Hope you didn't stick the boat to your fingers 😲
We're getting there 👍

Hi Dave - like the talc idea which will be next weekend as my old man is down for the weekend and we are out and about all over the place. May even get a chance on an evening if Mrs Mac allows operations in the house lol. Which will allow me to move on next weekend.

Hi Doug - nothing lost in translation always intended to finish off with filler for cosmetics probably just my application and communication on here lol. I must admit that 5min stuff is bloody quick setting it is definitely PANIC it's going off NOW 😂😂😂

Hi Dave, agree with the talc idea, sometimes I file a piece of busted terracotta flower pot to powder and mix that with the resin. But usually to repair Gisela's busted garden ornaments not for boat models, but no reason why not😉 But then that's why I suggested the thicker two part glue not the liquid resin for this 'fix'.
Re hardeners: as far as I know all are peroxide based but the concentration is different for the various 'speed' glues.
Frankly I would have thought that the faster mix on the inside would have accelerated the outer mix, at least at the interface between the two!
BTW: it was never suggested to use the epoxy as filler! The resin was just to soak and harden the balsa wedges and hold everything in place.
I'm sure I wrote to the effect; when fully cured THEN use filler on the outside of the hull for the cosmetics. Something lost in interpretation??
Anyway step by step Neil is reaching his goal! 👍

@ Neil; you'll need to get a shift on with the 5 min mix! 5 mins is the hard setting time, working time before it goes too stiff to move is only about 2mins!!!🤔
Cheers Doug 😎

Hi neil
If the resin was runny I suspect you omitted or did not mix the hardener sufficiently or the two mixes interacted with the quicker inside mix setting quicker and stopping the longer mix from setting. if you make a correct mix and cover the soft resin as suggested it should all set nicely. You could add some talc to the runny resin to thicken it up before adding the new mix.
Just a thought but possibly there are different hardeners for the slow and fast cure resins. I do know different brands don't always work together.
You are nearly there and will be soon ready to move onto the next stage.
Dave

Hi Doug - you're spot on as always it was two different batches. The inside was a 5 minute working and the outside a 30 minute working type epoxy. Thinking was longer on the outside to make sure all holes were filled which has worked sort of.

HI Dave - the day did it was lovely and warm so thought I'd be on a winner. I've tried a hair dryer on medium heat but the epoxy goes runny 😣😣. I think I'm going for the removal option a bit of 5 min type epoxy and then finish off with filler. There was still some space filler on the first attempt at epoxy but there'll be more this time.

Thanks for advice again I will get this right 🤣🤣

Hi neil
Mixture and temp are all important. You could try gentle heat from a hairdryer to harden the resin.

Adding extra hardener to the mix is not advisable as it can lead to unpredictable results.

Epoxy is not ideal as a filler but you can make it more suitable by adding microballoons to the mix. This will result in a very hard finish which you can sand to shape.

Personally I use car body filler when fixing in prop shafts / rudder tubes etc as this can be easily faired into the hull contour and will easily take paint. I have successfully used this over epoxy joints.

Whatever you use you need to make sure the work environment is not too cold. The temperatures have dropped considerably over the last few weeks so you may need to provide a warm environment to assist the curing process.
Dave

Curious that inside worked and outside didn't! is it contaminated with something or was it a different batch?
Whatever, if some is removable with a knife and / or chisel do that.
Then work in the stiffer epoxy glue and try to work it in to the first epoxy which is still soft. You might be better of with the slow version with an extra dollop of hardener, this version (the green one in the pic) will give you more time to work the stuff in.
Good luck, don't get stuck up 😉

Cheers Doug the inside of the hull has set rock solid just the outside boo hoo. Can I use the new epoxy over the top of the not set epoxy or do I have to remove it with a knife?

