Todays Boating

[Trevor HollowayParticipant @trevorholloway99134]

Having a bit of an experiment myself – latest incarnation using EDF power may be on the water on Sunday (weather permitting).

Ashley – latest modifications to the "other" experimental craft have been made prior to the new hull design.

[ashley needhamParticipant @ashleyneedham69188]

Good news. Look forward to that…a new hull…not bothering to mod the old one to test?

Have a band job afternoon Sunday, if I go it will be 9-11 ish.

[Trevor HollowayParticipant @trevorholloway99134]

Modified the old hull.

Unfortunately have just let the magic smoke out of an ESC from the resurrected project – will see what is in the "come in handy" box.

[NoelParticipant @noel26080]

Posted by Trevor Holloway on 07/12/2017 10:14:15:

let the magic smoke out of an ESC

LOL. Magic smoke. I did that with a battery pack when I allowed it's magic smoke to escape by cutting both battery wires at the same time, with the same tool.

Thinking about wetted area, I believe I have 2 options to improve performance on the EDF boat if the 64mm unit is inadequate:

1 Apply hydrophobic coating to hull, such as Rain-x.

2 Apply more volts. Have used a 3S battery on a 40A ESC so far, but sure 3.7v more won't hurt it. I hope.

[ashley needhamParticipant @ashleyneedham69188]

Noel. Don't think that the hydroponic coating will make a lot of difference, as a percentage.

Increasing volts will of course increase thrust and not the wetted area…ALTHOUGH with the extra thrust more lift might be gained cutting the wetted area.

Not much you can do with the basic hull, a new one would be needed. Any 40A ESC will take 12v no probs. Check motor to see if THAT will, but if it is brushless then it most def will take the extra.

Trevor has asked to borrow a model of something that I have, a pylon racer/tethered plane (only its not a plane, as such) to take measurements and so on from. Good stuff…used in conjunction with the fins from the Dragonfly??

Tackled propulsion on second project, project S. All glued in and had a quick test in the bath to make sure none of the joints leaked. WOW!! looking forward to this one! Wheres the mop?

Access to the insides on S is good barring of course the bits you REALLY need access to, like the rudder. To save hassle later on I will have to finish off the rudder bits and fit the tiller and then stick the deck on. There is finger access, but it would be tight. The deck will be stuck on with the hull upside down. Although the top of the hull is straight, it MAY not be 100% straight, and if I put the deck on a flat surface and then stick the hull to the deck, it will be absolutely flat and any small gaps can be filled easily. It is level side-side so no worries there.

HAve to visit the marina tomorrow and buy some marine grade silicone sealant to stick something in the boat. The marine stuff is an entirely different animal to the bathroom variety, much more gluey and sets a bit harder.

Ashley

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[Trevor HollowayParticipant @trevorholloway99134]

Looks like it will be chilly and windy down at the pond tomorrow so will probably just try out the modified racer then go home for a hot chocolate.

Ashley,

If I do not see you at the pond I will pick up the model, yes there will be hints of the Dragonfly incorporated albeit with "different" propulsion.

[ashley needhamParticipant @ashleyneedham69188]

Yes very chilly today, and lightly snowing as I type, or raining if not snowing!

No boating methinks.

Work on project V at a stop due to it being too cold in shed to be getting on with. Work on project S ongoing. I pop to the shed , cut or make something and bring it all inside to glue/mark up or whatever in the warm.

Google "grand tour Bond Bug"….now there's food for thought, although I could see that being very difficult to get right…speed…stability, awkward shape…driver (ESSENTIAL). Very cleverly modified AND it worked on the road. Must have cost a fortune. Broke world speed record for prototype amphibious vehicle or something at 47 mph.

Ashley

[Trevor HollowayParticipant @trevorholloway99134]

No boating – I thought you were dedicated / certified !

Took the modified racer out with promising results (admittedly only two loops) and yes the water was COLD.

Collected the items from Ashley – should be an interesting project, no idea if it will work though. Now I can do some measuring, cecking photos and sketching in the warm.

[ashley needhamParticipant @ashleyneedham69188]

Work on proj V has halted due to low temperatures in the shed, but that on proj S continues as it will fit on the dining table, aka interior workspace.

I have tested the propulsion (in the bath) and this works and does not leak. The marine silicone sealant is brill stuff, and has dried really firmly, the component(s) are quite immovable. On 9.6V the bath water was disturbed to the point of de-bathing the yellow ducks. Heaven forbid I should have to run it on only 7.2V (I don't think so).

