Slo mo Shun

[Dave MilbournParticipant @davemilbourn48782]

 

Now then!………Have you actually had hands-on experience with a boat powered by 24 volts?………Any tips?

 

Not a five foot, twin-engined, three-point hydro – you’re a pathfinder here, matey. Just keep your fingers well out of the way…….

 

Any idea where the boat should balance on the bench?

 

See above!!

 

Ref charging time, I’d forgotten the cells are 4600mAH. There’s a simple formula for calculating the charge time. It’s Capacity in AH/Charge Rate in A x 1.4(ish). So 4.6/2 x 1.4 = 3.22, or 3 hours and fifteen minutes on the ANAFI scale. OK?

 

DM

 

 

[Phil Winks 1Participant @philwinks1]

Hi Bob in my humble (very Humble) opinion the simplest way to get a good starting point is to simply balance the vessel along its design water line (I trust that is on the billings plans) in a test tank?? or on the pond then open the taps very slowly and watch very closely. you’ll soon see if she wants to dig in or (hopefully) rise. Just watch for her rising to quick and if approaching waves throttle back just in case she’s too nose light. I’d be suprised if she gets on the plane much before 1/2 (.5) throttle and she ought to rise parralell ish to the water. If not simply slide your bty’s.

 

Just my 2p worth

[Bob Abell 2Participant @bobabell2]

Thank you, Dave and Phil

 

OK……What`s a ….ANAFI scale?

 

I know I shouldn`t be asking this……….I`ve led a very sheltered life!

 

Bob

[Dave MilbournParticipant @davemilbourn48782]

I know I shouldn`t be asking this……….I`ve led a very sheltered life!

 No, you shouldn’t………….but it means “As Near As Makes No Difference” (well, it does on the ANAFI scale……….).

DM

[ashley needhamParticipant @ashleyneedham69188]

Does the Slo-Mo HAVE a waterline as such?  i can understand,say, a trawler having a waterline to ballast to (as a model) but i would have thought that a speedboat would be as light as poss and have a notional waterline for aesthetic reasons only?

 

I have one I use…ANAICBB… As near as I can be bothered.

 

I have high standards, you know!

 

Ashley

[Bob Abell 2Participant @bobabell2]

Hello Ashley and Dave

 

Dave`s explanation doesn`t quite match his secret code………Must be something rude?

 

Ash……..There`s no waterline on the plan……..Not surprised really……….I`ll set the boat up, slightly tail heavy…………..AHFTB!

 

Went to the lakes yesterday…….AND WE GOT SNOWED OFF!……Is there no end to this winter?

 

Bob

[Phil Winks 1Participant @philwinks1]

Good point Bob and Naughty Dave  ok regards trimming I’d look to have a spot on the hull that should be level when at rest and trim it with a small spirit level in place ie: trim as near level as possible then if needed move the ballast aft a little bit at a time after each trial run/runs till perfection is achieved

 

And while we’re on rules  try using the TLAR (That Looks  About Right)

Edited By Phil Winks 1 on 02/03/2010 14:25:18

[Bob Abell 2Participant @bobabell2]

Thanks for your advice Phil

 

We did a round trip of 75 miles yesterday, to buy the battery charger PSU unit and the blinkin` shop closes on a Wednesday!…………Doh!

 

Now need to grease the prop shafts…………Got plenty of Vaseline, but will it do?

 

The prop shaft supplier reccos` just oil……..But I think the prop shaft is too easy in the bearings……..hence the mechanical noise…………..And a good dollop of grease will sort it out!

 

Bob

[Phil Winks 1Participant @philwinks1]

On the subject of grease ver oil in prop-shafts. there appear to be as many thoughts on this as there are modellers using them. personally I’m aware that to much Vaseline can bind the shaft causing a load on the drive train esp in cold water. (as if we ever sail in owt else) so I opt for light machine oil and rarely get anything up the stern tube esp in a fast vessel like yours the laws of hydro dynamics will cause a suction at the rear of the stern tubes sucking them dryer than the Gobi dessert

 

As for a 75 mile trip for a closed shop ! well how did the BT advert go “its good to talk” shouid’ve rung ahead mate and you can remind me I said that next time I do exactly what you did Wednesday lol

 

Phil shivering in the frozen north (well south Yorkshire to be precise)

[Bob Abell 2Participant @bobabell2]

Progress report

 

Made a bold start at charging the batteries this morning!……….One giant step etc!

 

Making very heavy weather at the moment!………The charger is far too Hi Tech for my liking……………..Got too many variable settings………..and the jargon is beyond me!

 

I charged two batteries today……..( Well I thought I had )…….3.5 hours each………Only to discover that the charger …….WAS NOT EVEN SWITCHED ON!!

Reading the small print, the Start button needs to be held for 3 seconds to start the process

 

So at this moment in time, progress has ground to a stop…………….and would you believe this!……………….the supplier does not accept phone calls!!!!!!!!!

 

Probably, just as well, as I wouldn`t be able to make sense of the advice anyway!

 

A truly sad state of affairs……………Sorry chaps………Bob

[Phil Winks 1Participant @philwinks1]

 and that’s my embarrassment Bob when we spoke about this on the phone it never occurred to me that the charge process wasn’t started Hell mate that was a schoolboy error on my part my only excuse is that mine starts on a momentary press and makes a very loud beep. Guess yours does to eventually. Still proves that you really have to go some to damage a bty with those chargers

 

Phil (off to the naughty step )

Edited By Phil Winks 1 on 12/03/2010 20:05:43

[Bob Abell 2Participant @bobabell2]

Thanks Phil

 

I`ll sort it out in the next few days………………….I`m being a bit extra cautious at the moment

 

There will come a time when I shall be thankful for the chargers cleverness and versitility!