Hi Neil, not enough hardener?
Try this: use a thick two part epoxy glue, such as UHU Fast - the 5 minute version so get a shift on! instead of mixing 1 to 1 mix 1 part glue to 1.5 parts hardener (length of the 'worms'!)
Work it well into the holes to mix it with the original epoxy as much as possible. if you're not happy with 5 mins working time use the slow version which gives you about 90 mins fiddlin' time. NOTE: With extra hardener the working times will be shortened so try and get done in about 60 mins. You'll soon notice when you can't fiddle any more - the spatula will start to stick to the workpiece😲 Good luck, Doug 👍

Well it looks like I mixed the epoxy wrong as its still tacky and pliable after a week indoors - back to the drawing board on this one I think. Any ideas 😭😭😭

Hi Neil, your Dad's dead right!
I've come to wonder how the heck I ever found time to go to work😉 important is to know just what you want to do with your time long before you retire - and then DO IT! Like wot i am now 😁

Yep, the cosmetics are to tidy up around all the hull and bulkhead breakthroughs and blend them in to the underlying structure. With special attention to ensuring that all hull breakthroughs (prop shaft / rudder shaft etc) are thoroughly waterproofed!!
Good sealing on bulkhead breakthroughs is just(!) for 'Damage Control' to limit the spread of ingressive water in case summat nasty happens🤔 Cheers Doug 😎

Retirement is the way ahead and I bet you're busier now than when at work. My old man is always complaining there is not enough time in the day 😁😁😁😁

I think I need to fill a little more on the right hand side as it's sunk back a little but like you say just leave to dry for a good while. I presume the cosmetics you talk about is for streamlining over the top of the epoxy and trying to sand the epoxy back?

Now we're getting somewhere 👍
To fix your rudder 'guide' (stock shaft) use the same technique as for the prop shaft tube. cosmetics with 2 part filler paste.
He he! it's only League Bowling (first match of new season today, I averaged 187 was happy with that😊) and GF's travel wishes that get in the way for me now 😊 Lot to be said for retirement😉
Plug on Neil, cheers Doug 😎

Sometimes I hate work it gets in the way but I've managed to get the first fix for the prop tube at last now to leave for a while as work and courses in the way again.

I have also managed to open the hole for rudder guide and presume this needs a bit of expoxy resin to secure it in place?

The oiler is also fitted and a bit of cleaning of the inner hull to remove some of the old paint ready for sanding sealer coat after I've mounted and aligned the motor - not looking forward to that at all if past experience is anything to go by. But now the old mount is out there is more space and the prop and shaft is at a much better angle thanks to Dave and Doug😁😁

To neilmc, tried to reply to your PM but got it bounced back.

Wow check me out I've been promoted to Commander as well thanks guys for all your help. Does my naval pension go up as well 😊

Dave I won't take any photos yet as it's literally just the hull. You may remeber last year you provide loads of help on my plywood delamination issue and the build blog is still there which shows me reducing her to nothing and making new superstructure side from scratch. The rest of her is in boxes 😂😂😂😂

Well that's her soaking in epoxy 😁😁. I've applied a thin coat to the newly exposed wood and now plugged the water pick up hole. Resized the the rudder hole to take the new rudder tube but decided not to fix just yet. Today has been hectic and not spent as much time on her as I would have liked but no point in rushing it as it's been 6 years to get to this stage 😁😁😁😁

Wingcoax sent you a Private Message 😁

To neilmc, it's a long time since i saw the old Alliance. I was involved in the restoration of the main electrical switchboard when she was still in the water.

Hi Dave, I was answering the query about the new shaft holes in the keel and bulkheads to finally fix the shaft. NOT 'soaking' the whole hull!!
Doug

Hi neil
Good to see your are progressing.
It's good to see that Paul has joined in the discussion and offered help.👍 He has a superb model at the larger scale and has been an avid supporter of Fireboats and the site since its inception.
With this small model it is important to keep the weight to a minimum and whilst sealing holes with glue and filler is OK, I would go easy with soaking the wood in epoxy, it's heavy. Far better to cover with a sheet of tissue/glass cloth and apply a thin coat spread with a plastic (credit Card size) spatula to work well into the covering.
It would be good to see a few pics of your whole model. Say two side views, a top view and a stern view. if you can weigh that would also be useful.
Might help when you need further advice on the build
Cheers
Dave

Hi Neil, forgot to mention, Re the 'new exposed wood': when you are sure the shaft is correctly lined up on the keel soak the hull and bulkhead breakthroughs, wedges etc with 2 part epoxy and leave in a quiet place (!) to cure. This will also seal any exposed wood. Then tidy up, fill and fettle inside and out. ---> Good to go! (As our colonial brothers 😉 say!)
Doug 😎

PS: regarding testing for 'true' on glass-
3mm float glass does bend quite significantly 🤔
That's why mirrors are best, they are usually at least 6mm (for a good'n) and maybe hardened as well. 9mm hardened is better. Ask the local glazier for an off cut! Doug (yawnnn) 😎

