

-James

[Sroufe7]

First i lap welded the 2 pieces together, then I welded the top piece standing straight up.

[Sroufe7]

problems I think I am having:

To small of tungsten (1/16th green tip and gold tip) I am waiting for my parts to get there. I ordered 3/32" stuff along with a bunch of other stuff.

I am welding at about 120 amps or somewhere close to that.

Seems if I use more amps, it over heats the tungsten and starts to melt away. This is the reason i ordered a kit which comes with all 4 common sizes (.040", 1/16th", 3/32", 1/8").

I did order some grey tip tungstens to try out.

I won't be able to have a lip inside the plenum, I do not believe. Because the bungs have to go in at a pretty good angle, they are not going straight in.

Thanks for the input!

[TJS]

The thing with welding 6061 to cast is clean clean clean. Some even have used just the TIG torch on a lower heat setting and going over the cast area to lift the impurities out and then brushing with a stainless brush and acetone(you will see the black specs rise as you go over with the torch). Your practice pieces looks as if you did not clean them. As all aluminum welds, brush with a dedicated to aluminum stainless brush and wipe with acetone. Also wipe the filler rod down with acetone. As for filler you might want to try 5356 filler. I would suggest a lot more practice before attempting your manifold project. Also I do not know what your post flow is but you might want to see if your post flow time can be increased. This will prevent your tungsten from burning up. Some also have heated the manifold in an oven to about 300 degrees before welding.
T.J.

[Fat-Fab.com]

By looking at the samples you have given you are not ready to weld on a fuel system. Sorry


Comments about your welds, vary inconsistent travel speed.

Here is my description of the process I go through when welding aluminum.
First all parts clean and free of oil dirt burrs ( cast surface is heated gently and scrubbed with a stainless steel brush)

Parts are placed clamped is better, strike an arc develop the puddle to about 2/3 the size I want the finished weld. you may need to dab a small amount of filler at this point just to get the parent metals to join. I would do this step on opposite sides of each bung.
During this time the part is preheating go back to a point 90deg off one of your tacks and establish another puddle develop it to full size by adding filler and heat at this point things happen real fast you start the torch traveling and you start adding filler. Travel speed is going to be in the 2-4 inch per minute range. Dabbing the filler in at a rate of two dabs per second.


Like I said things happen fasten fast. I am constantly adjusting the amps with my foot, my foot doing the majority of the work to control how wide the weld is. All this time you also have to keep the tungsten at a constant distance from the work and at the appropriate angle to the joint (sometimes this means pointing it more to one parent material than the other).


Going around a small item like 1/2"-1" dia. is one of the hardest welds you can make in that you are working with a vary small part that gets overheated vary easy.

You are not ready sorry do some more practice and get back to us with more pictures

Good Luck

TJ

[Sroufe7]

Sorry but I never said I was ready. That is why I posted on here to get tips and pointers.

I will not attempt to weld the manifold until I am very comfortable.

I do clean the metal with an aluminum only stainless brush. I have never wiped the metal down with anything or the filler rod.

I have heard about preheating the metal in an oven, but I was told with this thin of an object, I shouldn't have to worry about preheating.

When I am welding is when I was having problems with the tungsten getting so hot. I think it was because it is to small for the amps I was using at the time.

Again, thank you for the pointers. I will post more pictures up later.
Scott

[TJS]

Keep practicing. Yes clean is the key. Also when you wipe your filler with acetone you will be amazed at the black at the cloth you used to wipe. Might want to get some scrap round stock alum. or old alum fittings and clean them up and try welding them on some flat stock the same thickness of material. The rule of thumb for amp settings is for ever .001 (one thou) you need 1 amp. Thus 1/8" is .125 so a starting point will be 125 amps. I use about 135 to 140 for 1/8" and control the heat with the pedal. You might want to search on grinding tungsten, argon flow settings, and cup sizes.
T.J.

https://www.tjsperformance.com

[Craig in Denver]

You have a good puddle, so I think the 120 amps is OK.

Your 1/16th is too small for that alum. The 3/32 will be right.
Include a picture of your tungsten, if it's not a flat gray color. Some guys can tell something from that. (if it's blue, turn up the post flow)

I let my square wave do most of my cleaning, that works well enough. BUT, you have porosity or impurities in all of your samples; something is wrong. Maybe you can turn the balance up, favoring the cleaning half of the cycle. I don't know if your welder will do that. The gray path along the sides of your welds is very narrow, showing low cleaning.

TJS said something about lifting the impurities out of the casting. As a hobby welder I've never been exposed to cast; but this could be VERY important. I did read something in a boating magazine that said your puddle should be wider into the casting; that will give a good mixture of your 4043 into the casting.

PS Your tungsten must NOT have a little bulge, just above the ground tip. This is caused by dipping your tip while welding. This would cause the porosity. Break off the bulge and regrind. When I do this, my arc turns green.

[mooseye]

Not knowing your background, I am going to take a guess that you are running this like you would steel or stainless steel. That is, you are welding over the wire. I find this very difficult on aluminum.
The technique I use is to get the puddle going as someone suggested and then dab your filler in. Move the arc away from the wire feed side and you will see what looks like a small keyhole. Keep this keyhole molten and dab your filler into it under the arc to form another puddle. Then continue this process all the way around or across the area to be welded. As has been stated, this happens at a fast pace and you must keep moving or you may see your manifold develop a large hole where you want a weld bead.
I find this method makes it much easier to control the bead size and shape.
I hope you do have a foot or finger amp control as aluminum requires less and less amps as the weld progresses.
You are correct in thinking that you need at least 3/32 tungsten for 120 amps. The gray you have ordered is able to take more amperage so you might be able to use a smaller size for greater control.
And as others have said, practice..........! and Clean!

[HMW]

I've welded lots of cast aluminum and it always has impurities in it. You'll see it burn out. Like TJ, I often heat it some, then brush off again with stainless brush. Of course there are a ton of different cast and some have more crap in them then others, good luck keep practicing.

If your using a transformer machine you should have a nice little ball at the end of the tungston. I believe an invertor machine will keep the point, at least it did when I demo'd one