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    Dumas Higgins PT boat
    by Cashrc ๐Ÿ‡บ๐Ÿ‡ธ ( Captain)
    ๐Ÿ“ฃ










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    17 Posts 61 Comments 0 Photos 111 Likes
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    ๐Ÿ“ Video with big Jupiter and the PT
    3 months ago by Cashrc ( Captain)
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    Hi yโ€™all. Iโ€™m posting a video from this weekend, first half is Larryโ€™s big 50 inc KnK Jupiter, the second half is the PT212. Iโ€™m happy to say that even though she turns better port than starboard, Iโ€™m quite pleased with her. Now, I can have a bit of fun with her and concentrate on tweaking ballast/power/handling๐Ÿ˜Š
    North Texas Shipwrights @ Josey Ranch April 18
    โ–ถ๏ธ
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by wingsounds13 ( Able Seaman)
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    Easy enough to observe in the video (or in person) that at speed this boat does turn much better to port than to starboard. Back off a bit from full power and things get much better, but at or near full power starboard rudder basically causes the boat to heel well to starboard but she hardly turns (or will even continue straight ahead while heeled over about 45 deg.).

    Slower her down a little Cash, it looks much better and sails better too.

    I can definitely help with OpenTX programming. We could do a multi-stage stepped rate change with throttle or a continuous rate change with throttle. Either one can have different rates port and starboard as you see fit.

    A little more tuning of the boat and a lot of tuning of her skipper and she'll be running just fine. ๐Ÿ˜€

    J.P.
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by Cashrc ( Captain)
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    Thatโ€™s on the table for the 212. Next outing I plan to play with different props to see what she does and how that affects handling. Going to tweak the fore-aft trim also, and play with OpenTX and see if I can make up a throttle controlled rate mix on starboard only. I like PTโ€™s, but if I build another itโ€™ll be 2 motors and counter rotation props.
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by jbkiwi ( Fleet Admiral)
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    Hi Cash, looks pretty good๐Ÿ‘. I'd suggest you try a smaller prop and spin it faster, as a prop which has too large a diameter will cause that torque roll (especially with one prop) Try going right down in size (25 mm 2 blade for eg) then work up. To give an example of what I mean, have a look at my Maiami camera boat vid in the media gallery (somewhere),- it only has a 25mm 3 blade (very little pitch) with a 380 brushed motor, spinning at about 12,000 rpm but stays dead flat, and turns the same each way. My Thorneycroft MTB has the same motors and props x 2, spinning the same way but still turns well both ways.

    You might have to be happy with the more scale speed.

    JB
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by Cashrc ( Captain)
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    Fleet, LT Errol will be in command of the PT15, once she is brought back up to speed. Our naval engineers have come to the conclusion that the PT15 is a bit more of a cruiser than a MTB, and the tests of the PT212, and subsequent problems and successful resolution of trim and range problems suggest the methodology used to get the 212 in operational status should be successful with the PT15 as well. Once the boat has passed our test regime, LT Errol and crew will be patrolling Lake Texoma to give the Oklahoma Rabbit Regulars a much needed thrashing.
    I will be in command of the 212, however until the 15 is fully operational I can see both Errol and I in joint command. I trust this will be satisfactory for both the Texas Navy and the RN.๐Ÿ‘
    Commander Cash Hargett
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by RNinMunich ( Fleet Admiral)
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    Congratulations on a successful construction Commander ๐Ÿ‘
    BUT: Knock off the fun if you please Cdr. and complete the shake-down training, to get Lt. Errol ๐Ÿฑ and his crew up to speed for controlling them thar pesky Oklahoma wabbits!
    FLEET// ๐Ÿ˜Ž
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by Martin555 ( Fleet Admiral)
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    Nice to see her on the water Cash.
    With this hobby there are two types of fun, Building Then operating.
    I am glad you have and are enjoy it.

