Rob I have never not had it fix the bait. They always swim perfect afterwards. Here are the keys to success.
#1 you have to boil it long enough to get straight. If its not striaght when you take it out of the boiling water than you didnt boil it long enough. PUT IT BACK IN!.The plastisol will naturaly revert back to its original shape. This might take a few minutes. When I biol up a big batch of saltwater baits that sat in my box for 6 months I might let them sit in there for 10-15 minutes. They get all cloudy looking. One bait wont take that long but I was just giving an example. Also just because the tail looks straight doesnt mean the rest of the body is straight. It could be arched, thats why you boil the whole bait except the eyes.
#2 once the bait is heated up and straight it will keep what ever form/possition you leave it in. If its my gills I just throw them in a sink full of cold water because they situpright and will cure perfectly straigh. I also do this with the saltwater baits because they are small. A bigger bait like a Hudd I would hang. Remember they will stay in that cured possition.
The only thing that boiling wont fix is crease marks. It will help but it wont illiminate them. I am referring to when your bait jets caught in the lid of your box and has the indention from the lid.
I will tell you what Rob, send me the crookedest bait you got and I will srtaighten it and it will run tru as long as bait poured correctly, meaning the harness inside is straight.
#3 boiling will straighten ALL soft baits with the exception of salted impregnated baits. It will straighten them but it will disolve all the salt. You can also alter or customize baits when they are still warm. You can stretch them if your carfull or change the angle of the tails,etc.
So far every customer that did as I instructed them later informed me that The baits ran true and perfect just as I said they would.
My guess is you didnt boil them long enough.

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