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Author Topic: Should the prop shaft be sloppy in its tube?  (Read 6494 times)

flybobby

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Should the prop shaft be sloppy in its tube?
« on: July 19, 2006, 09:00:53 pm »
Hi, I have just noticed that the propshaft is a little sloppy in its tube, is this normal?

It is a new shaft and tube bought from ebay (a guy who makes them himself).

I would have thought it should be a close tolerence, but there is an easy 3mm of play with mine!  ???

Any ideas before I go out and buy a new set!

Thanks  ;)
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GOGSAMWE

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Re: Should the prop shaft be sloppy in its tube?
« Reply #1 on: July 19, 2006, 09:23:06 pm »
FlyBobby,

you are indeed correct, there should'nt be loads of tolerance between shaft and tube...... if there is... I am afraid you will take on water :(

Better to keep the wet stuff on the outside.  ;) trust me

Seems your supplier hasn't supplied a matched pair , perhaps ? ie: shaft is much smaller than the tube ?

See what the other Mayhem peeps have to say


Steve
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Wetwater

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Re: Should the prop shaft be sloppy in its tube?
« Reply #2 on: July 19, 2006, 09:31:51 pm »
Maybe the outer tube end bushes are missing.
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Alan.

BobF

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Re: Should the prop shaft be sloppy in its tube?
« Reply #3 on: July 19, 2006, 10:34:47 pm »
Hi flybobby,

If this is Hanna parts equipment, I have had quite a few of them and all ok.

He does make several types of tube and shaft, but if it is the slim line version, there would not be 3mm play even if the bushes were missing. If this is the company, I would contact him as I have always found him to be quick helpful and efficient.

Bob
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flybobby

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Re: Should the prop shaft be sloppy in its tube?
« Reply #4 on: July 19, 2006, 10:51:36 pm »
I am taking on water too.
Cant say there are any bushes to speak of, what should these look like  ???
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flybobby

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Re: Should the prop shaft be sloppy in its tube?
« Reply #5 on: July 19, 2006, 10:55:14 pm »
Quote from: BobF on July 19, 2006, 10:34:47 pm
Hi flybobby,

If this is Hanna parts equipment, I have had quite a few of them and all ok.

He does make several types of tube and shaft, but if it is the slim line version, there would not be 3mm play even if the bushes were missing. If this is the company, I would contact him as I have always found him to be quick helpful and efficient.

Bob
The guy's ebay handle is monstervan122.  Anyone else purchased prop shafts from this guy?
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Colin Bishop

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Re: Should the prop shaft be sloppy in its tube?
« Reply #6 on: July 19, 2006, 11:03:18 pm »
Quote
Cant say there are any bushes to speak of, what should these look like

There should be an insert at each end of the tube which has a hole exactly matching the diameter of the shaft. The space between the inserts can then be filled with oil to prevent water coming in. Only on the very smallest models should the shaft be a close fit in the tube itself without bushes otherwise you will have considerable frictional losses which will absorb power. To summarise, there should be a hole each end of the tube in which the shaft is a very close fit and the holes should be less than the diameter of the tube itself. if this is not the case then something is wrong.
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BobF

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Re: Should the prop shaft be sloppy in its tube?
« Reply #7 on: July 19, 2006, 11:04:38 pm »
Hi again,

This is not Hanna Parts ebay name

Bob
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flybobby

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Re: Should the prop shaft be sloppy in its tube?
« Reply #8 on: July 20, 2006, 02:39:00 pm »
Quote from: Colin Bishop on July 19, 2006, 11:03:18 pm
Quote
Cant say there are any bushes to speak of, what should these look like

