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[frogman3]

HI Martin well them motors come today what you said try well they are some whoppers but i will see how i get on with them
cheers for the info
chrisb

[Akira]

Chris, I guess I do not understand why you are blowing 40 amp fuses. I run a pair of MFA 850 motors in my 1/48th Fletcher class and use a 25 amp fuse for protection for each motor. I have never blown it, YET, even with weed wrapped props. Neither the MFA 385, nor the 540's should come anywhere near close to blowing 40 amp fuses, even with two motors drawing thru the fuse. Given the size of you build, you should have plenty of power with four 540's which should not be drawing more than 2-3 amps, depending upon whether you are running 6 or 12 volt. 6 amps is a far cry from 40 so I would suspect that something is creating some serious drag on the shafts.
Please forgive me for being nosy, but if you disconnect your motors, can you EASILY spin each shaft with just two fingers? Spin the shaft, not the prop. If it takes any effort at all, there is any issue, as you are no doubt well aware.Good luck with you quest.
Jonathan

[frogman3]

Chris, I guess I do not understand why you are blowing 40 amp fuses. I run a pair of MFA 850 motors in my 1/48th Fletcher class and use a 25 amp fuse for protection for each motor. I have never blown it, YET, even with weed wrapped props. Neither the MFA 385, nor the 540's should come anywhere near close to blowing 40 amp fuses, even with two motors drawing thru the fuse. Given the size of you build, you should have plenty of power with four 540's which should not be drawing more than 2-3 amps, depending upon whether you are running 6 or 12 volt. 6 amps is a far cry from 40 so I would suspect that something is creating some serious drag on the shafts.
Please forgive me for being nosy, but if you disconnect your motors, can you EASILY spin each shaft with just two fingers? Spin the shaft, not the prop. If it takes any effort at all, there is any issue, as you are no doubt well aware.Good luck with you quest.
Jonathan

HI Johnathan no you not bein nosey at all as i appreciate any help from all you guys many thanks an yes i can easy spin all the shafts by hand that was not the prob but i cured that fuse blowin as it was a faulty motor in one motor circut that also supplyed the power from the ESC to the R/X an that caused everythng to have no power


 so as i said thats cured an she sailed abit last sunday but the motors i have fitted two 540 an two johnsons motors are just not powerfull enough as it was flank speed an tiger struggled to move accross the pond an the turn was terrible about 50 ft so im goin to make the rudder bigger


 an hopefully fit to more rudders on the outer props an fit new big props  an an i could not sail anymore to test her as the wind got up to galeforce an if i put her in the pond the wind would have blown her into the concrete pond edge so no more sailin an then to make matters worst


 as i was packin up i put all the S/S AWAY in their proteckive boxs but the wind was so strong that it blew the box off my chair onto the concrete an this was the front main S/S an caused a bit of damage but i can repair it thank goodness  an cant do any more on them big motors now as she is promised to go in a model show in october so after that then i will try an fit in the new bigger motors that martin recommened an then go from there but its always the case of alter one thing an a knock on affect happens so i may have to strip down tiger stern end an redo everything  anyway thanks for stoppin an hope you are well sir
chrisb

[frogman3]

HI ALL well been to model shop an bought some more bits to fit them big motors in tiger as the 540 wont hardly move her on the pond so i'll try these but its goin to be a whole lot of modifocation as im goin to try an fit twin rudders an maybe to rudders on her out board props so 4 rudders in all
https://ibb.co/whZWP6D    an im tryin to get some of these props as the props i have on are not big enough
so im goin for 45 mm diamiter an 4 mm shaft thread an 5 bladed two l/h an two r/h
https://ibb.co/nrhqbzB
chrisb

[Akira]

Hi Chris, I understand about the motor issue now. I am glad that it is not a shaft issue and hopefully the new motors will help.
My two Fletchers, both 1/48 and 7+ feet have single rudders. Both turn like the prototype, terribly!!!! I often find myself using throttles to help in the turns, especially when my eyes and depth perception fail me. That said, I might suggest using a rudder throttle mixer rather than messing with rudder size. I think that action makes one that folks have found to be reliable. Easy install too!Best of luck. I am waiting for the grand video.

