Joel's 25'' Radtek CF Mystic Twin

[srislash]

The bigger the props the faster....Right?

Just keep it light so you don't overwork those motors with those props Joel

[Rocstar]

Our single motor rigs like an extra blade to plane off quicker :

https://www.youtube.com/watch?v=JgRzweFct0M

[Darin Jordan]

Joel,

What rudder is that you are using?

[Rocstar]

Joel,

What rudder is that you are using?

It's the 2 3/16" rudder from Kintec.

http://kintecracing.com/Hardware.html

[keithbradley]

Looking good Joel!

For those asking about the drives:
I don't have anything against adjustable drives by any means, it's just a small boat with limited room.
These drives were manually machined from an aluminum billet to fit the 25" mystic. A lot of these boats are being built to see who can go the fastest, so I focused on allowing the use of 3/16" shafts and using ball bearings to keep friction low with high RPM setups.

[Darin Jordan]

It looks like I'm going a completely different direction with mine... Mine will be setup for a single. Hardware is going to be a challenge, with the minimal mounting area available, but I should have my mill up and running again here shortly (long story, but the parts I'm replacing the broken ones with should make it better than before... kind of like the Bionic man... :) so I am hoping to be able to fab up some nice pieces.

My rudder is NOT going to be in the center, however... Strut will be, but I feel that the rudder behind the prop just slows things down. Boat isn't going to turn well anyhow, but that's not the goal... the goal is a 2S, N2-Cat ROCKET! Using a VERY unconventional power system... Stay tuned!

[Rocstar]

... the goal is a 2S, N2-Cat ROCKET! Using a VERY unconventional power system... Stay tuned!

Look forward to seeing what you come up with.

[Fella1340]

Thanks guys for taking the time to explain things. My questions were based on what I have read
on the forum, no actual experience with either type of setup. I just wanted to get a handle on the "why" part of it being done so I could follow along. Great information!

[NativePaul]

Until post 13 I thought that this was the same as my H&M Agitator S (Negotiator) as the tops look very similar and that is around the same size at 610mm,

however the bottoms are very different as the Agitator has the ride pad bottom that I prefer (for my intended use) rather than the scale bottom of the Radtec, 610mm also turns out to be 24" not 25. The Agitator S also looks like it has a lot more room on the sponson transoms, as the fairing extension is fairly well hollowed out over the transoms making them much taller, though probably the same width.


Mine Sounds like Darin's it is a is a single and I am also not a fan of rudders behind props so I modified an ETTI 75x25mm wedge rudder so it would fit in the pocket behind the left transom where the stinger is shown above (normally I put my rudders on the right hand side, but it is not going to be turning ovals, and the linkage is better with the rudder on the left transom than the right). I use a standard ETTI 4mm ballraced strut on a bracket that I made to follow the contours of the rudder mount area (I was tempted to do an internal strut bracket and have the strut come up into the bottom of it, but difficulty of adjustment and fears of leaks stopped me doing it (if I was doing it again I would do an internal bracket with a hole for adjustment in the side that I could cover in tape for looks, the bracket mounted to the top rather than the bottom, cut the whole bottom off for ease of adjustment and so it doesn't trap water and put a false transom in just in front of the bracket so there is no chance of getting water into the main hull, practical, good looking and watertight.))

I have a 4mm-1/8" stub shaft in mine and though I do like the stingers shown here, and would be fin with no adjustment as there is always a file and sandpaper if it needs tweaking, I had assumed they would be for 1/8" stub shafts until I saw the massive props fitting. I'm fairly sure the props shown were a joke, but I am still surprised you wanted 3/16" shafts with 28mm motors, all my 28mm motors have run 1/8" props and I haven't even been at the big end of them, but then I have no twins and maybe you can get away with much lower RPM setups as you don't have as big a torque issue or need bigger diameter as are there are less high pitch right hand rotation props available. I am using a single 36mm car motor and a 35mm prop in my Agitator S.

