RCTimer 10x38 props and DJI 2212 motors

[UgashikBob]

I ordered the RCtimer 10x38 props and a Great Plains prop reamer thinking I could ream the props from 6mm to 8 mm to fit the DJI2212 motors on my F550. There are no tapered shoulders on the transition points of the 7,8,10 and 12mm sizes of my prop reamers. I am in a remote area with no precision drilling equipment and am reluctant to drill the hole to approximately 8mm then finish with the reamer. Any suggestions.

 

[UgashikBob]

I have found other threads mentioning that some of the reamers have problems enlarging the holes because the transition points at the four steps of the reamer are not machined well enough to enlarge the hole. I have only tried this by hand and am reluctant to use a power drill because of loss of accuracy. Can anyone recommend a specific brand of reamer that allows you to enlarage the hub hole on cf props? Also once you achieve the desired size are there any slippage problems because of the two flat spots on the dji output shaft.

 

[bnt276]

Probably better to use a drill bit that is just a little larger. It is cleaner than the reamer.
Best to put it on a press to keep level as to not drill off center but I have done it by hand and got good results.

The reamer will fit better after the drill

 

[UgashikBob]

Will give it a try. Thanks for the advice.
Bob

 

[gtranquilla]

Get a tapered reamer from you local hardware store or machine shop...... use it first then switch over to the stepped reamer.

I have found other threads mentioning that some of the reamers have problems enlarging the holes because the transition points at the four steps of the reamer are not machined well enough to enlarge the hole. I have only tried this by hand and am reluctant to use a power drill because of loss of accuracy. Can anyone recommend a specific brand of reamer that allows you to enlarage the hub hole on cf props? Also once you achieve the desired size are there any slippage problems because of the two flat spots on the dji output shaft.

 

[TAPPEDOUT]

I have a reamer that worked very well and maintained a true bore. I think is Great Planes brand marked GPM on it and 7-12mm.
It does have a chamfered flute at each transition. Yes I used drill bits before I purchased reamer and will work, but not as accurate depending on how much the bore needs enlarged. If you reduce to rake on the drill bit so not as positive, it won't try to pull its way through nearly as much. I'm a Machinist and liked the reamer best!

 

[gtranquilla]

The machinists are the experts at this sort of thing. Unless the drill bit is modified it will pull the enlarged hole off from the original center. A pointed tapered reamer enables the fluted end of the stepped reamer to get a start. The other thing to keep in mind is the keep the reamer perpendicular to the prop at all times and to start the reaming from both sides of the prop as a precaution especially if the reamer used used by hand.

 

[Olemil]

Sorry to butt in but I have a question too on reaming props. I have a couple sets of Graupner 9x5 props on the way and need to ream them to 8mm. I also ordered a Great Plains reamer to hopefully do the job. Been thinking of either pre-reaming the holes with a drill bit smaller than 8mm and finishing with the reamer. Also wondering if it would work better to start the reaming with something like this, I have one of these also. PS, I do have a small drill press too but not sure if I want to try using power for fear of the drill bit grabbing and messing things up. Thanks for any help, much appreciated.

 

[TAPPEDOUT]

I believe the reamer I have is Great Planes and it worked fine. It maintained concentricity because first part of reamer will fit existing bore and pilot the reamer. A drill bit can mess things up, especially if point not reground to make it less aggressive. I balanced the props afterwards on a Dubro Prop Balancer. I use the GemFan Black Carbon Blades on my F-450. While the GP Reamer I have is great, who knows if the manufacture of them is always the same. Mine does have a chamfer and a little lead at transitions and worked very well. Really, almost impossible to mess things up. I have been in the machinist trade since 1978.

 

[Olemil]

I believe the reamer I have is Great Planes and it worked fine. It maintained concentricity because first part of reamer will fit existing bore and pilot the reamer. A drill bit can mess things up, especially if point not reground to make it less aggressive. I balanced the props afterwards on a Dubro Prop Balancer. I use the GemFan Black Carbon Blades on my F-450. While the GP Reamer I have is great, who knows if the manufacture of them is always the same. Mine does have a chamfer and a little lead at transitions and worked very well. Really, almost impossible to mess things up. I have been in the machinist trade since 1978.

I'm thinking I'll just try the reamer since it has the leading chamfers on it also. I use 7.9mm three flute drills in my machining centers at work which might be less aggressive, but going to do reamer only first. Shouldn't be too bad no more stock that needs to be reamed out plus I ordered an extra set of props just in case I have a boo boo.....lol. Know what you mean about being a machinist, been there also since 6/77. Too bad we didn't get paid for being in this hobby, much more fun!!! Thanks for the info, hopefully I'll have my props and reamer by the weekend so I can play. PS, like your avatar, ,must be into astronomy also?