Ask your WELDING questions here.

[KTM640Dakar]

Originally Posted by pablo83

I took the liberty of snooping through your SmugMug account to get some better pictures of this project. You clearly know what you're doing when it comes to metal work. If you haven't seen this thread, I think you would enjoy it. I know the guys who watch that thread would love to see your formula one red wagon, as well as all your other projects.

Anyway, back to your question. Here's a better picture of the welds:



It looks like the BMW welds are done with some specialized welding style, but I could be wrong. My guess is they are brazed. I've seen tubes joined in a similar fashion on a bicycle frame. I don't know how it was done, but I was told it was done with a TIG welder and brazing rod. Another possibly is SAW (although I've never seen fish-mouthed tubing done with SAW). The last option I can think of for this type of weld is dual-shield, although dual-shield is usually done with much larger pieces (like bridges and pressure tanks).

I think it's going to be real difficult to make identical welds in a small shop unless you really want to do a lot of research into bicycle frame brazing. But I do think you can greatly improve your welds to the point that only a handful of people will notice the difference. First. you're putting two tacks per tube. This makes a very bumpy surface to weld over later:



Try using one tack in the center of each tube. Next, remove the rack from your jig and tack the back side of the tubes (single tack on each). Then do each final weld in a single pass. Reducing your heat will make the weld stand up more, but you need to be careful that you're still getting good penetration. I think this will make your final welds much smoother.

If this doesn't get you where you want to be, look into getting a tool that will allow you to fish mouth the tubes (it looks like your tubes are straight cut)



This can be done with a small lathe (screw making type) or other jigs like this:



Also, this is going to take a lot of practice before. I've spent many years joining tubing in projects like this and it probably took many hundreds of welds before I could lay down a consistent and good looking weld on fish-mouthed tube. Doing it on small tube is going to be even more difficult.


You've built some significant jigs for this rack. Are you going to do a production run of these racks?

Those BMW racks are welded with robots. They get programmed to make a nice steady weld. Almost impossible for a human hand to make welds that consistant...almost.

[fxstbiluigi]

Originally Posted by KTM640Dakar

Those BMW racks are welded with robots. They get programmed to make a nice steady weld. Almost impossible for a human hand to make welds that consistant...almost.

It is a good thing you added that last "almost". You haven't been aroud many experienced weldors have you?

[KTM640Dakar]

Originally Posted by sailah

I've just recently gotten my SP-150 Lincoln up and running. I bought a new gun, new spool of 0.030 wire and a new tank with 75/25.

I'm running the gas at 25cfh. I talked to a metal fab guy this morning who laughed at that and said 3-5 is all I need. Lincoln and Miller websites all say a lot more than that. Anyways, my 55 cf tank is pretty much gone. Costs aside, is it bad to have too much gas running?

My problems are that I am getting a lot of popping.

I have a volt meter on the welder, but its hard to watch. Maybe I can shoot a video with my camera and check to see what voltage I am getting. For 1/8" steel, what should I be getting? I've also played with the wire speed anywhere from 200-300 and I am all over the map.

I usually get good penetration, but I never get the bacon sound people talk about.

Gas too much? wire & amps suggestions?

Here's the welder in question.

Turn up your voltage. Try 200 on the wire feed and 20 Volts (approx 5) on the knob.

[sailah]

Originally Posted by KTM640Dakar

Turn up your voltage. Try 200 on the wire feed and 20 Volts (approx 5) on the knob.

Timely post. I can't say what's happened but here goes. I switched out the 0.030 to 0.035 today. I turned down the gas. On 3/16"tube I'm getting great welds, g ood penetration and the popping is gone. Sounds just like the guys on tv

My settings are about 6 and260 wire feed

[Pablo83]

Originally Posted by KTM640Dakar

Here is a Lincoln Hydrogard rod oven. Holds 10 pounds of 1/8 rod and plugs into 120V. Part number is K2829-1 from Lincoln.
http://content.yudu.com/A1pk9y/LinEl...sources/73.htm

I needed something that would hold more than 10 lbs. I found a guy selling a DryRod unit on CL for $170. I had to drive a couple hours to get it. It had been dropped and had a large dent in the back. I took it apart and reshaped it with body hammers. It seems to be a solid unit. I'm not sure why the PO had to write "No Food" on it; kind of scary.



