BEWARE On the CMPro p-40 140 size plane that the spinner is made out of plastick and wll exsplode in flight............I have seen this happen on YOUTUBE with the Messersmit BF-109 and started to check my nose cone. Sure enough the same cone that is on the Messursmit is on the P-40 140......The back plate will start to crack and the plastick S NOT FUEL SAFE.!!!!


I love the CMPro product

I just wanted to warn everyone of the issue..,..

I've seen similiar things said of many plastic spinners no matter the manufacturer, however the problem usually is not the spinner...

Though a word of caution: I don't have that particular plane though, so this may not apply to it....

However I've used CMP spinners w/o any problems... on other planes.




Spinners should NEVER contact the prop hub or blades except for a fairly small circle around the prop shaft.

What often happens is that the lip of a plastic spinner backplate contacts the prop.

As the prop nut is tightened the plastic backplate is pressed against by the prop blades, deforming it, causing it to crack and weaken, and resulting in a break or fracture while in operation.

Also I've seen people complain about plastic spinners breaking, when the spinner cone is effectively tightened against the prop blades, or overtightened against the plastic backplate.

If you use a plastic spinner, they are usually safe provided that they are properly affixed, and only are gripped by the prop driver and prop at the prop shaft... that is in a small circular area around the prop shaft...

The prop must never contact the spinner, nor spinner cone elsewhere.

NEVER, EVER use a spinner that has a bent or deformed cone, or backplate, or looks "off" in any way shape or form.

I will never use a spinner with a plastick backplate ever again. The only two plastick back plates I have ever sed BOTH came from CPro and both have exploded. This was not because I don't know how to bolt on a spinner.

I checked the spinner that came off the p-40 and the plastick is brittle and after inspecting the plastick found it to be full of small bubbles let behind after the injection prosess. This im sure has nothing to due with it comeing apart. On the other p-40 I also have has never seen the air yet and was very glad I inspected the spinner before flight. This was found to have several cracks and bubbles on the OUTER edge.
This has never bee bolted to the engine, So instulation is not the cause of this being junk.

I will remember to throw away all the plastick spinners that come with all the CMPro planes that I buy in the future. The planes fly great and Iove the CMPro product. I would like to see them step up and start makeing spinners with aluminum back plates like the other compaies out there.

There is normally nothing inherently wrong with spinners that have plastic backplates.

I've used them in models ranging in size from 1.40 down to small electrics without problems.

Many different companies manufacture them as well.

Bubbles SHOULD NEVER be present, as you've implied, they will indeed weekend the plastic and will likely cause problems.

It sounds like there is a problem that run of them.


That said, some people do use the included CMPro P-51 and the BF109 spinners with success as noted in the Warbirds threads.

Anyone is best off inspecting them and making sure that when installed there is no strain on the spinner.