HOTR twin build

[tiqueman]

Hey folks,
I picked up a HOTR a couple weeks ago here on the forum. She needed a bit of TLC, actually considered re-listing her, but decided Id need to make it right before or if I did that.

One thing that really bothered me was the rudder. The transom extension where the rudder bracket attaches was cut so that the rudder bracket would slide into the hull. Then the extension was filled from the inside w/ epoxy. Im still working on getting it all out, but the rudder bracket has been hacked off the back. Im still in decision mode on what rudder to use. I want something similar to the HPR 115 rudder, but w/ out the price tag.

[tiqueman]

I then started working on getting the twist out of the hull. There wasnt much, but the right sponson did sit about 3/32 off the table while the left was on the table. Also, I wanted to get the ride pads flat to the table as well. 3 days, some heat, several jigs, clamps, tape and a lot of patience and she is straight as an arrow.

[tiqueman]

I took some CF and made some motor mounts. They are not fastened yet as Im waiting on just a couple more things so I can place everything in the hull, move stuff around and find a good location for the Feigao 10XL motors.

Oh, and as you can see, I layed up the hull w/ 2x2 twill CF...

[domwilson]

Uh Oh! Somebody has caught the FE bug! Looking good so far!

P.S. did you try a heat gun or hair dryer in trying to remove the epoxy?

[Make-a-Wake]

Nice work so far! Twin XL's outta get it movin'!

[tiqueman]

Uh Oh! Somebody has caught the FE bug! Looking good so far!

P.S. did you try a heat gun or hair dryer in trying to remove the epoxy?

Dom.. if you only knew....

To remove the epoxy in the extension? No. I did use the heat gun to heat the hull I dont know how many times in the straightening process though.

Nice work so far! Twin XL's outta get it movin'!

I hope so. Im going to put it on a total of 6S. 2-3S packs in series and then split to each motor... I got a lot of info from Mudl while talking to him abou this twin BJ26. Seems like I should have a pretty sweet lil package when shes done.

[Simon.O.]

I'll be following this one with interest, I may twin my bigger cat soon. XL each side. Not yet decided how big XL's

I do like the idea of putting all of the battery power together and then splitting to the esc-motors. There was a long heated discussion here a while back about that and the jury is out on which is "right or wrong"
Some do a whole power system per motor and some paralell the power before the esc's

Fwiw, I am keen to paralell the power and then send it to the esc's

Watching with interest

[KillerDave]

Man! I'm doing a twin (380) HOTR but it is a comeback of the old Budweiser Select boat after it's fire.... I have been thinking of doing another with the XL's too... Can't wait to see how yours pans out... :-) Good job!!!

[tiqueman]

Thanks for the compliments gents. Yeah, Im anxious to see how she runs.

It came w/ SV stingers on it, but Ive decided to use them on another build and Im going w/ the HOTR anodized black Stingers. They are 4mm, but Ive been told you can drill them enough to install a sleave bearing and run 3/16 shafts. So thats the plan. Im going to try it out w/ Turnigy 120A Marine ESCs and Turnigy 3S 5000mah 35C batteries. A low pro Hitec servo (from OSE) for the steering... But still no decision on a rudder. I searched for hours last night. Got a few more ideas, but havent commited to anything yet. I was looking at using some alum C channel for a bracket, one cut in a wedge on each side and use an Octura blade.
Something like this but longer http://www.offshoreelectrics.com/pro...d=oct-oc4wrmca
MHZ has some nice stuff too, but not very informative on their bracket footprint size.

Any suggestions are welcome!

[BakedMopar]

Taked a look at these. Even has dual water pick-ups. Very nice and very nice price.

http://www3.towerhobbies.com/cgi-bin...?&I=LXXSN6&P=Z

[tiqueman]

Thanks Baked. Im suprised the EKOS only has a 75mm rudder? Thats what started my complete rebuild of another (single drive) 32" cat I have... rudder was too small. I do like that the pickups are seperate though, so I can delete them. I will be using thru hull so there is no tubing on the transom. I guess I could try my 75mm rudder and see what happens?

