Finishing inside corners?

[Bigger Hammer]

I'm in the process of finishing up a dog gate for my house. I built it out of 1" square tubing scrap that I have in the pile. I put the tubes together in a few places creating 45* joints. My mig gun doesn't fit down in the joint close enough to make a nice pretty weld and I wanted to grind them smooth anyway. Any suggestions on grinding tight inside corners where a grinder can't fit?

I was actually thinking about just using some bondo to make a radius in the corner and use a piece of round rod with some sand paper to pretty it up.

[russlaferrera]

You may be able to use a cut off disk, a rattail file, 3/16 end mill.

[PAToyota]

For what you are doing, welding the other three sides is more than enough for the "structural" needs and a bit of bondo to finish up the inside corner won't harm a thing.

[Bigger Hammer]

For what you are doing, welding the other three sides is more than enough for the "structural" needs and a bit of bondo to finish up the inside corner won't harm a thing.

Yeah, I wish I would have thought that through a little bit more before welding it all the way around. I wasn't concerned with the strength at all but thought I could do something pretty with it after boogering it up. I'll post some pics of the rookie bondo job when I finish it tomorrow night.

Does a TIG allow you to get into the tight corners better?

[PAToyota]

You can still have issues with the TIG gas lens interfering, but it is often a lot easier to do a clean job with TIG over MIG in close quarters.

[Aceman]

Use a die grinder on inside corners.

[v8garage]

Use a die grinder on inside corners.

With a burr bit.

[5wndwcpe]

In this senario, I'd sandblast it and use lead instead of bondo. After tinning, the lead will stick to the base metal whereas the bondo will most likely crack and fall out over time from the flexing of the corner. Plus, the lead won't be affected by moisture.