29" Skunk Works Vee

[Chop]

I am working on a Skunk Works 29” Vee.

I bought a package a few months ago and am just getting around to putting it together. Unfortunately, this is turning into a full on build.

I have a few questions…

The motor mount broke loose during shipping so that has to be re-attached (those USPS guy’s must have been playing soccer with the box to have broken it loose!).

When I pulled the motor out (mount & all). I noticed some play between the rails and the rest of the mount. I tried to tighten it but the holes seem stripped. I can epoxy the two pieces together and be done with it or do it right and make a new piece. Question is, should I have it made from (soft) aluminum and risk stripping the holes again, or have it made from stainless steel? There is a slight chance of corrosion from dissimilar metals touching (the aluminum & S.S.), but I don’t run in salt water so it shouldn’t be too much of an issue.

The electrical setup is as follows:
KB36 11XL Motor
Castle Creations Hydra 240 speed control
and,
Elite 4S 4500 30c lipo’s (2 of them) to power it.

As I was working on it tonight I saw something written on the ESC, it said “20C/6SL.” Does the 20C refer to the max. “C” rating the ESC can handle? Note that I bought 30c lipo’s. I cannot find anything in the instructions that addresses the maximum “C” rating that the ESC can handle.

As long as I’m talking about the electrical part of it I might mention that the male bullets on the motor seem to be 4mm. They might be 3.5, but I measured them when they were not compressed. Will these be enough to handle the amps running through it (it has a 47mm 3-blade prop)?

The local hobby shop could not get 5.5 bullets but had some that were 6.5mm so I got those instead. I was planning on using them between the ESC and the batteries, and putting together a parallel harness to add run time if needed.

The ESC does not look waterproof at all. Should I pull the shrink tube off the ESC and spray it with insulating lacquer or spray on electrical tape? I do not want to cover the L.E.D. that confirms the ESC settings so that might be a problem. Where is it located? I could mask it and pull the tape off after I am done waterproofing it.

Let me know your thoughts.

[Raydee]

The 20c on the ESC stands for 20 cells NiMH or 6 cells Lipo. As far as coating the ESC, I never bother doing that I just keep the ESC off the bottom of the boat whenever possible and make sure the boat is water tight.

[boobmcgee]

that looks nice

[Mich. Maniac]

Very cool, I am gonna watch this one close as I am about to aquire one of these hulls in the next week. I hope it will replace my sv hull. I would think these should handle the wakes of other boats the same and perhaps have a bit higher speeds. Good luck with the build, wish I had some suggestions but I dont have a clue, just learning. Do you know what hardware that is, looks like a perfect fit? I was perhaps going to use sv rudder adjustable tabs and speedmaster strut. please let us know.

[Chop]

I received the hardware when I bought the boat from Scotty at Skunk Works:

Anodized blue alum strut and rudder setup
Alum adjustable motor mount
Octura coupling
.150 flex, 3/16 shaft w/bullet nut

I don't know if he made it, had it made for the boat or bought it off the shelf. It does look good on the boat though.

I don't have a picture, and I'm at work right now, but here is a pic. from Scott's post in the swap shop...

[ED66677]

the motor seems to be too much in the front, this hull has no step (am I wrong?) so it needs "help" to take off, my 29" require to have the batteries completely in the back (a bit less in rough water) while the motor is in the middle of the hatch opening!

[Boatman]

Wow! that is a sweet hardware setup, all one piece... nice. Ed, I was thinking and your prolly right but being it a shallow hull im wondering the more you move the motor back the sharper the angle of flex shaft would have to be in order to keep the motor above water line. I just wondering if the motor was kept further forward for that reason in mind. Also I think im gonna pretty much replicate the SV with mine and keep the motor around the c. of g. and move the packs for and aft to fine tune since I also plan on running a radio box just for safety.

On a side note I have had one of these hulls for some time and been waiting for parts to trickle in so I may start a build thread. Thanks for the excellent building pics gents!

