T and lap joint advice please

[Richard.]

It's hard to tell from the pic but there does look to be an inclusion there.
I always etch with methanol and 15% nitric acid. (Do not add the acid to the methanol) always the other way round.
I will put some of my etching with this solution up so you can see

 

[Richard.]

Rutile flux core wire open root with ceramic backing in the 3G position. Low hydrogen (basic 7018) electrodes multi pass in the 2f position. I also got a small inclusion with the first pass which deemed the whole trial piece no good. This was done under strict inter pass temps this is a sub arc root and filling pass with twin wire. We were testing slag detachment in the root. Which if you have ever done SAW you will know can be a nightmare. Tig weld carbon steel round a cylinder in two passes.
As you can see I have not milled or surface ground these but the etching is still clear with a good old sand and polish.
I also lacquer them when they are etched to bring it up nice.

 

[rockweasel]

The lime juice eventually worked. There is a distinct colour difference. It's the fillet weld on the top in this photo.

 

[JDJones]

Hi Richard,& rockweasel
GREAT, As Punch said "That's the way to do it" Good shop floor on the job testing Des