[Rocstar]

I had assumed they would be for 1/8" stub shafts until I saw the massive props fitting. I'm fairly sure the props shown were a joke, but I am still surprised you wanted 3/16" shafts with 28mm motors, all my 28mm motors have run 1/8" props and I haven't even been at the big end of them, but then I have no twins and maybe you can get away with much lower RPM setups as you don't have as big a torque issue or need bigger diameter as are there are less high pitch right hand rotation props available. I am using a single 36mm car motor and a 35mm prop in my Agitator S.

Actually, twins allow you to spin higher RPMs more efficiently. And yes, the large props (6017s) pictured was just for fun. With 3/16'' shafts there are more choices for right hand props that can be cut down plus the added strength of the larger shaft. The H&M is a good looking hull btw.

[iridebikes247]

can't wait to see this one on the water. A hull this size is really a nice addition/entrant to the market.

[keithbradley]

Until post 13 I thought that this was the same as my H&M Agitator S (Negotiator) as the tops look very similar and that is around the same size at 610mm,

however the bottoms are very different as the Agitator has the ride pad bottom that I prefer (for my intended use) rather than the scale bottom of the Radtec, 610mm also turns out to be 24" not 25. The Agitator S also looks like it has a lot more room on the sponson transoms, as the fairing extension is fairly well hollowed out over the transoms making them much taller, though probably the same width.


Mine Sounds like Darin's it is a is a single and I am also not a fan of rudders behind props so I modified an ETTI 75x25mm wedge rudder so it would fit in the pocket behind the left transom where the stinger is shown above (normally I put my rudders on the right hand side, but it is not going to be turning ovals, and the linkage is better with the rudder on the left transom than the right). I use a standard ETTI 4mm ballraced strut on a bracket that I made to follow the contours of the rudder mount area (I was tempted to do an internal strut bracket and have the strut come up into the bottom of it, but difficulty of adjustment and fears of leaks stopped me doing it (if I was doing it again I would do an internal bracket with a hole for adjustment in the side that I could cover in tape for looks, the bracket mounted to the top rather than the bottom, cut the whole bottom off for ease of adjustment and so it doesn't trap water and put a false transom in just in front of the bracket so there is no chance of getting water into the main hull, practical, good looking and watertight.))

I have a 4mm-1/8" stub shaft in mine and though I do like the stingers shown here, and would be fin with no adjustment as there is always a file and sandpaper if it needs tweaking, I had assumed they would be for 1/8" stub shafts until I saw the massive props fitting. I'm fairly sure the props shown were a joke, but I am still surprised you wanted 3/16" shafts with 28mm motors, all my 28mm motors have run 1/8" props and I haven't even been at the big end of them, but then I have no twins and maybe you can get away with much lower RPM setups as you don't have as big a torque issue or need bigger diameter as are there are less high pitch right hand rotation props available. I am using a single 36mm car motor and a 35mm prop in my Agitator S.

1/8" prop shafts would be fairly at home on this cat. When I made those drives, I made them with SAW racing in mind. Twins are not allowed in N-cat here, but that doesn't mean we won't push these things just as hard. Over the year 2014, whoever can go the fastest with the 25" mystic will win a FREE Carbon Fiber Radtek 92" cat (Radek's layup of the HPR 233). This means there are going to be guys who are pushing these little cats HARD. It's possible that it could be done with 1/8" shafts, but it's definitely nice to know that we have a driveline capable of handling whatever we throw at it. You may be surprised at just how much power you can squeeze out of a 28mm motor!

[Rocstar]

So this is what I woke up to this morning....not good for motivation to build boats, but does help with the Xmas spirit I guess.





I did manage to get the motor mounts, tubes, and water pickups installed.

[srislash]

Snow is nice. You can run a twin in it. Hehe. Mounts look good Joel

[rawsonreyes]

cost of hull

hi guys what's the cost of the hull and drives,and where can you purchase it.thanks for reply.