Billing Smit Rotterdam motors

[John O’CParticipant @johnoc]

Looking for recommendations/advice

[John O’CParticipant @johnoc]

Hello Folks

Reading various articles on the forum I came across fuses!! Whoops forgot them in Scrappy!

This then led me to look at the future and the motors I bought with the Smit model. On enquiring on the J Perkins web site I find the JP Power 480 is turning at 17,000 rpm at 9.6 volt. I also purchased a 12v battery with the motors. Hmmm.

Steve Webb Models have offered to restock and I now need to find a suitable replacements to drive the 2 – 50mm 3 blade props supplied with the kit. (Assuming 50mm as they measure 25mm from centre to tip of blade)

Any advice welcome.

Cheers

John

[Malcolm FraryParticipant @malcolmfrary95515]

If you must run small fast motors with large props, a gear/pulley reduction is needed to fool the prop into thinking it is being driven by a larger diameter motor. Rule of thumb for direct drive – motor can diameter should not be smaller than the prop diameter. Rule of the other thumb – the motor should have more poles than the prop has blades. Gearing helps both.

[John O’CParticipant @johnoc]

Hi Malcolm

Thanks for the quick response.

Your thumbs give much better advice than Steve Webb Models.

The small fast motor, to me, is the problem hence my reqest for advice on the preferred motor or motor and gearbox arrangement. My question on gearbox's is do they cost energy wise and are they noisy?

John

[nomustangmarkParticipant @nomustangmark]

Hi John, a pair of these http://www.componentshop.co.uk/mabuchi-555-dc-motor.html on 12 volts will be perfect direct drive, no noisy gearboxes to worry about.

Mark..

[John O’CParticipant @johnoc]

Hi Mark

Just downloaded your Motor Performance XL file from 2010 and was going to respond to you. Went looking for the article that was discussed in the thread but didn't find it.

Motors ordered.

Many thanks.

Regards

John

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