Model Boat Mayhem

Mess Deck: General Section => Model Boating => Topic started by: GAS on August 26, 2011, 09:41:18 pm

Title: Prop shaft assembly help.
Post by: GAS on August 26, 2011, 09:41:18 pm: Well this weekend i'll be installing some hardware in my speedboat and I need a little help with the prop shaft assembly.

I've bought a 10" JP stainless steel one but am a bit unsure on the following?

Firstly, the two threaded ends one is very slightly tapered and the other not which is also slightly shorter than the tapered thread. Which ends should the coupling / prop be threaded?

Both ends have a washer and nut. should the washer and nut be tightened against the coupling and prop or against the end of the tube?

Hope that makes some kind of sense!!!

Thanks in advance.
Title: Re: Prop shaft assembly help.
Post by: DickyD on August 26, 2011, 10:10:22 pm: Tapered end goes in prop.

Washers and nuts go against the coupling and prop and act as locknuts..

Make sure you leave a little slack when fixing prop shaft in tube so shaft doesn't bind.

Hope this is helpful. :-))
Title: Re: Prop shaft assembly help.
Post by: CGAux26 on August 27, 2011, 12:56:42 am: Here is a similar tread from RCGroups. Enjoy.
Dave

http://www.rcgroups.com/forums/showthread.php?t=1495008
Title: Re: Prop shaft assembly help.
Post by: GAS on August 27, 2011, 08:02:59 am: Thanks for your replies so far.

Am i correct with the setup below then?

Right to left = Prop - Washer - Nut (Tighten nut against prop).

(http://i1193.photobucket.com/albums/aa358/GASdesigns/IMAG0089.jpg)

Left to right = Coupling - Washer - Nut (Tighten nut against coupling).

(http://i1193.photobucket.com/albums/aa358/GASdesigns/IMAG0087.jpg)

Thanks.
Title: Re: Prop shaft assembly help.
Post by: DickyD on August 27, 2011, 08:40:47 am: Washers need to go other side of nuts to prevent wear on prop and coupling. :-))
Title: Re: Prop shaft assembly help.
Post by: MikeA on August 27, 2011, 08:46:44 am: what motor you running gas? i got my hardware in this weekend :-)) just needs painting now
Title: Re: Prop shaft assembly help.
Post by: treeboa on August 27, 2011, 09:04:06 am: there is far to much free play on that shaft, max should be the width of the washer
Title: Re: Prop shaft assembly help.
Post by: Timo2 on August 27, 2011, 09:07:02 am: Hi all

  My Twopence worth the order of fitting is

   Shaft , Washer , Nut ( to be used as lock nut on to Prop. ) Prop. A small bit of "Thread Lock2 can be used on the prop threads"

   Prop Fitted OK , :-)
   Motor end Fitting , Shaft in Prop tube ( with tube lubed up ) Fitting order , Washer , Nut , ( to lock on Coupling )

   Tighten nut down shaft with fingers till firm , slacken back to give some end float ( play in shaft .5mm / 20 Thou ) . Holding nut fit coupling .

   Job dun :-))

   Timo2
P.S.

You adjust shaft end float if to much by adding 1or2 washer at motor end
Title: Re: Prop shaft assembly help.
Post by: GAS on August 27, 2011, 10:01:20 am: And what's the best type of grease to use?
Title: Re: Prop shaft assembly help.
Post by: DickyD on August 27, 2011, 10:35:19 am: You are going to wish you hadn't asked that.

I use Heavy Duty Marine Propshaft Grease http://www.cornwallmodelboats.co.uk/acatalog/prop_shaft_accessories.html

Looks exspesive but you dont need much.

I still have some in my tube and I have been running up to eighteen boats for five years on what I have used. :-))
Title: Re: Prop shaft assembly help.
Post by: treeboa on August 27, 2011, 10:47:26 am: Plumbers silicone grease in mine at moment
Title: Re: Prop shaft assembly help.
Post by: HS93 (RIP) on August 27, 2011, 11:25:51 am: No 1 you need enough washers between the prop nut and shaft so there is no thread touching the bearing as it wont do it much good
No 2 I would put a oiler in and use oil as it is one of the narrower shafts which have only a small gap between the shaft and inside of the tubs so will cause drag I use a small amount of 3 in 1 as your boat has a high speed prop you will not want to loose Power.

but as Dicky D says it is up to you to chose as this has been argued about on hear what seems like hundreds of times, the test is to try with an amp meter then fill with grease and try and look at the difference then make your mind up.

Peter
Title: Re: Prop shaft assembly help.
Post by: GAS on August 27, 2011, 06:30:32 pm: Quote from: Mad_Mike on August 27, 2011, 08:46:44 am
what motor you running gas? i got my hardware in this weekend :-)) just needs painting now

I'm going to be running a tuned 540 with 7.2v. Has worked reasonably well in the past.
Title: Re: Prop shaft assembly help.
Post by: MikeA on August 27, 2011, 10:25:19 pm: is this going to be surface drive or submerged drive? ive seen a couple of those tuned 540 on ebay. theres some really fast 30k rpm ones aswell i think i use one in my next boat.