Thor

[Paul TParticipant @pault84577]

The towing post is made

The pumps have arrived, and just for Bob here is a photo showing all of the major equipment with a ruler so he can judge the sizes.

Showing pumps and motors in position

Another view of the pump compartment.

Paul

Edited By Paul T on 23/07/2014 14:01:04

[Bob Abell 2Participant @bobabell2]

Welcome back to the forum, Paul, your technical presence has been sorely missed! We trust you are feeling better now?

Nice to see all the gear nicely laid out for our inspection

How about a sketch of your latest swivelling thrust nozzles?…..I wouldn't have thought swivelling nozzles are really necessary?

Your model looks very nice and very businesslike

See the note by Cookie asking about Brutus at the Haydock Show

Bob

[Bob Abell 2Participant @bobabell2]

Sorry to report that Paul is still out of action

We wish Paul all the best and hope he gets back on his feet ASAP

Bob and forum friends

[Paul TParticipant @pault84577]

Thanks Bob

Out of action is very apt. If I don't improve soon I doubt that I will see Haydock this year.

Paul

[curlyParticipant @curly]

Hi Paul

I'm sorry to hear your not well, hope you get better soon.

Dave

[mike farrellParticipant @mikefarrell21522]

Hi Paul Sorry to hear you have been unwell and hope you will get to Haydock .. No wonder the boat is so big ,with all the hardwear you will need all the space . The Enchanted Hammer (Thor) is developing very well after a misshap which is now rectified

90 mm props difficult to get but will find them .Offered some from America but postage prohibitive. All the electrics on site ESPs on order

PM sent

Michael

[Bob Abell 2Participant @bobabell2]

Come on, Mike

Post a few pix of your build……and make Paul happy?

Bob

[ashley needhamParticipant @ashleyneedham69188]

Paul you have to get well to finish this baby off. Interesting with all the hardware and funny props. Needs lots battery power. Ashley

[Paul TParticipant @pault84577]

Hi Curly

Thank you for the kind words

Hi Mike

You could try 85mm to 95mm props

I am in the process of moving the thrusters outlets to under the hull so that they can swivel to provide additional forward or reverse thrust. The trouble is that, as you have seen with your model, I am fast running out of space and having to design some very exotic plumbing.

Hi Ashley

I am ordering a 12v 26a/h golf trolley battery which will provide both power and ballast.

Paul

 

Edited By Paul T on 23/07/2014 19:48:56

[Colin BishopModerator @colinbishop34627]

Just take things easy Paul. Your health comes first!

Hope you are feeling a bit better.

Colin

[Peter FitnessParticipant @peterfitness34857]

Yes indeed, Paul, as Colin says, your health is paramount, and I too hope you are feeling better.

Peter.

[Bob Abell 2Participant @bobabell2]

Hello Paul

Hope you are feeling better this morning?

Don`t want to put a downer on your Thor project, but aren`t we over stretching ourselves here?

How are you going to pick it up?………I guess the all up weight to be about 80lb!

It`s a sobering thought?

Bob

[Paul TParticipant @pault84577]

Dear All

Thank you for all of your get well messages, they are very much appreciated. 

Hello Bob

Feeling a little better today but I am tanked up on tramadol so I am feeling no pain.

The all up weight will be around the 80lb mark and even though I intend to add things like batteries and ballast after the model is launched it will still be something of a problem getting the dry model into the water.

I will either use a launching trolley (where there is a suitable slipway) or a combination trolley and mechanical lifting / launching device.

The mass of the model is the downside to having a really powerful tug.

At the moment my desk is full of pumps and plumbing fittings as I design my way out of the swivelling thruster problem, the critical rotating elbows have arrived so I can start playing with real equipment rather than just drawing the solutions.

Paul

 

Edited By Paul T on 24/07/2014 12:41:54

[CookieOldParticipant @cookieold]

Hi Paul , Your health comes first ,if you don,t make Haydock there will be plenty more times for me to see the Beast Brutus and meet yourself.

Very Best Regards Dave ( cookie)

[Paul TParticipant @pault84577]

Hi Dave

I am under the best care in the world, Jane only lets me do so much and then makes me stop before I fall over.

However it will take something really serious to prevent me displaying at Haydock. Arthur and Jean who organise the event have bent over backwards to make it easier for me, Arthur has placed me right by one of the doors and arranged for assistance to help me off load and move my boats and Jean has secured a disabled pass for my car so I don't have to walk any distance.