Several items have had to be incorporated in the hull before the tricky business of applying the deck can begin, and I must not be impatient. Work on the superstructure is difficult mainly as I cant decide just how big to make certain things. I may do what I did for the Titanic, and make rough items to be placed on deck and then decide what I like the look of. Scaling up the pictures does not seem to working for me at the moment.

I have decided on the THIRD project now (the third to be made, NOT there's only one more!!!) and I am excited as although this will not be an uncommon craft, I think I have simplified it to the point where it couldn't get any more easy to make, yet still look like a kit. We will see, and only after proj S.

Going to have to decide on this years ice=breaker as well.

Ashley

[Trevor HollowayParticipant @trevorholloway99134]

Nice to hear the propulsion will be "sufficient" !

I have been busy placing orders for components ready for building one of the next watercraft, managed to find quite detailed drawings on the interweb so can work out the scale when the bits start arriving.

Ice breaking on the pond – hopefully will not burn out a motor this year.

[ashley needhamParticipant @ashleyneedham69188]

The propulsion was VERY sufficient, and MORE sufficient than I thought it might be. Previously tried on my 12 battery, the 9.6 was much better indicating the 12v one is past it. Heaven knows what it will go like on a 3s!!!

Next proj. Good stuff.

|Ah yes, ice breaking…I remember now!

Ashley

[Trevor HollowayParticipant @trevorholloway99134]

Disappointing trip to the pond,

Due to limited time I decided to only take one boat for trial after another modification leaving the tug behind.

Arrived to find 4-5mm of ice (only clear bit by the dock) and no other boaters. Turned round and came home for a hot chocolate.

I would not have had a go at breaking the ice on my own, great fun as it is the risk of getting stuck is too great.

[ashley needhamParticipant @ashleyneedham69188]

Well… I was down there about 9.25 ish. saw it was frozen,had a stroll round the pond and then saw Noel, with entourage.

​Yes caution when icebreaking. I think last year we had issues with the ice bending rudders (all that backwards and forwards motion with sheets of ice around)

​Made a master "bit" for proj S and have boxed this up ready to mix the silicone rubber ready for moulding two-off parts.
​Proportions of topside bits arrived at now, and a method of manufacturing the superstructure arrived at (in theory) to emulate the original. Hull now smoooooth, last lot of fine filler seems to be the last required…will dust with grey primer and leave to dry inside. Apart from painting and a small rudder skeggy thing the hull is almost done.

​Ashley

[NoelParticipant @noel26080]

Yes the ice was a swizz. Jet boat therefore continues to await first run.
Still it was interesting to see Ashley's project S and its very fine hull.

Kind of run out of boating jobs to do at moment until the jet boat has proven itself.

Did a few garden railway wagon refurbs and got on with painting the stationmasters cottage. First real railway stuff I've done this year as its been boats boats boats lately!

[ashley needhamParticipant @ashleyneedham69188]

Have not escaped the dreaded lurgy and have a streaming cold now. Has put a damper on the week before xmas I must say.

​Boating construction has mostly stopped apart from mixing up some silicon rubber goo to fill the little box up that will be a mould for something I want to cast in resin.

​On the basis that the silicone does not stick to much (as per the blurb) I have not greased the box so only hope it comes out ok. It also says de-gas thoroughly using a degassing chamber or de-gas after pouring to avoid entrapped air. Well. I don't have a degas chamber and the silicone looks like a mousse with all the air in it!!! but this should not make much difference to the small (turret) I plan to cast from this.

Ashley

[ashley needhamParticipant @ashleyneedham69188]

Well the old cold went from bad to worse and is only just showing signs of improvement, I will still not be fully fit for tomorrow.

Mould worked a treat. The silicone rubber is as stiff as a car tyre, but released the master ok. Two casts made.

Ashley

[peter ward 9Participant @peterward9]

well hope you are feeling better soon, almost everyone i know has had "the cold" this season unfortunately seems to take a time to completely shake off.

i guessed pond would have been frozen last week as when i looked out every thing was quite white with frost and from experience i know that it means that, being relatively shallow bushy freezes over very quickly

popped down this morning briefly and there was a gentleman that i dont think ive seen before but he knew of you, ashley, on this occassion he had a cornish gaff rigged sailing boat 1/10 th scal so a goog size and enough breeze to sail well

then noel came down with his EDF on a new light weigh hull, this is definitly the way forward for these units, it went very well and turned extreamley sharply when required , this is what i need for my own outfit, a drastic slimming class and light weight battery

hope to catch up with you in the new year best seasons wishes to and family

peter

[NoelParticipant @noel26080]

Thank you Peter – yes the EDF jet boat in the Rivos spare hull worked really well on its first outing. Nice and fast but very controllable. Even with just the inch or so of the rudder that is actually in the water, it turned with plenty of authority. Weight is about 890g all up with the battery. I can save a bit more my removing the redundant propshaft tube and motor mount that came fitted to the hull. Now I've just got to add a cockpit and cover the jet bit with some bodywork!

