Tundrahog

Just bought a Octura 670. Have a few questions..??..

1. On trailing edge tip of the prop it's kinda square. It's not symetrical(smooth from toung to trailing edge). There is a nice rake when you look at it on edge. Don't know if this is normal..??.. pic 3



2. There is a bump on the face of the prop....it's not cupped/smooth from the toung to trailing edge. Feels like a bump.?. The drive side has a valley on that side.?. Normal.?. I circled the areas in question. Pic 1 and Pic 2.



Should I waste my time on this prop, or buy a new one from different source. Seems like alot of work and possibly thinning out the prop too much.

Thanks

Having issues uploading pics.....stay tuned.

MrMikeG

Your pics don't show up for me.
Yes it is a bit square, not sure about your bump though.
It is a great mono and cat prop that is easy to work and cheap on the wallet.
I was running one on my Razor on the weekend and it looked very promising, need the GPS tp confirm what I was seeing.

Doubledog

My Feedback: (48)

without seeing the pics its hard to give an educated answer. But knowing how Octuras are with some of the molding, I'd say take a small peice of wet sand paper, put it under a dripping faucet in the yard and rub the face real good. Maybe start with 250 and go to 600 for a few minutes. The wet sanding is to keep the dust down as its not healthy.

Tundrahog

pics added

Doubledog

My Feedback: (48)

Yep, nature of the beast. Run it. Unless you're already about mach2, you shouldn't notice a difference. Try the method I talked about. I'd say a good 20-30 minutes with the wet paper & a dripping faucet will clean them right up. Cut a few small squares of the 250 or 400 grit and a drip of dishwashing soap. Move on to the 600. A shine will start to form and if you decide to go further, try some 1200 with a dab of soap and it'll be like a miror.

danielplace

This is why a ready to run prop is 3 times the cost of a raw casting they are a long ways from done they are a lot of work to get just right.

Best of luck. Most importantly make sure the balance is right.

Tundrahog

I did buy one prop ready to run. P275 SS - $69. Looked like they hit the prop with a wire brush. Put in on my great planes balancer.....yep out of balance. If you want it done right. Learn how to do it and do it yourself.

I don't have an issue working a prop. I think taking out the bump on the face and valley on the drive dog side will thin the prop too much. I will hit the LHS and see if they have on in stock to compare. It's a $20 prop....

Thanks

Tundrahog

Hit the LHS.....they did have a 670. Checked it out....night and day compared to the prop I got online.

I remove alot of material to get the prop(online prop) in balance....not by much. Still didn't like the on line prop..... Decided to get the LHS prop. It was only 20 bucks....no bump on the face and no valley on the dog side. Should have it ready in a week or so. Waiting for a 6717/3 4.84 also. So many choices, so little time.

Boat all apart....add glass/epoxy to stringers, new tank, Tx/Rx and servos, killer bee, tiny tach, volt watch2, move pump, fixed aromarine rudders, clutch bearing, and new cooling lines. Crazy....NO!

painman

John, are you building a BJ55, if so I would think because of the weight you would want to turn a bigger prop, like the 275 or mabe even bigger. It will depend on what motor you will be putting in the boat. All though the 6717 is a good all round prop, it may be the best for the boat. It seems to work on what ever i run mine on, every body needs the 6717/3 can't go wrong.
Sounds like you have a complete rebuild going on, when do you think she will be going back together, keep us posted as I would like to know what prop works best.

Good Luck;

Randy

gtdad

i would go back and look at dockman's posts. he has done some reinforcement upgrades. and he is doing some pretty extensive testing on his bj55 and has tried several props. also, peerpsi has several excelloent posts on the subject. they are running 50+ with theirs........good luck