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Author Topic: KING OF SHAVES STEERING problem  (Read 6748 times)

Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #25 on: September 27, 2016, 08:12:32 PM »

 Mart I have removed the tube from the hull, 11mm i.D. which was made from a thick wall aluminium this meant my tube needed an additional outer tube to make up the difference. This was alright because it gave extra support in the hull. I had spoken to a Coppersmith friend who told me after softening the brass tube, block off the end with a wood dowel then to fill the tube with fine dry sand (See pic 018) compress it and after sealing the end off, the thin wall tube can be bent without the tube diameter being distorted. This I did and the bent tube now lines up between the hull and skeg. (see pics) I thought you meant to retain the teflon liner and I have put it inside the new brass tube, The skeg has two bearings inside and with the wall being thick enough (on the skeg) I have been able to bore it out to suit the new  tube. Now I have got it lined up and needs fixing in the hull (pic 021). What started out as minor mod has turned into big overhaul, but should cover for any shaft problems.
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #26 on: September 27, 2016, 09:18:43 PM »

Looks a lot better than it was mate ,usually we only use thin walled brass but at least yours will be a lot stronger than it was so its all good  :D .
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #27 on: September 28, 2016, 09:53:31 PM »

The shaft assembly has now been fibre glassed inside the hull and on the outside the tube has been profiled with P38. The skeg end has enough movement to allow for adjustment of the prop angle. With this section nearly complete I can now go back to the rudder arrangement. I have got the new higher torque servo now and with a heavier gauge push rod it should make a difference. When I had the three rudders linked together, I think the servo must have stalled and been ineffective with the water pressure.
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #28 on: September 29, 2016, 06:52:10 AM »

Nice job  :-)) one thing i notice is you dont have much of a gap between drive dog and strut,you need at least 1/8" to allow for cable shrinkage  under load when using a round collet that grips the shaft .Also at the other end put a small zip tie round the flex between tube and collet and trim it off this will save your shaft and prop in case the collet ever lets go.
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #29 on: September 29, 2016, 11:02:58 AM »

Thanks Mart that is good point, I will make sure I leave a gap between the Drive dog and strut. On this shaft arrangement the prop shaft has a shoulder which would prevent it coming out of the strut and if the flex drive came loose at the drive end it should be recoverable. When I take the flex out I have to take the prop assembly and strut off and draw the flex out of the tube, then I can dismantle the the prop drive dog etc.
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #30 on: September 29, 2016, 03:52:02 PM »

Sounds like it was originally set up for a square ended flex and collet  with those you dont need the gap as the flex floats if you get me .If using the round collet that grips the flex then the gap is needed or else things bind up and thats when things can get ugly .
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #31 on: September 29, 2016, 09:10:54 PM »

I do not know what the original assembly arrangement was, but like you mentioned the early flex drives on the electric boats I came across used the square ended flex and did float in the squared socket end of the drive shaft. I have taken a photo of the dismantled assembly on this boat and you can see the flex shaft 6mm is brazed to the 6mm stub shaft which is then stepped down to the 5mm section of the shaft which is the i/D of the two internal bearings. I understood the original prop was two bladed and had a bore to suit  the stub shaft 5mm. The three bladed prop I have on has a 6mm I/D and has a brass tube distance piece. when assembled. I will still make sure the flex shaft has clearance between collet and the strut body which should allow it to move
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #32 on: September 29, 2016, 09:16:50 PM »

If it were me id do away with that strut and shaft and get a new 1/4 "flex cable with welded shaft with drive dog but thats just me  :} .Id get a skegged strut too as that will also help the cat in the turns.
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #33 on: September 30, 2016, 10:46:51 AM »

If I have to change the present drive arrangement i would go for the system you have. I did have a similar arrangement on another boat and the weld failed on the joint and I lost the stub shaft and propeller. The replacement shaft (See photo) is loose in the strut and the plain bearing? must have failed? and together with the strut will need replacing. If the joint fails on the present system on the flex to stub shaft I will still have the prop.
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #34 on: September 30, 2016, 04:32:37 PM »

Back on the steering, the radio box with the new steering servo is back in the hull and fitted with a 2.65mm dia push rod. The push rod connection on the rudder arm had to be changed to take the push rod dia. The steering system is rigid now and I do not think it will flex under load.
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #35 on: November 17, 2016, 08:18:36 PM »

October-November, I have had a number of runs now with the new set up and the boat turns a lot better to the right as expected. As suggested the main problem was the servo, lack of kg thrust. I also had cooling problems I cracked the cylinder block through lack of coolant and had to replace the barrel, the piston etc was ok.  I have now replaced the single water supply rudder with a double one and separated the water jacket and manifold to two individual supplies which now leave the side of the hull where I can observe them.
 Attached pictures show the improved turn.
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MichaelRanger

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Re: KING OF SHAVES STEERING problem
« Reply #36 on: November 17, 2016, 08:36:05 PM »


Well done Dave,


You are now making good progress gradually sorting out the issues as they develop.
Keep going in the right direction but make sure that you keep the engine cool enough.