[bea5017]

wonder if u can get that for a push pull setup

[Make-a-Wake]

Just curious tiqueman..........are you running the 10XL's on 3s?....................if so it seems like not enough rpms?.........just over 20,000 unloaded...................

[tiqueman]

Just curious tiqueman..........are you running the 10XL's on 3s?....................if so it seems like not enough rpms?.........just over 20,000 unloaded...................

No, 6S

[Make-a-Wake]

Oh, Wow!!! Thats gonna be fun! I had read above where you had posted 3s batts..............over 40k rpms unloaded!

[tiqueman]

Im setting it up per a discussion w/ Mudl from the forum. 2-3S packs in series, then parallelled to each esc.

[RayR]

Im setting it up per a discussion w/ Mudl from the forum. 2-3S packs in series, then parallelled to each esc.

Kinda rough on the cells pulling 150amps plus continous.

All the best,

Ray

[eboat]

Kinda rough on the cells pulling 150amps plus continous.

All the best,

Ray

That is what I was thinking also when you were only using a one P setup

[ozzie-crawl]

that boat is going to be insane, i had mine in the 60s with 1 540xl on 4s
be interesting to see if it stays on the water

[JCAustralia]

Great craftmanship!!!

[tiqueman]

Kinda rough on the cells pulling 150amps plus continous.

All the best,

Ray

Again, as I said, it was suggested to set it up this way and has been proven to work. But, if I do have problems, changing to a different battery set up is the easiest thing to do. I will say that I am curious about it though, because those were my thoughts as well.

Ozzie, what XL? Did you ever finish your twin build? I saw it on another forum last night.

Thanks Jerome!

[tiqueman]

I tacked a motor mount in, trying to get the best fit for the motor. Is this too much bend for the stuffing tube?

[Rumdog]

As long as it spins freely you should be good. Can't you angle the motors more to get more of a straight shot?

[tiqueman]

I could angle it a couple more degrees. It will put the front end of the motor almost against the lip in the deck for the hatch though. The HOTR lip comes so far down! It is easy to spin.

[Rumdog]

How did you properly get the shape for the motor mounts?

[johnnyoverkill]

I tacked a motor mount in, trying to get the best fit for the motor. Is this too much bend for the stuffing tube?

Scott,

There are two bends in your stuffing tube, shoot for one, it will remove much of the cable drag. Also try switching out the teflon tube and run 1 size up on the cable. I removed all of the teflon from my .130 cables and now run .150 in the same tube. Just add grease and watch for the increase in rpm.

Good luck with it! I assume that this is the same hull that was marked H & M?

John

[tiqueman]

Johnny, yes, same hull. Its come a loooong way.

I broke the motor mount loose and angled it as much I could and re-tacked it. And my goodness.. I barely put any epoxy on it the first time and man it bit. Twas a bear to get out. Yeah, I didnt like the "S" bend it was beginning to make. Thats why I shot the ? out there to OSE land. It may still have a very small one, put I dont think near as much as it did.

Pics coming soon

[tiqueman]

How did you properly get the shape for the motor mounts?

oops, missed that ? The mounts that came in it were close.. but not quite. They were off the angled part of the bottom, that goes to the side. So the mount went from the flat part of the bottom of the sponson and then angled up and hit the side about 1/8 or 3/16 above where the bottom meets the side. And the mounts stopped at the hatch lip. I took a piece of balsa, traced the existing mount, then looked at the mount in the boat and drew on the balse where I thought it should be.. bunch of trial and error and I made a CF template. then made the mounts off that.

[tiqueman]

Dont know why I just didnt do it like that the first time...

Much better and now only one bend in the tube.

[bonewar]

I tacked a motor mount in, trying to get the best fit for the motor. Is this too much bend for the stuffing tube?

Tiqueman,

Here are my stuffing tubes out of the Twin Simrad Maritimo.
She spins the props at about 37k.
These little suckers get hot and the thick grease turns to fluid very quickly.
The less curve on your stuffing tubes the better for less friction.
Better to angle the motor high to get the soft curve.

Nice build buy the way.
Going to be very fast.

Bonewar