    Martin555.
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    ๐Ÿ’ฌ Re: Video with big Jupiter and the PT
    3 months ago by ToraDog ( Midshipman)
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    Very nice! She does swing a bit wide to starboard. Part of that could be the props swinging the same way. If I may, I would suggest that you check to make sure that the rudders have the same swing, side to side, no more than 35 degrees. Also, if they do, check that your servo is centered when your rudders are. Don't be afraid of taking some swing from port and transferring it to stbd.This will open your port turn a bit, but tighten up your stbd swings.
    Really nice job. PT's always cut such a fine line in the water.....
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    ๐Ÿ“ Better!!! Much better
    4 months ago by Cashrc ( Captain)
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    Hi yโ€™all. I had decided that after work today Iโ€™d go down to the Cottonwood Creek Baptist test pond (to be known hereafter as CCBTP) and run the PT. Sometime before I left for home, it started to rain..!!?##$$!!
    It let up as I pulled in the driveway, so I ran in, said hi and bye to wife and daughter, grabbed said boat and TX and headed to the pond. I didnโ€™t have the battery centered, but itโ€™s started to rain again so I made a few passes, and sheโ€™s a lot better. I would lose signal about halfway to the fountain, this time it was good all the way there and back. It turns left well, turns right ok, I still have a hard roll to right at full power and hard rudder, but itโ€™s manageable now. The wind was up and it was sprinkling heading to rain so I called it quits after 5 minutes but Iโ€™m on the right track. Now itโ€™s a question of trim and balance, and Iโ€™m pretty sure Iโ€™ll have to adopt my handling of this boat to its idiosyncrasies. But, for now, Iโ€™m good. If we donโ€™t get rained out I hope to have more progress made this Sunday at Josey Ranch.
    Cash
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    ๐Ÿ“ One problem down one to go
    4 months ago by Cashrc ( Captain)
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    Hi!! So...this morning I took the PT to my local test pond, conveniently located on our Churchโ€™s property. I looks as if I have the ballast about right, although with a 7 cell pack she rides a bit too bow high, but perfect on a 6 cell. Turns sharply to port, not quite so much to starboard, you have to be a little more careful with rudder and power than to port...but, quite acceptable๐Ÿ˜€ However, I could only do tests close in for a short period of time as I lost all range about 70 feet from the bank...and to make matters worse, the wind took her under the fountain ๐Ÿ˜ฑ. She stayed dry enough for me to walk around the pond and picker back up in range and โ€œwalkโ€ her back. I decided I had enough, upon inspection the receiver was relatively dry in spit if the fountain bath. I concluded that I was just going to try another receiver, as I uninstalled the rx I tugged on the antenna slightly and it came right out!! Iโ€™ve concluded that I had a sketchy intermittent signal the whole time. The receiver in question is a FlySky GR3C bound to a Radiomaster 16S multi-protocol transmitter. Iโ€™ve had no problems with another of these receivers mounted in my PBR. Anyway, I have other receivers to use, but I found a waterproof version of the same receiver for 14.00 shipped from Amazon, so thatโ€™s whatโ€™s going back in the PT. I will get that installed and do a proper range check and another pond test, once Iโ€™m satisfied with the range I can finalize my trim, but in spite of all the drama Saturday I fell that I have made progress in that regard. Iโ€™ll update as soon as I can.
    Thanks for all the help and comments, especially concerning PT boats turning radius both full size and scale. Itโ€™s been a big help๐Ÿ‘
    Cash
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by RNinMunich ( Fleet Admiral)
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    "Is it an aircraft carrier that will be big enough for Errol ?"
    Will it be big enough for Errol ๐Ÿฑ to do press-ups on the flight deck? ๐Ÿ˜๐Ÿ˜‚
    Or is he down below on the propulsion treadmill? ๐Ÿ˜ฎ
    ๐Ÿ˜Ž
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Cashrc ( Captain)
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    Sorry it took so long to respond Larry. Iโ€™m running a 3 blade at this time. Now that I have my range issue fixed Iโ€™m going to play with battery weight and placement plus take a range of props with me. The plan is try to get her dialed in Sunday.
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Martin555 ( Fleet Admiral)
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    Hi Cash,
    Thank's
    I am looking forward to the Grimmershorn Build Log.