 

In the meantime…… thanks for your expert advice on the phone, much appreciated, M8

 

Bob

[Phil Winks 1Participant @philwinks1]

No worries Bob one good turn etc  

[Bob Abell 2Participant @bobabell2]

Fear not, chaps………………Help is at hand……………..In the shape of the club`s resident LiPo/ brushless motor expert………………Graham!

 

A tentative date is set for next Tuesday morning, either to test run the boat, assuming I`ve made some technical progress or to go through the charging process….making notes as we go of course!

 

The good news will be that I can at least have a trial floatation test, to check for leaks and balance and get a few Brownie points along the way!

 

Whoopeeeeeeeeeeeeeee!……………………Bob

[Phil Winks 1Participant @philwinks1]

Thats all good news Bob, there’s nothing like having a hands on expert when dealing with new kit. Here’s hoping the tests run ok.

 

As an aside here’s a miniture copy of your rudders destined for  my 4hr challenge boat, the thread is in “all things floating” thanks for the inspiration

[Bob Abell 2Participant @bobabell2]

Think I`ve got this sussed now…………..Held the button down for 3 secs and all was revealed…………Charging at 2 amps and it`s counting down to completion……reading 14.5 volts

 

Note the fireproof stand ……….in the garage for safety

 

Happy again………Bob

[Bob Abell 2Participant @bobabell2]

Hello Phil

 

Just spotted your rudder design……………..Nice, but mine`s Ali!……………All that extra weight!….lo!

 

Keep up the good work………….Bob

[Phil Winks 1Participant @philwinks1]

Thats the way to go Bob you’ll either have a huge grin or be suicidal on tues lets hope its the former eh.

 

 

Phil (with his fingers crossed for ya)

[Phil Winks 1Participant @philwinks1]

hi Bob, the rudder is made from two laminations of .2mm brass sheet soldered along the edges makes for a stiff but light rudder probweighs about 2g I think I’d be struggling to get it that light and as strong in ali mate

[Bob Abell 2Participant @bobabell2]

Progress report

 

With great trepidation and hands a-trembling, I finally connected two sticks o` Dynamite…..( 24 volts )…….together…………and was surprised to find that the motor ran in a very similar manner to the 7,2 volt setup!……ie…….No fireworks!

 

Bit of a relief really…..Phew!………………….But it also could mean that the battertes are still not charged?

 

At the moment, the variable speed function is not working and I assume, the toggle switches need setting

 

Now pondering which combination I should try………………What do you reckon, Phil?

 

Bob

[Phil Winks 1Participant @philwinks1]

I’d seriously have a conversation with Dave Milbourne, Bob  as far as I can see those toggle (DIP) switches shouldn’t stop the throttle working all they do is alter the rate of control around stick centre and the top level avaiable. is your TX a computer one? if so is your throttle chanell end point (EPA) set to +/-100%  poss you also need to reverse the servo travel on the TX also I believe the trim should be set to +/- 0%. you could check the bty’s with a Multi meter but from what I’ve seen on here those bty’s are properly charged.

[Bob Abell 2Participant @bobabell2]

Thanks Phil

 

Dave wants peace and quiet on a Sunday………………..I`ll phone him tomorrow

 

I`ve tripped a few dip switches and your right, they only marginally vary the motor slightly

 

I`m quite happy the way these 24volt motors are running and the fan idea……..Is a complete success………………..The vents at the back are like afterburners!

 

So today…….We`re off to Llanberis for a day out

 

Bye………………..Bob

 

PS….Hold on a minute!……….It`s Mothers` Day!……….Trip cancelled………The kids will be calling!

 

Phew!…..That was a close call!

 

 

Edited By Bob Abell on 14/03/2010 09:41:06

[Bob Abell 2Participant @bobabell2]

Latest news

 

The sticks are regulating motor speed afterall………….It`s just that they start at a very high speed and go to a crazy lunatic speed!………………Time to consult the dip switch diagram…………Need to slow down the start-up speed drastically

 

If you are reading this Dave……..Forward and reverse is instant……..the interlock is not showing at the moment?

 

Anyway……..I`ve tamed the beast!

 

Bob

[Phil Winks 1Participant @philwinks1]

Just had a look at the DIP switch graphs Bob and as a starting point I’d go for this

 

sw1 on, sw2 on, sw3 off, sw4 on,

 

see how you go on the water with that then the options are

 

A: if the dead band around stick centre is to great set sw4 off.

B: if you feel ready for a little more top speed set sw3 on

 

I’m almost Jealous here mate you are going to have so much fun on Tue’s just hope your reactions are up to it  I reckon we’ll hear your shouts of delight here in somerset.

[Bob Abell 2Participant @bobabell2]

Thanks for the info, Phil

 

Unfortuneately, one of the P98`s is not working………Just constant speed all the time and no reaction from the TX stick……..This was the first one tested, hence my forum posting, but the other one is OK

 

The second P98 is working well, so if need be, I`ll be running on one engine on Tuesday

 

At the moment, the ESC is set with “No2 On”…….and seems OK to me……..I`ll find out more on sail day.

 

Like you said………All great fun in store!

 

Bob

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