Landing craft had an outing with a tank squeezed which actually looked pretty good I think.

Merry Christmas!

Noel.

[ashley needhamParticipant @ashleyneedham69188]

Merry Christmas chaps. Just too lifeless to boat on Sunday. Glad to hear the EDF was a goer. Glad to hear the lander with tank looked good, its what they were built for (tanks).

Fiddling pathetically indoors on proj No2, armament sorted, still filling away on hull. Would have been finished in one warm summer week-end….but there we are.

​I need to get a servo now, make some funnels and the bridge, finish off the deck fittings and then cover up the lkjdfghiedhgif nhjkdsdkj under the hull and trim the sdfkjhsd evenly. Paint then.

Ashley

[harry smith 1Participant @harrysmith1]

Hi Ashley

Sorry about your cold, hope you are on the mend.

I had a flu shot for our winter (free for seniors).

I looks like a few of you are into EDF boating.

I had the idea a few years ago, but, was told they do not work well.

I drop the idea, but, I had a spare 24" ABS hull which had two little brush motors in it.

I have removed the motors , fix rudder(steering via motors) and crap radio system.

I think it would make a good test boat???

I have the plans of a tunnel boat with an old school brush motor and a stack of balsa given to me from a club member.

Also a spare small car ESC 60Amp and a 4S 1300mah Lipo battery.

May look at Banggood for a EDF???

Harry Smith

[ashley needhamParticipant @ashleyneedham69188]

Harry. My opinion is EDF craft need to be designed as such to work best. Look on them as low flying aircraft when they are working properly, but getting rid of the water drag is tricky. Obviously silly amounts of power will make anything work, but then a comventional prop drive will probably achieve better results for the energy expended.

Somethink like an EDF Bluebird would be fun, or any number of full size jet boat copies, or how about a Saunders Roe sea squirt,?
​Ashley.

[NoelParticipant @noel26080]

Harry – do it. I did it out of curiosity and because I chanced upon a cheap hull, but glad I did.
The EDF setup I've made is on a 24" Rivos hull, which is a light ABS moulding.
To recap, here's the picture:

It weighs around 860g with battery installed.
The EDF came off ebay from China but I see similar on banggood for about £13.
It is 64mm, 5 blade, with a 4500kv QX motor. I run this with a 1300mAh 3S lipo via a 40A ESC, which gives a bit of headroom for current. It is quite a hot motor, so this eats its way through 1.3Ah in a few minutes, but you don't have to be flat out all the time.

As alluded to a few posts back, this went very well – much better than I expected.

I think the key to their performance is lowish weight so the thing gets a chance to get up on the plane and realise the drop in friction you get when the wetted area decreases. The same EDF in my cruiser hull when I was testing it was quite lethargic – but that weighed nearly twice as much.
There is more weight to come off mine if I replace the "jet pipe" with thin plastic instead of that heavy cardboard.

[harry smith 1Participant @harrysmith1]

Hi Ashley

My EDF arrived today, 50mm 11 blade with a 60mm bell inlet.

850 grams on 4S, motor a 2627-4500kv.

On the scales hull 431 grams, 4S Lipo 130 grams and EDF, ESC, receiver and servo 194 grams.

I have a same looking rudder (61 grams).

The hull I copied into balsa skin one for my Hobbyking electric outboard ( 28mm 3000kv on 2S).

So I have a balance point to work from, also the hull was free!!!

I have the plans of the Wetjet which a nice gentleman (RAY WOOD) sent me and some free balsa wood for the build, but, the bottom for the hulls will be plywood.

Only three boats to finish first !!!

Harry Smith

[NoelParticipant @noel26080]

Posted by harry smith 1 on 29/12/2017 08:42:41:

My EDF arrived today, 50mm 11 blade with a 60mm bell inlet.

850 grams on 4S, motor a 2627-4500kv.

Should go well then.

[harry smith 1Participant @harrysmith1]

Hi Noel

I did read that tapering the jet pipe increases the thrust from the unit.

Harry

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