    Martin555.
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Cashrc ( Captain)
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    Hi Martin!! I think my next project is a Krick Grimmershorn. I bought the kit for my birthday. I turned 60 this past January, and I had been putting funds aside for the kit and my new transmitter, so when I pulled the trigger on both it wasnโ€™t a hard hit to the budget. The Grimmershorn is a good size pilot/working boat, sheโ€™s 40 inches long and quite wide. Sheโ€™ll be the biggest boat Iโ€™ve built yet, and I plan to add lights and sound to her. Might have to coerce Errol to take a nap in the bottom of the hull for ballast๐Ÿคฃ
    Glad youโ€™re back Martin..missed you buddy..
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Martin555 ( Fleet Admiral)
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    Well Cash you have been a busy boy.
    Your boat looks fantastic, and I really like the paint job.
    Despite having a few problems that i am sure you will sort out I think you will enjoy wizzing her around the pond.

    Now the question that everyone will like to know the answer to.

    What is next ?
    Is it an aircraft carrier that will be big enough for Errol ?

    Martin555.
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by CaptLarry ( Chief Petty Officer 2nd Class)
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    Cash,
    They are somewhat, still a plaining hull is affected by propeller torque. It is a function of ascending and descending blade caused by pitch attitude, and direction of blade rotation. This is why runaway boats veer off to the left when the helm is unattended (eventually causes helm hard-over).
    Are you running a 2 or 3 bladed screw?
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Cashrc ( Captain)
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    Jonathon, my buddy JP is very knowledgeable about OpenTX, in fact I think he helped with the project a bit as it was and I think still is an open source OS
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by Cashrc ( Captain)
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    Larry, one question. I thought PT boats were planing hulls. Am I mistaken or are they a little of both. When I hear the term displacement hull Iโ€™m thinking of hulls like my little Coast Guard boat and my tug. Correct me if Iโ€™m wrong please sir.
    Cash
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by ToraDog ( Midshipman)
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    Cash,
    it sounds like you are making good progress. Well done. Too bad about your antenna, but it appears to be an easy fix. I am using OpenTX on my FrSky X9E to run my fleet. It seems to me, and I am WAY out of my depth on OTX, that you should be able to set up an automatic dual rate for you rudder based on throttle position. I am not sure that this is allowed, but on RC Groups forum there is thread dedicated to just OTX and the folks are quite tolerant of folks like me, still using a rotary dial phone, asking very rudimentary questions. I would strongly suggest that you try approaching them, or another forum dedicated to OTX.
    Another skin the cat suggestion is to consider splitting your battery pack. Whether this will help you at all, I don't know, but it will sometimes allow you to distribute their weight more to your advantage.
    All in all, it sounds like you are almost there. Bravo Zulu. I would love to see some photos of her in action.
    Jonathan
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by CaptLarry ( Chief Petty Officer 2nd Class)
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    Oh by the way, that is with rudder amidships.....if you have very much freeboard, windage may affect the accuracy of your test.
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    ๐Ÿ’ฌ Re: One problem down one to go
    4 months ago by CaptLarry ( Chief Petty Officer 2nd Class)
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    Cash,
    Is your PT a single screw? If so, then your turning problem is related to propeller torque. Common on all displacement hull single screw vessels. You can test this at slow (idle) speed by putting it in forward and noting the direction of turn...then put it in reverse and noting direction of backing turn....if it is opposite = torque. I teach new skippers how to u-turn a sailboat in close quarters utilizing this torque (walking the boat).
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    ๐Ÿ“ One more thing
    4 months ago by Cashrc ( Captain)
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    Oh..forgot to add that I can throw the rudder side to side, and sheโ€™ll rock side to side never changing course. Think Iโ€™m too light...( the boat, not me๐Ÿคฃ)
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    ๐Ÿ’ฌ Re: One more thing
    3 months ago by Cashrc ( Captain)
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    Hi Jonathan. Just reread your post about rudder area and possibly changing to twin rudders, I think your on to something. When I used to fly rc, I noticed that a plane with a larger rudder with less throw would turn tight with less drama than a plane with a small rudder at larger throws. I was thinking along the same lines as you..but one question. Should the rudder be deeper or wider?
    Cash
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by Griss ( Petty Officer 2nd Class)
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    Hello Toradog have you uploaded any photoโ€™s of your Elco P.T.
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by Cashrc ( Captain)
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    It looks like I can make a custom automatic dual rate for the PT. The Radiomasterโ€™s operating system is OpenTX. My buddy JP and I were discussing the PTs turning habits, and I told him about this post concerning the full size boats turning. JP is very familiar with what can and canโ€™t be done in OpenTX, and heโ€™s pretty sure itโ€™s possible to have an automatic dual rate thatโ€™s throttle controlled, i.e it will actuate past a certain throttle setting. Heโ€™s also reasonably sure I can set it up to have less throw to starboard than port once actuated. Stay tuned...
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by ToraDog ( Midshipman)
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    PS: You can find Jerry's complete post here: http://www.ptboatforum.com/cgi-bin/MB2/netboardr.cgi?fid=102...
    http://www.ptboatforum.com/cgi-bin/MB2/netboardr.cgi?fid=102&cid=101&tid=5004&pg=1&sc=20&x=0
    ๐Ÿ”—
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by ToraDog ( Midshipman)
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    Cash,
    I reached out to folks on the PT Forum and Gerry Gilmartin kindly responded with the following information and link.
    58ft Higgins for Dutch PT6 Port 368 Stbd 256
    Higgins 78 ft PT69 Port 336 Stbd 274
    77 foot Elco PT20 Port 432 Stbd 382
    Phila Navy Yards PT8 Port 443 Stbd 340

