Motor /Controller /Prop upgrade

[ashley needhamParticipant @ashleyneedham69188]

Yes I had forgotten about the receiver batts. Indeed a win win situation,…replacement of a servo, bobs AND 4x batteries for the weight of one esc. Indeed if you went for an aircraft one, that might only weigh20gor so (fo

Know what you mean Ray, and that’s why I take at least two boats and a lander down on Sundays to give a good rotation of craft.

Ashley

Edited By ashley needham on 27/05/2020 10:41:01

[Dave Cooper 6Participant @davecooper6]

Hi Ray /Malcolm,

Yes, the Bob's Board does get in the way a bit, but, is part of the 'vintage' feel of the little craft. It does, however give a good progressive range of speeds if you keep the wiper /track clean… At the Tx end, the 'neutral' dead-spot is quite sensitive though and takes a bit of getting used to. I think this is where a programmable ESC would be nicer.

The Futaba packaging claim a BEC for the Rx and I power everything from the one Lipo. This may change when I have an Arduino on-board to control the gun turret ! (If I ever get that far…).

Yes Ray, the call of the wind is beckoning…

Dave C

[Dave Cooper 6Participant @davecooper6]

Posted by ashley needham on 26/05/2020 15:55:22:

Well done Dave. Ashley's doubts are still there and I didn't say it would not work, just that it would increase drag so a performance boost may be had by….

Not sure how you could fit a 3mm shaft if you have a 2mm already (without reading all the posts!!),

Prop choice is far greater for the standard 4mm shaft size, so that's what I would go for, and an S35 two blade plastic prop will do you. The easiest way to a bit more power would be to fit a 480 motor (J Perkins do one) which is the same diameter as a 380/400 and shares the same mounting holes, but is longer and a bit more powerful.

The "modern" alternative would be to go brushless but would mean a new motor AND a new esc. Personally a 4mm shaft, 35mm prop and 480 is the easy choice. Please replace the Bobs board with a Mtronics 20A ESC, which will do ok.

Should be able to upload the link.

Ashley

Regarding the link – I have a small number of videos (around 10-20 second duration) of yesterday's runs to add to a link. Would I need to 'host' these on Youtube first,for example, or, is there a facility via the "Album" ?

D

[Colin BishopModerator @colinbishop34627]

I'm afraid you will need to host them on You Tube. The Album on here only accepts jpegs.

Colin

[Dave Cooper 6Participant @davecooper6]

Thanks Colin,

I'll have a go at getting them on Youtube then….

Sorry about the duplication above – don't quite know what I did there ! Please feel free to remove one (or, both ?) of them.

Dave

[Malcolm FraryParticipant @malcolmfrary95515]

Mention was made earlier about the receiver having a BEC. The ones that I have seen were shy about actual information saying just what the BEC capabilities were. I suspect (and am open to correction) that the RX BEC just regulates the internal voltage within the RX to something that the RX is happy with, and does nothing for the rest of the system. Originally intended to simplify things in the days when 6 volt SLA and 6 cell 1.2AH NiCads were the state of the art.

This might well leave anything else plugged into the receiver running on full battery voltage, which might not be a good thing. Certainly not with things like Arduinos and the like. Many modern ESCs have a built-in BEC that supplies a regulated 5 volts dropped from the main battery voltage.

[Dave Cooper 6Participant @davecooper6]

Good point Malcolm.

On the box (outer) – 'Futaba Attack II 27MHz' – it just says "Battery Eliminator Circuitry". I think the original instructions (if there were any ) have been lost…

For the Arduino, I'll probably use the regulated 'on-board' 4.8 volt supply. This will do nav' lights, search light and gun turret etc. duties, together with in-series resistors as needed.

I think I will do some "low-voltage" bench testing though just to determine what the operational limits are. I have a feeling it will be 'jitter' (or, full throw) on the rudder servo and some erratic wiper movement on the BB – another good reason to exchange the BB for an ESC perhaps !

Regards,

Dave

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