[Chop]

O.K., spent the evening in the workshop with my 10 year old son. Taught him a bit about metalworking (DON'T brush the filings off with your hands!). Anyway, a 20 minute job took about an hour with him helping but he learned a lot by helping, and we had a blast! Just before he went to bed I asked if I could keep working on it and he was reluctant – he wanted to help and didn’t want me to go on without him.

Here are a few pictures. The first is the old part on the right, and our homemade part on the left. Bought a piece of 2” x 1/8” x 36” piece of aluminum bar stock at the local hardware store for $11 and had the rest of the tools at home (and had 35” of the aluminum left over for future projects). The original stock was very slightly less than 1/8" so the extra thickness might give me (us) an extra turn of the threads to prevent stripping them again.

I will admit, it was hard finding the 3m x 0.5mm tap for the four holes, but I found it!

Yeah, the big hole is a bit off, but that is a point where a little slop is O.K. Second picture is the part bolted to the motor.

Ed, you're right, it is a no step hull.

[tylerm]

the motor seems to be too much in the front, this hull has no step (am I wrong?) so it needs "help" to take off, my 29" require to have the batteries completely in the back (a bit less in rough water) while the motor is in the middle of the hatch opening!

Good to see you got one Ed! mine isnt too far away from running, just had a look at yours, looking good.

Tyler.

[ED66677]

Boatman, this is not a problem if you put your motor in the center of the opening in regards to the flex binding, I made my trans myself, two rigid shaft (one inside and one outside of the hull) and just 1" of 4mm flex between, what I mean here is that I made the same angle as you have to do but with a much shorter lengh of flex!!!... does not move at all!

yeah Tyler! got mine a month ago build it as fast as I could in 2 days, did a first short run before I left for vacation, put everything in the car and Wossssh! Gone!
This hull is amazing, I first put a positive prop angle upon some advices, CoG was at 30% but the baby would not take off, I was suspecting a surface effect because the lake that was just like a mirror, dead flat, then I went to another lake few days later, strong wind and 4" waves, FIZZZZZZZZZZZZZZZZZ! jumpin all around... twice as fast as before just by moving the CoG 2" back and zero prop angle.
Chop, I originally placed the motor where the CoG is now and the batteries where at the front of the hatch opening, now batts are at the transom!

BTW Tyler did you look at the vids? only 3S for the time being, not bad isn't it?, I'll run some 4S as soon as I get back home next week!!!

[tylerm]

Yea man it flys for just being on 3S! 4S it should rocket. They are a great hull, quite a few of his hulls are run down here.
BTW lookin good with yours chop.
Tyler.

[ED66677]

I think the 29" is a pretty good choice for a beginner, the hull itself and everything that is required to run is not very expensive, and the result is nice!

[ED66677]

Tyler, any of you have a flood chamber on this type of hull?
I'm asking because the first time she really did fly, in rough water, she went upside down and I had to swim!!! I'd like to avoid swimming in the future!!!

[tylerm]

na none with floodchamber down here, most are gas boats.
When i get home ill post a link i found to a guy who put one in a delta force 26.
Tyler.

[Chop]

Took the boat out today. It ran well, got up on plane pretty quickly and turns nice without any turn fins.

I noticed very little, if any water comming out of the cooling discharge hole so I brought it in. Didn't have a thermometer with me but the ESC and Lipo's had not a lot of heat, but the motor, WOW! It was really hot.

The cooling system on this boats has water making two passes through the ESC, and one through the motor. I'm sure that the several passes through the ESC creates a signifficant amount of back pressure. When I assembled the hoses I blew through the pickup and air came out the discharge, but there was a lot of resistance.

I suppose the obvious modification would be to add a second water pickup specifically for the motor? If the ESC was not hot, and there was no water flow, would it be safe to bypass the ESC and run the water directly to the motor (for a short run)?

Electrical set up was: KB36 11XL motor, Castle Creations Hydra 240 speed control, Elite 4S 4500 30c lipo’s. This all pushes a 42mm 3 blade prop.

