H&M Intruder twin build

[tlandauer]

So I had asked some questions a while back, this is on my mind for a twin build for sometime. Joel ( ROCSTAR) did a fabulous job for CF inlay ( never attempt to do a job when there are professionals around to help was my thinking, so i sent the hull to him)
8F5E4BE4-1CE3-4D41-A718-FB0C34531A6C_zpsyjssgwey.jpg4A82D212-7BF8-4268-9A4D-B07F7916510E_zps5wuasbai.jpg
2950B181-8CAB-430B-AC30-F34A9B8A1F64_zpskozhloqa.jpg
Prior to sending him the hull, I made transom doublers for the main transom and the sponson transoms.
DSCN7180.jpg DSCN7182.jpg

[tlandauer]

I have some questions regarding the position for the stingers. It is a rather small real estate in the back and it's not absolutely flat, the picture shows a "sweet spot", is this OK? I know that in powerful twin cats sometimes if the stingers are mounted too low, there might be too much lift and also unloading props may be an issue, but this is a small hull and I am not setting it up for SAW.
Please take a look and give me some feed back. THANKS in advance!!

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[olwarbirds]

Tim, I am no help far as where the sweet spot is on this hull as I am trying to learn about building a fast twin myself. It sure is a nice looking hull. I am a big fan of H&M hulls and do wish we had a good North American supplier of them. Good luck on this build and I will be tuned in brother... Happy Holidays... DJ

[srislash]

I know we discussed this Tim but if you can get them inward a bit it would be nice. The height looks good.

[tlandauer]

Tim, I am no help far as where the sweet spot is on this hull as I am trying to learn about building a fast twin myself. It sure is a nice looking hull. I am a big fan of H&M hulls and do wish we had a good North American supplier of them. Good luck on this build and I will be tuned in brother... Happy Holidays... DJ

Thank you, I am hoping at the very least this would turn out to be a good ''practice run". I regret to try my untrained hands on a H&M hull, but I like the challenge this particular hull presents.

I know we discussed this Tim but if you can get them inward a bit it would be nice. The height looks good.

Shawn, yes, and i remembered your advice, thanks again. I drilled the holes and the issue is if I move them anymore inward, there is a bump and will cause the stingers to have a pronounced "toe-in" viewing from the back.
Anyway, I did my singer per your suggestion and now i got two nice Hughey .150 cables for the build!

[tlandauer]

So as slow as it is, I am using easy materials to get everything close to the final version.
As i posted somewhere else, since there is no template for the motor mount, here is my "CAVEMEN" approach:DSCN7229.jpg DSCN7232.jpgDSCN7234.jpgDSCN7245.jpgDSCN7248.jpg

[tlandauer]

DSCN7253.jpg DSCN7255.jpgDSCN7249.jpgDSCN7256.jpg DSCN7258.jpg
I also drilled mounting hole patternes for TP 29xx motors, since these seem to be the last of the out-runners from FightCat. In case I don't have replacement motors, plan B is to use 29xx motors.
Thanks for putting up with me guys, I know there are so many better builds and more interesting pictures. I am truly grateful for this Forum and all the people who are selflessly helping newbies like myself.

[Ken_NJ]

Can I ask a general question about CF? I'm use to using polyester resin or Z-Poxy. Have not worked with West yet. What do you guys use with CF cloth?

BTW, I'm following along and learning myself! Right there with you.

[tlandauer]

I didn't do the CF inlay myself, I had Rocstar did it for me. So I don't know what he used ( think he used West as well) , but I have done many FG inlays using West, it is great and I like it, because the viscosity is low enough that you can reposition many times( West 105 /206) . Z-poxy 30 min. epoxy is great but in general MUCH TOO Thick, IMO for any inlay work, the only alternative is their Z-Finishing -Epoxy. It is great stuff but I have done some tests: the cured left over in the mixing cup of the Z-Finishing Epoxy is more brittle than the left over West in the mixing cup. Now, I don't know much about what kind of quality is wanted in an inlay, but for mounting motor mounts or other tasks , I will mix some milled FG or filler to THICKEN the WEST epoxy, and the result is bullet proof.

[TheShaughnessy]

You can use the z poxy finishing resin, pt40 but it isn't nearly as hard as west systems, west is a much better structural resin.

Looking good so far Tim, twins sound so cool.

[Rocstar]

I used West System 105 with 207 clear hardener.

[keithbradley]

Cool build Tim. Are the batteries and ESCs both going in the tunnel, or are the ESCs going to be in the sponsons?

[tlandauer]

Cool build Tim. Are the batteries and ESCs both going in the tunnel, or are the ESCs going to be in the sponsons?

Thanks, Keith!
The batteries will be on the tunnel floor , at least the majority of 5000mah/4s would not go in the sponsons without grinding away some of the hull---one of the reasons why I decided to make a twin out of it. My plan is to use two SK 120ESC and place them ahead of the motors in the sponsons.
I hope this is OK, especially for the correct COG.

[tlandauer]

Trying to see how the stuffing tube should be bent.DSCN7259.jpg DSCN7265.jpgDSCN7261.jpg
Although I will be using .150 cable, for alignment purpose, I use a 3/16" aluminum rod to line up the motor, I plan to use teflon liner as well, but I prefer to have a solid rod for this step.
Moving to the real thing:DSCN7266.jpg DSCN7270.jpg

[tlandauer]

DSCN7271.jpg DSCN7270.jpgDSCN7273.jpg DSCN7274.jpgDSCN7275.jpg
Once I get the angle really correctly, I will tack the motor mount, then gingerly take down the motors and epoxy them GOOD, also I need to make stuffing tube supports.
Having only a power drill and a Dremel is proving to be a PITA for this build. I will buy fewer boats and invest in some tools.

