Returning modeller

[James Hill 5Participant @jameshill5]

Thanks to a lot of help I finally managed to upload pictures. The error was totally my fault.

There are some patient people on this forum,

Many thanks,

Jim.

[James Hill 5Participant @jameshill5]

I`ve put the last three pictures in the album that I didn`t manage before.

In case anyone`s interested, the three crew members were originally from Tamiya formula one car kits from way back. The driver came from the J P S car , the navigator from the Tyrell kit and the engineer was given to me by a friend who knew I was looking for the one last figure. I don`t know his origins though.

Each of them has had major surgery on hands, legs, arms and in the case of the standing engineer, cut in half and re-shaped and stitched back together!!. I`m just finishing off his safety gear and deciding how I`m going to fix him down when we finally get to the water.

Jim.

[James Hill 5Participant @jameshill5]

I have had the misfortune to break one of the battery connectors in my Acoms transmitter.. It`s one of the flat sprung tabs for the negative end of the battery. With a bit of luck, I`ve managed to solder a piece of nickel silver strip as a replacement which appears to working.

My question is, can you get replacement tabs anywhere or would that mean binning the controller for a new one.? I ask in case my repair doesn`t last very long!

I`ve not taken the transmitter apart so I don`t know how things are connected inside. Just thought I`d ask the question,

Many thanks,

Jim.

[James Hill 5Participant @jameshill5]

I gave the boat a water test this evening with some success and some failure. Couldn`t see any leaks so that was the success.

The failure was under power, it managed to blow a ten amp fuse…. twice! so that terminated any more running.

Mtroniks suggested the fuse size so I am now looking at reducing the size of the prop.

Is there a way of working out an ideal size or is it a case of buying a smaller one and seeing what happens?

Many thanks,

Jim.

[Ray Wood 3Participant @raywood3]

Hi Jim,

Try a 35X prop and take the fuse out would be my advice, I've never used one in any of my boats.

Regards Ray

[James Hill 5Participant @jameshill5]

Hi Ray, I put the fuse in on the advice of the Mtroniks advice sheet that came with the ESC.. In my ignorance would the 35X prop relate to diameter.? ( the current prop being the only one I`ve bought so far ) and I`m still learning things in that department as I go along.

Thanks for your suggestion,

Jim.

[Malcolm FraryParticipant @malcolmfrary95515]

If a 10A fuse is being blown on a regular basis, it probably means that more current is being drawn than the 15A ESC can safely handle. A lower rating is needed for a fuse than the ESC involved because fuses are not instant acting. The length of high current time that it takes for a fuse to blow can be critical for the electronic bits involved. The answer is either a less demanding load on the motor (less prop diameter, typically) that will demand less current and/or a meatier ESC that can handle what is demanded.

A down and dirty method of figuring what ESC current rating is needed is to do empirical tests using fuses instead of an ESC. Fire it up under load (i.e. prop in water) and figure out the lowest value fuse that doesn't blow. Or use a meter to get the actual number, but most multimeters stop at 10A. Multiply that by 1.5, look for the next rating ESC above that figure. Avoid ESCs that claim 320A and don't have a recognised makers brand name.

[Ray Wood 3Participant @raywood3]

Hi Jim,

Yes the 35 is mm in diameter and the X is the pitch, they are black nylon material with a 4mm threaded boss, cheap as chip compared to brass props, SLEC sell them to support their range of boat kits.

How long is your Surfury? my 26" Cigarette bombs around on a 600 brushed motor, 15amp Mtronics & 7.2 Buggy battery. & weighs 3 lbs.

[James Hill 5Participant @jameshill5]

Sorry for the delay in answering, I had to go out this morning.

Malcolm, I understand what you were saying and I think the simplest thing to do, as you and Ray have suggested, is to reduce the prop size as a starting point and see how things progress.

