Stuffing Tube Question: 0.187" flex in 1/4"

[Shooter]

Has anyone ran 0.187 flex in 1/4" stuffing tube (no liner)?? There's a bit of slop and I'm worried it won't be supported radially. I've considered a 7/32" tube, but heard horror stories of overheating.

I've also hear horror stories of the stuffing tube "flarring out" at the motor end with 1/4" (too much slop).

Anyone have experience with this? Thanks!

[BakedMopar]

I run that setup no issues. A 3/16" cable in a 7/32" tube is really tight. This is run with a 1521, 48mm prop in a mono that weighs 9+ pounds.

[Shooter]

That's exactly the answer I was looking for. Thanks. Do you get any water in your hull from the gap? I'm assuming the tighter strut bushing fit and the fact that the windings tend to pump the water OUT as opposed to IN should help. Just curious...

[RaceMechaniX]

The size is correct. To prevent leakage you can use a piece of fuel tubing over the motor end, but make sure it is not dragging too much on the shaft. Shrink tubing also works or just keep it greased.

[BakedMopar]

The size is correct. To prevent leakage you can use a piece of fuel tubing over the motor end, but make sure it is not dragging too much on the shaft. Shrink tubing also works or just keep it greased.

I get no water through the stuffing tube without and tubing etc. Just keep you shaft well greased and you should be fine.

[c_michael_72]

It's been reccomended to me to use the same 3/16" flex direct in a 1/4" tube with no liner. This is for a 36" Cat, Leopard 4092 1730kv, 6s. I'm concerned with wear/maintenance as I've always used teflon, which clearly is simple and inexpensive to replace. Will the 1/4" tube last if setup properly? It would suck to have to uninstall a custom glued and bent 1/4" brass stuffing tube on even an anual basis. Do I have this all wrong?

[longballlumber]

Will the 1/4" tube last if setup properly? It would suck to have to uninstall a custom glued and bent 1/4" brass stuffing tube on even an anual basis. Do I have this all wrong?

Yes and Yes

3/16" flex in a 1/4" brass stuffing tube with NO liner will last longer than the life of the boat (assuming you properly grease the cable and often as necessary).

Later,
Mike

[TINY]

Yes and Yes

3/16" flex in a 1/4" brass stuffing tube with NO liner will last longer than the life of the boat (assuming you properly grease the cable and often as necessary).

Later,
Mike

most of my oval are as above... Re grease every race... Teflon is a toy and great for eggs on your frypan..

[longballlumber]

Has anyone ran 0.187 flex in 1/4" stuffing tube (no liner)?? There's a bit of slop and I'm worried it won't be supported radially. I've considered a 7/32" tube, but heard horror stories of overheating.

I've also hear horror stories of the stuffing tube "flarring out" at the motor end with 1/4" (too much slop).

Anyone have experience with this? Thanks!

Hey Pete,

You have the right stuffing tube spec’d out. I am not sure what your putting this in, but I would suggest putting an "S" bend into your stuffing tube rather than the "J" style bend that seems to be more popular in the FE world. The S bend can be slight and is what goes into ALL of my boats. In my mind and opinion; at full song, the flex is trying to straighten out. An S bend is going to support the flex at 2 points. To me that supports the flex better than the J style bend. You've seem my stuff run. The proof is in the pudding...

Another thing to think about is gluing the next size tube into the hull (9/32" brass tubing I think) into the hull and uses that to sleeve the ¼” shaft. That way if the ¼” shaft ever gets damaged you can replace it with out ungluing the 9/32” tube. I have used this method in my P-Limited Sport Hydro (the orange one), my recent Q sport build, and my new .21 rigger. It works!

Later,
Mike

[c_michael_72]

Mike,

Many thanks!

Chris

[Steven Vaccaro]

Another thing to think about is gluing the next size tube into the hull (9/32" brass tubing I think) into the hull and uses that to sleeve the ¼” shaft. That way if the ¼” shaft ever gets damaged you can replace it with out ungluing the 9/32” tube. I have used this method in my P-Limited Sport Hydro (the orange one), my recent Q sport build, and my new .21 rigger. It works!

Later,
Mike

thats the way I do it on my personal boats. Makes changing the stuffing tube easier. I've found with the s bend you will need a shorter 9/32 tube.

[c_michael_72]

A quick search yeilded two similar hardware based alternatives to glassing in a tube.

http://shop.redlinemotors.us/Stuffing-Tube-Block-and-Alignment-Tool-RLPM-STB.htm

http://www.modelgasboats.com/Butch_Block/