[tlandauer]

Got a bit more done:DSCN7276.jpg DSCN7293.jpg DSCN7294.jpgDSCN7296.jpg

[tlandauer]

I wanted to use the TFL rudder, but on this particular hull, there is no "build-in" rudder platform that extends from the back of the tramsom, please take a look and tell me if i need to fabricate a extender and how far? I thought off set rudder's leading edge should be roughly where the drive dog is. Is it the same for cat hull's center rudder as well?
Also, I want to have dual cooling, the TFL dual pick up rudder is a lot bigger, would that be a problem? The small sponson rear pad makes sponson pick up a difficult proposition, what do you guys think?
DSCN7302.jpg DSCN7306.jpg DSCN7305.jpg
Third picture is of single water pick up rudder.
Thanks!

[royalcasa]

Trying to see how the stuffing tube should be bent.DSCN7259.jpg DSCN7265.jpgDSCN7261.jpg
Although I will be using .150 cable, for alignment purpose, I use a 3/16" aluminum rod to line up the motor, I plan to use teflon liner as well, but I prefer to have a solid rod for this step.
Moving to the real thing:DSCN7266.jpg DSCN7270.jpg

What did you use to bend the tube.
This is looking very nice. you are not as slow as you claim to be. lol I am much slower.:)

[tlandauer]

Thanks!
I have a discarded .187 cable, and I slip over this cable a teflon liner that is meant for a .150 cable. It is hard to slide it on, but most bend is no longer than 4", so all I did was have the liner on the .187 cable for about 4".
This only works for 1/4" tubes, BTW, since this tube can be used for .150 with liner and .187 w/o liner, my contraption is serving me well, all you need to do is insert the cable+liner and start bending away.
Some people put sugar in the tube and seal both ends, I haven't tried yet, but in any case I prefer not to heat up the brass tube in the process.

[srislash]

L

I wanted to use the TFL rudder, but on this particular hull, there is no "build-in" rudder platform that extends from the back of the tramsom, please take a look and tell me if i need to fabricate a extender and how far? I thought off set rudder's leading edge should be roughly where the drive dog is. Is it the same for cat hull's center rudder as well?
Also, I want to have dual cooling, the TFL dual pick up rudder is a lot bigger, would that be a problem? The small sponson rear pad makes sponson pick up a difficult proposition, what do you guys think?
DSCN7302.jpg DSCN7306.jpg DSCN7305.jpg
Third picture is of single water pick up rudder.
Thanks!

Tim, the rudder depth in pic one looks good(approximately) but in pic two that looks deep and with those pickups at the bottom cutting that sucker is out. Can you mount the rudder up higher on that transom/cowl? You can do your servo rod mounting under the rudder arms. Progress is going well buddy. It wasn't so long ago that a drill and Dremal were about all I had, I had my hand tools too but found a hammer not so good for boat building.

[tlandauer]

Thanks! HAPPY NEW YEAR!
What about the distance from the transom, you have a few twins I remember and those fantastic videos! what is the conventional wisdom on that.
I agree with the rudder depth, guess i will settle for this one and see if I can put transom pick up.

Sent from my D6708 using Tapatalk

[srislash]

I have been putting the leading edge of the rudder is even with the leading edge of the props.

That being said, my R-42 shall have all kinds of rudder adjustments via the Speedmaster standoffs and struts because I am curious how things handle with the rudder in front of the props.

[RandyatBBY]

What did you use to bend the tube.
This is looking very nice. you are not as slow as you claim to be. lol I am much slower.:)

That is a good way to get it correct. I have done that a lot over the years when I wanted to get it right.

[tlandauer]

Slow progress: I wanted to see how the rudder would look if mounted a bit further than the pictures in post #17 had shown. Using 2.5mm CF plate I Dremel'ed these bits by hand .
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Here is how it looks like on the hull:

[tlandauer]

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Here is a side view:DSCN7328.jpg What do you guys think? Should I run it like that or leave the rudder stock? It was more of a "looks" issue to me than actual concern for turning ability.
Also the rear overhang from the transom is extremely low, not much vertical room to mount hard ware, I hope I can mount the servo standing up and use pull-push rods:DSCN7340.jpg
I can always bend the rods and mount the servo horns below the servo arm. More fiddling, but I am back to full schedule work.

I have also toyed with the idea that with a side laying servo, using just one rod, and leaving the other " idle" for symmetrical look.
Any inputs would be greatly welcome.

[royalcasa]

Thanks!
I have a discarded .187 cable, and I slip over this cable a teflon liner that is meant for a .150 cable. It is hard to slide it on, but most bend is no longer than 4", so all I did was have the liner on the .187 cable for about 4".
This only works for 1/4" tubes, BTW, since this tube can be used for .150 with liner and .187 w/o liner, my contraption is serving me well, all you need to do is insert the cable+liner and start bending away.
Some people put sugar in the tube and seal both ends, I haven't tried yet, but in any case I prefer not to heat up the brass tube in the process.

got it, I take it that the inserted cable prevents the tube from kinking and you get the clean curves.
Thanks,

[srislash]

Tim, you should be able to put the bends in the rods to suit whatever. Just make sure they are on 45degrees or less to avoid deflection. Or you could run cables, lol.
I like the standoff, pretty slick.

[tlandauer]

Tim, you should be able to put the bends in the rods to suit whatever. Just make sure they are on 45degrees or less to avoid deflection. Or you could run cables, lol.
I like the standoff, pretty slick.

Got it, and thanks!

[Fella1340]

The build is looking great, you should give your building skills more credit. I like the standoff to, double servo arms would look the best.

[tlandauer]

The build is looking great, you should give your building skills more credit. I like the standoff to, double servo arms would look the best.

Thank you very much!
I like to be modest, that way I am more willing and open to learn and accept my mistakes as well.