Ray, thank you also for your similar suggestion. I weighed the boat just now with everything on board and it weighs in at 7.5 lbs, so it`s not quite a light weight. Apart from the boat itself, the next heavy bit is the battery, which is a 9.6 volt 5000mAh pack. The motor is a brushed Graupner 700Speed. I`ll have a look on the SLEC site for a prop. The prop I`ve just tried is a 43 mm plastic one by Octura. I`ve no idea what the pitch is. I bought it from a magazine advert back in the day without knowing anything about performance or power consumpton etc.

Your Cigarette looks the part. We used to go down to Swanage, on the cliff tops in the 1970`s, and watch the full size ones in the Cowes _Torquay- Cowes offshore races and they were impressive boats. Never saw Surfury race though, as it had stopped racing by then . I did go to the boat museum at Pitsea where it was on view , and took a load of photographs which I used when building the model.

Jim.

[James Hill 5Participant @jameshill5]

Forgot to mention. The model is 36ins long.

Jim.

[Ray Wood 3Participant @raywood3]

Hi Jim,

Yes if the hull is capable of taking an IC engine it probably is built like a brick outhouse I build light because electric doesn'nt need the strength generally, but I do have a 1/4"ply keel if it does hit something head on . I think a Surfury chugging round will be most disapointing, I would be tempted to get some HP from a brushless set up?

I love the detail in the cockpit BTW, my Cigarette design will be a free plan in Model Boats mag in the future.

Regards Ray

[James Hill 5Participant @jameshill5]

Hi Ray,

The original model was designed to take a 3.5cc diesel and I I`m sure that`s why the boat never got on the water as there was nowhere close I could sail it.

I then bought the prop with the intention of going electric ( possibly ). The problem I`ve now given myself is that the shaft is 3/16“ dia and I`ve made it with a dog drive which means there`s a lot of plain shaft at the stern. I`ve looked at carefully trying to cut a 4mm thread into it but I just think I`d end up with a bigger problem.

My next thought is to leave things as they are but get in touch with Mtroniks for a suggested change of ESC. If it runs like a canal barge then, as you say, I`ll have to start studying info on a brushless setup and that`s a whole new ball game for me. I`ll have another read of Mr Milbourn`s article.

The cockpit detail came from scaled down model aircraft decals, glued inside the rings and coated in varnish. The actual layout I copied as best I could from the boat itself.

Getting on the water is going to take longer than I thought and I`m certain I`ll be asking more questions if gets to brushless.

Many thanks,

Jim.

[James Hill 5Participant @jameshill5]

Evening all,

I`ve managed to post a few pictures of my T I D Tug that is now basically finished. I`ve finished hanging the tyres on the side and I`ve started to try and weather the boat.

As I said in an earlier blog, it`s powered by a 540 motor off a 6 volt lead acid battery. The gearbox I made myself (sorry, offhand I can`t remember the ratio ) .The prop is one I made and is 60mm, four blade but not sure of the pitch. The rudder and associated parts are all scratch built.

I built the boat from an MM plan and an article that was in a Model Boat magazine from 1974 but I`m not certain which month.

There was an article inside about the Tid Tug called " Cheap but not nasty " in which the author described how he built the model from various scrap bits and offcuts for a sum of six pounds if I remember correctly.

I`d love to find the magazine but so far no luck.

Jim.

[ashley needhamParticipant @ashleyneedham69188]

Jim. You can buy dog drive collets and stops enabling you to use dog drive props on plain shafts. I have successfully converted X props to dog drive by filing the cap end off, filing away the thread and filing two dog slots . Obviously you would need m5 props for conversion.

Besides those bits, your next purchase needs to be a wattmeter to stop the guessing regarding current draw.

Like Ray, hardly any of my boats have a fuse, however I know exactly how much current my motors take and use an appropriate esc. Really it is best practice to use a fuse…easy inserted in battery or a motor wire using 1/4 in female flat connectors and standard car blade fuses.

THEN stick it in the water! You are not that far from us at Bushy park, M3/A3 assuming you’re near Basingstoke. We would sort you out!

Ashley

Edited By ashley needham on 14/09/2020 08:32:41

[James Hill 5Participant @jameshill5]

Good morning Ashley and thank you for your reply,

Being away from modelling boats for so long meant I hadn`t realised all these bits and pieces for prop conversions could be had.

