Trumpeter 1/144 Gato build

[He Who Shall Not Be Named]

The plastic is a fine bushing here, and don't apply any lubricate -- it will screw up the later putty, primer, and paint work. The only real loads on the shafts are axial and they are presented to the motor and idler gear bearings (a flat-head machine screw serves as an astern thrust bearing for the free-floating idler gear). The stern tube (that the proper term, not stuffing tube -- were not stuffing anything in there!) and strut 'bearings' only see lateral loads and those are small if you bore those plastic fairleads with .068" holes. Propeller shafts are .062" brass or stainless rod.

M

[He Who Shall Not Be Named]

The plastic is a fine bushing here, and don't apply any lubricate -- it will screw up the later putty, primer, and paint work. The only real loads on the shafts are axial and they are presented to the motor and idler gear bearings (a flat-head machine screw serves as an astern thrust bearing for the free-floating idler gear). The stern tube (that the proper term, not stuffing tube -- were not stuffing anything in there!) and strut 'bearings' only see lateral loads and those are small if you bore those plastic fairleads with .068" holes. Propeller shafts are .062" brass or stainless rod.

M

[crazygary]

Roger that. M!!
Many thanks!

[crazygary]

Roger that. M!!
Many thanks!

[crazygary]

Fairleads???? Was ist los???

Being relatively new to the sub world, are the fairleads the parts that attach to the hull where the prop shafts exit??

If those are what you're referring to, I'll need to cut off the injection molded prop shafts and drill through for 1/16"
brass shafts. Si?? No??

[crazygary]

WTC saddles have been "massaged" so that my 1 1/4"SD sits in there pretty nicely!
A little hobby knifing, a little filing, a little sanding, and she's good to go!

Forward saddle looking aft...


Aft saddle looking aft...


The SD from my little 1:230 Skipjack will be driving the Gato, too!
Will have to lengthen one of the tubes so it overlaps the two saddles. As it is now, only 1 of the saddles is holding the SD. Got a foot of
1 1/4" lexan tubing coming from McMaster-Carr! Great place! Their motto should be, "If we don't have it, you don't need it"!

Top view of SD installation...


Forward saddle with SD...


Aft saddle with SD...


Next I'll be working out rear dive plane linkage and rudder linkage. Want to do this now so that
I can glue the hull halves together. I won't be using the forward dive planes, as they're probably
gonna make for a pretty unstable sub. However, I'm kind of thinking I'll make them manually
retractable for show, and fold them up for "go"!!

Too much fun stuff here!

crazygary, out!

[He Who Shall Not Be Named]

Fairleads???? Was ist los???

Being relatively new to the sub world, are the fairleads the parts that attach to the hull where the prop shafts exit??

If those are what you're referring to, I'll need to cut off the injection molded prop shafts and drill through for 1/16"
brass shafts. Si?? No??

A fairlead is any fixed item that passes a line or shaft that has to move within with minimum friction. With the running gear on your little GATO, the strut bearing and stern tube fairleads the propeller shaft.

Yeah, you'll have to bore those out to pass the 1/16" propeller shaft.

M

[crazygary]

Piece of cake!!! NOT!!!!!

But, us old poop machinists can handle whatever gets thrown our way!!

Hardy old dawgs we are!! AAAAARGH!!

[crazygary]

I chose the aft dive planes for this mornings adventure!

First thing that needed to be done was to eliminate the square mounting lugs on either side of the "skeg", and fill in the
corresponding square recesses in the dive planes themselves. The red arrows point out the areas in question.


Prior to removal of the "square pegs", I drilled, very carefully, through the center of them to assure proper positioning of
the dive planes. Pin vised a 3/64" drill bit through first, and followed that up with a .064" diameter drill bit. I chose to go
with a 1/16" diameter shaft as the thickness of the "skeg" is just under 1/8", and want as much "rigidity" as possible.

Here the "square pegs" have been removed, and the dive planes filled in. I used some styrene I had laying around to fill them in,
and left the filler piece on the portside plane a little longer so I can insert the operating linkage, which will be "through-the-hull"! I may not have left enough, but will find out later!!

I used the same procedure to drill the shaft holes in the dive planes
except the holes were drilled with a 1/16" drill for a nice fit with the 1/16" diameter shaft.

Next photos show the 1/16" shaft in place and the assembly of the dive planes.


Off to "tackle" the rudder next! Will be using 1/32" diameter brass wire for the rudder shaft as I'm still
having to deal with a pretty narrow assembly!!

Film at eleven!! Hah!!

crazygary, out!

[crazygary]

Just a quick "plan" change to my last post regarding the aft diving planes!

