By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Dremel

End point question

All Topics | Latest Posts

Search for:  in Thread Title in  
Neil Powell 121/07/2020 20:06:36
38 forum posts
3 photos

Hi,

I'm looking for a set of motors for my next project. On my last model i used a pair of mtroniks m600's which are rated at 12000rpm at 12v. As they were still too fast i set the end points on my transmitter to 30%. Am i right in saying that the motors will be limited to about 4000rpm?

Also has anyone got any experience of mfa metal gearboxes. Are they reliable and quiet?

Cheers

Neil

ashley needham21/07/2020 21:07:16
avatar
6611 forum posts
153 photos

Hi Neil.

What is the new project? We can’t even begin to advise you if we don’t know what it is,!

Size, weight, hull style, prop size, expected top speed etc etc

Ashley

Dave Milbourn21/07/2020 23:01:25
avatar
4003 forum posts
282 photos

Am i right in saying that the motors will be limited to about 4000rpm?

That presupposes that the ESCs are totally linear in response, whereas in my experience they seldom are. The only way to check is with a tachometer. You're better advised to fit slower motors or use less volts if you need less RPM because it's at the mid-speed range where ESCs get the most hot and bothered.

I've used the geared MFA motors and they most definitely are NOT quiet!

Dave M

Malcolm Frary22/07/2020 10:04:51
893 forum posts

ESCs run coolest at their extremes - fully off, no current, no heat. Fully on, no switching, just creating heat by virtue of component resistance. Anything in between, they are switching on and off several thousand times a second, and it is during the transition time between on and off that they create heat. If they can't get rid of the heat fast enough, they get hotter. And hotter, over time.

Having the right battery, motor and drive train is important. Getting round bad choices by bodging electronically is always second best. Going for a drastic end point reduction will likey result in rough control. Digital stuff works in steps. Closing the end point makes for fewer, but bigger, steps somewhere along the line.

Charles Oates22/07/2020 15:26:15
avatar
567 forum posts
46 photos

Hi Noel, I might have missed something, but if the model is being overpowered to such a drastic degree, why not just reduce the supply voltage from the 12volts you imply you are using, to 6volts?

Charles

Neil Powell 122/07/2020 17:40:49
38 forum posts
3 photos

Hi thanks for all the replay. My new model(bait boat) is pretty much a reworking of the last one with some improvements e.g better access to electrics. The size is the same but I'm hoping the weight will be slightly less. I have ordered a tachometer now from eBay so I'll be able to see how much rpm they are running at.

Learn something new everytime I ask a question on here. Never knew that esc's worked harder when in the middle range.

In respect of the suggestion that I use 6v batteries I want to stick with lipo to reduce the weight a bit, could go from 3s to 2s I suppose.

Dave Milbourn22/07/2020 18:05:21
avatar
4003 forum posts
282 photos

Neil

You haven't helped us to suggest motors etc for your next project. Please read Ashley's post again for the information we would need. Saying "it's pretty much a reworking of the last one with some improvements" doesn't get us any further along the path, m'duck.

Dropping from a 3S LiPo pack to a 2S will significantly reduce the motor speed but there's probably some much more suitable motors out there. I wouldn't look at an MTroniks 600 for powering a bait boat, but that's just my personal preference. Some anglers like their bait boats to run very fast to get the bait out there quickly, while others like to creep up slowly and deposit it carefully and precisely.

Dave M

Neil Powell 122/07/2020 18:22:06
38 forum posts
3 photos
Posted by Dave Milbourn on 22/07/2020 18:05:21:

Neil

You haven't helped us to suggest motors etc for your next project. Please read Ashley's post again for the information we would need. Saying "it's pretty much a reworking of the last one with some improvements" doesn't get us any further along the path, m'duck.

Dropping from a 3S LiPo pack to a 2S will significantly reduce the motor speed but there's probably some much more suitable motors out there. I wouldn't look at an MTroniks 600 for powering a bait boat, but that's just my personal preference. Some anglers like their bait boats to run very fast to get the bait out there quickly, while others like to creep up slowly and deposit it carefully and precisely.

Dave M

Fair point Dave. It will be a twin hull bait boat at 800mm long and 375mm wide. Each hull is 110mm wide. It is plywood construction and should come in at 6kg.

I believe that the mtronik m600's will be running at about 4000rpm and that works just fine on the old boat(same weight and dimensions) and leaves a little spare for when it's windy etc. The props are 50mm twin bladed plastic things on a 5mm shaft.

I was hoping to find a way of running the motors at 4000rpm ish without messing about with the end points. I know people are going to say throttle control but thats easier said than done when you are trying to manage the line on the reels and steer the boat at the same time.

I'm more of a slow and accurate type of bait boater. don't like all that white water coming out the back of the boat and it not really moving any faster.

Neil Powell 122/07/2020 18:29:33
38 forum posts
3 photos

img-20200721-wa0001.jpeg

Neil Powell 122/07/2020 18:30:32
38 forum posts
3 photos

img-20200721-wa0003.jpeg

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Boats? Use our magazine locator link to find your nearest stockist!

Find Model Boats!

Support Our Partners
Tony Green Steam
Premier March
Nylet
Sarik
Shrek
Restorers Wanted
Pendle Boilers
Shopping Partners
Social Media

'Like' us on Facebook

Follow us on Twitter

Pin us on Pinterest

Member Contributions
Distributors of Model Boats for our overseas readers
Highlights

Make sure you never miss out on the latest news, product reviews and competitions with our free RSS feed

Make your own contribution to the Website

We welcome well written contributions from Website members on almost any aspect of Model Boating with a particular emphasis on practical hints, tips, experience and builds.

In order to maintain a consistent standard and format, all suggestions should first be sent to me by Personal Message for approval in principle. Only a very limited amount of time is available for editing contributions into a suitable format for placing on the website so it is important that the material is well presented, lucid and free from obvious spelling errors. I think it goes without saying that contributions should be illustrated by appropriate photos. I shall be happy to give advice on this.

The Member Contribution area offers space for short informative mini articles which would not normally find a place in Model Boats magazine. It is an opportunity for Website Members to freely share their  expertise and experience but I am afraid that virtue is its own reward as there is no budget to offer more material recompense!

I look forward to receiving your suggestions.

Colin Bishop - Website Editor