Fixing the BJ26 Handling Issues

[MAXAMUS]

yeah Ive already read that report also had some info from another source saying that some guy was running stock with 4s in parallel with speeds up to 50mph ?? could this be true ? getting back to my awaiting order issue seems iam awaiting a shipment from horizon to the UK approx 3 weeks also a true mare trying to get hold of a octura x642 here in the UK everyone seems to be out of stock any ideas from across the pond with cheap shipping e-bay nothing seen on there either ..........have dubro SW on order though and where is there a direct link to the correct items for the fullers hop up inc all other bits

maxamus the sponge for info lol

[ETOWNE]

I have a question if anyone knows. I ordered Fuller's hardware last week. I sent the order in for the cat hardware. Ray, called and said the Hydro hardware is the one to use for turning right. This set-up came w/ 1 1/2" down strut that sits off of the transom like a Hydro setup.

1. Where should I mount the strut ? Right at the bottom of the boat ? Do I need to offset it a bit to make up for the prop ?

.The rudder is offset and is 1 1/2 inch from the center of the mount to the hinge. Rudder itself is 2 3/4" from the bottom of the rudder mount.The rudder looks like it will sit on top of the strut and allow (the strut)adjustment up. This way only allows 3/4" to 1" away from the prop. The rudder is about 3 inches away from the prop if I mount it to the side of the strut.

2. Which way of mounting the rudder is better ?

[PropNutt43]

PropNutt- Did you have a chance to run the packs more? Also what balancing tabs does it come with? HP/PQ?

Yes, I have run them 5 or 6 times now and they just keep getting better. Ran them with my x642 prop today timing set to high and again just got luke warm after non stop WOT run. The run times seem to be getting longer too. Here are the complete specs on the batteries:

Spec.
Capacity: 4300mAh
Config: 7.4v / 2 cell / 2S1P
Discharge: 20C Constant, 30C Bursts
Weight: 246g (entire pack. Not only combined cell weight)
Size: 145x45x18mm
Plug Style:JST-XH

[ETOWNE]

I have a question if anyone knows. I ordered Fuller's hardware last week...............
.

I called Fuller today. I mount the strut right at the bottom of the hull. Also, I put the rudder mount right above it. It's done.

[PropNutt43]

yeah Ive already read that report also had some info from another source saying that some guy was running stock with 4s in parallel with speeds up to 50mph ?? could this be true ?

If you are looking for all out speed read some of Obrien's threads. He is one of the few here to break 50mph with this boat.

Finally broke 50!
http://forums.offshoreelectrics.com/...ead.php?t=2200

Finally tried Lipos
http://forums.offshoreelectrics.com/...ead.php?t=2345

As far as doing 50 with the stock setup I think it would be highly unlikely.

[Joe007]

Well finished modding my blackjack today...
I followed PropNutt43 directions and have added acouple of others things...
Thanks to PN43 for showing us how to make our boats handle better...
I will post some pictures of my BJ in acouple of days... Going to the lake tomorrow to test and tune...
Joe007

[MAXAMUS]

hi guys just been scouting about and seen this

http://cgi.ebay.ca/Aluminum-rudder-and-strut-for-electric-boat-catamaran_W0QQitemZ290233656861QQihZ019QQcategoryZ34058QQcmdZViewItemQQ_trksidZp1742.m153.l1262

how would this do for the BJ ???

[PropNutt43]

Yeah, I've seen this too. It looks to be of fairly good quality everything has a nice finish and there are bushings in the strut. Would probably work ok on the BJ26 but you will have to deal with a couple things.

1st:
The flex shaft and stub shaft are 4mm so you would need an adapter for the stub shaft if you want to use 3/16" props. Might be able to use the one that comes on the stock BJ26 drive but I'm not sure of the inside diameter if it's 1/8" or 4mm.

2nd:
Because the flex shaft is 4mm you might need to change the coupler on the motor from .150 to 4mm if it won’t hold the flex shaft tight enough.

3rd:
The front of the strut looks like it comes farther forward than the back of the transom of the boat so you may need to cut the stuffing box tube back a little to make it fit right.

If you can live with all that it should work ok on this boat.

