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Jul 13, 2014, 06:09 PM
Naval gazing
@P. Tritle, this looks great. Thank you for being such a great resource too.


You mentioned much earlier that you were delaying deck installation until you had installed the two motors but wouldn't have if you were going to be using just one motor. Does the kit have the option of setting her up for single motor operation?

I'm hoping so just because I'm on a budget.
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Jul 14, 2014, 07:49 AM
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P. Tritle's Avatar
Quote:
Originally Posted by spacephrawg
@P. Tritle, this looks great. Thank you for being such a great resource too.


You mentioned much earlier that you were delaying deck installation until you had installed the two motors but wouldn't have if you were going to be using just one motor. Does the kit have the option of setting her up for single motor operation?

I'm hoping so just because I'm on a budget.
Space, The kit is actually designed for one motor, and the running hardware kit #2370 provides everything you'll need to set it up.

As an added bonus, the instructions also show the location of the twin screw set-up, though there are no provisions given for mounting the motors. For those who want to go with the twin, you'll need two running hardware packs and a pair of counter-rotating props as well.

With the 2208 outrunner motors, I'm using one each #3133 & 3134, 1" counter rotating 3 blade brass props. The next size up is 1 1/2" dia. , which I think would be a little too big for the small motors. They would do fine with a 400 or 450 class motor, but I think that might be a good bit too much power for the boat. However, at this point it's pure speculation, but we'll find out first hand as soon as she's finished up and we can get her in the water.

PAT
Jul 14, 2014, 10:29 AM
Naval gazing
Sounds great. thanks. So I expect that you will be running lipo's right? Or could i use my 4200mah nicad 7 cell?
Jul 14, 2014, 11:49 AM
Registered User
Quote:
Originally Posted by the goon
jrobinsonusaf,

Welcome to the forum . Where do you hail from? I think you should start your own build thread on your Higgins. We all love to see pictures

Mark
Mark,

I am out of Charlotte, NC.

If someone can give me some guidance on posting pics, I think I might just start a thread on mine.

Joel
Jul 14, 2014, 01:58 PM
Big Boats Rule!
boater_dave's Avatar
PT's had three props all turning the same direction (right). In a small-ish scale model, the increased weight of three motors, esc's, shafts, tubes, etc. must be considered against a single. The difference is not speed, only 'coolness'. The same goes for twin, I guess. Perhaps low speed control would put a star in the multi motor column if you run split throttles. I have driven my single screw PT many times and have never had a problem doing what I wanted to do.
And use whatever battery type you want. Brushless motors do not 'require' lipo's. But lipo's are handy if you want to save weight, and a PT should be built as light as possible, if you want it to move quickly.
One last tip. When installing shafts in plastic hulls like this, do it after you are sure the hull is straight. Sometime there is a warp or twist in the hull because it's kinda flexible by itself. This will stiffen up when the deck is attached. But if you mount shafts to a twisted hull, then straighten the hull, the shafts will be skewed.

Dave
Last edited by boater_dave; Jul 14, 2014 at 10:19 PM. Reason: removed double name
Jul 14, 2014, 02:23 PM
Naval gazing
How does one straighten a hull if it is out of whack?
Jul 14, 2014, 11:07 PM
Big Boats Rule!
boater_dave's Avatar
Chech your hull for squareness before you commit to installing the deck. You can check the hull by laying a pair of straight edges across the hull, one at the bow and the other at the stern. Sight across the pair and their edges should be parallel. Also check that the hull is the correct width. Both of these can easily be corrected at the time of installing the deck. Secure the hull in the stand, or on blocks (anyway you can) so that the straight edges are parallel. Glue the deck on with the straight edges laying on top so you can see that the hull is still square. This is not such a big deal when you start with a framework of ribs, as they start out straight and square.

Dave
Jul 15, 2014, 12:09 AM
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MoonBlink's Avatar
Looking Good! If I knew about this kit I would of picked it over the PT-109. Looks allot easier to build.
Jul 15, 2014, 08:34 AM
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P. Tritle's Avatar
Quote:
Originally Posted by spacephrawg
Sounds great. thanks. So I expect that you will be running lipo's right? Or could i use my 4200mah nicad 7 cell?
I'll be using Lipo's for sure, but as with any uncharted teritory I'll start slow and work up. The first test runs will be done using 2 cells, probably a 2200 mah battery. Chances are, that'll be a bit less power then the hull will take, if so, will step up to either a 2200 or 3300 mah 3S battery and see how it goes. I'm not looking for rediculous amounts of speed, but rather, some good solid scale performance with maybe a bit of reserve.