    Here is a video of PT658 in a HS turn you can watch: https://www.youtube.com/watch?v=aloAg5HAgHk

    As you can see by the video, they did not turn tight and the bow does not dive. All of the figures for turns are in yards, so the Higgins 78 turned to stbd in 274 yds, port in 336 yds. You should have no trouble scaling those figures to allow adjusting your rudder(s) throw. Now to measure out my ELCO! Good luck . I hope this helps.
    Jonathan
    https://www.youtube.com/watch?v=aloAg5HAgHk
    ๐Ÿ”—
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by Black Shoe ( Chief Petty Officer 1st Class)
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    To add to Toradog's comments, another detail is too much rudder angle is as bad as not enough. Anything over about 35 degrees of rudder throw begins to become a detriment leading to some of the symptoms you described. In most cases and tight quarters, max rudder (at 35 degrees) and a momentary increase in RPM may help a turn.
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by ToraDog ( Midshipman)
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    Cash,
    Going back and reading thru your build, I gather that you are running one shaft and rudder. Both the Higgins and the ELCO ran three shafts and rudders. of course all three props turned in the same direction, so turning was better in one direction over the other.
    I suspect that a lot of your issues are from the single rudder, which would not be huge by any stretch. I have seen folks build theirs with a single shaft and two or three rudders which gave good response to the helm without excessive rudder throw and thereby avoided the the snap roll you are experiencing. BYT nuclear subs suffer from the same effect when at speed and high amounts of rudder are ordered. Another reason that they like deeeep waters too play in.
    But I digress. If at all possible add two more rudders. This may not be practical without ripping the boat apart, been there, done that, don't encourage it, OR consider a slip on enlargement of the existing rudder that you can bolt into place for running. Removable for display it would leave only to small holes thru your rudder. increasing the surface area of the rudder will increase it's effect and allow you to limit your rudder throw, keeping you away from snap rolls.
    KISS principal. Just don't tell the cat.
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by Cashrc ( Captain)
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    Toradog, i think youโ€™re right. I did my best to keep my weight aft, all radio and power with the exception of the motor are in the aft 30/40 percent of the boat. She has no problems getting on plane in a straight line, but in a turn she tends to scrub her bow. Iโ€™m adding close to a pound of ballast just aft of the motor, it will be secured temporarily until I get her right. If I get her a little too aft heavy, Iโ€™ll go from 7 to 6 cells. I have plenty of power on tap so I can lose a cell and itโ€™ll just be a little slower. Balance first๐Ÿ‘
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    ๐Ÿ’ฌ Re: One more thing
    4 months ago by ToraDog ( Midshipman)
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    If you will allow me another comment. Pt's are sensitive to fore/aft weight distribution. It sounds like too much weight is forward. This would make the rudder less effective and cause digging in of the bow when in a hard turn. Remember that the rudder's action changes as the boat heels. The more off of vertical the rudder becomes, the more it tends to act as an elevator, lifting the stern and driving the bow downwards.
    My first suggestion it to carefully mark the scale waterline on the hull. 90% of the weight of the guts of the model should go as far back as possible, which usually entails putting you battery as far aft as possible. I digress... After carefully marking the waterline, distribute the guts in a way the makes everything accessible and safe, ie, in a potentially dry protected position.( sometimes easier said than done, but a receiver in a baggy is not a bad idea). Now place your build in a test tank( a bathtub works great if it will fit.) Move the guts around until you have a level waterline, fore/aft and side to side, remembering that the heaviest item should be almost at the transom.