[MAXAMUS]

Well I've seen the light and iam gonna wait a while then go with the fullers cat hardware after all the reading I've done over the last week there are a few that are a no no for sure plus i like the look of your set up last i read you were still trimming out hows things now ? what sort of speeds are you reaching ant whats the spec of your lipo's ?

[PropNutt43]

I would like to clear something up, it was never my intension to prove that Fullers Offshore Catamaran Hardware is “The best hardware” I don’t believe any one set up is. It all depends on what you are trying to accomplish. You should choose what best fits your needs and goals.

For me, I want stability at top speed, meaning the boat won’t blow over backward easily. I want it to turn both left and right at any speed without flipping upside down and I want it to turn like it’s on rails. Breaking speed records isn’t one of my intensions for now because the main pond I run in is too small to be going 50+mph.

There is lot of good quality drive hardware out there. What I would like to see is more people stepping up and showing off (with pictures) what other setups they have gone with and (documenting with details) if they have accomplished what they wanted to. This way we can all learn more from each other and have more choices to go with. So please share your boat mods and accomplishments.

[PropNutt43]

Back to Maxamus questions. Yes, I’m still trimming out my boat and probably always will be because I’m continuously looking to get a little more out of it. It’s getting very close to what I’ve been looking to accomplish.

Since I started running Lipos I’ve played around with the turn fins some more. I’ve remounted them back in the original holes and slotted the bottom hole on each turn fin so the angle can be adjusted and tightened down. With Lipos the boat seems more stable with less angle on them than I had originally.

As far as what kind of speeds I’m running couldn’t tell you for sure don’t have a gps yet but it is on my list of things to get. If I had to guess I would say some where in the low 40mph range.

I am trying to get some decent video footage and will post it later. In the mean time here are some pictures of my boat at the pond in front of my subdivision.

BJ26 at the pond 001.JPG BJ26 at the pond 002.JPG BJ26 at the pond 003.jpg

[MAXAMUS]

great photos
well iam still waiting on my BJ to arrive my other items have or are winging there way to me as i type lol

lipo programmer
switch mount
octura x642 b/s/p
2x 7.4v 6600mah lipo's
a predator z which will be my rescue boat

http://www.raidentech.com/1scprzrareco1.html

with a few mods using carbon rods and pool noodles

so all i need now is my BJ

do you know where the CofG is on the BJ and how crucial is it to be on in the running ?

[PropNutt43]

do you know where the CofG is on the BJ and how crucial is it to be on in the running ?

I never checked the CG with the stock drive. With the Fullers hardware on and NiMH batteries in stock location it is about 7.75 inches from back of transom forward, with Lipos 7.50 inches.

So far I’ve had the best results with the CG set at 6.50 to 6.75 inches for NiMHs and 6.75 inches for Lipos. NiMH location 3” to 4” back from stock, Lipos 2” back.

As far as the CG being crucial, it is very important in how the boat will run. The closer towards the transom you go the more speed you will get but the wider your turning radius will become. The boat will also tend to blow over backwards easier. The farther away from the transom the less speed you will get but turning will be tighter. Prop angle and depth will affect these things too.

[Joe007]

Pronutt, so you put your turn fins back to the stock location.. Does that mean you put the fins back in the stock alignment where they are almost straight up and down... Also so you are saying that you do not have the turn fins following the the angle of boat so that the boat will track better in turns as you stated before..
Joe007

[PropNutt43]

I put the turn fins back in the stock mounting holes which are strait up and down and also lower than where I had them before. I still have them angled in at the bottom but not as much as before. The turn fins are now adjustable because I used a small hobby file to slot the lower hole in the turn fins.

Here are some pics:

BJ26 Fin Angle 001.jpg BJ26 Fin Angle 002.jpg BJ26 Fin Angle 003.jpg BJ26 Fin Angle 004.jpg

I am still playing with the angle of the turn fins and will be shortening them some. Length is back at 1" below ride surface right now.

Here is some video with this setup.


http://youtube.com/watch?v=Mqv1GBGQfKc (You Tube)

Sorry about the quality its avi. converted to their format.

Here is a link where you can download the same video but better quality.

http://www.savefile.com/files/1603610 (Download)

Hit the download button on the site page then click on download file now.