Jonathan

[frogman3]

Hi Chris, I understand about the motor issue now. I am glad that it is not a shaft issue and hopefully the new motors will help.
My two Fletchers, both 1/48 and 7+ feet have single rudders. Both turn like the prototype, terribly!!!! I often find myself using throttles to help in the turns, especially when my eyes and depth perception fail me. That said, I might suggest using a rudder throttle mixer rather than messing with rudder size. I think that action makes one that folks have found to be reliable. Easy install too!Best of luck. I am waiting for the grand video.

Jonathan

HI AGAIN Jonathan well i treid a mixer on my USS NIMITZ 9ft carrier an it dint work very well im afraid to say so i went an fitted 4 ruders on her an she sailed great an turned quite quick which was a surprise to me an that why im goin to try an alter the rudders on my tiger but not goin to look nice but if it does the job to me thats all that matters as the ole mojo is now running low an a pic of my nimitz rudders
 https://ibb.co/qxx7FZs

[frogman3]

AN Jonathan a pic of my nimitz on the pond an she sailed very good
https://ibb.co/pb1BBP3
chrisb

[Rob47]

Hi Chris
I think you should play with the motors before adding rudders, although the single should do so not sure what going on.  Out of interest my Bristol which is nearly Tiger size runs on 2x MFA Torpedo 850, and she is responsive with those and turns nicely, the thing about having tad more power is she cruises sedately at scale speed and turns like a dream, if tighter turn needed forward one prop and astern the other.


Hope it is sorted as seems a shame, Phoebe/Hero now running, ready to fit deck, when found thread on starboard stabiliser had stripped, easy to fit with deck off but means waiting for the new one.


When are you sailing again? its Navy day at Kingscote MBC on Sunday so if storms have not washed them away a day out.




Bob

[frogman3]

For my 2p, I’d definitely go with 555 motors. I’ve had them in boats in the past drawing just a couple of amps on full bore

HI ALL you guys who said that the 555 motors would best well they are what i asked for at w/w an the chap said no they be to low a power an sold me them 540 motors which are badly underpowered so ive found on her last sail she was hardle movin so ive gone on what martin recomended an will try them thanks for all your advise guys
chrisb

[frogman3]

Hi Chris
I think you should play with the motors before adding rudders, although the single should do so not sure what going on.  Out of interest my Bristol which is nearly Tiger size runs on 2x MFA Torpedo 850, and she is responsive with those and turns nicely, the thing about having tad more power is she cruises sedately at scale speed and turns like a dream, if tighter turn needed forward one prop and astern the other.


Hope it is sorted as seems a shame, Phoebe/Hero now running, ready to fit deck, when found thread on starboard stabiliser had stripped, easy to fit with deck off but means waiting for the new one.


When are you sailing again? its Navy day at Kingscote MBC on Sunday so if storms have not washed them away a day out.




Bob

AN HI Bob well im not goin to sail her anymore this yr as im takin my norfolk an given myself a break from  tiger as ive got to try an fit in them new big motors an get some bigger props so she is in drydock for maybe 6 months if not longer if i have to drill out all 4 prop shafts an reset them oh dear but she is a very heavy ship an that little rudder just ain't up to the job so im fittin two rudders an its goin to involve a bit unsitely but needs must
chrisb
chrisb

[Martin (Admin)]

 
Super simple motor layout from Trucker's  Severn Supporter build ....



https://www.modelboatmayhem.co.uk/forum/index.php/topic,68655.msg752820.html#msg752820

[frogman3]

Super simple motor layout from Trucker's  Severn Supporter build ....



https://www.modelboatmayhem.co.uk/forum/index.php/topic,68655.msg752820.html#msg752820

HI Martin many thanks for the info and pic but I'm committed to the direct drive an with bigger props  but i do see what you mean sir as with your idea the motors can be placed in a different position an save having to drill out the prop shafts but i will see when i get round to doing it after the lowmex model show in October cheers sir
chrisb

[Rob47]