Thanks for everything tonight learning more each time I'm on here and at the moment its keeping me out of trouble😁😁😁

Paul - I was looking through my bits of paperwork today and found a letter from Peter when I joined this site 6 years ago - yes that's how I've been going on this project. The letter was to do with the actual fireboat and what colour grey was used so at one point I was quite far on. Then it all went wrong with delamination of the plywood and major misalignment issues. Peter was a great a guy and really helpful

Paul - luckily I have a new shaft as purchased one the other as Dave said about about making sure it true before fitting due to vibration issues later on if it wasn't true.

Doug - I'm going to go for your's and Dave suggestion of fitting a fillet as to be honest it sounds easier and like Paul says its underwater so wont be seen and if it ever gets in the water wouldn't want to lose it on first trip out😁😁😁

Maybe black pack-ice 😡😉 Any penguins about at the time 😁
Anyway glad you got her back more or less in one DRY piece!

Re 'as original, I'm not an aficionado of these boats but weren't they all twin screw? Cos Neil's boat with only one is not 'true' anyway so the fillet may actually make it look better than a superfluous bracket would.

Good bit of brainstorming tonight 👍 hope it helped Neil and other newbies.
Bedtime here now as well, we're an hour ahead of you lot😉
Sooo 'up the wooden stairs to Bedfordshire', nite all, yaaaawn 😎
PS like the pinning idea, will use it on my destroyer 👍

Hi Doug (time for bed now!)

dont know to this day what it was, water was high, it was winter, its a big lake, no sign of something floating, but it was a right loud whack! it was in my home town of Liverpool, so maybe was a stolen car or shopping trolley dropped in the lake!😁

I was convinced it was a right off, luckily it survived!

(you had a much better description of the skeg!)

Neil,

the suggestions about prop support are all valid, just different takes on things. I would (if you intend to repaint the hull) sand off to key, or prime the old paint prior to installing the shaft, as it will be easier to repaint and prep. Question, sorry if I missed this, is that a new shaft with new bearings? if not get new from shg marine (they are at the Blackpool, show, and the midlands engineering show if you can get to either, I'm not sure where you are?) they are dirt cheap, called aceteal or something similar, they water lubricate, and cost about £2 each. Roll the inner shaft on a piece of glass or a mirror, this will tell you if its bent, any sign of this, get a new one, or you might have alignment and vibration issues. (glass is totally flat! there's a free tip to test you prop shafts ha ha !!👍)
same can be bought from shg, and get stainless.

Back to the support, the thing Dave mentions is a piece of wood that fits between the hull, and the shaft. The shaft is then epoxied to this, giving support, but it wont be true to original. You have the original support, so remodel this to fit your new angle. if you use any bolts etc to secure, use stainless so they don't rust. Once painted, it will be hidden, and its underneath anyway so cant be seen. it will need to be tight to the outershaft, once positioned, you could solder, as they are both brass, and either feed into the hull bend over and epoxy, or screw as per original. Here is my big fireboat, its twin, but the concept is the same, the support came into the hull, and on this example, I put a brass pin through, and epoxied it all

Hi Neil, the pics look good 👍 You have 11/16" from keel to shaft centre so your max prop diameter is 32mm. You might squeeze a 35 in if you flat off the keel to hull behind the shaft.
The fillet is a triangular piece of ply (or hardwood if you have some scraps) fitted between the top of the tube and the hull bottom (keel plate in your case) and reaching from the end of the tube just in front of the prop to the hull exit point and completely filling (hence the name 😉) the whole gap. Min 6mm thickness would be good.
Cheers Doug 😎

Hi Paul, Get where you're at. But Dave's fillet would have protected the hull hull even better by spreading the load instead of just directing all the force straight up that narrow bracket which concentrates it all in one place.
If your pond is that dangerous fit a full skeg!! 😉
In Neil's case I would fit the fillet above the tube and use part of his old bracket to wrap around the tube just before the prop to prevent any possible side whip. Unlikely but who knows what monster motors he may fit in the future? Like you say - a chaque un a son goût!
Cheers Doug 😎

Doug no nut and bolt honest 😜😜

What is this fillet you and Dave talk about and how is it achieved as I presume its easier than fitting the support and drilling more holes in the keel?