At the moment I`m waiting for a prop to arrive from the Prop Shop. I`ve dropped from 45mm to 37mm dia. as that was the smallest they did with a 3/16" dog drive that matched my system, so we`ll see how that fits.

The fuse that`s fitted is the same way you suggested and by Mtroniks. A bit cumbersome, but it`s all in there.

The next step is the bath test again and in the meantime I`ll look out for a wattmeter. I realise I`m going about things in a rather long winded way, simply step by step.

I live at Fleet and Basingstoke is about 10 miles or so from me, but if I end up in a real mess, I might take you up on your kind offer.

Many thanks,

Jim.

[Dave MilbournParticipant @davemilbourn48782]

Jim

This is the one I've been using for a long time now. You can download the manual to show you exactly what it will do. Established UK supplier, too! 4Max Budget Wattmeter

Dave M

[Colin BishopModerator @colinbishop34627]

Distance from Fleet to Bushy is just under 30 miles and 45 minutes according to the AA Route Planner so not too far.

Colin

[James Hill 5Participant @jameshill5]

Thank you Dave and Colin,

Dave , I`ve had a look at that link and that looks a nice piece of kit. I`ve downloaded the instructions as well. I take it this would be a permanent fixture in the boat or can it be swopped around? Sorry , I ask as I haven`t used one before. I need to do some tidying up of wires inside the hull. I left everything long at the moment to see how things went but it`s beginning to look like a vipers nest in there!

Colin, thank you for the mileage check. I`ll have look at the route.

Jim.

[ashley needhamParticipant @ashleyneedham69188]

Jim. It is just like using a multimeter but easier. It is used as and when, so is not fitted permanently.

However, and I have not looked, some of these things can be fitted and will record maximum values and checked on return to the shore to let you know what the boat is doing when in use..

Jim let us know if you plan a visit so we can bring appropriate gear and/or boats to help you.

Ashley

[James Hill 5Participant @jameshill5]

Thanks for that Ashley. I think I`ve seen on videos that some of those meters were on board which was why I was unsure.

If I can ever manage to get your way I would certainly pay a visit.

Jim.

[ashley needhamParticipant @ashleyneedham69188]

James, the time to visit is NOW before you put all the bits on!,

Ashley

[James Hill 5Participant @jameshill5]

Ashley ,

I`ve put three pictures on the album showing how things are situated in the model. As I said before, it needs tidying up, but at least I`ve had the prop turning, even though not for long. Still waiting the new one.

I had a look on google at Bushey Park. Looks very nice. At the moment a visit is a while away due to things being rather hectic at home at present.

Spending time knocking up a launch cradle to save bending the back!

Jim.

[James Hill 5Participant @jameshill5]

I`ve arrived at the stage where I now have a watt meter to do some checking with, but I have a couple of questions to ask. In the lower picture I`ve shown the wires as they are in the boat. Having never used a watt meter before would I be right in thinking that the section with the fuse and switch in it is removed and replaced with the meter using Tamiya connectors? The other thing that occured is by doing that, I remove the switch to the ESC or does that not matter.? The two sets of wires on the meter are12 AWG. Would that need different connectors at all when coupling to the existing setup?

Hopefully someone can point me in the right direction,

Many thanks,

Jim.

[James Hill 5Participant @jameshill5]

Having looked at my set up again and looking at suggested connections in the meter leaflet I`m thinking , If I put a male spade connector on the Red wires of the meter and bullet connectors on the black wires, leaving out the fuse ( for test purposes ) , the esc is still in use. To me, that seems ok., or is there a simpler way?

Thanks,

Jim.

[Malcolm FraryParticipant @malcolmfrary95515]

The important rule is that anything that passes power on should be shrouded and will probably be the receptical, any connection that collects power will be a blade. Same as domestic wiring – you dont want to be waving live power around where it can do harm. It doesn't matter whether it is the positive or negative side – it is whether voltage is being presented or collected.

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