Makerbot 2 issue

I just got a used makerbot 2. Its my 4th printer but first makerbot. It has an issue where it extrudes fine when loading filament etc. It prints an absolutely perfect raft. But then in the first few layers of the actual part it stops extruding. When i pull the filament out i see the divot where the extruder teeth ground into the filament. So i went through all the unclogging procedures including running a .3mm wire through the nozzle. Im certain there is no partial clog. I tried 3 different filaments including some brand new makerbot filament i bought today. It also appears that if you physically hold the filament it continues to print. I took apart the extruder assembly completely and cleaned it up. Everything looks in good order and it has the upgraded spring extruder as well. Does anyone have any ideas?

Thanks,
Zach

I don't think that the "upgraded" extruder is much of an upgrade personally. It seems to give this type of problem a lot.

Not a lot you can do, new nozzle, stretch the spring, that's about it.

I am assuming you have tried different filament already.

Yep brand new filament and 2 older brands.

Have tried printing a different model?

I have had a similar problem when printing a model with very small parts. If the amount of plastic flow got too small, it would stop extruding.

Odd that there is also another thread in this forum about raft collision issues.
I try not to use rafts and instead use a helper disk that is scaled to become a raft. This allows me to float the model above the print bed for easier cleanup. Works great for most items but now I am now having trouble printing thin walls for model parts.