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Author Topic: Shockwave 55 !  (Read 15551 times)

Biscuit

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Shockwave 55 !
« on: June 30, 2007, 06:32:19 PM »

Hi all,  as if I have not enough to do !
I could not resist this buy, at 200 for boat engine tuned pipe, new clutch, all the parts to make it into twin rudders. The guy I bought it off did not have time to do it, he was going to make into a surface drive like the new model. Not sure what way to go on this as it will mean ripping out the prop tube and getting a new one to come out the lower part of the transom, do you think it will be worth converting it? will do the twin riders but not sure about the drive set up. Got 2 flex drives with it and spare prop, all the radio, large rudder servo, need to make new engine mounts because of the clutch, but overall I think I got a bargain, any tips or info on the drive system will be most welcome, might hang on to the Puma as no one seems that interrested in it, and it is such a nice boat, and as for the Bluebird well still waiting for my alloy parts to be made, so on the back burner for a while.
Biscuit.
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Martin [Admin]

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Re: Shockwave 55 !
« Reply #1 on: June 30, 2007, 07:20:31 PM »


NICE!!!


If you don't post a video when it's finished... I'm ganna ban you from the forum!  ::)

Martin
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glennb2006

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Re: Shockwave 55 !
« Reply #2 on: June 30, 2007, 07:57:43 PM »

Correct - absolute bargain.

I would go most definitely go with surface drive. You will need a strut, a flex shaft and prop tube to go with it, Americans call them stuffing tubes. There are variations on the theme when it comes to the drive end. I run the strut that I got from Prestwich and have had no problems. Easily adjustable, not as easy as a stinger drive, but not too much trouble.

Sure that someone else here will chip in. Ian across in Sweden is very knowledgeable on these things and will be able to offer advice.

Also, Dave Marles, as I said, sells the lot. One thing you might want to consider is a silencer of some kind for that pipe though, they are noisy without.

Have fun.


Glenn

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Biscuit

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Re: Shockwave 55 !
« Reply #3 on: June 30, 2007, 08:32:57 PM »

Thanks all,
I will try my best Martin, think gas is the way to go! found a new lake so raring to go !! as for the surface drive, I have the flexi drive, the only thing that it is a bit long and will move the engine back so I cant get to the starter ! can you cut the cable and re-solder the end back on? and has the engine got to be in the same place as the original for the C/G ? The clutch has also meant that the motor has to go back even more, should I get the motor in the same place and then sort out the drive?? As to the pipe think you can get a little end can to go on it, can anyone help me out on this ? and what motor is this ? (so many questions) cheers guys
Steve.
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glennb2006

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Re: Shockwave 55 !
« Reply #4 on: July 01, 2007, 12:24:28 AM »

Hi there,

engine appears to be a Zenoah G230PUM, 23cc motor, never had one but also never heard anything bad about them. They can be tuned so as you probably have little history on it, you are not going to know until you run what kind of performance to expect. I have a 26cc version that is tuned to somewhere just over 7 BHP, and it goes quite well, I suspect you will not be disappointed.

Yes, you can get little silencers that fit over the stinger, they are not great but do take some of the "zing" off the exhaust note. It may be in the future if you like it and decide to keep this that you might want to consider something quieter, like a Prestwich pipe.

I think your carb is not standard.

As a rule of thumb, centre of gravity on the boat completed wants to be somewhere around 30 forward of the transom, so engine, clutch radio etc in rough position where they will be and move the motor fore and aft until you achieve this.

Cut the shaft to suit the motor position.

Petrol is quite convenient, chuck some in, pull the cord and you are away.

This boat should be quite quick when built, so you are going to need some space to run it in.

Have fun.

Glenn

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Biscuit

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Re: Shockwave 55 !
« Reply #5 on: July 01, 2007, 09:33:11 AM »

Thanks Glenn,
The flexi drive has a square on the end that goes into the collet of the engine, so was thinking as it is to long, to un solder the drive end near the prop and then cut it and resolder it, is that possible, or should I buy a shorter flexi drive? also got to sort out the engine mounts, not sure what they look like, mine are not long enough now the clutch is on there. Anyone got any links or pics of how the motor mounts fit with the clutch on the engine
Cheers
Steve.
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Biscuit

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Re: Shockwave 55 !
« Reply #6 on: July 01, 2007, 01:28:39 PM »