There should be an insert at each end of the tube which has a hole exactly matching the diameter of the shaft. The space between the inserts can then be filled with oil to prevent water coming in. Only on the very smallest models should the shaft be a close fit in the tube itself without bushes otherwise you will have considerable frictional losses which will absorb power. To summarise, there should be a hole each end of the tube in which the shaft is a very close fit and the holes should be less than the diameter of the tube itself. if this is not the case then something is wrong.
Hi, thanks for that, the tube does have this, but the the hole does not match the diameter of the shaft.  This must be why no matter how much I grease up, I am still getting water ingress!  Don't like the idea of loosing power either.  Any recomendations on a supplier of a devent set?  Thanks for your help.  ;)
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flybobby

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Re: Should the prop shaft be sloppy in its tube?
« Reply #9 on: July 20, 2006, 02:51:40 pm »
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Doc

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Re: Should the prop shaft be sloppy in its tube?
« Reply #10 on: July 20, 2006, 06:05:40 pm »
flybobby,
I think the first thing I'd do is contact the seller and see if he will make it right.  From there, you have a number of choices, which I'm sure you already know.
 - 'Doc

PS - If he won't make it right, I think I'd definitely complain to who ever you need to, but then I'm like that...
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Stavros

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Re: Should the prop shaft be sloppy in its tube?
« Reply #11 on: July 20, 2006, 07:47:19 pm »
Had no probs at all with this e bayer,contact him to see what he can do if no jiy wewll it will leave you no option but to report teh guy to tradoing satandards and of course E bay
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flybobby

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Re: Should the prop shaft be sloppy in its tube?
« Reply #12 on: July 20, 2006, 08:47:08 pm »
I have sent him an email, will await reply  ;)
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martno1fan

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Re: Should the prop shaft be sloppy in its tube?
« Reply #13 on: September 18, 2006, 08:50:19 am »
in the meantime make your own prop tube ? buy some brass tube from most diy retailers and get the right diametre for your shaft .you dont need bushes on the shaft at all just get the correct size tube for the shaft and grease her up i finf the ballraced shaft and tubes work better though and they have the grease nipple so you can keep her greases up without removing the shaft.for your boat you might also want to check out the electric power boat sections for a good fast powerfull motor ;)can i ask what length your boat is?http://http://www.offshoreelectrics.com/MainPage.htm check out this site for a good motor look at the stock cen large can motor rated at between 6 and 14 volts that thing will haul your boat at very fast speeds. ;)
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oooo

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Re: Should the prop shaft be sloppy in its tube?
« Reply #14 on: September 18, 2006, 08:23:29 pm »
Dont want to hijack this thread but, should the prop shaft have a small amount of play along it's length. i mean from the motor to the propeller.

Mine seam's to have 1-2 mm of movement, it's well packed with silicon grease and no water gets into the hull.
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Shipmate60

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Re: Should the prop shaft be sloppy in its tube?
« Reply #15 on: September 18, 2006, 09:08:40 pm »
The play along the length of the propshaft will transmit to the motor armature if the coupling is tightly fitted.
I usually fit propshaft to have less than 1mm end play, usually less than 1/2mm, but leave 1mm plus between the coupling and the coupling ends.
This ensures the thrust is transmitter by the propshaft and not the motor armature.

Bob
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cbr900

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Re: Should the prop shaft be sloppy in its tube?
« Reply #16 on: September 20, 2006, 02:55:48 pm »
Also if too tight they can get very hot and cause alot of other problems, and a model on fire is not a pretty sight..


Roy
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OneBladeMissing

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Re: Should the prop shaft be sloppy in its tube?
« Reply #17 on: September 21, 2006, 02:42:26 pm »
Should the prop shaft be sloppy in its tube?
Are we talking about prop shafts here? ..... or is there a problem that needs advice from an agony aunt? Nudge! Nudge!
The "prop shaft" should not be too sloppy nor too tight. Like the baby bears porridge, it should be "just right"!
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martno1fan

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Re: Should the prop shaft be sloppy in its tube?
« Reply #18 on: September 21, 2006, 05:43:00 pm »
you cant beet a snug fit round your shaft!!!!! ;D
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