Model Boat Mayhem
Mess Deck: General Section => Model Boating => Topic started by: merseyferry on June 17, 2015, 03:24:36 pm
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does anyone know were i can get the motor for a glasgow(graupner)the one with the little white gear thingy from .....thats my effort at being technical.. :embarrassed: regards paddy...
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Component shop....Maplins Steve's model boat bits Looks like a MFA 6:1 ratio motor.....it will tell you on the label
Dave
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thanks for that dave ill go have a look :-))
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Hi Paddy,
That's my Glasgow in the photograph from the Model Boats site. The steam was removed and replaced with electric drive. I used an MFA 919D 11:1 geared motor at 6v. The shafts are different diameter 6mm to 5mm and an adapter was bought from Technobots. Now the difficult bit, the 13T nylon gears are a Graupner product which is no longer available. The large gear is a Graupner 39T pinion, hence the ratio is 3:1 and all the calculations are explained in the Model Boats thread.
Due to the unavailability of the Graupner gears, look at an alternative drive system, plastic chain from W Hobbys has been successfully used by some builders and it's quieter than gears.
Tony
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Are they a strange tooth profile?
If they're a standard metric module, then you should be able to get a gear from somewhere like HPC gears. Won't be dirt cheap, but should do the job.
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thank you for your help guys ill,look into a chain linkage :-)) many thanks for the links also
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gday paddy,
I have used tooth belts in the past , 3:1 reduction ratio, HTD pitch , as MXL is a bit fine ,and possible to strip teeth off the belt.
work towards a final revs on paper , in the water , of 300/350 rpm, allow a little for slipage/load
try for a 545 motor , or 2+380/385
bill s
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thank you bill tony and sub ,ive decided a chain drive is the way to go,ive found this on ebay comes with a selection of difrent drive cogs being a table top modeler, i think it would work... what do you think as its the 1st time ive tried chain drive???
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Can you give the Ebay reference for these please as I am also interested.
Cheers
ken
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http://www.ebay.co.uk/itm/271374357824 (http://www.ebay.co.uk/itm/271374357824) ... there from france :-)) theres only 6 left
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Great. :-)) I clicked the reference title into UK Ebay and came up with some more in this country.
I need a system on my Seabex one, to join the pairs of motors together and this would fit the bill. What a handy and helpful forum this is. :}
cheers
ken
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happy to help kenny ,i hope itll drive the glasgow :} im thinking of a 540 motor like bill recomended
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I had a Glasgow. It does need gear reduction as the paddles must go slower than the motor. This is for more torque and a slower rotation. At least the Glasgow's wheels are on the same shaft.
The cog wheels supplied are all different sizes, so you have a choice of ratio's.
With me, I shall need extra packs of same size gears when making matching double wheels for my twin drives ...... a step up from rubber bands. %)
cheers
ken
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Hi Guys
I think I have a set of these. If I do, they're yours for the cost of postage (maybe not even that). I'll check in the morning and let you know.
Barrie
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Just checked - lots of chain, but only two gear wheels - approx 5.5 and 8 cms diameter. Drop me a PM if you are interested - I can email photos.
Barrie
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Merseyferry has first option, but if he doesn't want them, I will have them.
Very kind of you to let us know. :-))
Ken
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Sorry Ken - already had a PM from Merseyferry.
Barrie
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8) No problems. Very generous of you.
Anyone else have a sprockets and chain set up they don't want. :}
Cheers
ken
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Ken......what RPM and sprocket size do you intend to use this chain for?
Most small pitch Acetyl chain has an operation maximum surface speed of approx. 300 m per minute. <*<.......so from my solar powered abacus %) we see the examples....@ 3000 RPM
a 50 diameter sprocket = 3.14x50 = 157 x 3000 RPM = 471 m per minute
a 100 diameter sprocket = 3.14x100 = 314 x 3000 RPM = 942 m per minute
Although their example is a 10 tooth pinion = 28 diameter so
a 28 diameter pinion = 3.14x28 = 88 x 3000 RPM = 264 m per minute
Just examples to consider :o .....substitute your planned pinion/sprocket size & motor RPM................. Derek
PS...there is an engineering factor [number of teeth & ratio] that determines whether a chain wheel is called a pinion or a sprocket O0......
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Ken......what RPM and sprocket size do you intend to use this chain for?
Hi Derek,
Thank you for the all that information. I shall be digesting it as what you say makes sense.
It will be needed for my Schottle drive units in two formats.
(a) to join the dual steering into one servo
(b) to join the two prop drive shafts to one motor
The gear ratios are planned to be the same as motor speeds on both systems, therefore the rudder control will be gentle but the prop speeds will be at the normal speed of a motor yet to be chosen.
These speeds have been reported as bordering on destructive for the Schottle units, so I am a little concerned as to their sturdiness. I may have to use a reducing gear assembly to ensure they are not overrun to destruction.
I do appreciate your help and will be studying the data before committing to any design.
There are so many little features on this boat that are separate constructions now. My head hurts as I've just been out to look at today's work and realised so much needs to be done. I'm already beginning to notice things that I should have done another way !!
Sorry for side tracking your post merseyferry.
ken