[westbeach]

Can you guys tell me how well this hull runs in comparison to the Delta Force hulls. They look identical and all. And what is Scotty @ Skunk Works charging for one of this hulls?
Thanks

Neal

[Skunk Works]

Scotty here!

Been on the road.

Chop, looks great! I love that hardware package. Do have setups in the shop. Out of the 29 hulls at the moment. Quality is good, strong. The hardware is what makes this hull.

Cooling: Check the length on you tubes, want them to be short as possible. that may help.

[ED66677]

this hull handles great no matter the weather!

[westbeach]

So does the Skunk Works Vee come with hardware? What does the kit cost?

[Eodman]

Morning guys, One thing I noticed on my twin cat build - When I installed the fittings on the motor for cooling I got a little over zealous when I tightened the fittings down! I think they were to close to the motor causing the resistance. I backed them out and the flow improved greatly! Had to change the o-rings but it did help water flow!

[Chop]

So does the Skunk Works Vee come with hardware? What does the kit cost?

I think I paid $220 with hardware. Do a search in the Swap Shop and you will find several threads there that discuss cost.

Morning guys, One thing I noticed on my twin cat build - When I installed the fittings on the motor for cooling I got a little over zealous when I tightened the fittings down! I think they were to close to the motor causing the resistance. I backed them out and the flow improved greatly! Had to change the o-rings but it did help water flow!

Thanks Eodman, I'll check into that. I tried bypassing the ESC and blew through the cooling hose and still got a lot of back pressure. And the hose routing looks clean (no kinks).

[peells]

I am glad you got your water flow problem fixed,
I was reading above where you were concerned about the possibility of using stainless on your mount, if it was a good piece of stainless (USS steel not sure of the grade #s at this point) you would not have any problems with the dissimilar metal thing which causes electrolysis, the aircraft industry has been doing it for years, now if it was regular steel we would be talking electrolytic corrosion. and if a person was worried about it just use something to isolate the two parts( a little paint on the back side would do the trick), (which you wouldn't have to do any way it would have worked fine as is. when I worked on aircraft I would see this type of connection frequently.

[Chop]

I have some small pieces of 304L stainless and a few that are 316L stainless. I had forgotten about adding a "poision pad" to separate the two different metals.

Thanks.

[peells]

I doubt it would make any difference if you isolate the two.

[Chop]

I doubt it would make any difference if you isolate the two.

Probably not, it was just a thought I had when I was making the piece.

[Chop]

When I installed the fittings on the motor for cooling I got a little over zealous when I tightened the fittings down! I think they were to close to the motor causing the resistance. I backed them out and the flow improved greatly!

You might have hit the nail on the head Eodman. I removed and measured the fitting for the water inlet - it was 3/16 of an inch long, the thickness of the motor cooling jacket (outside of the jacket to the outside of the motor) was the same.

I filed the threaded end of the nipple(s) down about 1/16" and replaced. When blowing through the pickup hose there was moch less resistance!

I will try it out at the pond tomorrow.

[Chop]

Cooling water is running good now and I've been playing with the boat. This is another fun craft - Scotty does good work!

The boat has a Hydra 240 ESC and I just bought a Castle Link to program it with. I had all the settings right, except one - The low voltage cutoff was set at 5.0, I don't remember what I raised it to but it was supposed to be appropriate for 4s lipos. I can't find the different setting values anywhere.

Now when I hook everything up and pull the throttle trigger, the motor only "twitches."

Any ideas?

[Viking]

You may have set the low voltage cut off too high. It should be 3.2volts per cell or for 4S 12.8volts.
check that it is set up for 4S that can do it too.
Viking

[Chop]

Here are the current settings I’m using:
Cut off voltage: 12.0v
No Reverse
Reverse throttle amount: 12.5%
Motor timing: Normal 7
Start power: Low
Current limiter: Enabled

[Chop]

Anyone?