I just purchased a new AP .061 Wasp engine. The newer engines no longer have the prop bolt and such and now have a typical prop shaft with a spinner on the end. The manual calls for APC props to be used for break in and so on. I purchased the recomended APC prop but the props center hole is too large for the AP engine shaft. Is this due to AP switching to a spinner instead of the typical prop bolt? Has anyone else had a problem like this? Please let me know if there is a solution out there for me. Thanks. Chris

I would just go with a Master Airscrew 6x3 1/2A prop. I have a norvel 061 and it runs very well with it.

APC props give more thrust at the upper range of the RPMs. Master Airscrew props give more thrust at the lower to mid range of RPMs.

You can make a bushing out of a piece of tubing. This is necessary with the APC props on most 1/2A (more or less) size engines.