Midwest Harbor Tug x2 - Page 2 - RC Groups
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Mar 15, 2016, 08:51 PM
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Tim B.'s Avatar
This little Tug Is cool, there are utube vids showing 'er at work, wish there was more info on it.
Last edited by Tim B.; Aug 15, 2016 at 01:33 PM.
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Mar 15, 2016, 09:27 PM
Old wreck in Milwaukee
Prins Willem's Avatar
Quote:
Originally Posted by Garage Ape
Prins Willem, thanks for the thought but I am already committed with the props. Both are 45mm, the smaller blade one (177) has a pitch of 46.1mm, the larger blade one (175) has a pitch of 40mm. I think they will be okay, but time will tell.

Looking at both Raboesch and Prop Shop charts, both show the same pitch for both 3 and 4 blade for a given diameter.

The Prop Shop props do have slightly more pitch than the Raboesch of the same diameter.
They should perform close to the Midwest/Graupner prop which was 2" pitch. At 25.4mm=1" you are right in the ball park.
Mar 16, 2016, 11:07 AM
hangin' around
Garage Ape's Avatar
Tim B - Thanks for the additional photos, I hadn't stumbled across those.
Look closely at what is perched on the handrail on the front of the pilot house! It is a stuffed Pluto dog, identical to the one perched on my headboard. Too cool!
Thanks
Don
Mar 16, 2016, 09:01 PM
hangin' around
Garage Ape's Avatar
Transferring all of the formers and various pieces onto their respective pieces of wood has taken me a while, been working at it several days. With the plans taped down to the board I taped the sheets of wood underneath and used carbon paper to trace the pieces onto the wood. I had to take many breaks, standing at the bench slightly bent over gets to my back. A set of big curves would have been nice to have had to use on the long graceful curved parts. I had to freehand them but think I did okay. Now I'm ready to start cutting out the parts, that will take a while.
Mar 16, 2016, 09:54 PM
hangin' around
Garage Ape's Avatar
While laying out the parts I was thinking about motors and batteries. As I have mentioned I do have a Dumas #2004 6v motor that will go in one of the tugs, probably in the older well used one direct driving the smaller blade prop. I think I'll call it the "Mule". For a battery I'm thinking of a 7.2v 3000ma or 5000ma nimh depending on what will fit. It doesn't look like there will be a lot of room in the hull and a gel cell/SLA setup may be impractical. Hopefully some of you guys that have built this tug will chime in on this.

I am still thinking about the setup for the other tug with the large blade prop, which remains nameless at this point. Please feel free to chime in with suggestions.
Mar 17, 2016, 10:53 PM
Registered User
DON- I thought I would post my thread I did on the Laughing Whale/Midwest Harbor Tug many years ago. Might give you some ideas. By the way the model runs great.

https://www.rcgroups.com/forums/showthread.php?t=456378
Mar 18, 2016, 09:37 AM
hangin' around
Garage Ape's Avatar
Thanks Rich! Nice boat.
Mar 18, 2016, 09:31 PM
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Garage Ape's Avatar
The power package for the 2nd tug (think I'll call it "Stallion") has been decided upon. It was arrived at by soliciting the advice of frankg (Rich Koll). It will consist of the MACK #1885G motor w/gearbox utilizing the 3:1 gear set, powering it with 2- 7.2v NI-MH batteries in series for 14.4v, which should give about 4850 rpm to the prop at full power according to Rich. I plan on using the largest ma batteries that will fit in the hull, hopefully 5000ma. Fortunately, to that end I opened up the frames as I was laying them out for more interior room than is shown on the plans. It will be interesting to have the two tugs with different power set ups for comparison. So there we have it, the "Mule" & the "Stallion". Corny huh?

Well, guess I'll get back to cutting out parts.
Mar 21, 2016, 09:29 PM
hangin' around
Garage Ape's Avatar
Finally managed to get all of the pieces for the hulls of both tugs sawn out (rough cut) with the exception of the rail caps. Decided to wait to cut those out later when they are needed. The ape in me would probably manage to break them if they were laying around, being that they are so long and thin. I still have a few small cuts to make with a hand held razor saw where the limited throat depth of the band saw would not let me get to.