    I would suggest aiming for straight line performance first. Easy to get onto plane, correct running attitude and reasonable response to the helm. If you can attain that, then work on your turning, remembering that she will turn like a single rudder destroyer(even when they had 3 rudders) except that you may find reducing throttle during a turn helps to balance your rudder input and reduce bow dive.
    I hope this helps. I am still learning and adjusting my 1/16th ELCO, but she runs better than I drive her.
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    ๐Ÿ“ Needs ballast
    4 months ago by Cashrc ( Captain)
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    Hi yโ€™all. Iโ€™ve been a bit busy with inventory so Iโ€™ll keep this brief. I maidened the Higgins this past Sunday, ran into 2 issues. One, she was way too light, which resulted in a hard to handle and trim boat. She weighed in at 4 pounds 2 ounces, thought I could run her at that weight but she was squirrelly, would turn to port okay, but right was shaky, and at one point instead of turning right she dug her bow in and and continued straight with a 40 degree list๐Ÿค”. What little water that got in the hull was from one of those escapades, and that sheโ€™d light on another problem. I had the receiver in the right rear corner of the hull, but low, as I wanted to make sure the servo wiring wouldnโ€™t be fouled by the rudder tiller. Sure enough, when she rolled hard right that tablespoon of water would collect there and get the receiver just wet enough to be intermittent. By the time I would get pushed in the receiver would dry out enough to regain control. My buddy Fred used his Vacuboat Vacutow and pushed me in 3 times!! I thinks heโ€™s sending me a bill for salvage๐Ÿคฃ๐Ÿคฃ Anyway, Iโ€™ve made a few changes in the servo/esc leads routing, moved the rx higher up in the hull and sprayed it down with corrosionX. Iโ€™ve also ballasted her to 5 pounds. Weโ€™ll see how she does.
    Cash
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    ๐Ÿ’ฌ Re: Needs ballast
    4 months ago by Cashrc ( Captain)
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    Hi Toradog. I usually mount my rxโ€™s high, but in this case I had it a bit too low because I didnโ€™t want to use an extension..๐Ÿค”. It wasnโ€™t on the floor, but the extreme roll helped it take a bath. Iโ€™ve fitted an extension and have it much higher up now...plus itโ€™s had a bath in CorrosionX.
    Cash
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    ๐Ÿ’ฌ Re: Needs ballast
    4 months ago by ToraDog ( Midshipman)
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    Well done!
    two comments. 1)PT's had a notoriously large turning radius, even the Higgins which had a tighter one than the ELCO. If too much rudder is applied, they lift their sterns and dig in the bow. My ELCO is notorious for that when I try to turn sharply. Solution is to reduce the rudder throw. 2) as a general rule, do not put the receiver in the lowest or low point of the hull, for the exact reason that you ran into, ie, shorting out the receiver. Rather, mount it high and safe( better radio reception as well there). To accomplish your needed routing of the servo lead, add an extension to it. Very inexpensive insurance.
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    ๐Ÿ’ฌ Re: Needs ballast
    4 months ago by RNinMunich ( Fleet Admiral)
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    Agreed Rowen,
    Plus the axial torque created by the rotating mass of motor, shaft and RH prop (flywheel effect), plus the force of the water shoved up under the hull by the rising prop blades!
    With a clockwise rotating prop (seen from behind when going ahead ๐Ÿ˜ฎ๐Ÿ™ˆ) the 'shove' would be on the underside of the port hull.
    Conversely, on the starboard side the blades are driving water down, away from the hull, creating suction. Both effects summate adding to the torque roll effect in light, fast boats with a single screw.
    Combined with the rudder 'elevator' effect you describe the boat could I suppose in an extreme case 'corkscrew' under! ๐Ÿ˜ฎ๐Ÿ˜ญ I guess you'd really really have to over motorise and fit a BIG rudder to actually push it under though - I hope!๐Ÿคž
    (Thinks๐Ÿ’ก might work on my U-25 though! ๐Ÿ˜)

