bebopin64

My Feedback: (2)

ive found that the more i nick and roughen my drive shaft the smoother it is in the stuffing tube. is this because the grease can stick in the shaft more?

TCHedOff

Beboppin,

Out of curiosty...why/how did you start the practice of "nicking & roughening up" your flex shaft?!

Anyhow, your flex cable is made from braided metal strands. Nicking and roughening them up will at the least, make the flexshaft weaker (bad @25000 RPMS - you are asking for to fly apart on you) - and "nicking" is likely resulting your breaking some of these strands.

The reason it seems "smoother" to you is because you are wearing out the factory diameter of the flex shaft (its not fitting as snugly in the stuffing tube as it did when it came from the factory). This "play" you are creating is going to lead to your wearing out both the flex shaft AND the stuffing tube prematurely.

That sound about right everyone?

Ron Olson

My Feedback: (1)

It must be that he has the older straight shaft version. The only thing that I can see is the the nicks are holding the shaft away from the tubing wall ans letting the shaft make only light contact inside there as opposed to the whole shaft.

Canuck Subbuilder

this is still a part of the drive system that confuses me a little bit. do you buy the stuffing tube and the drive shaft (rigid straight or flex) separate and then put them together or is everything complete? if you have to put them together how does that work?.....

Sorry for my ignorance but the hobby shops in land locked Edmonton are all cars and planes and that's fine bit they don't know much about boating so my questions to them have all been answered with a big ol' shoulder shrug and a "look on-line". Not much help because everyone assumes that it's a straight forward concept and maybe it is but i still don't understand how it works.

Ron Olson

My Feedback: (1)

OK, to simplify things. The stuffing box is generally a brass tube sometimes lined with a Teflon tube. I have no idea why they call it a box as it's round. The driveshaft goes through that, wheter it's a solid shaft or a flexible wire cable. Some places you can buy them together or separately. You can buy them assembled with the flex cable and prop shaft already joined, that's my preference as I'm not that hot at soldering not to mention lazy.
I'm more than happy to answer questions by new boaters as long as they're honest. We weren't born boating geniuses and were all where you were at one time. You have to learn somewhere and on the internet is one of the fastest places to get an answer.
Just don't ask me why boats don't have air filters, that one sets me off.

piper_chuck

My Feedback: (12)

But why do they call them air filters? Aren't they supposed to filter out the dirt? Shouldn't they be called dirt filters?

Umi_Ryuzuki

A "Stuffing Box" is actually a four sided box built on the bottom of the hull around where the shaft exits. The shaft passes through the front of the box, down through the center, and out the bottom of the hull. The box is then stuffed with grease, and then a lid is placed, or cemented on top.

I helped "Beboppin" with a stuffing tube here.
A couple of pictures, an explanation, and a quick drawing on an envelope.

http://www.rcuniverse.com/forum/m_3149398/tm.htm

His prop shaft may turn better after being nicked up(sanded), because the shaft is cleaner, slightly thinner with more clearance, and the scratches may allow grease to enter and lubricate the bearing.

Canuck Subbuilder

Alrighty, i thinks I pretty much get it now.... thanks for the step by step link Umi.....

now the bearing of which you speak... all it is is the driveshaft being really snug to the inner (now somewhat tapered) wall trapping the grease in on both sides; and the friction caused by the rubbing of the drive shaft against the bearing is creating the scratching which is letting a little grease through to lubricate? this thing seems so simple in concept but complicated when you get to the details of it.

thanks for the tutor lesson....

how much do I owe you??????????

DONS BOAT WORKS

My Feedback: (3)

Ron,
I use to have a 17 foot Chris Craft I would pack the stuffing box with a grease impregnated rope.

Stuffing Box Maintenance and adjustment or re-packing of prop shaft "stuffing boxes" (aka "packing glands" or "propshaft glands").

bebopin64

My Feedback: (2)

i have a strait 3/16 steel shaft and ive found it moves a lot better if i put nicks in it because it holds grease a lot better, and also it is slightly smaller so it is not as tight in the stuffing tube. it makes sense (how do you spell that?) if you think about it but at first it seemed to go against reason as a not smooth driveshaft should have more friction.