Now hear this....! The port plane is now the starboard plane!! That is...the port plane is now the starboard plane!!

How come, Grasshopper?? Well, cuz' that extra little bit fer the operating linkage is interfering with the rudder!! Cain't be there!! (Duh!!)

Fortunately, the aft planes are interchangeable from one side to the other!!

TA-DAAA!! Problem solved!!

Back shortly with the rudder info!!

crazygary, out!

[crazygary]

Got the rudder set up! Carefully measured, marked and drilled through the top of hull and down through the
lower rudder pivot point. Used a 1/32" diameter drill bit as I'll be using a 1/32" pin to pivot the rudder on!
(Kinda makes some sense, no!!?)

Drill that hole first, then the rudder can be put into place so you can drill through that,too! (Big fun! NOT!)

However, due to the extremely small amount of room inside the hull way back there, the rudder linkage
will also be a "through-the-hull" arrangement! More info to follow when I git 'er done!!


Quite a bit of sanding and fitting of the rudder is needed in order for it to "play nicely" with the other parts of the puzzle!
It's a P.I.A. to make happen, but works well! Got about 45 degrees of swing from side to side!! Wow!! Talk about "evasiveness"!! YEEEhah!!


Here's a photo of the "whole enchilada", as far as controls go!!!


This one shows that the "port plane is now the starboard plane"!! (Ya had ta be there!!)


That is all! Tune in tomorrow as the "crazy one" here attempts to fab up linkage so we can make turns, and go up-and-down!!

crazygary, out!

[He Who Shall Not Be Named]

Well done, sir!

M

[Sublime]

Got the rudder set up! Carefully measured, marked and drilled through the top of hull and down through the
lower rudder pivot point. Used a 1/32" diameter drill bit as I'll be using a 1/32" pin to pivot the rudder on!
(Kinda makes some sense, no!!?)

Drill that hole first, then the rudder can be put into place so you can drill through that,too! (Big fun! NOT!)
[ATTACH=CONFIG]26041[/ATTACH]
However, due to the extremely small amount of room inside the hull way back there, the rudder linkage
will also be a "through-the-hull" arrangement! More info to follow when I git 'er done!!


Quite a bit of sanding and fitting of the rudder is needed in order for it to "play nicely" with the other parts of the puzzle!
It's a P.I.A. to make happen, but works well! Got about 45 degrees of swing from side to side!! Wow!! Talk about "evasiveness"!! YEEEhah!!
[ATTACH=CONFIG]26042[/ATTACH]

Here's a photo of the "whole enchilada", as far as controls go!!!
[ATTACH=CONFIG]26043[/ATTACH]

This one shows that the "port plane is now the starboard plane"!! (Ya had ta be there!!)
[ATTACH=CONFIG]26044[/ATTACH]

That is all! Tune in tomorrow as the "crazy one" here attempts to fab up linkage so we can make turns, and go up-and-down!!

crazygary, out!

OK, I have an idea that needs to be run by you'all. You want to put external controls on those rear surfaces with through the hull control rods. I'm running into the same issue with the rudder on my Type XXI. I was told to do the same thing (not to Rube Goldberg some sort of internal control). Yes, I hate to admit I knew who he was talking about. But! That word always gets me in trouble. What about soldering a tiller (rudder stock if you are from across the pond) to the rudder post. Can one of those linear servos be placed perpendicular to the direction of submarine travel to move the tiller left and right? I guess I'm asking if those linear servos that come with the SD fit in sideways?

[crazygary]

Hi, Sublime!

I don't know that mounting a linear servo sideways is going to get you anywhere near where you want to be.
It would probably require a whole lot more room than physically available.

I'm planning to anchor some sort of horn on the side of my rudder on which the pushrod can have the ability
to swivel on that end. The other end will go directly to the servo. Magnets are a really sensible choice for connecting points here!

I've got some on order from Gaussboys and will make good use of them for control surface operation. I'm also
planning to use some of them to attach my Gatos' deck to the hull. Will have to fab up some mounting hardware,
but should be pretty straight forward. I'll post what I did when I get to that point in this build.

I'm sure David will chime in with better information than I gave you! If anyone can get you on the right road, it's "The Man"!

[He Who Shall Not Be Named]

I don't see any reason why you can't carve out a slot within the rudder skeg halves to accommodate a bell-crank! You CAN operate both the rudder and the stern planes from internal pushrods that need not venture outside the confines of the stern.

Also, when you operate this model, you want the bow planes rigged out -- their planing action works to grab the water as the stern planes change the boats angle of attack about the pitch axis. See, Type-17.

M