Cutting Straight

[Paul.]

I wouldn't bother using a straight edge for cutting, if you dont have a steady enough hand to follow a line, then all that will happen is you will either wander away from the guide or cut into it, I cut a lot of sheet with discs and with practice (and after the burr is removed) you would be pushed to tell the difference between a disc cut and a sheared edge.
Just let the disc do the work and watch the line not the tool,
And as for marking out with chalk and felt pens, that may be ok for rough work but for me the only way to mark sheet for cutting is with a scriber.

 

[Member 66061]

Cut forewards (away from yourself) so its easier to see the line and follow it

 

[baconbarm]

I personally find that the bigger the disc the better.
With a 9" grinder once the disc is in situ between either side of the cut steel, it's harder for it to veer off line

 

[mpats]

As has been said, nice clear line, I've been using a blue sharpie or french chalk (whichever I can find in the mess ). Move slowly away from yourself gently leaving a light score line on the sheet then start again and start deepening it. I really like a 1mm cutting disk on the makita 5" grinder as you can hold it easily in 1 hand and steady yourself or the work with the other. Get some scrap and have a bit of practice, might help.

 

[roofman]

Don't set fire to the paraffin soaked rags you've been cleaning with either

Actually not as funny as it sounds..i like to keep my rags all together well away from the bench and sparks area, i remember once locking my workshop up and come the following morning finding a pile of black ash on the bench.....I had been grinding and it ignited a rag but not enough for a fire when i was in there,just a smoulder all night or something could of been bad...