4mm thread pitch

[MadProps]

Gentlemen
I dont have a metric thread gauge handy anyone know off hand what is the thread pitch used on the 4mm bolts, nuts, prop shafts etc etc in our hobby

I need to make my own outboard flex shafts and need to buy a die to match the existing 4mm prop shaft ends, I need to run a die a little farther down the shaft and Im golden

thanks for looking

[rol243]

standard thread pitch for the 4mm bolt thread is 0.70.

[properchopper]

get a 4mm x .70 die. Eat a big breakfast - those shafts are hard

Did a little detectiving to confirm my remembrance :


From the OSE prop nut listings :

Product ID mc-94150a335
Nut : Stainless : 4mm
In Stock 172

4mm Stainless steel nut.

(1) per pack

These work well as a propeller nut on 4mm threaded .7 pitch shafts.

Material: 316 Stainless Steel
7mm width x 3.2mm height

[MadProps]

thanks guys

[MadProps]

a thought just came to mind....flex cables soldered into the prop shafts can be taken apart with heat if the flexy breaks

Ive never used 648.....can loctite 648 be taken apart with a torch? its heat resistant, or are the loctite prop shafts finished when they twist a flexy

thanks for looking

[properchopper]

For Disassembly:

1. Apply localized heat to the assembly to approximately
250 °C. Disassemble while hot. [250C = 458F]
For Cleanup
1. Cured product can be removed with a combination of
soaking in a Loctite solvent and mechanical abrasion
such as a wire brush.

[rol243]

Speaking of Flex Shafts. out of 2 x CC Racing brand 3/16 flex shafts both are slightly out of true. i don,t know how these guys line up there 2 parts for soldering but something aint right.

[MadProps]

thanks again properchopper

I bought 2 HobbyKing 650ep CNC'd lower unit outboards and the shafts are a disgrace, first one broke just testing to see if there was power to the motor with 3s, second shaft broke 45 seconds into the run, 3rd shaft broke 2 min into the run and I realized these are garbage like the HobbyKing Hornet F1 flex shafts that also break ALMOST as bad
but at least twin motors always get you home!

so I made my own flex shafts with OSE bulk shaft bits and tried to break them today I wanted to see how much prop I could run, they were a vast improvement, today the shafts ran from 30mm to 38mm props on 3s and 30mm to 38mm props on 4s

but the 38mm on 4s was just too much blade....and stretched the shafts but at least they didnt break and I can run 4s for sure as intended, once I propped it back down

I also upgraded one of the motors to a leopard 2860 and it twists the shafts more frequently, so the torque and rpm increase is evident with a leopard motor upgrade

so bottom line review I really like the motors for their appearance mostly, Im merc guy, they have 2 roller bearing in the lower unit, but the flex shafts are crap like most HobbyKing boat parts so be prepared to upgrade the shaft and liners out of the box
as to the stock motor.... longevity seems to be hobbykings motor short comings with my experience and I cant really say, I will be upgrading the stock motor I didnt do to match that better performing Leopard 2860 tomorrow so the motors match
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