AN HI Bob well im not goin to sail her anymore this yr as im takin my norfolk an given myself a break from  tiger as ive got to try an fit in them new big motors an get some bigger props so she is in drydock for maybe 6 months if not longer if i have to drill out all 4 prop shafts an reset them oh dear but she is a very heavy ship an that little rudder just ain't up to the job so im fittin two rudders an its goin to involve a bit unsitely but needs must
chrisb
chrisb

Hi Chris, would not have said the rudder was small!!, I think because you are not getting the RPM from the motors you will not be getting a good flow over the rudder, hence poor turning, also if I recall all your props turn same way so that will not help.  Fit the motors first and give it a whirl, as a point Victorious which is nearly 5 foot has a rudder about 25x20mm and it turns lovley, because the motor has the power and rudder in line with prop.  Give it a try might save a lot of hassle and tears later.


Bob

[frogman3]

Hi Chris, would not have said the rudder was small!!, I think because you are not getting the RPM from the motors you will not be getting a good flow over the rudder, hence poor turning, also if I recall all your props turn same way so that will not help.  Fit the motors first and give it a whirl, as a point Victorious which is nearly 5 foot has a rudder about 25x20mm and it turns lovley, because the motor has the power and rudder in line with prop.  Give it a try might save a lot of hassle and tears later.


Bob

HI Bob no my props all turn inwards an not the same way dont know where you got that from sayin the props turn all the same way  an bob the rudder needs too be made bigger hence why im fittin two rudders an the props may hit the hull so i may have to drill the shafts out an reset them an i cant fit them big motors till ive found out about props but ive got to find somewhere to buy my bigger props as looked on cornwall model boats site but could not understand it to complex
ATB
Chrisb

[Rob47]

Hi Chris


Raboesch 40mm M4 Threaded 4 Blade L/H Brass C-Type Propeller RAB170-06 | Cornwall Model Boats
Hope that helps, not sure why you found it difficult, I typed that into search.
As for prop direction you told me that a long time ago :) :)


I don't think your plans for the rudder will make much difference to be honest, it has to be something else, as My Tiger ran on plan rudders, also asked a few other Tiger/Blake owners and they say same thing.
Good luck anyway but I really would try and sort the motors and run it once more.
Happy days today at the Navt Day sail at Knightscote, lovely weather and great water


Bob

[frogman3]

Or 4 of these at under a tenner each. 4800 revs, decent torque and low power drain.  https://www.componentshop.co.uk/mabuchi-555-dc-motor.html.html
I've a single one in a 12lb trawler with a 3 inch prop and it's got good pull from a standing start with a soft start ESC.

HI Tony  well when i went to wings an wheels i went to the components shop stand an was goin to buy these 555 motors an the chap said they would be too low power an recommened me to buy the MFA 540 X4  MOTORS an i fitted in just two an two jonsons motors they were no good an hardley moved tiger as she is a very heavy model so ive bought the one that martin reccomened so will try them an  some new bigger 45 mm props as cant go any bigger as the props will hit the hull so i may have to drill out all 4 prop shafts an reset them to take bigger props an cheers for this info
chrisb

[frogman3]

AN  HI ALL SORRY to ALL you guys who put info on here as i must have missed your posts as ive only just seen them regards motors
chrisb

[frogman3]

Hi Chris


Raboesch 40mm M4 Threaded 4 Blade L/H Brass C-Type Propeller RAB170-06 | Cornwall Model Boats
Hope that helps, not sure why you found it difficult, I typed that into search.
As for prop direction you told me that a long time ago :) :)


I don't think your plans for the rudder will make much difference to be honest, it has to be something else, as My Tiger ran on plan rudders, also asked a few other Tiger/Blake owners and they say same thing.
Good luck anyway but I really would try and sort the motors and run it once more.
Happy days today at the Navt Day sail at Knightscote, lovely weather and great water


Bob

AN HI  Bob sorry but  i dont want 4 bladed props as the real ship had 5 bladed props an could you please find out for me as i cant work that cornwall model boats site as my p/c is not goin properly as i live in a low megabyte area but could you find out for me how much these props are in linkpic below an 4mm thread an 45mm diamiter
cheers Bob
https://ibb.co/nrhqbzB
Chrisb

