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[Stuw]

I had thought about turnbuckles too and read about spokes recently. All after buying the M2 rod!


I plan to spray the outside but brush the inside. I’m in a warm garage but won’t spray in there so will have to do it outside when weather is suitable! Still a long way to go to that point.


My SLEC order arrived with all sorts of goodies including 12mm ply for the motor mount braces. Will try to make some real headway next week on all fronts! Days are getting longer and the sun is shining here!


Whilst I think about it, do you have any sort of o ring or seal on the rudder to stop water coming into the stern via the post? I didn’t seem to have and was going to use lithium grease to help block it? My rudder sits in a fairly tall tube.

[zooma]

I use a lithium grease on my rudder shaft to stop water creeping up the tube and to keep it lubricated.

Although I have not had any water come in this way - I have had to remove the rudder tube and seal it back into the hull with Araldite  - not a bad idea in any case as it is another barrier between the water and the wood to stop any water creeping into the wooden keel and causing the plywood to delaminate in the longer term.

[zooma]

The postman arrived with a 12" M5 prop shaft this morning so I cut a 6mm wide skeg to form a fillet between the shaft and the keel and after double checking my measurements I marked the area of the shaft where it passes through the keel and roughed-up the outside of the tube and glued it into the hull with 24hr Araldite.

As a reference, Rapier1 performs really well with a forward positioned (non kit standard) prop and rudder position so I wanted to do something similar on the Javelin as it uses exactly the same hull.

Rapier1 has its prop shaft tube ending 7" from the transom and the rudder shaft is positioned 4" from the transom.

By shortening the prop shaft to 12", this Javelin has its prop shaft tube ending a little closer to the transom than Rapier1 at 6 3/8", but the rudder shaft will be mounted at the same distance of 4" from the transom.  The prop shaft has a nice shallow angle that still gives 1/2" clearance between the tip of an X50 propeller and the bottom of the hull on the centre of the keel line and has almost zero over-hang past the bulkhead into the engine bay.

Note:-  All of the measurements used in the description above for use on this Classic model boat are given in "time appropriate" inches - not those new fangled milli-centimetre thingies.

I noticed a rudder (old type with brass tube and blue plastic tiller arm) being auctioned on eBay with all funds going to a good cause so I placed a bid and ended-up winning it for £9.70 including postage.  I am quite pleased about this as I am not too impressed with the plastic moulded mounting shaft type that we now have as a universal offering from most (if not all?) suppliers, so at least one of my current projects will end up with a decent "old style" rudder mounting.

There is also a chance that I may be able to clean-up the brass rudder mounting tube that was buried in the filler paste and epoxied and glass fibre resin laminated into the inside of this Javelin hull.  This took quite a bit of time and effort to get it out and it did not come out unscathed - but if I can clean this rudder tube up both of my current eBay purchased "restoration projects" (Javelin and Rapier 2) will have a nice "time appropriate" brass rudder mounts.

[zooma]

The rudder post that suffered some distress as it was being extracted from the hull was straightened by rolling it on the table of my bandsaw and gently tapping the "high point" until it rolled more or less flat.

The axle shaft was straight and now turns inside the post more freely.

The rudder blade is detached from the shaft with plenty of lumpy solder blobs around it and the end of the shaft where they join together, so I will clean them up and see if I can soldering them together neatly and possibly drill and pin it.

I gently wound the worn brass nut up and down the shaft a few time with some thread cutting paste smeared on the threads and the nut runs up and down the shaft a little more freely - which is just as well as I cannot find out what thread is used on these old brass rudders?

It is a very fine thread and not an M6 as I had hoped.  I also have a box of 1/4" BSF nuts and this thread is also quite course when compared with the rudder shaft .

I will try to preserve the original brass nut as its the only one I have - but if anyone knows what the actual thread is I will try to find and buy a couple of spare nuts.  They do not have to be brass as the nut will be encapsulated with resin once it if fitted so give it a bit of extra support.

[tonyH]

Tutorial 1. Use of Hammer 1.

[madwelshman]

Making good progress there Bob. Rails look good too 


Interesting to read about the forward positioning of the shaft and rudder on Rapier #1 and that it works so well.
Just goes to show that conventional isn't always best.


Keep up the good work.


Will

[zooma]

The rudder shaft tube has been restored and the chewed end has been "dressed" so the rudder has a smooth surface to turn against.

I still have no idea what screw thread they used on these old brass rudders so I am going to chance using the "less than prefect" original brass nut.

If I can tighten it down reasonably well without stripping the remains of the thread, I will secure it with Araldite and then glass fibre it in later to give it some extra support.

