Stinger size for MAC67 pipe

[Ian Inverarity]

I am playing with pipe designs for a MAC67 running 50% nitro, I tried a 0.39" stinger, but that was too small. Was thinking of trying 0.45", any one else played with stinger sizes on this engine? :blink:

Nitrocrazed racing: One lap wonder.

 

[gil sonsino]

0.45 works well on my rigger using the same engine but 60% nitro.Pipe is a Mac nitro 15cc.

Gill

 

[Ian Inverarity]

Thanks Gil! B)

Ian.

 

[EatMyShortsRacing]

I got a stock MACS 67 Muffled (2 taper) pipe on mine and it seems to come on hard.... Will try choking it down a little though...

 

[Ian Inverarity]

Craig,

I guess if your pipe is muffled you cant actually measure the stinger diameter?! :huh: I would be interested if you can tho!

I am playing with one of those funny carbon pipes at the moment. So far it is interesting! My bird is much better as a 67 boat now! B)

Nitrocrazed racing: Box stock=still fits in the box.

 

[EatMyShortsRacing]

got a pipe cutter.... I'll tell you the stinger diameter

yes well my bird had a lil accident over the weekend..... went over and managed to take a chunk of rudder courtesy of the prop.... (read prob now has hole in it..)

Had a JR Digital servo on it and the rudder managed to bend around to hit the prop..... this a 'feature' of digital servos????

EMS Racing More experience... more broken parts...

 

[Ian Inverarity]

Craig,

Are you actually practicing with your boats?

Sure I got a pipe cutter!

Ah, you found the problem with cart-wheeling with a rudder next to the prop! WHat happened is the back end of your boat slapped the water sideways as the boat tumbled and the rudder got pushed into the prop with enough force to over-ride your servo! I have had this a couple of times, bent the rudder pushrod, tore the linkage off the arm, broke the servo arm once.... :huh: Now I have collars on the linkage in the rear-most compartment that act as mechanical travel limiters!

And people asked me why I had such a long rudder bracket on mine! All the better to keep the rudder out of the prop.... B)

What servo do you use? Mine is a DS8411 in both big riggers.

Nitrocrazed racing: Too much experience lately....

 

[shoboat]

Craig,

I hope your not tearing up those nice H-32's that I did for you.

You may want to extend that rudder back a little more like Ian did.

Another way is to put a longer strut on the boat,this will help the boat

handle your rough water a little better also. It makes the boat a little

longer.

Good Luck,

Mark Sholund

 

[AndyBrown]

A .450" stinger bore is a good all a round size for the MAC 67. .430" could be better in cool/cold weather. .410" for really cold weather.

 

[Ian Inverarity]

Thanks Andy, 0.45 it is! B)

Ian.

 

[EatMyShortsRacing]

Craig,
I hope your not tearing up those nice H-32's that I did for you.

You may want to extend that rudder back a little more like Ian did.

Another way is to put a longer strut on the boat,this will help the boat

handle your rough water a little better also. It makes the boat a little

longer.

Good Luck,

Mark Sholund

Mark,

Yes it was the middle one of the three it has taken a chunk out of. Does not look like the blade is bent but I think a lil rebalancing may be needed. Will have to talk soon about the next order. I think I will go with the extended strut as I have a few other little ideas as well that will suit a longer strut.

Ian,

Fancy that.... running boats outside race day!!!!

EMS Racing 8 model memory is just not enough!!!

 

[TimD]

Craig,

If you are getting more in from Mark - LMK. I need one or two also.

Mark,

Rogers boats were hauling this weekend! Mine was fast but inconsistent. Too many DNF's due to unrelated stuff.

Tim.