Heh! That's exactly what I thought when I read the post too.

To the OP (Ken): Whatever engine it is, the carb's midrange sounds like it's not correctly calibrated - quite common with Chinese engines unfortunately and there's no practical remedy without re-engineering the carb. An OS Type F plug is the best for staying lit in adverse conditions like this. If the F is not staying alight, a glowplug change is not going to solve it no matter what brand you try. I know you've adjusted the engine's needles correctly from reading your post, so it's not an operator issue, despite some suggestions to the contrary.

Try a new carb of another brand or better still, bolt an OS 1.60 FX into the model and be done with engine problems forever.