The tube height will also be shortened by 1/2" to reduce the leverage on it when it is in use in the boat.

[zooma]

The brass rudder tube post was shortened by 1/2" and has been fitted back into the hull 4" forwards of the transom.

Sadly I could not fit my new brass water scoop - because the threaded part of the shaft is too short to pass through the keel!

When fully inserted the threaded section is not in sight and only a small stub of the tube to fit the cooling hose onto is visible - not enough to push the tube onto even if the scoop was only glued in without using a nut to secure it.

Another problem with the brass water pick-up is that the top part that has the silicone cooling tubing pushed over it is only a plain tube - it does not have any ribs to help prevent the tube from slipping off.  I know that silicone tube does have a good "bite" and is unlikely to slip off but it would not have been too much of a problem to add a rib to the programming to add a little security.

The upshot of this is that I have fitted a plastic water cooling pick-up as that has enough threaded section to pass completely through the keel and leave plenty of thread left to wind the retaining nut down to secure it (even with a thick brass washer fitted).

When the rudder and water cooling pick-up was fitted, I was able to make and fit a plywood plate to mount the steering servo onto. This was screwed onto a sturdy pair of mounts that have been Araldited into the hull.  When the glue has set I will unscrew the plate and glass fibre the mounts firmly into the hull.  The temporary plate fixing screws can be removed when the hole is cut out for the servo to fit into,  and the screw holes can be countersunk and a larger size of screw used for the permanent fix.

The brass scoop will not be wasted - I will fit it in a glass fibre hulled boat that does not have a keel - or I could mount it off-set to one side of the keel (like we used to do with the nitro and petrol powered boats to help counter the torque steering).

[Stuw]

The rudder shaft tube has been restored and the chewed end has been "dressed" so the rudder has a smooth surface to turn against.

I still have no idea what screw thread they used on these old brass rudders so I am going to chance using the "less than prefect" original brass nut.

If I can tighten it down reasonably well without stripping the remains of the thread, I will secure it with Araldite and then glass fibre it in later to give it some extra support.

The tube height will also be shortened by 1/2" to reduce the leverage on it when it is in use in the boat.

I’m re-using my old brass rudder post as well. Looks better than the plastic offerings today. It sounds like my thread  is in better shape than yours.


You are making great progress Bob. I found similar issues with that new brass water scoop but thought it could work if only the tip was poking out of the hull (as I saw on the Riva thread pictures I believe?). Whether it would be effective enough I don’t know. Haven’t tackled this yet. I might offset through the hull as an option. Or go plastic as you have done. I also noticed the lack of a ridge to help the silicone tube stay on!


Now I want to sand the underside of the boat and to get a better run at it, the strakes could do with coming off! It would also allow me to examine the hull underneath. I have purchased some obechie strip. I think I shall be bold and renew the strakes as they are rounded in places and would look better if done properly.


I’ve got all the sticky silver tape off but still to remove the glue. It was tricky getting right up the inside of the engine bay! All of the silicone sealant has been slowly scraped out of the transom area and upper bulkhead edges.


In the meantime my red anodized pushrod balljoints have arrived. They are M3 to the beefed up servo horn, and M2 threads for the pushrods. I’ve then got M2 to M2 plastic mini balljoints into the rudder tiller arm that was purchased to go atop my old brass rudder. The tiller is a black Glassfibre mount with a brass insert and a grub screw. I went for M2 pushrod as the tiller didn’t look wide enough to take M3 in my opinion.

[zooma]

Hi Stuw,

Scraping away glue residue etc inside an old hull does take time - but it will be well worth it when it is done and it sounds like you are making good progress.

It's a shame to take the old strakes off of your hull, and depending how you fixed them on they may or may not be a little tricky to take off. If they are still really well attached and you are sure you want to remove them I think I would probably sand them away rather than risk pulling them off.

If the strakes are loose or not stuck too well and you can get a good grip with a pair of pincers, the rolling action may cause less potential damage than pulling them or levering them off but you would still need to be careful not to damage the bottom skins.

I have no mechanical fixes(brass nails etc) on the strakes that I have just fitted to the Rapier1 and the Javelin - I used thin fast setting super-glue and I am hoping that the long term bond will stay permanently secure.  I used PVA with lots of nails to hold the strakes in place when I fitted the strakes on the Swordsman and pulled the nails out when the glue had dried.  The super-glue method was much faster and if the bond stays firm I would not use PVA for this job again.

