DF Sniper 45 T-Mono Build Target 100mph

[RaceMechaniX]

For the larger diameter I went here: www.carbonfibertubeshop.com

They have a remnents page of off lengths and "B" grade finishes. I picked up some 1.125" OD carbon tube 24" long for about $47

http://www.carbonfibertubeshop.com/more%20tubing.html

Some good deals.

Tyler

[Make-a-Wake]

Any news? I've been itchin' to see this baby run!

[Boaterguy]

Me too, I want to follow this, let her take a drink, she's thirsty!!!

[RaceMechaniX]

Guys,

She only had one short run at the Legg Lake SAW's. The first and only pass looked awfully hot as she ramped up. At 3/4 throttle the boat accelerated like a banshee and shortly thereafter took flight before I could get out of the throttle. I would estimate low 80's when she got loose. No second pass was made due to the Schulze shorting on connection to a new set of batteries. The combo showed a lot of promise for speed, but I need to do some tesiting prior to a SAW event to find the right balance between prop, current and attitude. I will keep the thread updated when I get the controlled back and installed.

Tyler

[Make-a-Wake]

Sorry about your mishap...................i just knew this thing would scream and was looking forward to a vid one day...............thanks for the update!

[rearwheelin]

Consider inline rudder , it will help the bow stay down but will add drag from prop wash. Was an inline set up that took Q offshore !..........

[RaceMechaniX]

For my tastes, I do not like inline rudder set-ups. The drag from the prop wash can be signifigant and IMO its better to have the rudder in clean water for control. I just need to adjust the tabs and CG a little and test, test, test before the event not on the day off.

Tyler

[rearwheelin]

For my tastes, I do not like inline rudder set-ups. The drag from the prop wash can be signifigant and IMO its better to have the rudder in clean water for control. I just need to adjust the tabs and CG a little and test, test, test before the event not on the day off.

Tyler

True ! Inline is good for certain apps and not all. Wish you the best and nice build..

[RaceMechaniX]

Thanks Rearwheelin, I will get her out testing with more conservative props and set-up before too long. I am traveling a lot for work recently so it may not be till after the Nats at Legg Lake that I have a chance to run her again.

Tyler

[Jesse J]

Nice thread! Any news ? Maybe sOme video?

Curious to know your thoughts on what you might have done differently?
I am about to start an XXX build and will be doing the flooded stuffing tube as well - not going for 100mph more like adjistability.

Hope all is well
Jesse

[RaceMechaniX]

No major news to report. I brought the Sniper to the nitro/gas NAMBA nationals and changed the 3080/5 to a Wye wind which makes it a 600kV motor. I did a quick run with a X467 and the mono only ran 62 mph. This would have been fine for the open offshore class if they would ave kept the short layout, but we changed to the longer layout so I ran my gas mono instead. I have since switched to a 3080/6 which should be a good middle ground between the 1020kV 5 wind and the 600kV 9 wind. We have a SAW event coming up in August where I will run this mono and several others.

I pretty much liked everything on this build. The only tight spot was installing the steering servo. The XXX I believe has more room to work with. I would reinforce that hull with 2 layers of glass or carbon especially around the seems to stengthen it up.

Tyler

[RaceMechaniX]

A little follow up to this thread.

Although I did not meet the 100 mph target I was able to set a new NAMBA S mono record at 76.76 mph at Legg Lake on October 16. This was running on 8S2P Hyperion 45c packs with the 40.303wk and a Lehner 3080/6 spinning a X572 that has been cupped slightly. Logged data showed sustained current draw through the lights around 450A with the battery voltage hovering around 28V. 450Ax28V=12,600W! Here is the 8S record pass:http://youtu.be/2QCDRwweq1w

Tyler

[Steven Vaccaro]

Nice build and record. Will you be trying to up that record in the near future?

[RaceMechaniX]

Yes, but with a different set-up. Going to try the lighterweight set-up in a smaller hull turning more RPM's.

Tyler

[Punisher 67]

Nice write up Tyler

What prop were you using to go the 76mph , I am pretty sure you had it tweeked I am just curious what kind of MM it started out as .

[RaceMechaniX]

Peter,

It was an Octura X572 will a little cup added and almost full diameter.

Tyker

[Doug Smock]

Wow 450 amps and 76 mph. Was she running wet or just that heavy?

Congrats on the record!
Doug

[properchopper]

Here's the boat from a year ago carving the buoys (and looking fine) on 8S :

http://www.youtube.com/watch?v=m5pd683KmRE

[T.S.Davis]

Nice to see a boat built that can take a stuff at that speed if it happens. Really nice build.

[RaceMechaniX]

Wow 450 amps and 76 mph. Was she running wet or just that heavy?

Congrats on the record!
Doug

Thanks Doug, she is just that heavy somewhere around 25lbs RTR. The boat runs pretty wet on 8S and I only got to run 10S once. On that run(the first maiden run in SAW trim) the sniper looked and sounded like it was going to break the sound barrier on the run up right before it flipped. The amperage was through the roof!


Tony,

That video is of the AM conquest cat. Close, but you can see the blue bottom on the cat as it goes around.

TG

[Make-a-Wake]

Hey Tyler, I notice your rudder setback is quite far................what is the measurement of your setback, and does it help in cornering, seems like it would............Thanks!

[RaceMechaniX]

It is a 6" setback for the rudder. It was mounted deep to aid in turning and stability when planning on the ride pad and prop.

[SlickZERO]

The idea behind the flooded stuffing tube is to allow vertical moving of the strut. If you just had the stuffing tube pass through the transom and it was a tight fit so it sealed the water then it would be impossible to allow for any strut adjustment. In nitro and gas boats we just make an oval hole in the back and leave it open for water to drain out. In the FE boats, we have to seal it, so we install a larger tube which the stuffing tube fits in. We epoxy the tube in the rear on the OD to seal the tube to the transom. In the front of the tube, we seal the stuffing tube to the ID of the big tube. Now we have a sealed tube, but with th extra length between where the stuffing tube is sealed and where we have the strut we have enough bend allowance in the stuffing tube to make strut adjustments. The stuffing tube is supported near the motor by the expoxy and its supported at the rear by the strut.

Hopefully that all makes sense.

It does. Thanks for taking the time to explain. The pictures helped too. Now I get it.