    BTW Cash; on a more practical note - bilge keels might help ๐Ÿ‘
    But most of that problem is probably due to fitting only one drive train (motor, shaft, prop).
    Surely the Higgins PT boats, like the more numerous ELCO version, would have had three shafts? Thus helping to dampen the torque roll effect.
    Cheers, Doug ๐Ÿ˜Ž
    PS Curiously all the descriptions of the PTBs that I've read mention the 'high manoeuvrability', which doesn't quite gel with 'a notoriously large turning radius'!?
    PPS The angle at which you have set the prop shaft (relative to the horizontal WL at rest / keel line) might also contribute to a pitching effect over the CG/Centre of Buoyancy, thus pushing the bow down when thrust is applied. Combined with the other effects described it could well explain a bow over + list condition!? Pitch & Roll Man!!
    Real solution: fit three drive trains as in the originals (or at least two for balance). ๐Ÿ˜‰
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    ๐Ÿ’ฌ Re: Needs ballast
    4 months ago by Rowen ( Lieutenant Commander)
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    The tendancy to dig one side of the hull in on turns is caused by the propeller rotation as it pushes water against the turned rudder surface.
    It is particulary apparent on single screw installations as twins are usually contrarotating and counter each other.

    Although my Brave Borderer is triple screw it will do the same. Perhaps rather less noticably because the outer screws tend to even and damp the forces out.

    Not sure there is much you can do about it, I just reduce the centre screw rpm on RH turns.

    Ballasting the hull might help reduce skittishness. Would have guessed that model is typically around 6/7lbs weight. Never a problem for me as my models tend to be overweight anyway!
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    ๐Ÿ’ฌ Re: Needs ballast
    4 months ago by Ianh ( Commander)
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    Hi Cash
    I believe this is a problem with the Dumas kits of PT212 and 109
    Cheers
    Ian
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    ๐Ÿ“ Ready for the Pacific
    5 months ago by Cashrc ( Captain)
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    Hi yโ€™all. Paints done, guns are up and radios installed. Sheโ€™s ready to run as is. I have a few more details to do but Iโ€™m going to wait till the maidens done and I have her sorted out. Might be this coming Sunday, or the next. Sheโ€™s at 4 pounds 2 ounces, a little light but Iโ€™ll take some extra ballast with me.
    Cash
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    ๐Ÿ’ฌ Re: Ready for the Pacific
    5 months ago by Cashrc ( Captain)
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    Errolโ€™s a pretty big cat...he might get transferred to a destroyer๐Ÿ˜
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    ๐Ÿ’ฌ Re: Ready for the Pacific
    5 months ago by jbkiwi ( Fleet Admiral)
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    Nice job Cash, don't forget the video camera๐Ÿ˜Š

    JB
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    ๐Ÿ’ฌ Re: Ready for the Pacific
    5 months ago by RNinMunich ( Fleet Admiral)
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    A Mean Machine Man ๐Ÿ‘
    BRAVO ZULU Commander.
    ๐Ÿ˜Ž
    PS Once Lt. (Feline๐Ÿฑ) Errol gets aboard I don't think you'll need any more ballast!!
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    ๐Ÿ“ Paint!!
    5 months ago by Cashrc ( Captain)
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    Just a quick pic of the paint scheme on my PT. I started with a flat olive green and flat green, but they were a little too close in shade, so I took the flat green, added a bit of bright green and yellow, and shot some of the camo in that. Iโ€™ll add some black and details next.
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    ๐Ÿ’ฌ Re: Paint!!
    5 months ago by jbkiwi ( Fleet Admiral)
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    Looks good Cash๐Ÿ‘