Regards,


Michael
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #37 on: November 20, 2016, 10:58:11 AM »

Hi Dave sorry Ive not been around lately had a few health issues going on and a lot of boats to build so its been hectic .Good to hear the steering is now sorted.
As regards your cooling setup be sure to go in at the bottom of the cylinder and out the top this avoids getting any air which will create a hot spot and cause big problems.
I always use separate cooling for the motor and the exhaust,i go in the cylinder and out into the cooling flange then out of the boat and the tuned pipe is completely separate .
Mart
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #38 on: November 24, 2016, 07:00:23 PM »

I have been using the supply from the rudder to supply separately the water jacket and the manifold, the vertical transom tube to supply the tuned pipe. On the water on the right hand turns no water comes out until the boat is on the straight, I have now tried to extend and modify the rear supply tube as per picture and use this supply for the water jacket and use the two supplies from the rudder for the manifold and the exhaust pipe. (these connections as you mentioned Mart to the lower input stubs).
I also found the hull difficult to handle (15" wide and 6" deep) and is awkward  to transport, I had a stand made of plastic tube but this came apart and i accidentally let the boat fall. Now making use of a light weight luggage folding trolley and a old walking frame I have now a have trolley/stand which I can store the hull in the upright position. The pictures show the basic parts, the finished trolley with protected pipe insulation and the use of thick cushion foam on the end, the boat on the trolley and also in the vertical position.   

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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #39 on: November 25, 2016, 11:07:42 AM »

Im looking at that pickup tube and thinking thats going to cause lots of drag and could effect handling ?.I only ever use the rudder pickups on my boats,sometimes i open the holes a tad and always use large diam tubing 4 mm int diam  not sure what your using now mate .
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w3bby

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Re: KING OF SHAVES STEERING problem
« Reply #40 on: November 25, 2016, 01:26:04 PM »

I use a round file to extend the inlet holes on the rudder right up to the leading edge.

Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #41 on: November 25, 2016, 06:54:55 PM »

I have been using 4mm bore tubing, but I had not thought of opening up the lead holes on the rudder, a good idea.
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john mantova

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Re: KING OF SHAVES STEERING problem
« Reply #42 on: November 29, 2016, 04:40:58 AM »

You could extend the hull back to reduce the length of the step it needs to be about 1/2 the length/ I did this on a boat that wouldn't plane  but it did afterwards . Good luck John
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #43 on: November 29, 2016, 12:26:30 PM »

John,


Do you mean add trim tabs? the hull appears to plane alright the prop angle makes a big difference to the way the hull planes.
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john mantova

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Re: KING OF SHAVES STEERING problem
« Reply #44 on: December 03, 2016, 12:48:25 AM »

I meant build the bottom further back.  But no matter if all OK  {-)
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Dave J

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Re: KING OF SHAVES STEERING problem
« Reply #45 on: December 22, 2016, 07:56:20 PM »

With the changes to the water pick up, I have had a few good runs on the lake the spray made the water outlets difficult to see clearly but the engine appeared to be cool enough. Then I hit a submerged item, (a branch may be?) the rudder was kicked back but I was able to bring the boat back to the jetty. I re-positioned the rudder and re launched the boat after half a lap the power became reduced and the boat stopped. When I eventually got it back to the bank I noticed the engine was still very hot-- no cooling, I had not examined my curved inlet when I hit the submerged item only the rudder. (the tube had bent back kinked the tube which closed the water supply off) The cylinder barrel was cracked and had to be replaced. As previously suggested I have opened out the two holes in the rudder which now supplies the water jacket and manifold. The curved water inlet has been replaced with the original straight tube. I have had a run today with the rebuilt engine and looks good for further sailing when the weather improves (bitterly cold and windy today)
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martno1fan

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Re: KING OF SHAVES STEERING problem
« Reply #46 on: December 24, 2016, 08:33:55 AM »

Sorry to hear about your mishap  :D ,regarding your cooling the two in the rudder should be enough,i use one for the motor and header then out and the other just cools the pipe . Merry Christmas  ;)
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