Ok Going with surface drive, cut out the old prop tube don't look pretty but a bit of filler will work wonders ! :) the old tube is steel with a Teflon liner, on my other boats the drive cable ran straight in the brass tube. Will this be ok ? as I have some brass tube left over from another build, this is 8mm o/d by 7mm I/d the flexi drive fits in the tube nice as its 6mm diameter or 1/4" . Can use those engine mounts, as the clutch has lugs on which I can M/C off then the engine mounts will make up the the thickness of the lug, if you know what i mean. This will enable me to keep the engine in the same place as it was, might have to move the tank as the pipe looks a bit close. ??? any thoughts on the way I am goingThanks
Steve.
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Re: Shockwave 55 !
« Reply #7 on: July 01, 2007, 02:51:04 PM »

hi
 why bother with  the clutch? if you fit it you will need a water pump to allow water to get to engine at tickover
                             steve
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glennb2006

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Re: Shockwave 55 !
« Reply #8 on: July 01, 2007, 05:09:26 PM »

Hi there,

picking up on what Steve said, I am not huge on clutches myself, if you do ditch the clutch you can fit a new collet straight to the motor, this can then be a round 1/4" drive collet, so this would enable the flex shaft to be cut at the drive end and refixed straight into the collet end. Actually, you can do this without ditching the clutch too.

http://www.prestwich.ndirect.co.uk/surfacedrive.htm

Have a look at the page on the link above for drive assmeblies, I am thinking SF2, 3 or 4 would suit you.

I have a round drive flexi shaft collet in the shed somewhere you can have if you want it, it came off a Zenoah PUM26, PM me your address if you want it and if I can put my hands on it I will chuck it into an envelope for you.

Notice you are at the holes in hulll stage, you might want to consider an additional and seperate water pickup for the engine or tuned pipe (manifold) cooling. I presume the maijn pickup is going to be in the rudder?
Also an auto bailer if you are going to fit one.....


Getting there though..


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Biscuit

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Re: Shockwave 55 !
« Reply #9 on: July 01, 2007, 06:17:54 PM »

Thought the clutch was a good Idea, why you not so keen? it is only going to tick over for  very short time cant relay see it getting that hot, seen a few boats that run an air cooled motors with just the pipe water cooled. Going back to the shafts will it be OK to run straight into the brass tube? as I said the other one had Teflon sleeve, think I will stick to the clutch and sure I can do some thing with the flexi drive I have, thanks for the offer and the link, may have to get a flex drive without that lump that the prop shaft slides into with the 2 grub screws. The water pickup is on the back of the rudder struts, 2 of them suppose I will have to link them up.
Thanks
Steve
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Biscuit

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Re: Shockwave 55 !
« Reply #10 on: July 01, 2007, 08:03:22 PM »

Ok Guys,
Promise this will be my last post today as the wife is feeling lonely, drilled the hole in the transom for the shaft and un soldered the end off the flexi drive, could I just make a longer strut bracket so I could still use it as in the photo ? it would be an easy option, the length from the transom to the prop drive dog would be 90mm. I know this would be spinning in the water but would it make any difference as it was like this when it was the standard set up  ??? ok thats it for today thanks for the info if you have any more on this set up drop me a line need all the help I can get thanks.
Steve
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glennb2006

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Re: Shockwave 55 !
« Reply #11 on: July 01, 2007, 08:05:41 PM »

Hi Steve,

And in response to yuor above, I replied while you were typing!

The ferrule can spin in the water OK, you are going to need to increase the distance from the transom to the drive dog some how to give you room to get the prop tube through the transom and leave clearance for the shaft. (they shorten when running on load, by 1/8" to 1/4" - leave 1/4" clearance. Also, make the hole through transom an elongated slot to allow up / down adjustment, and plug with somethiing flexible, like silicon,  to allow adjustment at the lake. Some leave a hole I believe.

the exhaust gets really hot, really quickly without water flow through it, which can cook the O rings. Normally keep the water feeds seperate, one to the motor and the other to the exhaust.

Some people use the ferrule system you have with no problems, I have never used one before.

Clutch just seems extra weight plus the traditional water pumps etc required. More to go wrong too. Does make it easy to launch the boat though.

The flex shaft should be fine direct in the brass tube with plenty of grease in it.

And some advice I gained (after fitting mine!!), bend the tube in a gentle "S", IE two bends rather than one longer sweep from end to end, stops the shaft whipping around so much.

