Help Completing an Old 1/10th Scale Build

[Reid Cuddy]

My dad started this build a very long time ago, and I recently found it at his house stored away. I would love to surprise him by finishing it up myself but I don't have any experience building and it seems that he doesn't have any hardware or directions whatsoever. I think I remember him saying that this was a 1/10th scale Pay 'n Pak kit, but I'm really not sure. I was wondering if there was anyone out there that still had the directions to a kit like this, as I have no idea what size/type of hardware I would need for it, or where to or how to install it. I'm not even sure what size engine 1/10ths run, as I only have some experience with 1/8th scale. Any information would be a great help. Thanks in advance!

 

[ChrisCapaldi]

Hi Reid, How long is the hull? Dumas made some hulls that looked like this that were for .21s as well as .45s. The length should tell which engine size will be correct for it.
Chris

 

[Hydro Junkie]

I have that kit at home under construction right now so it would be difficult to give you the plans. With that said, I can help you out a bit:

• You can get a rudder assembly that will work from Speedmaster. You will have to shorten the blade a bit to make it work however
• The onboard radio gear goes in the area between the two full height bulkheads aft of the sponsons
• Check on the inside of the right sponson. Is there any holes through it? If not all is good, TO A POINT!!!
• You will need to remove the bottom of the right sponson and install a doubler(assuming there isn't one there). I believe you can get a fin and (maybe) a bracket from Mike Hughes as I got my fin from him
• Since you have the 1/9.5 sorta-scale boat, it will need a .21, preferably with the exhaust port over the flywheel. The narrow engine bay won't accept a 180 header without widening the engine bay
• IIRC, I got my strut and flex cable(s) from Aeromarine

I'll see about posting some pictures when I get home from work

 

[Grimracer]

I this the 30 inch boat?

 

[Hydro Junkie]

Hi Reid, How long is the hull? Dumas made some hulls that looked like this that were for .21s as well as .45s. The length should tell which engine size will be correct for it.
Chris

Chris, Dumas made both a sport 20(30") and 1/8 sorta-scale(43") kits with Pak markings and a sport 40(36") with the 1976 Atlas markings. I don't know if the Atlas version had decals or not but I do know that neither version of the Pak did. The instructions explained how to do the Pak graphics with Monokote and supplied the patterns to do the deck, wing and cowl top letters and striping

 

[Reid Cuddy]

Hi Reid, How long is the hull? Dumas made some hulls that looked like this that were for .21s as well as .45s. The length should tell which engine size will be correct for it.
Chris

Hi Chris,

The boat measures roughly 36" in length. Thanks again!

 

[ChrisCapaldi]

Hi Reid, At 36" then that is probably as Mark noted above, an Atlas Van Lines Sport 40. It could be finished as a Pay n Pak if you choose as they were the same hull.
Chris

 

[Grimracer]

sport 40 indeed.. nice!

 

[Hydro Junkie]

No wonder you can't find plans or anything else, that kit's been out of production for over a decade. Same things apply as I posted originally though, to be honest, I forgot to give the doubler location. That would go on the inside of the right sponson transom. If the boat uses the same mahogany framing I've seen on other kits, I would recommend adding a thin ply facing on the outside of the sponson transom as well as the mahogany can compress. Obviously, the engine would need to be enlarged to a .45. The exhaust still needs to come out over the flywheel since the engine bay is still too narrow for a 180 header

 

[Hydro Junkie]

The lower picture shows where I located the Speedmaster rudder and Aeromarine strut on my Sport 20 Pak build. They're located in the same locations as the stock Dumas parts would have been. The rudder bracket location has the rudder in the same location as the Dumas rudder bracket would have it. Interestingly, it is actually too close to the prop when compared to the full-sized boat in the upper picture below boat

 

[Reid Cuddy]

No wonder you can't find plans or anything else, that kit's been out of production for over a decade. Same things apply as I posted originally though, to be honest, I forgot to give the doubler location. That would go on the inside of the right sponson transom. If the boat uses the same mahogany framing I've seen on other kits, I would recommend adding a thin ply facing on the outside of the sponson transom as well as the mahogany can compress. Obviously, the engine would need to be enlarged to a .45. The exhaust still needs to come out over the flywheel since the engine bay is still too narrow for a 180 header

