Fixing the BJ26 Handling Issues

[hex-dj]

Well I tried my Blackjack with the fins angled inwards, with stock hardware. It definately does not help. The boat hooked real bad coming out of corners and lost some straight line speed.
]

True. Mine even flipped from the left side from a very sharp turn. It does not help. I was using an Ammo 2300 kv though.

[PropNutt43]

As I have said before I never ran the fins angle with the stock hardware on my boat.

What I can tell you is that I did have the same problems of hooking (spinning out) and losing some speed when I first put angle on the fins.

After running "many times" playing with the prop angle and depth, moving the center of gravity back, and shortening the fins all that went away.

[PropNutt43]

The Problems:

Angling the fins at the stock length causes the boat to run wet, meaning it pushes the front of the boat down.

Running wet reduces your speed and affects the boats turning causing hooking (spin outs).

Fixing the problems:

Shortening the fins reduces the affect of pushing the front of the boat down. 1/2 to 1 inch below the ride surface works best. More stable at 1 inch but much faster at 1/2 inch.

Moving the center of gravity back at least 1 inch will eliminate the hooking
(spin outs).

Raising the prop height and adding a little positive angle will get the speed back up.

[PropNutt43]

Also I have seen pictures on the forums of the turn fins being bent to put angle on them. Only by leaning them over can you be sure they are at the right angle in relation to the length of the hull. If the angle is off it could cause the boat to track funny or even hook.

[chirotray]

I dont have the upgraded hardware yet, but ive been playing just with center of gravity and prop angle. And on my boat with the cg back a bit, and prop up a bit, it aint too bad! Prob not race competitive, but plenty to impress people at the lake! The more i drive it the faster im comfortable turning. I think a little practice on this boat goes a long way.

[rahallva]

fins

Thanks for the info on the turn fins guys . Will wait on angling them awhile

[MAXAMUS]

yipeeee

its arrived at last fresh from Florida in under a week !!

OK to work 1st question the motor mount is not parallel the wooden base mount should this be ?? see attached picture

also what are you guys blocking up the canopy semi circular holes with + antenna hole ? also where the water pick up rubber tube enters the hull at the rear are you waterproofing this and with what ? that should keep me busy for a while now to start some mods

a happy maxamus........

[Wakesurfer]

Wow, the motor mount is looking pretty far out. Try to line it up so it's square and centered on the shaft log. A little clear hatch tape over the hole in the canopies will help keep water and dirt out the pilots faces. I've had good luck taping the hatch down with white electrical tape. Sticks well for keeping the edges sealed but comes off easy after a run. I used it to tape around the ant. hole too, until I ditched the stock Rx for a Spektrum. Never had any leaks around the cooling hose. Big common leak is at the end of the shaft log. Cut about 3/8" off of one of your cooling hoses and slip it on over the end of the log. Put the shaft back in and slide the tube forward so it just touches the shaft and it will help keep it sealed up. Grease the shaft well too. Have fun with it.

[MAXAMUS]

Wow, the motor mount is looking pretty far out. Try to line it up so it's square and centered on the shaft log. A little clear hatch tape over the hole in the canopies will help keep water and dirt out the pilots faces. I've had good luck taping the hatch down with white electrical tape. Sticks well for keeping the edges sealed but comes off easy after a run. I used it to tape around the ant. hole too, until I ditched the stock Rx for a Spektrum. Never had any leaks around the cooling hose. Big common leak is at the end of the shaft log. Cut about 3/8" off of one of your cooling hoses and slip it on over the end of the log. Put the shaft back in and slide the tube forward so it just touches the shaft and it will help keep it sealed up. Grease the shaft well too. Have fun with it.

thanks have lined up the mount removed bat trays done the switch mod just in the final touches of the antenna mount any chance of some pics for the shaft tube ? but thanks alot

[MAXAMUS]

Hi all

well I've just finished work but now down to real work i arrived home to find my fullers cat hardware has arrived so looks like this will take up most of my afternoon all these mods and the thing hasn't been near any water yet ! lol hoping to get down the pond first thing tomorrow and hopefully post some pics and video all going well .......................

could some one please list or point me into the right direction for fitting the fullers cat hardware including fitting and cutting the 150 flexi shaft i know I've seen it somewhere on this forum but cant find it

[lancel]

I believe you mean this pic.

[ATTACH]4602[/ATTACH]

What you see is 30 minute epoxy coating the transom at the rear of the boat. I have drilled more than a few holes in the transom and had too removed some of the wood that doubled up the thickness where the turn fins were originally mounted.

Reason for coating:

Wanted to waterproof the areas that were no longer coated in fiber glass. Also to strengthen around the edges and areas where the turn fins and drive hardware are mounted. You can see it better in this pic.

[ATTACH]4603[/ATTACH]

Propnutt43 - What brand coating did you use?

"What you see is 30 minute epoxy coating the transom at the rear of the boat. I have drilled more than a few holes in the transom and had too removed some of the wood that doubled up the thickness where the turn fins were originally mounted."

[kookie_guy]

hey propnutt, I borrowed one of your pics to ask a question, hope you don't mind....

1) the red measurement. why is it so long? Could this be shortened to bring the prop assembly closer to the transom and reduce the blue distance? If not, then why?

2) is the green measurement critical? Why or why not?

Thanks for any answers.

[PropNutt43]

Propnutt43 - What brand coating did you use?

Any 20 - 30 minute epoxy will work. I have been using stuff from my local hobby shop. It's distributed by Bob Smith Industries.

Originally I used their 30 minute epoxy but later found their 20 minute epoxy comes in finish cure which leaves a much thinner coat. Thinner coat, less weight, much better.

[MAXAMUS]

OK iam off to the pond tomorrow hopefully armed with a HD video cam and a camera providing my bro in law turns up and weather permitting

have now moved the dog nut away mm's from the strut re positioned the flexi tube to be more parallele, have re greased flexi drive added a bit of shrink tube from the stuffing tube where it exits the hull to the strut to keep water out made another water pick up from brass tubing and a small plate as of propnutt's design. will see how things go and will report back ..............




left to do ..............shorten fins and angle

MAXAMUS........

[Loki]

Ok WOW!

First off fantastic information, but I must say that I’m such a newb I’m a bit scared to just jump in and start doing all the tweaks. I’ve been flying Helicopters for a little while now and just bought an Apache 24 to run around my pool. Needless to say the bug bit me and now I’m looking to get something with a bit more… umph.

I LOVE the look of the BJ26, but now must admit I’m a little worried about how many tweaks it takes to get this thing working… great. So my question is pretty basic.

Should I be looking at another Boat since this one appears to have some issues right from the gate, or is there a version 2 coming out that addresses some of the faults?

Is there a shop that sells the boat and will do the needed tweaks to it or am I looking at doing this myself?

Thanks for any info