    JB
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    ๐Ÿ“ Oerlikon gun and other things.
    5 months ago by Cashrc ( Captain)
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    Hi yโ€™all. The winter storm we had apparently put our dealership behind, so it has been decreed from on high that we are working Sunday๐Ÿ˜  sine the dealership was without power the first of the week, I did my best to keep the house, the girls and the cats warm. My wife agreed that today was a โ€œdaddyโ€ day, so I took advantage and got some more done on the PT.
    The aft Oerlikon gun is built up from metal castings and brass wire and tube. Only real spot that was really challenging was soldering on the shoulder supports so that they lined up. Thereโ€™s supposed to be a cast metal crank handle for the gun, but my kit had 2 ships wheels, so I modified one into a crank. I added 2 screws to help hold the assembly in place on the hatch, got the holes a little too close to the base so the scre heads wouldnโ€™t sit quite flush, so I Coates them with a little thick ca...Iโ€™ll add a little filler later and call it a rough weld๐Ÿ˜‚
    I also soldered up the aft guard that sits just fwd of the gun, and built up the ammo boxes using legos instead of the pine blocks that comes in the kit...just because I could.๐Ÿ˜€
    A couple of stanchions, the smoke generator and a few cleats and sheโ€™s ready for paint!!
    Cash
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    ๐Ÿ’ฌ Re: Oerlikon gun and other things.
    5 months ago by CaptLarry ( Chief Petty Officer 2nd Class)
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    Cash,
    The flux will clean a little as you solder, but it causes the solder to run where ever the flux flows to. A dry surface cleaned with Isopro will help you keep the solder where you want it.....experiment with it, and you will see that it takes less heat and solder for your application.
    Another thing that helps is to โ€œshockโ€ your iron tip each time before your next solder application. When it comes up to temperature, wipe the tip on a wet/damp sponge...this removes old flux residue and tired solder...gives you a fresh iron tip for a cleaner joint, and new solder flows smoother. Again, less heat and less solder.
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    ๐Ÿ’ฌ Re: Oerlikon gun and other things.
    5 months ago by Cashrc ( Captain)
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    Larry, I have a habit of just hitting the brass with StayBrite flux, the soldering it together. Probably if hadnโ€™t been so cold in the garage Iโ€™d done a neater job๐Ÿ˜‚.
    I never knew about cleaning the brass with alcohol, thanks for the tip!!
    Cash
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    ๐Ÿ’ฌ Re: Oerlikon gun and other things.
    5 months ago by CaptLarry ( Chief Petty Officer 2nd Class)
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    Cash,
    I was looking closely at your brass solder joints. Are you cleaning your brass tubing, and solder with isopropyl alcohol before you solder it together? It gets rid of oxidation, and makes a smoother solder joint.
    Just a hint...
    OW....PT lookinโ€™ good! ๐Ÿ‘
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    ๐Ÿ“ Did a little over the weekend
    5 months ago by Cashrc ( Captain)
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    Got a bit more done before the storm hit. I did the vents and gas caps, the fwd vents are used as is, the rearwar are lengthened with a bit of plastic tube and supported by a dowel glued inside..it extends from the tube about 1/4 inch and is glued into holes drilled in the deck. I did a dry fit of the cabin and torpedoes to see how sheโ€™s going to look.rear gun and few other details and itโ€™s time for paint!!
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    ๐Ÿ’ฌ Re: Did a little over the weekend
    5 months ago by Martin555 ( Fleet Admiral)
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    Good work Cash.
    coming along nicely.

    Martin555.
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    ๐Ÿ’ฌ Re: Did a little over the weekend
    5 months ago by jbkiwi ( Fleet Admiral)
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    Looking good Cash๐Ÿ‘

    JB
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    ๐Ÿ“ Baby itโ€™s cold....in the garage!!
    6 months ago by Cashrc ( Captain)
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    Hi yโ€™all. Itโ€™s been a bit, but Iโ€™m still plugging away. Between work, life and the weather Iโ€™ve been a bit too tired to do much, and as of now we are looking at 3-8 inches of snow, freezing drizzle and lows tomorrow in the single digits...which means my little ceramic space heater is doing good to take the edge off the chill in the garage. However, Iโ€™ve been able to make and install the hatches on the PT. These are simple parts made up of 1 and 2 mm abs and pvc sheet, handles are brass wire and the hinges are cut and sanded 1x4 mm strip abs. I have them built up and installed. I also built up a floor for radio and battery install.
    Cash
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    ๐Ÿ’ฌ Re: Baby itโ€™s cold....in the garage!!
    5 months ago by redpmg ( Commodore)
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    At least that's one thing we don't have Cash - that white stuff only appears on the distant mountains for a very short while. Having said that it was sweltering weather of mid 30c followed a day later by an icy front from the Antartic...........

    Detail coming along well as usual with your builds - good to watch ...........
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