Barrel Back….

[Paul TParticipant @pault84577]

Ashley

 

This motor is so powerful that it would work even if I fitted a 6in prop, mind you it would pull some amps.

 

Paul

[Bob Abell 2Participant @bobabell2]

Forgot to mention that the speedboat also had a stepped hull

 

Bob

[Paul TParticipant @pault84577]

Just ordered a 60mm brass prop from Cornwall Model Boats so I should be having some fun with the barrel back shortly.

 

Paul

[Phil Winks 1Participant @philwinks1]

They had my props with me the day after ordering Paul mind you I did order early in the day. excellent prices they have to. best of luck with it mate here’s hoping it goes well.

[Paul TParticipant @pault84577]

Hi Phil

 

They have a very good site with a huge range of products at good prices…..

 

If only they did free P&P…….then I would buy all my bits from them.

[Paul TParticipant @pault84577]

Here is a photo of the buisness end of the shaft, a bit tatty at the moment as it needs tidying up and polishing.

 

The prop is a 60mm 4 blade brass L/H unit with an M5 thread, the tube has a 10mm copper outer with a 6mm brass inner (one tube inside another for strength) the brass tube has a 5.4mm I/D.

The shaft is made from M5 stud bar (threaded rod)

The A strut is made from 6mm brass tube.

 

The U/V joint brings the prop into a more effective angle and I have allowed extra space between the prop and hull incase I wish to change the prop for a bigger one (max 90mm)

 

Paul

Edited By The Fat Controller on 22/06/2009 10:26:26

[ashley needhamParticipant @ashleyneedham69188]

Paul, a good solution. The picture belies the size of components. A brass ball and socket type of u/j would look a bit better methinks, but then more strain would be put on the A frame. Its odd, but on me MFA boat with the out-drive, all the propulsive forces act only on the hinged rudder/drive assembly, and the prop shaft is there merely to hold the shaft in position. i was, this morning, about to comment that your A frame didnt look to be braced sufficiently to contain the awesome forces of your motor, but in your case the prop shaft is also taking the strain,   Ashley

[Bob Abell 2Participant @bobabell2]

Hello Paul

 

How does your mechanism run?………Smooth or what?

 

I`ve seen a new type of coupling…(on the black and white boat posted earlier )…..as above but with an extra piece between the coupling halves……..it smoothes out the coupling action………worth a thought if you get in trouble?

 

Bob

[Phil Winks 1Participant @philwinks1]

Made by Graupner if memory servs Bob and priced about a quid dearer than the type you’ve used Paul available at CMB more slimline as well not sure how  robust but made by Graupner I guess they’re prob ok

[Paul TParticipant @pault84577]

Ashley

You do have a point about bracing the A frame as a quick test run in the bath showed the frame was binding on the shaft as the revs increased and the prop pushed at the frame.

 

Bob

The drive train runs quite smooth but I do see your how the new style coupling would help iron out any vibration.

 

You would not believe how much water ended up on the bathroom floor, the motor /prop combo is very effective.

 

Paul

[Paul TParticipant @pault84577]

Here is the removable motor in position, the 4 batteries will be placed either side of the motor (as shown) in the most effective position for the models trim.
It’s not as impressive as the strimmer engine and looks lost in the cavernous engine bay…I have to admit to being disappointed at the resulting image.

 

 

Paul 

[Bob Abell 2Participant @bobabell2]

How about an impressive “dummy” engine on top?……………with breathing holes of course

 

A vee twelve would be quite spectacular!

 

I`d paint the inside red too!

 

Bob

[Paul TParticipant @pault84577]

Bob

Oddly enough the history of this particular model goe’s back to when I was 10 and came across a Barrel Back when on holiday, it was powered by a V24 Merlin and I have been thinking of making dummy version to cover the electric motor.

 

Paul

[Bob Abell 2Participant @bobabell2]

So it was a sensible idea afterall!……….Youll soon get one made out of card and bits of this that and the other!

 

Bob

[Phil Winks 1Participant @philwinks1]

Paul the binding on the A frame may only be an issue on a static run I’m betting the stress will be a lot less when the boats moving. Know what you mean about the wet bathroom  floor had to mop ours when mine got tested.

[Paul TParticipant @pault84577]

Before Ashley gets back from work and jumps all over me I should edit my comment regarding the Merlin.

 

A Merlin is a V12 (not a V24) but this particular unit was an early 24litre model and not the typical 27litre as used in the Spitfire etc.

 

Paul

[Paul TParticipant @pault84577]

I have found that a local lake owned by the council doe’s not have a ban on I.C. engines even though the club that uses the lake does ban them.

So I am one happy bunny.

 

Should I fit the strimmer engine into the Barrel Back???

 

Paul   

[Phil Winks 1Participant @philwinks1]

Possibly Paul but I’d still be tempted to try the electric now you’ve fitted it. Also  I’m embarrassed too as a bit of an amateur plane buff I should have spotted the V24 Merlin gaff

[Paul TParticipant @pault84577]

Hi Phil

 

I might do what Bob suggested some weeks ago and make the engines interchangeable, the engineering involved will give me something to do for a few days.

 

Paul

[Dr John BoothParticipant @drjohnbooth43899]

Paul

Knowing you I presume that you have cleared everything with the council so I say fit the strimmer engine and enjoy yourself, life is just too short to worry about upsetting the resident model boat club, after all you have just as much right to sail your models as they do.

John

[Bob Abell 2Participant @bobabell2]

I`m sorry Dr John…………………….but to me, your advice seems,  for you, unusually irresponsible?

 

We can`t have a stranger like Paul, appearing at the pond with an IC powerboat……………….and simply flying round with total disregard for the host club?????

 

He wouldn`t last 5 mins!

 

Paul wouldn`t do that, I`m sure!

 

Bob

[Paul TParticipant @pault84577]

John / Bob

 

I wouldn’t sail on the club days which I believe are Tuesday and Sunday nor would I power around when other boaters were using the water as I have no wish to upset anyone.

I like to sail first thing in the morning and am usually done by 10am so I should be out of the way before the club members arrive.

 

John said that life is to short and I can see his point but I also believe in live and let live.

 

Paul

[Dr John BoothParticipant @drjohnbooth43899]

Hello Bob

 

Not irresponsible just direct and to the point.

Paul spends to much time trying to help others and seeing the “other point of view” he has cleared this with the council who own the lake and so he has just as much right to enjoy himself as anyone else.

I know that he wont charge around the water and risk any other models being hit nor will he sail when the club is using the water (even though he has every right to)

I also note that he has not revealed the location of the lake and I presume this is to prevent other “petrol heads” from flocking to the water and really spoiling it for the host club.

 

John 

[Bob Abell 2Participant @bobabell2]

Sorry John, I was a little hasty there?

But Paul will still need the electric version……………..For Birchwood!

 

Can`t understand why the club don`t use IC powered boats in the first place??…These ponds must be rarer than hen`s teeth!

 

Bob

[Paul TParticipant @pault84577]

Bob
Obviously I can’t speak for the resident club or why they took the decision to prohibit their members from using IC engines perhaps it has something to do with club insurance or maybe the members collectively decided to move away from using high powered IC as a means of propulsion.

 

Whatever the reason I can respect the decision and I will avoid using the barrel back during organised club sailing days or events.

 

I have also updated my insurance and specifically listed this lake as an active venue and submitted a detailed launching / sailing / recovery method statement and risk assessment to the council to satisfy their health and safety concerns.

Paul

Edited By The Fat Controller on 25/06/2009 06:59:29

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