[bigworm40]

So I kind of posted this in another topic but it seemed to get skipped over. Soon I will be doing a great deal of tee joints of 1" A572 grade 50. Because of the size of the weldment its going to be tough to run all horizontal stringers so some of it will have to be done in 3g position but i should be able to avoid over head. with that said, I have no input from the designer or the engineer on welding specs. so with that said can anyone give me some advice on chamfering, what angle, what size? My intent is to just chamfer everything rather than worry about what needs it and what doesn't. Is there a standard?

Material A572 gr 50
Machine Miller 252
Wire Lincoln Ultracore 71A85
Gas 75/25

[weldin mike 27]

The correct term is "weld preparation" a chamfer refers to a small 45° cut to finish a machined item. But anyway, to your questions, so you want to turn it from a T fillet weld in to a combination T fillet/butt? Right? If you can get at both sides of the plate, a 10mm x45° on both sides, (a double bevel) that would leave a 5mm land/root face. Would be a good start, however take a second to consider how strong 12mm/ 1/2" fillets will be. That will be very strong without any further propping.

Just remember to allow for a root gap so the plate has room for shrinkage, to aid the prevention of lamilar tearing. (where the shrinkage stresses tear the bottom plate, under the weld, bad news)

[bigworm40]

If you can get at both sides of the plate, a 10mm x45° on both sides, (a double bevel) that would leave a 5mm land/root face. Would be a good start, however take a second to consider how strong 12mm/ 1/2" fillets will be. That will be very strong without any further propping.
Just remember to allow for a root gap so the plate has room for shrinkage, to aid the prevention of lamilar tearing. (where the shrinkage stresses tear the bottom plate, under the weld, bad news)

So if im understanding you correctly you think i would be fine with just running 1/2" fillet welds with out double beveling?

[weldin mike 27]

Depends on what it is. It'll be very strong with full fillets. Have you ever tried to cut apart something that's fully fillet welded? It's an awful lot of work. Massive lifting lugs are welded with fillets only, as well as lots of structural stuff. I'm disappointed in your engineers. You're are scared that you'll Under-weld it, but in all likelihood you'll make it many times stronger than need be. What are we talking about here, anyway?

[bigworm40]

It's difficult to explain with out pictures but due to Patten issues I can't post full shots but ill try and get some general shots so you can see what I'm working with. And no I've never tried to cut apart a full fillet welder member. Thanks for you input I'll try and get a picture or two.

[bigworm40]

A few pictures of the weldment in question.

[weldin mike 27]

I shouldn't really offer an exact answer, as I'm not qualified. How ever, anywher where there is room for a fillet, it will work fine by itself (without prep) where there is no room for the weld leg, yoy will have to prep a bit. At least as much as the size of the fillets you decide to do, ie: 10mm fillet, 10mm x45° bevel. (the minimum for a single bevel) personally I'd slap the engineer until they came up with details. Then all yoy have to worry about is following instructions, not making them. (another rule I've heard is fillet welds should be at least half the thickness of plate....1" plate = 1/2" fillets. Minimum. But that depends on end use.)