Glenn



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Biscuit

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Re: Shockwave 55 !
« Reply #12 on: July 01, 2007, 10:56:15 PM »

I know I said it was my last post but managed to sneak on, Thanks Glenn, just what I wanted to hear ! I can make a new transom bracket and still get the clearance, will make an S bend like you said with a plywood brace underneath, then glass it all in. Yeah I like the Idea of the clutch, do I relay need the pump? hope to get motor in and shaft tomorrow.
Thanks.
Steve.
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w3bby

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Re: Shockwave 55 !
« Reply #13 on: July 02, 2007, 12:02:58 AM »

Looking good Steve. One thing I noted coming to this is that, from looking at your pictures, it appears you have a round collet at the motor already, so all you needed to do was cut the flex shaft to length. I hope that this will still be possible. If you have a square insert then all you need is a round insert to the collet.
Flex directly in the brass stuffing tube is what I have used in the past, as Glenn says some good waterproof grease in there and you will be fine.
If you do not intend to sit still and idle with the boat then a pump is not needed.

glennb2006

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Re: Shockwave 55 !
« Reply #14 on: July 02, 2007, 02:09:16 AM »

There you go Steve,  told you Ian would have some advice. Available for purchase are some very nice brackets that fit at the drive end and support the brass prop tube, they go between the 5" stringers to make a nice neat job of it.

Look at Ian's Sigma build thread to see what I mean. He has one there.

I have plywood in my current model, but my next one will have one fitted....

A couple of links that may be useful to you:

 http://www.americanrcboats.com/howto.htm
http://www.modelboatmayhem.co.uk/Forum_1.htm

Glenn.
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w3bby

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Re: Shockwave 55 !
« Reply #15 on: July 02, 2007, 07:54:24 AM »

T-bars are ok, it is the first time I have used one in the Sigma.
Moving on, the motor you have is a 230, this is the older 2-port motor. It is not as powerful as the modern 4-port motors but is a good motor to start with. You can do standard 2-stroke mods to them to get the power up but if and when you want more power a new Zenoah or Sikk motor would probably be a better choice  :)
The prop blast water pick up works OK I hear but have never used one. Those that I have seen tend to be placed at about 50% of the prop diameter at 1-2 o'clock seen from the rear. More important is to make sure the water outlet is visible so you can see if you have water or not when running. The pipe you have does not have o-rings I believe so you only need water to the head and exhaust flange, 1 pickup will do. Remember, water is in at the bottom and out at the top  ;)
Drive dog at 95 mm should be good, you will then need to make sure the rudders leading edge is about the same or further back. You do not need 2 rudders, one on the starboard side would do. It reduces the ability to turn left but generally is faster. I do not like rudders that have the pivot behind the leading edge but as this is a budget build who cares  ;D
The pipe you have is also OK but way too loud, you need to make or buy a silencer for it. There are pics and "how to's" on the net .
If you are going to use a square drive at the motor then the prop shaft and ferrule set up as you have it will be ok. If you are going to clamp the flex in a collet then you need to make sure that you have about 5-6mm between the strut and the drive dog. This allows for shrinkage in the flex as it winds up and shortens under power (as already stated by Glenn) and can bind/break  :(
You want to set this boat up with a CG of around 25-28% of hull length.

Biscuit

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Re: Shockwave 55 !
« Reply #16 on: July 02, 2007, 06:21:22 PM »

Thanks A lot of info there !
Could I put the 4 port barrel on the engine, say a 26cc, have done this on some of my 1/5 scale cars but maybe these were 4 port anyway. Been told that the 23cc motor is good in boats because it revs higher?? I normally just stick a 29cc big bore kit on my car motors, gives a massive increase in bottom power and still seems to rev its head off !, what is the best way to bend the prop tube in an S shape without putting a kink in it? has it got to be in an s shape as it would fit with just a shallow curve? as to the rudders I have 2 of them, and being a big kid at heart love the look of them so very tempted to fit em ! The new Shockwave has 2 rudders and 2 big servos, sure 1 high powered servo will be ok  ??? Trying to find the little silencer that goes on end of the pipe as dint want it noisy. Made the strut bracket today, all seems to line up fine, will have to cut the cable to size once the motor and tube are in, the C/G should be ok I think as the motor is back to where it was, there is just the added weight of the clutch but dint think this will be a problem. As to the hull, not going to spend loads of money on a paint job like I did on the Puma see how it goes first, spend the money on a better motor or running gear.  :)
Thanks everybody for your help, I am sorry but I will keep asking questions and posting pictures, as want to get this right !  :)
Steve.
Ps took the choke out today, and what do you think of the strut bracket and set up, thanks again.
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w3bby

