If you are like many eco players you have several steel companies producing steel for your next upgrades and have only crafted and dismatled gear for the daily quests.
This is a very easy way to get a LOT of xp with the new update using milestones.
Step 1: buy a stockpile of scrap with whatever cash you have on hand (you'll get the cash back at the end!)
Step 2: craft as much random common gear as you can
Step 3: scrap all the common gear (keep max stats gear if you like)
Step 4: repeat step 2 and 3 until you have no more steel.
Step 5: sell your stockpile of scrap to get your original investment back (may be a very slight loss due to tax)
Go to your milestone tab. You should now be able to rank up multiple levels for crafting and dismantling items. This gives a massive 100xp per rank.
I did this and gained a couple of levels from just these two milestones.
Enjoy