Do harvesting tools stack?

[Mustang8259]

I've never really had any interest in Tinkering but noticed the other day that there are items like the Overclocked Automated Pick Axe for mining.  Before I bought one i wanted to know if the stack with the regular Sandalwood Pickaxe?  I doubt it very highly cause that would bring harvesting time down to about nothing...  And also being a carpenter I did the Wantai Artisan's quest and got the little tool that adds I think 1% to success chance while crafting and +10 to skill.  Do the TS tools stack with the Tinkered ones? for example does my Nurwin's Sculpting Stylus for a Carpenter stack with the tinkered Woodelf Eye for the Troll Guy?  This I would think might stack but i'm not sure...  Anyone know for sure?

[KerowynnKaotic]

<p>The Tinkered and the Woodworker Harvesting helpers <b>do not</b> stack. </p><p><b>Nor</b> do the lower level of [either] stack with each other. </p><p>The Tinkered Crafting Helpers <b>do</b> stack with TFD reward Helper. </p><p>The Tinkered Crafting Helpers <b>do not</b> stack with each other. </p>