Tig weld rack and pinion to cnc plasma frame?

[warwick]

hi, im building a cnc plasma table, its constructed from 80x80x6 box section, with 80x80xx6 angle running along side the y axis to support the linier rails.....

im using rack gear system to drive it.....

Can i tig the rack onto the angle rather than drill and tapping? also, i want the x gantry to be able to extend outside the table so i can cut large diamiter pipe.i was thinking of using a piece of link pallet racking to make the gantry,it being light and strong