Cutting issues with sp300

[deep six]

My SP 300 has been giving me hours of grief lately with poor cuts.
Sometimes it works OK and other times it is almost impossible to weed out the vinyl.
It just doesn't cut deep enough, I have replaced the blade several times but just doesn't seem to help. Have upped the cutting pressure but for some reason my machine doesn't seem to hold the new setting, I can set in on 80 and it will stay that way for a few cuts then revert back to 50.
Has anyone had a problem like this, could it be the solonoid that holds pressure on the blade is getting weak and needs replacing.
I probably should mention I am using oracal 551 vinyl with a clear lamination over the top.
Any tips greatly appreciated.

Cheers

 

[Speedsterbeast]

Have you tried adjusting the depth of the blade manually with the thumbscrew?

 

[w2csa]

It could be the blade holder. The little bearing could be worn out.

 

[deep six]

Hi Guys

Thanks for your thoughts, I did try dropping the blade down lower but didn't seem to make much difference, however will try it again and see if it helps.
Will check the bearing thing too.
Many thanks

 

[asd]

have you checked your cutting strip?
mine wasn't cutting smooth of finishing the cuts once I replace that, problem went away