Having checked the cockpit floor height etc I am planning to fit the ESC mounting shelf in the same place as Rapier1 (but under the cockpit floor).  If this works out it will save having to extend any LiPo or ESC wires so I can keep them all as short as possible.  If I get this done today and it works I will let you know.

Stay safe,

Bob.

[tonyH]

Water scoop shortfall!

[Stuw]

Ah. Yep I hadn’t thought about the fact that the strakes could rip away some of the hull. Will pause on that. Nice and sturdy looking servo mount.


I’ve never used glassfibre. Are you able at some point to briefly explain how you would do this to strengthen the hull etc. or point me in the right direction. Do you use glass cloth and if so what type/thickness would you recommend please?


It looks like there is either epoxy or resin around the rudder post and along the keel inside. Is that glassfibre?

[zooma]

Ah. Yep I hadn’t thought about the fact that the strakes could rip away some of the hull. Will pause on that. Nice and sturdy looking servo mount.


I’ve never used glassfibre. Are you able at some point to briefly explain how you would do this to strengthen the hull etc. or point me in the right direction. Do you use glass cloth and if so what type/thickness would you recommend please?


It looks like there is either epoxy or resin around the rudder post and along the keel inside. Is that glassfibre?

Yes - the previous owner poured some glass fibre resin into the hull around the keel and it has done a good job preserving and protecting it from the fuel of the nitro engine that it had in it.

Working with glass fibre resin is really simple and easy.

Bondaglass comes with a harder (like P38) - and you can start with a small kit that has the resin, harder and the chopped matting etc in the box.

Cut some chopped matting roughly but oversized shape to fit where you want it to reinforce before you start.

Pour some of the resin into an old spray can cap (or whatever you have spare) give it a squirt of harder and stir it together.

Brush the resin onto the wood and lay some (pre cut) matting onto it and then stipple it into the resin.  The resin soaks easily into the matting and is easy to manipulate.

You can add more matting or resin as you stipple to kept it wet enough and it will dry in a few minutes.  It does not seem to be as temperature sensitive as epoxy and I find it easier to work with.

Buy some cheap disposable brushes  - they will dry as hard as a rock!  Cheap disposable gloves are also a good idea!

Other makes of resin are available and you can use cloth instead of chopped matting if you like, but the matting conforms easily to shape and is handy when reinforcing corners and around mounts etc.

[ChrisF]

It's a pity that Raboesch don't make two different lengths of water scoops as they are very nicely made - one for when just passing through the hull and one for passing through the keel.

Stu - where did you get your anodised ball joints from and the servo arms?

Chris

[Stuw]

Yes - the previous owner poured some glass fibre resin into the hull around the keel and it has done a good job preserving and protecting it from the fuel of the nitro engine that it had in it.

Working with glass fibre resin is really simple and easy.

Bondaglass comes with a harder (like P38) - and you can start with a small kit that has the resin, harder and the chopped matting etc in the box.

Cut some chopped matting roughly but oversized shape to fit where you want it to reinforce before you start.

Pour some of the resin into an old spray can cap (or whatever you have spare) give it a squirt of harder and stir it together.

Brush the resin onto the wood and lay some (pre cut) matting onto it and then stipple it into the resin.  The resin soaks easily into the matting and is easy to manipulate.

You can add more matting or resin as you stipple to kept it wet enough and it will dry in a few minutes.  It does not seem to be as temperature sensitive as epoxy and I find it easier to work with.

Buy some cheap disposable brushes  - they will dry as hard as a rock!  Cheap disposable gloves are also a good idea!

Other makes of resin are available and you can use cloth instead of chopped matting if you like, but the matting conforms easily to shape and is handy when reinforcing corners and around mounts etc.

Brilliant, thanks Bob.

[Stuw]

It's a pity that Raboesch don't make two different lengths of water scoops as they are very nicely made - one for when just passing through the hull and one for passing through the keel.

Stu - where did you get your anodised ball joints from and the servo arms?

Chris

I’ve just found this thread on water scoops with a handy tip on securing the silicone tube with a further short section of tube over the top! [size=78%]https://www.modelboatmayhem.co.uk/forum/index.php/topic,28691.25.html[/size]


Pushrod connectors - [size=78%]https://www.noahsrcark.co.uk/products/d4fcc5ab95/131444000000096853[/size]


Servo arm - fastrax  ( as well as securing screw into servo, they have two bolts under the head that tighten the collar around the servo marked in red on my photo) - [size=78%]https://www.modelsport.co.uk/index.php?product_id=363137&gclid=EAIaIQobChMIo8qeyMaR7wIV0NPtCh3EwARREAQYAiABEgJVxfD_BwE[/size]


Only found out servo arm holes were M3 threaded once they arrived!

