I have the Klein Tools Journeyman Crimping/Cutting Tool (J1005) which is sold at Home Depot. You can also get it online at a bunch of places, including Amazon.
It works very well. Not sure what price range you're looking at but this is around $35.
As for technique, just line the uninsulated crimp up in the center of the spade & give it everything you have. I've done hundreds of crimps & not one failure. I'm guessing you have split style barrels, so gently squeeze with the insulated crimp just enough to hold the wire snug before nailing it down. Of course, put the pointy part of the crimper on the solid portion of the spade. If you need pics, I'm doing a set now & can send them to you.
It works very well. Not sure what price range you're looking at but this is around $35.
As for technique, just line the uninsulated crimp up in the center of the spade & give it everything you have. I've done hundreds of crimps & not one failure. I'm guessing you have split style barrels, so gently squeeze with the insulated crimp just enough to hold the wire snug before nailing it down. Of course, put the pointy part of the crimper on the solid portion of the spade. If you need pics, I'm doing a set now & can send them to you.