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Re: Shockwave 55 !
« Reply #17 on: July 02, 2007, 06:52:37 PM »

Don't apologise!!! Pics are good, this is a nice thread for others thinking of going the same way. Nice brackets you made there ;D
No, you can't just throw a 26 jug on this, the ports don't match up. The 4-port car motor came a long time before the marine 4-port ::) There were guys in the USA doing hybrid conversions to get the 4-port advantage before the 231 came out. The 23 you heard as potentially revving higher is the 4-port engine, due to bigger transfers and lighter piston than the 26.
You can bend the prop tube by heating it to soften it (cherry and then air cool), putting the flex inside to stop it collapsing and then gentle pressure over your knee. When you have it as you want it, heat it again and quench in water. An S is said to give less drag and whip (2 bearing points) but a gentle curve will do, try and keep it straight 75-100 mm before the strut. You want about 15-20mm between the stuffing tube and the motor, no more or it could give you problems :(
Fun boat, you want 2 rudders, use 2 rudders ;D I would suggest a 1/4 scale servo (Hitec 705MG or similar) on a Y-lead and 6V for steering but I like meaty servos  ;D others use high torque standard size servos.
Painting the boat doesn't have to cost a lot, I use rattle cans and/or International yacht paint.

w3bby

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Re: Shockwave 55 !
« Reply #18 on: July 02, 2007, 07:16:57 PM »

Don't know if you are a member at Jims but try this link
http://www.jrcbd.com/showthread.php?t=3569&highlight=muffler
This describes using an internal stinger to reduce noise, how to make etc and on the pipe you have.
The alternative is to do something like this
http://www.jrcbd.com/photopost/data/544/mgilmanMidWCooper.jpg
like this
http://www.rocketcityracing.com/images/products/QDS.jpg
or like this
http://www.jrcbd.com/showthread.php?t=1905&highlight=muffler
Hope this helps with the noise issue ;D

Biscuit

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Re: Shockwave 55 !
« Reply #19 on: July 02, 2007, 07:25:44 PM »

Thanks for the thumbs up  :)

Got the motor in, can you have a look at the pictures at the drive line ? looks a nice gentle curve, would this be ok? and it would be very easy to put this slight bend in the tube. Must say a bit disappointed that its only a 2 port engine, but hoping that the surface drive will boost its performance  ??? still, seen a few motors on E-Bay that claim monster power figures, at very good prices but a bit sceptical  :o
Thanks
Biscuit
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Biscuit

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Re: Shockwave 55 !
« Reply #20 on: July 02, 2007, 08:47:13 PM »

OK its all in there, cut the cable, cut the tube and bent it to shape, it allmost runs flat along the bottom of the hull, left a small gap between Ferrel and transom, hope this is right  ???
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glennb2006

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Re: Shockwave 55 !
« Reply #21 on: July 03, 2007, 12:39:43 PM »

HI Steve,

looks OK, so long as there is approx 1/4" gap between ferrule and tube you should be OK. I shouldn't worry too much about the motor being 2 port just now, once running and set up you can then decide how to proceed, maybe some porting work to improve performance to start. The good thing with the Zenoah is that they share the same external dimensions so the 26cc motor should drop staright in at a later date should you so desire.

What are you planning on doing for a fuel tank for this one?

Glenn
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Biscuit

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Re: Shockwave 55 !
« Reply #22 on: July 03, 2007, 03:34:47 PM »

Thanks Glenn,
So I am going the right way then ? :) Hoping to get the tank along the side of the left hand motor rail, the radio box is going is going to be the big problem, the pipe is in the way, got a shallow radio box but got to get the rudder linkage out and up higher some how  ???  any Idea what kind of performance I am going to get out of this motor, as I feel I am doing all this work and going to end up with a slow boat, but like you said could always drop bigger motor in. well stuck with it now, so got to make the best of it. ;)
Steve.
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glennb2006

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Re: Shockwave 55 !
« Reply #24 on: July 04, 2007, 03:04:08 AM »

Aye,

you are right, the pipe over the top of the radio box is always a pain in the - well - painful things. Make the pipe run high enough you can get the lid off the back when needed.

I'm now watching the one Martin put the ebay link to, only ten miles from home.

Persevere as you are going, looks OK so far.

I would not have thought that you will be any way disappointed with the performance of this model when completed as is.

It should be quicker (a lot quicker) than your SC61 boat.

Glenn
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