[tonyH]

Hi Chris, Just a thought regarding your headache. I noticed that the props from Raboesch have a pitch of under 1, i.e. they're not the most productive in using the torque/power at lower, non-racing, revs. It may help using a coarser pitch prop (>1) and experimenting before spending another £100 with cheap brass props and a pair of pliers or even cheap plastic ones. Could be worthwhile speaking to PropShop since they have a more precise knowledge and, for example, their standard 45mm 5 blader has a pitch of 48mm i.e >1
Sorry to introduce another variable
Tony

[Akira]

Allen, Off hand, it sounds like you need to do some programing in your transmitter. If you identify the model #, it will make it easier to help.Jonathan

[Rob47]

Chris
I was just showing you the site is ok, this is the nearest I could find and is the style for Tiger period




Raboesch 45mm M4 Threaded 5 Blade L/H Brass A-Type Propeller RAB148-08 | Cornwall Model Boats


Just a thought as it has not been mentioned, but are you getting sufficent rudder throw either side, as you dont mention if this large turning circle is in both directions


Bob

[frogman3]

Hi Chris, Just a thought regarding your headache. I noticed that the props from Raboesch have a pitch of under 1, i.e. they're not the most productive in using the torque/power at lower, non-racing, revs. It may help using a coarser pitch prop (>1) and experimenting before spending another £100 with cheap brass props and a pair of pliers or even cheap plastic ones. Could be worthwhile speaking to PropShop since they have a more precise knowledge and, for example, their standard 45mm 5 blader has a pitch of 48mm i.e >1
Sorry to introduce another variable
Tony

HI Tony so if understand you correctly you are sayin that them props
that i was goin to go are not very good then on thrust ? am i correct there ?
chrisb

[frogman3]

Chris
I was just showing you the site is ok, this is the nearest I could find and is the style for Tiger period




Raboesch 45mm M4 Threaded 5 Blade L/H Brass A-Type Propeller RAB148-08 | Cornwall Model Boats


Just a thought as it has not been mentioned, but are you getting sufficent rudder throw either side, as you dont mention if this large turning circle is in both directions


Bob

AN HI Bob yes the turning circle was terrible both  ways but the rudder goes full over an its got a futatbba 303 servo on it an quite powerfull  so if i dont cut the hull an fit two rudders then i need to make the rudder itself bigger yes?
cheers   has ive never had this probs before an i must admit im lost but im sure i need bigger to 45mm props an then i will try her with the motors that are fitted in with them bigger props if not still enough go then i'll fit them monster motors as i am tryin  to sort this but spending money but not gettin anywhere sorry guys to be a bug bear
cheers chrisb

[T888]

Hi Chris,




As Rob said, I would not add additional rudders just yet, I’d first change the motors and test them with the Five bladed props.


I’m surprised you were told the 555 motors were not suitable, USS Roosevelt is running on these motor and 50mm five bladed props and as you know she runs at a good scale speed.

[tonyH]

HI Tony so if understand you correctly you are sayin that them props
that i was goin to go are not very good then on thrust ? am i correct there ?
chrisb

Hi Chris, No I'm not saying that and I'm sorry if this is preaching but the angle that the blade cuts into the water has an effect on the push that the prop gives. So a shallow cut would normally be combined with a faster revving motor and a steep angle would combine with a slower revving motor. So a 45mm prop would have anything from a 40mm pitch to a 60 or 70mm pitch where the low pitch angle would suit a faster and the high angle would suit something like a steam engine. One of the main factors is the torque produced by the motor so if you have a fairly high torque motor like the 555 it will take a prop with a higher pitch angle while a standard 540 won't, even though the power could be the same. So check the torque rating for the motors you've got and see where they lie. The "C" type Raboesch props in Rob's earlier post have a shallower angle than the "A" type in his later one but even those could be a bit steeper, the normal scale type Prop-Shop ones being steeper still. Not a lot but. as I said, it could be worth talking with them.
Tony