Given how much this dedicated couple have to do in organising this event I am extremely grateful that they have found the time to help me.

I am looking forward to meeting you and all of the other forum members.

Dave am I right in assuming that you were in REME?

Paul

Edited By Paul T on 24/07/2014 13:43:11

[Andy CParticipant @andyc56856]

Hi Paul

Glad to hear you are on the mend and it sounds like you are in goods hands. Careful with that Tramadol, awful stuff. I was on it for a while, felt no pain but mostly felt not much of anything. Sent me doolally.

Cheers

Andy

[Paul TParticipant @pault84577]

Hi Andy

I know what you mean….they do turn your head into cotton wool.

Dear All

As the medication has turned my brain to mush I have a conundrum for you to solve.

Thor has 4 swivelling thrusters mounted on the bottom of the hull each of which has to rotate through 180deg.

I have decided that the motive power for all of these will be a single motor driving a threaded shaft, the threaded shaft allows the sliders to move horizontally up and down the threaded shaft.

My problem is transferring the horizontal 'up and down' movement to the 180deg rotational movement of the thrusters.

The drawing shows the equipment layout and the various direction of motion.

Any ideas?

Paul

[Bob Abell 2Participant @bobabell2]

Hello Paul

One suggestion would be to fix two worms to the central drive shaft and each nozzle be fitted with a wormwheel or even spur gears

Hope you can understand that?

Bob

[Bob Abell 2Participant @bobabell2]

Another idea….

Fix a chain sprocket to each nozzle and connect them with a periphery chain

Fit a motor and sprocket for rotation

I prefer this idea

Bob

[Gareth JonesParticipant @garethjones79649]

Hi Paul,

I was about to suggest something similar to Bob's idea. However I don't really understand what sort of 'control laws' you want to appy to the nozzles. Presumably you want to be able to use both pumps on one side to move sideways, one on each side to rotate the boat about a vertical axis, all four aft to supplement forward thrust and all 4 forward for reverse. By the time you have got all those functions combined with moving the nozzles it's going to be an awfully complicated control system.

It seems to me it would be much simpler just having the nozzles inside the hull pointing outwards as shown in the diagram and using the main motors and propellers for forward and reverse. That way you can keep all the pipework inside the hull and don't have the drag of the nozzles sticking out underneath. You can use differential control of the main motors to supplement the 'yaw' control (especially if you have twin throttle transmitter sticks like Bob.)

Gareth

 

Edited By Gareth Jones on 24/07/2014 18:59:45

[Gareth JonesParticipant @garethjones79649]

Here's my variation on Bob's chain and sprocket drive. However I still think by the time you have mechanised all this and got 4 rotating nozzles sealed to prevent water ingress to the hull it's more trouble than its worth.

Gareth

[Bob Abell 2Participant @bobabell2]

Gareth

I propose one chain around the outside of the two sprockets and a drive sprocket anywhere on the inside

Two sets will be required

Or a drive sprocket to each nozzle for real versatility!

 

Bob

Edited By Bob Abell on 24/07/2014 20:22:02

[Paul TParticipant @pault84577]

Hi Bob

Thanks for the suggestions, I do understand and your comments are in line with my somewhat addled thoughts.

Hi Gareth

Thank you for taking the time to do a drawing and for the helpful comments, regarding it being more trouble than its worth….I agree but every so often I set myself a difficult (and sometimes pointless) task simply to keep the old grey matter working.

Paul

[Dave MilbournParticipant @davemilbourn48782]

Paul

I'm wondering where all of these swivelling nozzles etc are leading. In my simple world thrusters are fixed and point sideways at 90° to the keel, and any change in the speed of the vessel either ahead or astern is done with the main engines.

The options seem to be either "spin", where the bow thruster pushes the bow to starboard and the stern thruster pushes the stern to post (or vice versa) – thus making the model spin about a vertical axis; or "slew", where both thrusters push in the same direction and make the model slew sideways.

With a few cunningly-placed Schottky diodes you can do all of that with one P94 connected to the four pumps. There's no need to resort to swivelling nozzles which could well be an absolute nightmare to operate with the model on the water. See Fig#8 on Page 3 of the illustrations in the P94 Manual here **LINK**

Sorry to chuck a Spaniard into the works…………….

[Paul TParticipant @pault84577]

Dave

I started off with the intention of simply enabling the model to move sideways but got carried away with the notion of 'crab steering' and harnessing the extra oomph that the thrusters will provide when towing.

John would have appreciated the finesse of the concept.

Paul

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