first time welding - new back section

The last time I posted my bike, I chopped some things off and started messing around with it.

Now, I cut off some more of the frame section in the rear and ended up reusing a piece of the cut off frame section to tidy up the rear end.

Not sure what I plan to do with the lower holes yet, but I tried to fill in a bit of the section where the two pipes meet (then my sanding disk disintegrated).

Let me know what you think. A battery/electrical box is next.

I love welding.

 

Good work for the first time, although I'm no expert myself. I love welding. Did a bunch to my frame last month and will be doing parts of my exhaust and a new battery/electrical box this weekend.

Keep up the good work!

 

What are those crevices in the weld?

 

johno8 - I'm assuming you mean in the first pic? The cut in half flange at the bottom acted as a sort of gusset for supporting the rear section of the frame. When they welded that to the frame section, it's as if they just folded that piece of metal over itself a few times first. When I cut the frame off, the cross section of it looked like (and this is sideways): O))> The O being the frame. The crevaces are from where I built up a layer of weld to fill in between the pieces of metal and the new back piece.

I got tired of wasting wire, as there's going to be a piece covering that anyways, so I didn't fill them in all the way.

 

Gotcha...I'm a beginner with welding as well and I sometimes get those things too. Appreciate the explanation!

 

I'm not an expert welder but I can tell you this, take your time when welding the frame. Your life depends on it.

If you want welds evaluated you need to show the welds before grinding them. That way an experienced welder could tell you if the heat and wire speed is correct for a Mig if thats what you are using. You have to ensure the weld is penetrating the steel and not just sitting on top of the steel.

If using flux core wire make sure you clean the welds when you stop and start.

You should have nice v beads in the welds also. The length of the V in the beads will tell you if your too hot or too cold.

Tack the pieces together and then weld them up.

Your machine should tell you a starting point setting for the type and thickness of steel you are welding. You will have to run a couple of beads on a scrap piece of metal of the same thickness steel to set the machine up.

Practice, Practice and Practice.

 

judging by the first photo....those voids in the weld look like porosity or maybe slag inclusions if you were using flux cored wire.
There are so many variables in welding so it is difficult to say what caused
it....but it's definitely not something you would want to leave there, especially on the frame. Those voids can easily turn into much bigger cracks. After you grind a weld, all you should see is shiny metal, no cracks, pinholes and absolutley no voids. If I was you I would grind out those little void spots some more and go over them again.

For a first time welder it looks pretty good though.....keep at it

 

Cool, thanks for the advice. I'll most likely end up going over it, I just wanted to get it in place and welded up. I'm surprised it holds so well, I can lift the bike by the back bracket (well, surprised at my welding skills).

Ward333 - yep, I was using flux cored wire. I got a great deal on a flux core welder from HF and couldn't pass it up. After clean up, I'm surprised how well it all looks.

 

Hey Mestnii, cool to see this post. I started welding to chop my bike a few years back, same as you're doing. Now I work doing metal fabrication. It's addicting, ain't it

 

Just a little tip..

Cover your tyre with something when you weld.. Molten metal has a habit of melting its way through and you'll end up with a bill for a new tyre fairly quickly.. (Experience!!)

 

My problem was with the grinder getting awfully close to the tire. I also just found a metal shelving unit I can take apart and make a fender with. I'm going to just make a dedicated build thread for this.