I am making a few deviations from what the plans call for.
1st, the keel is going to be made of two pieces of 1/8" birch ply laminated together.
2nd, I am going to use a thin perimeter sub deck inset down into the top of the ribs. This should give me better access to the interior of the hull until I install the full deck at a later stage of the construction. The plans called for a 3/32" basswood full deck, I'm using 1/16" birch ply for the sub & full deck.
3rd, I am going to open up the interior cut outs of the ribs for more room in the hull, which I will do after sanding the outside of the ribs to final shape.
Lots of tedious sanding ahead.
Mar 22, 2016, 07:22 AM
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Tim B.'s Avatar
Those material selections all sound good for strong hulls ~
Mar 25, 2016, 09:48 PM
hangin' around
Garage Ape's Avatar
Managed to get the ply keel pieces, the ply deck pieces and the stern pieces final sanded to shape. The left and right hand pieces were clamped back to back and sanded at the same time to ensure being symmetrical.
The slots for the ribs in the sub deck and main deck pieces were cut out undersized and filed with a flat needle file to the correct width while the pieces were clamped together using a scrap piece of wood as a thickness gauge while doing so. This should also ensure that the slots are in the same fore/aft position on both sides. I also used a square to check & adjust perpendicular areas, and the flat of a level to do the same for long straight areas.
Some scrap PVC pieces wrapped with sand paper came in handy for sanding inside curves and of course a sanding block was used on outside curves and straight areas. I hope all this will payoff when it starts to go together.
I also cut out some frames for a stand for each tug out of some scrap Redwood pieces that were left over from doing the ceiling on our patio cover. The Frames allow for using 3/16" thick felt.
Apr 01, 2016, 02:10 PM
hangin' around
Garage Ape's Avatar

Look what came today!


Motor, stuffing box & shaft came in the mail today. Need to get couplers next.
Apr 01, 2016, 02:13 PM
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Tim B.'s Avatar


...........
Apr 01, 2016, 04:45 PM
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Garage Ape's Avatar
I know this has been boring so far, nothing assembled and nothing much to look at yet, but all necessary steps to get there.

Having two sets of frames I was able to use them together to check for symmetry. What I mean by that is I took both #1 frames with the center lines lined up and compare them when orientated front to back, front to front, and back to back. Then both #2 frames and so on down the line. By doing this the frames that are reasonably symmetrical (off by less than 1/32" in all orientations) will show themselves to be so, and the ones that are not symmetrical will be readily apparent.

4 of the 7 sets were good and only required very minor sanding to correct. 3 sets were off, so for those I cut them into left and right pieces along the center-line, clamped them together back to back, then sanded them to the same shape thereby making them symmetrical when assembled back together. These will be glued back together and reinforced.
I also made a mock up of a small section of the keel to use as a guide to sand the keel slots to the right size.

I had noticed when laying out the frames that the far right side of the plans were a bit off, lines that should have been straight were not, deformed if you will. Don't know if it was the original plans, the scan, or the print. I tried my best to compensate for it at the time and tried to be careful and accurate when cutting them out.
All in all, I think it turned out okay. Nothing was way off and relatively easily corrected.
Apr 14, 2016, 05:26 PM
hangin' around
Garage Ape's Avatar
After cutting shaping the frame extensions, gluing them to the frames, gluing the halves together and adding a little reinforcement, I now have two completed sets of frames.
I have started gluing the keel pieces together, I only have enough clamps to do one at a time. The 1/8" ply pieces I used had a bow to them so the pieces were cut and glued with the bow direction opposite of each other. 30 minute epoxy was used and the pieces were clamped to a flat MDF board, temperature will be kept above 70 degrees for the full 24 hr cure. Hopefully they will end up straight.
Interestingly another member,"Mducati25", managed to acquire a kit and posted a pic of the kit keel pieces, which have stepped areas that I just flat did not pick up on when reading the plans and laying out the keel pieces. It appears that the steps would help to locate several of the frames. Fortunately I marked the locations on the outside of each of the keel pieces.


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