Boring a Prop ID

[sanjayrai55]

Having recently got into Electrics, I face a problem with Props.

e.g. I have a prop adapter that is 8 mm. The max bore of the props are 6 mm, sometimes 1/4" (6.35 mm)

The problem is how to increase the bore without imbalancing the prop? I mean, it is easy to run an 8 mm drill through the bore, but chances are high it will imbalance the prop.

Any suggestions anyone?

Thanks

[sanjayrai55]

BTW, never faced this problem with Nitro engines. The maximum has been slight reaming.

[rcpilotacro]

Sanjay
Step Reamer is the best i found, you could even drill with the same dia bit (Ensure 90 to plane of rotation)

[sanjayrai55]

Gusty, a fixed stepped reamer will not cut from 6 mm to 8. With a drill bit, there are chances it will not be concentric to the original hole, thus the imbalance. It is possible that at the RPMs we work with (read a 1200 KV motor on 11.1 V = 13320 RPM) even 20 micron eccentricity could lead to imbalance, I think. Don't have experience of this,and I have drilled it, let's see what happens!

[sanjayrai55]

OK! An update. I did this in two stages, and I did not use a drill machine, but clamped the drill in a vice, and "threaded" the prop up and down it. Shot in the dark really, but seems to have worked...no vibrations at full RPM