PAT
Jul 15, 2014, 08:32 PM
Naval gazing
Quote:
Originally Posted by boater_dave
Chech your hull for squareness before you commit to installing the deck. You can check the hull by laying a pair of straight edges across the hull, one at the bow and the other at the stern. Sight across the pair and their edges should be parallel. Also check that the hull is the correct width. Both of these can easily be corrected at the time of installing the deck. Secure the hull in the stand, or on blocks (anyway you can) so that the straight edges are parallel. Glue the deck on with the straight edges laying on top so you can see that the hull is still square. This is not such a big deal when you start with a framework of ribs, as they start out straight and square.

Dave
My apologies but I'm still unclear on the actual straightening method. Perhaps I'm missing something obvious but you describe putting the straight edges on there and making sure they line up - but if they don't then what happens when you glue the deck on?
Jul 16, 2014, 09:28 AM
Registered User
Quote:
Originally Posted by spacephrawg
My apologies but I'm still unclear on the actual straightening method. Perhaps I'm missing something obvious but you describe putting the straight edges on there and making sure they line up - but if they don't then what happens when you glue the deck on?
I use temporary chocks to level the boat side to side, using the chines as a reference. If you do this, when you place your levels across the beam at the bow and the stern, they should line up. If they do not, place a temporary shim between the chock and the bottom of the hull on the low side to twist the hull into alignment. It would also be adviseable to doublecheck the distence from the centerline of the hull to the edge of the transom and the beam at multiple points along the hull. After you glue the deck in place, it should maintain the correction once you remove the hull from the chocks. Hope this answers more questions than it creates.

JR
Jul 16, 2014, 01:41 PM
Big Boats Rule!
boater_dave's Avatar
What JR said. Securing the hull to the stand/blocks/shims may require temporary weights placed inside to help hold it down. By itself, the hull can be twisted easily by hand. It's not like a rigid molding that has the warp set in place. It's just so flexible that it's easy to let it set up in the wrong position. It's just like folding the top of a cardboard box together. Pull/push/press the sides to make the flaps line up before you apply the tape. Once the tape is on, the box is much stiffer. The Lindy PT and, I assume, the Dumas PT, both have the deck sit on top of the edge of the hull, so there is plenty of room for it move around. Once set up, trim the excess deck off and your all set. Some kits have an inside lip to help things line up.

Dave
Jul 16, 2014, 04:35 PM
Naval gazing
Thanks. Sounds good. I kind of wish Dumas made this and other kits as a hybrid vacuum formed hull with wood frame like vac u boat does on their hydros.

I read years a go on rcg that abs plastic can warp in hot sun. Is that really true?

Edit: so a plastic hull won't try to spring back to its prior shape much? Is there any sort of reinforcement I can put in it to help keep it in the right shape in the future? Well I mean I know there is but is there a recommended method or can I fudge it with putty in key areas?

Also I was wondering if it would be a good idea to give it two rudders rather than one that blocks the shaft for when I want to pull it out and is there a prescribed method for making them upright rather than at right angles to the portion floor that they are sitting on?
Last edited by spacephrawg; Jul 16, 2014 at 04:43 PM. Reason: Needed to revise a question
Jul 17, 2014, 02:08 PM
Big Boats Rule!
boater_dave's Avatar
A good plastic hull will sit straight by itself, but flex with a little pressure. That's the problem. As you are clamping the deck in place when you are gluing it on you can cause the twist. And the deck is the piece that will hold everything straight. I added a few braces under the deck on my Lindy PT's because there are large unsupported flat sections that can move around. I know in the Dumas kit there are long runners that go along the sides of the hatch opening to support the deck.
It's pretty common to offset the rudder post just enough to get the shaft past, but unless you can't easily remove the rudder too, why bother? If you are servicing the prop shaft you should probably be servicing the rudder shaft too. And I would think unless you have two shafts, two rudders would be more hassle than they are worth.

Dave
Jul 19, 2014, 10:56 AM
Naval gazing
Is there a special method for centering the motor, stuff box, and whatever else or are there marks inside the hull? Also how is alignment achieved when there are two motors?


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