Author Topic: MTB 488  (Read 8514 times)

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Offline AndyC

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MTB 488
« on: 04 April 2015, 14:17:05 »
New to forum and new to rc boating, hello all.

Having been into flying for some years , a change was on the cards. After some research the MTB 488 ticked all the boxes for me and after a call to Ron, a trip to Farcet I'm now the proud owner of a new kit.
Now coming from a electric flying background I'm naturally hoping to utilize my motors, lipos and esc's.
I'm aware of certain issues already , no reverse on esc,no cooling on motors/esc's, lipos may be lighter needing extra ballast etc.
Has anyone out there fitted out a MTB style craft on brushless.
My train of thought is guiding me to :-  increase volts =low current draw = low heat so with this in mind my motors are  around the 800kv spec, esc's are 60amp and my lipo is a 4s 5000mah.
This set up will happily shunt a 9lb mosquito round all day so a 6-7lb MTB with twin 35mm props should be a sinch?
Any thoughts /advise

Thanks
Andy

Offline colin

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Re: MTB 488
« Reply #1 on: 07 April 2015, 06:06:36 »
Hi Andy, and welcome...
your train of thoughts would be the same way as I would go about it...
you could go for a smaller prop and bring the RPM's up to match.. or even play with the RPM's to get the best deal..
some boats/ships work better on a smaller props than others, this also depends on the Pitch of the Prop, which is just the same as your are used to with your Flying background, the only difference is that Water is harder than Air..
this link could be an interesting read.. http://www.propellerworld.co.uk/Prop_Basics,_how_propellers_wor.html

there are Brushless ESC's on the market that do have a reverse.. which you could use at a later date..!
I would be inclined to use a in-runner, but then again if all the cables were neatly tucked away or cleated down, an out-runner does perform better..!

and by the way, enjoy your MTB build  ^^^


Andy Cross

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Re: MTB 488
« Reply #2 on: 07 April 2015, 16:42:42 »
Hi Colin,

Thanks for the reply and thoughts.
I've wondered how a prop pulling through the air compares to pulling through water. Your comment makes sense.
I think i might try a test rig set up using the components from the kit and see what amps are being generated against the pull from the rig in the bath. I'm aiming for half or less from each component rating , ie , motors pulling 30amps or less, esc's 30amps or less and the lipo, 40amps or less.

Should be fun.
And yes, i'm thoroughly enjoying my MTB so far.


Andy

Offline AndyC

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Re: MTB 488
« Reply #3 on: 08 April 2015, 18:38:06 »
Hi Colin,

Thanks for the reply, i was wondering how water and compare when pushing/pulling props. Looks like I'll doing some testing in the bath first before hitting the ponds. :smiley1:

Thanks
Andy

Offline AndyC

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Re: MTB 488
« Reply #4 on: 09 April 2015, 18:49:42 »
Does anyone know where or how I can down load a copy of the review done on this boat back in 2007 in the dutch kwiklink magazine


Thanks
Andy

Offline colin

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Re: MTB 488
« Reply #5 on: 10 April 2015, 07:33:23 »
not to sure were you could get the article from ..!
I only know that the name has changed to .. http://www.modelbouw-aktueel.nl/
and that an article was in these issues of the Magazine..!!
http://www.magazineexchange.co.uk/modelbouw-aktueel-magazine-issue-114-2006.html
http://www.magazineexchange.co.uk/modelbouw-aktueel-magazine-issue-115-2007.html
http://www.magazineexchange.co.uk/modelbouw-aktueel-magazine-issue-116-2007.html

hope this might help you, or point you in the direction needed..  8)



Offline subdriver

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Re: MTB 488
« Reply #6 on: 12 November 2015, 21:21:59 »
Hi Andy,

I might just be a few month to late ... but if you want the articles just send me a PM with your E-mail, i'll send them to you. (I'm the one who wrote them.) Part 1 and 2 are even translated into Englisch, part 3 partial.

https://www.youtube.com/watch?v=ymEKzY2giYk

The 488 still is my favorite fast scale model!
« Last Edit: 12 November 2015, 21:24:58 by subdriver »