It barely fits on the top of one of my shelved. It was a real pain getting it up there by myself.

[fxstbiluigi]

Because people have been known to warm up burritos steak and various food items in rod ovens.

[grizzzly]

Originally Posted by pablo83

I I'm not sure why the PO had to write "No Food" on it; kind of scary.

what part of oven are you not understanding

you probaly think that it would be strange to take a peice of 1/2 plate and make a pass of two with something like 1/4 7024, to heat your lunch

BTW just out of form please find another place for you butane bottles

[fxstbiluigi]

Everything around the Burrito warmer should be moved some where else. What type of rod do you intend to store in there? and what temp do you have it set at? Plastic can melt spilling what ever, eventually cardboard can become hot enough to ignite.
Just a lil humor, although it wasn't funny at the time, I was working at a power house where welding rod was a controlled substance, portable rod heaters went with the weldors and rod was checked out by the pound and when turned in rod stubs were counted and what was still in the portable heater weighed.
I wraped a steak that I bbq'd the night before and warmed it up in the portable rod heater for lunch for my fitter and I
well some of the juice leaked into the heater. and you could smell it.
so when I turned everything into QC that evening I just dropped it off and left, not supposed to do that, QC smelled the meat and was instantly pissed.
The next day I wasn't allowed to draw any rod and got fired.

[sailah]

So I ran my first aluminum beads this morning on my inverter welder.

I had a instructor type show me the basics. First off, I didn't clean it very well as I had forgotten to get a SS brush and just used a regular wire brush. Second, the base plate was pretty thick. I had the pedal floored the whole time

AC balance was set about 35-40%, argon about 10. 3/32" green tungsten, balled.

Any ideas what the sand stuff is? This was my first and only bead, I plan to do a lot more to get more of the stacked look. I'm def getting good penetration.

[Pablo83]

Originally Posted by grizzzly

BTW just out of form please find another place for you butane bottles

what's wrong with my bottles? They're unopened.

Originally Posted by fxstbiluigi

Everything around the Burrito warmer should be moved some where else.

Where's everyone's since of adventure? The oven is well insulated, it's not like the surrounding stuff's getting hot.

Originally Posted by fxstbiluigi

What type of rod do you intend to store in there? and what temp do you have it set at?

mainly 7018 and 7024. 125 deg. (the plastic seems stable)

[Poolside]

Originally Posted by sailah

So I ran my first aluminum beads this morning on my inverter welder.

Any ideas what the sand stuff is?

Nice job. The white sand is aluminum dross, aka: sapphire.

[sailah]

Should I be doing anything about it?

And can I sell the sapphire for anything

[Poolside]

Originally Posted by sailah

Should I be doing anything about it?

And can I sell the sapphire for anything

I can't remember seeing an aluminum weld without it. Some folks get all crazy with various pre-weld cleaning procedures, it's like different religions. Unless the pre-weld surface oxide removal, from both the part and the filler rod, followed by the welding, are both done while the part remains inside an inert gas chamber, I can't see how the dross isn't formed. Without the inert environment, the dross can be minimized but not completely eliminated by cleaning and wiping the part and filler rod directly before welding. Use mechanical means to remove the dross after welding, then follow with surface finishing for the desired end result. Or just leave it as is.

[fxstbiluigi]

Originally Posted by pablo83

what's wrong with my bottles? They're unopened.



Where's everyone's since of adventure? The oven is well insulated, it's not like the surrounding stuff's getting hot.



mainly 7018 and 7024. 125 deg. (the plastic seems stable)

250*f is the recommended temp for storing 7018 & 7024 .

[Pablo83]

Originally Posted by fxstbiluigi

250*f is the recommended temp for storing 7018 & 7024 .

Thanks. Do you think that will be too hot for my burritos?