sealing card sleeves

Wait, for future use for others, does it turn out that you can seal card sleeves with a heat bag sealer?

I am using a plastic bag sealer and I use a needle to release the air. But now that I think about it, I have a problem with my new sealer. ( Sorry, for using somebody else's thread to post my problem).

The problem is that my sealer has 2 heat strings. The second heat string (that does not cut) is under a strip of white tape with texture. Consequence, it makes ripples on the plastic before the cut.

In an attempt to solve the problem, I have stuck some card board on the second string to isolate the plastic sleeve from the heat. But now the card is higher than the cutting string and it pull down the plastic when I cut it. So the length of the top portion of the sleeve is higher than the bottom portion. Which makes some kind of ripples when I flatten the sleeve. ( Yes, it is hard to visualise )

First, can you think any other method to solve this problem?

Else, for those who knows a lot about electricity, I intend to modify my sealer. The solution would be to cut the 2nd heat string but, I am not sure if the string are wired has on a serial or parallel circuit. If it is serial, I am doomed, if it is parallel, I might be OK.

But then again, there might be some other dangerous consequences, that I am not awared by doing such a thing. Maybe, I can cut the wire and place and high level resistance to make sure the current pass, but the string does not heat. Or replace the string with a low resistance string to make sure it does not heat up.

Damn!, why did it had to have 2 strings, it's a totally useless feature. My grand mother's 1 string sealer was working perfectly even if it was an old one!