Hi Mark,

I do remember seeing two holes in the transom of the right sponson. I will take a closer look internally next time I have access to the hull this weekend. Since it appears the radio box goes into the center of the hull, will I have to run the tuned pipe over the top and have it visible, rather than under the deck? I was really hoping that that wouldn't be the case but I understand it's an old kit. Then I think I would need the motor mounts, stuffing box, and motor itself. What would you recommend for that? I have a CMB .67 Greenhead for the 1/8th but not familiar with anything in the .45 range.

 

[Hydro Junkie]

As I see it, for the tuned pipe, you have three choices:

1. cut down the radio box width and run the pipe under the deck like you would a scale boat
2. install the rear center deck separate from the tails (the instructions, at least for the sport 20 kit, call for the center deck to be part of the cowl assembly and attached to the tails) and run the pipe over the top of the center deck
3. do what the sport 20 instructions call for and don't run a pipe at all, let the exhaust go inside the boat

Of the three, I ran the pipe on my sport 20 down the right side of the engine bay and out through the transom and that would be my preferred solution.
As far as the motor, A CMB or Nova Rossi 46 would be your best bets since both are available here in the forum. The 67 would be too much power for the hull though some did use 40s in the sport 20 so, if the engine bay is wide enough........
The stuffing box could be a piece of brass tubing, bent as needed to work with either a flex cable or wire drive. Mine has a flex cable as shown. I did make one major change;
the radio is now in the front of the boat instead of in the middle

 

[Reid Cuddy]

As I see it, for the tuned pipe, you have three choices:

1. cut down the radio box width and run the pipe under the deck like you would a scale boat
2. install the rear center deck separate from the tails (the instructions, at least for the sport 20 kit, call for the center deck to be part of the cowl assembly and attached to the tails) and run the pipe over the top of the center deck
3. do what the sport 20 instructions call for and don't run a pipe at all, let the exhaust go inside the boat

Of the three, I ran the pipe on my sport 20 down the right side of the engine bay and out through the transom and that would be my preferred solution.
As far as the motor, A CMB or Nova Rossi 46 would be your best bets since both are available here in the forum. The 67 would be too much power for the hull though some did use 40s in the sport 20 so, if the engine bay is wide enough........
The stuffing box could be a piece of brass tubing, bent as needed to work with either a flex cable or wire drive. Mine has a flex cable as shown. I did make one major change;
the radio is now in the front of the boat instead of in the middle

Thank you so much for the input. I'm really considering doing this, I guess the main questions I'd have left are the locations of things. I'm assuming your fuel tank is under the deck on the side if your radio box is up front (which is what I'd like to do, but probably can't do easily now that the deck is laid). How will I know where to put the motor mounts, strut, rudder, etc.? Maybe I could take your locations relative to the hull and use a ratio to expand it to the 40 size?

 

[Hydro Junkie]

This is where things get fun.

• I built my boat more scale, hence the strut through the bottom of the hull. In the Sport 40 class, I believe you can mount the strut on the outside of the transom. If not, the rules that apply to a scale would apply here as well
• I put the rudder right at the end of the engine bay wall on the left side of the boat. I know some do the same on the right side(builders choice) I put it there so that the strut hardware don't interfere with the rudder push rod and so the rudder servo pulls the rudder into the right hand turn. The added benefit is that the rudder bracket is in a more solid location, frame wise
• The motor and motor mounts need to go as far forward as you can get then to fit, mostly due to balancing the boat. My boat's forward bottom has been changed so that the bottom break in two cross frames further aft than where it is supposed to be(that being at the sponson transom. One thing you need to be careful of is that the hull design has the fuel tank located under the fixed nose cowl. You need to make sure you can get the tank in and out as needed.
• I won't give any recommendations on locating the radio gear since it really depends on how you run your tuned pipe and if you need to cut the box width down or not.

Hope that helps