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[Stavros]

Right then me slightly out of my Depth with regards to these Grey things!!!! Now I used to Have that overexcited MTB at the Mayhem bash that was powered by a MFA850 but was a bit greedy on the batt consumption side.At the moment I have fitted a temp motor yes an 850 but as I am  greedy sod and want longer running time BUT want the same power but less consuption so any Ideas chaps Will post some photos over weekend,you will be impressed I THINK


Stavros

[DaveB]

Stavros
My old mate Stan built the Perkasa and was recommended to use the Graupner 700bb on 12v he says she goes all right i'm not sure about run times i'll try to find out.
Dave

[Circlip]

Stavros! you CAN'T put a SMALLER motor in it  

[Powered Boat Mouldings]

Hi Stavros
             It has to be a Graupner 850bb turbo running 45 / 50 mm two blade prop at around 18 volts with 3000+mah metal hydride batteries. You should see about 20min, thats the price with big fast patrol craft. 

Regards Rob.

[Stavros]

Photos as promised

Stavros

[Martin13]

Stavros,

Nice build - very impressive

Martin

[Welsh_Druid]

Stavros had the thing going rather fast at the lake today - photos attached.

Don B.

[Stavros]

Hi Martin Thanks for that I must admit I did not build it my friend from Holyhead did. He regullary sells on Ebay under the name of Boatman Wales and he does do a cracking job on them.
Thanks for puting the piccies on Don

Stavros

[Powered Boat Mouldings]

Hi Stavros
             Loose the gel cells and she will fly

Regards Rob.

[Stavros]

yes seriously thinking and thats dangerous for me ,of putting 4x 7.2v buggy packs 2in series and 2 in parallel to give 14.4 v maybee then she will fly stuff the duration lets have some fun.Cos I fel the need for speed

Stavros

[HS93 (RIP)]

Putting buggy packs in  parallel is definitely  not recommended even if you have the best matched packs, my opinion

Peter

[Stavros]

ok why not

Stavros

[HS93 (RIP)]

even with matched cell packs they can discharge at different (internal Resistance) so as the packs discharge you can get a situation where one pack tries to charge the other.with modern cells this not the problem it was with the old nicads but it is still a problem , packs can vary quite a lot even if they are the same make and capacity and number of charges. if you are running two motors and two speed controllers have two separate 14.4 volt packs and there wont be a problem
peter

[Stavros]

Thanks for that HS93 but I am running a single motor,reason that I was thinking of this was to kep the old girl as light as I could,and get as much Amps as I could as the 850 draws an awfull lot of current

Stavros

[HS93 (RIP)]

for some reason I thought you where running two I just had another look at your pictures and it must of been the two batteries and I had brain fade . I had the same problem  a few years ago with a fire boat , I had to use nicads to get it to plane but at the time the best where 1800s and it had two 700bb in it I got one lap of the lake, and with the dry cells it would just plough and have a fantastic rooster tail.

Peter

[Powered Boat Mouldings]

Hi Stavros
              Use metal hydride batteries . They are now available at up to 4000mah . At last more power less weight.

Regards Rob.

[andyn]

Search online, can't remember where they came from but you can get 10,000Mah D size batteries from some model shop for quite a reasonable price. You would have to make the pack yourself though