Originally Posted by
Lugy
....Any suggestions? Bearing mind the large quantity that will be coming shortly!
The bowing is almost certainly due to stresses in the material, I have run into a similar problem using 4" x 1/4" 6061 flat bar.
Given the quantities you are looking at my suggestion is to find someone who can anneal and then re-temper your material before machining. This is not a difficult operation and involves heating to around four hundred degrees C followed by water quenching then re-heating to around three hundred degrees and holding it at this temperature for a few hours.
An open mind is a virtue...so long as all the common sense has not leaked out.