[zooma]

I bought my red anodised rod-ends from eBay - very good quality and inexpensive.

[ChrisF]

Thanks Stu, they look nice quality.

Bob, I did have a look on Ebay but didn't know which ones you'd got! Did you buy the 3mm rod separately as the supplied lengths don't look that long?

Chris

[zooma]

Thanks Stu, they look nice quality.

Bob, I did have a look on Ebay but didn't know which ones you'd got! Did you buy the 3mm rod separately as the supplied lengths don't look that long?

Chris

https://www.ebay.co.uk/itm/8pcs-M3-Metal-Ball-Head-Holder-Link-Rod-End-Ball-Joint-for-1-10-Car-Tru-D-/174281843956?hash=item289401e4f4


These are the ones that I have used and at £5.90 for 8 they are a very good price....and excellent quality too!

[Stuw]

Thanks Stu, they look nice quality.

Bob, I did have a look on Ebay but didn't know which ones you'd got! Did you buy the 3mm rod separately as the supplied lengths don't look that long?

Chris

Just to confirm, the ones that I linked to are M3 to the servo arm but only M2 sized for pushrod. Couldn’t find any others of this sizing combination online. Bobs are better value. If I hadn’t gone for M2 rod I would have gone for them. My tiller also dictated M2 for me. It was a bit of trial and error as sometimes you only find out the detailed sizing when they arrive!

[ChrisF]

Thanks chaps

I have uses for both sizes, nice bit of bling!

Chris

[zooma]

Only black or blue in stock at the moment:-


https://www.ebay.co.uk/itm/8pcs-M3-Metal-Ball-Head-Holder-Link-Rod-End-Ball-Joint-for-1-10-RC-Car-Truck-/174348245515?var=&hash=item2897f71a0b


Same supplier.

Black are £5.90 for 8.

Silver and red are out of stock and the blue ones are slightly more expensive at £6.34 for 8.

Blue has got to be a good colour for your Fairey fleet ?

[mrzippy]

Guys water scoops are a doddle to make !
in the good old i.c. powered days a simple short length of straight pipe would be positioned behind the prop at a very shallow angle,
slash cut vertically and glassed into the hull, job done !!

IMHO. modern day fast electric powered boats benefit from seperate cold water systems -
I cool the motor, the esc. and in some instances (Swordsman) a sound generator with three seperate systems,
all supplied by a single water scoop.

I make my own twin/triple scoops from brass or copper tube with a simple el-cheapo modeling pipe bender -
(a mini version of the traditional plumbers tool) used to bend a curve in the pipe, which is slash cut vertically.
Two or three are soldered back to back and filed into a single streamlined shape (similar to old Aerokits threaded brass inlets),
the internal ends are bent in different directions to allow easy silicone pipe fitting.

Leave just enough scoop projecting below the hull to catch prop wash, without causing too much drag -
modern high speed fast electric racers have the tiniest streamlined scoops sticking out of the hull in all manner of positions,
not necessarily behind the prop.

[zooma]

Are your three pick-up pipes stacked (under-water) one on top of the other?

Having three separate water-cooled systems running from a single multi-stacked pick-up is interesting - do you have any pictures?

I don't have a use for three separate cooling systems, but I could have a use for two (to cool the ESC and the motor).  I have already been trying to find-out where to buy one of the alloy "Y" shaped joints so that I could split the input from my single scoop into two systems.

These "Y junctions are sometimes used to join air pipes on aquariums .  The posh looking anodised alloy one that I have seen pictured here on the Mayhem some time back is the type that I would like to find.......it won't work any better than any of the others others that I have seen - but I do like the "bling" factor, and I remember them being available in a choice of colours some time ago too!.

Two separate pick-ups sounds interesting.

The flush fitting pick-ups that can be placed almost anywhere on the bottom of the hull also look interesting and they would give no resistance at all, but I do worry about their structural integrity - if one became detached it would cause a flood.  I am guessing that covering them with an epoxy or glass fibre coating inside the hull would be the best way to ensure they don't break away from the inside of the hull skin?

[mrzippy]

Hi Zooma,
Yes pre bent pipes are stacked one on top of the other before soldering, see photos attached below -
it's also handy to be able to bend the internal ends in what direction suits the models installation,
or continue the metal pipe along the inside of the hull towards the motor etc.

I've seen fast electric racing mono hulls, where weight is absolutely critical,
going to the extreme of having the motor cooling scoop coming into the hull at the bow at the side of the motor,
purely to save the weight of a length of silicone tube !!