Also now I've extended the hole I obviously exposed new wood do I need to apply sanding sealer before applying glue or just slap it one.

Do the photos look OK to start gluing??

ha, got you! check this out Doug!

Huntsman, single screw, with prop support, A simple brass strip, epoxied into the hull. Sailing around, Wham! something just under the water, fuzzy picture but the shaft bent (and its a 5mm stainless one) rudder as you see, without internal and external support, that hull would have cracked, boat could have sunk. I get what you say, but its at the build stage that you (builder) can decide what to do prior to painting etc. The twin screw pic was just for reference, I didn't have a pic of the same thing for single screw, but its each to their own, and we all have a different view on things, which is great👍

I like the layout of yours pmdevlin as its shows me that the bulkhead behind the motor isn't actually structural and I did struggle with it today ended up cutting a section out of it to ease the motor in.

Nut and bolt ?? Ugh😡
You don't need a torch. A standard 25W mains soldering iron and 1mm cored solder (with flux in the cores!) is quite sufficient. 50W is of course quicker, but the 25 is more useful for other smaller jobs as well, like railings, masts, ladders ...
Just make sure the inside surfaces you want to join together are perfectly clean and grease free. That includes finger prints!😉
Cheers Doug 😎

I must admit I like the idea of a prop support as it looks closer to the original. Doug suggested using the old one I have and now the angle is less I can see how this would work. All I need is some solder and torch or just simply a BA nut and bolt😁😁

Yes Paul, with the boat in your picture you are right. BUT it has two props so the tubes and shafts go through the thin hull and have no other protection or support. Like in my twin and multi screw destroyer and cruiser. Also they are supporting bearings for the shaft cos the tubes stop at the hull exits.
Here, as Dave rightly pointed out, and I also showed in the pics of my Sea Scout; if the shaft tube is properly fitted in the keel it has all the support it needs and I've never seen internal damage from a 'knock' to a prop shaft!?
The fillet from tube to keel does the rest and absorbs any 'knocks'. if you want belt and braces wrap a thin brass strip around the tube just before the prop and epoxy it to the sides of the fillet plate. Which by the way is above and not below the tube!
and Neil; keep Paul well away from your models!! 😉
Cheers Doug 😎

that angle is way better, give yourself a bit of room for a bigger prop, say your 40mm, just incase.
For reference, here is my original set up with a brushed 700 motor, direct drive, it ran hot! then I used a gearbox, it ran cooller, but the boat was getting very heavy by now. Currently its a brushless direct drive, its been ignored for a few years now, I must get it out and use it again. its an original Aerokits, built in 1963 by my Uncle as a straight runner ic, the ended up in my parents attic for 30 years

what a rip off that is, its just a simple strip of brass, make it yourself Neil, it will also give more satisfaction when you do it yourself, and save £9!!

Not to compromise other opinions, but I think you need some sort of prop support, even single screw. if you are ham fisted like me, it can get knocked, dropped, or could hit something in the water. With no support, the "knock" can cause structural damage inside the hull, I'm always knocking my models with clumsy hands, so always "over engineer" things so they don't fall off! . Dave suggested a fillet under the prop, that would work, it doesn't have to be anything more complicated, however the real boat was this (pic) its got a support like the one you bought👍 so it depends how accurate you want to be

Standard Saturday Mrs Mac decided I had other things to do before being allowed out to play but I think I've got there, just need to check it's right before gluing up. OK so I lied that I wouldn't be asking more questions on this topic😁😁

The hole has been opened out enough to achieve 3/4" but the photo doesn't really show it. it took some time to achieve it as well more time than I thought, even used my dremel at one point😁. But pmdevlin's tip on using a disc was a great help.

The position of the outer tube on the hull needs a slight adjustment but nothing major and still achievable as no glue.

I did have a check fit of the motor and came across another issue as there was no way I could achieve alignment of the shaft and motor which was made easier by Doug's universal coupling idea😁. I went for removing the last remaining piece of the old motor mount (should have listened to Dave a year ago) which took about an hour as it was glued in good and proper.😤😤😤😤😤

There is some clearance on the hull from the prop so think I'll be going for a 30mm prop as suggested by Dave as to my surprise mine is 40mm diameter. Hopefully the arrangement is all good and I can use Dave's and Doug's tips on getting it secured. I still need to blank off the water pick up and fit the new rudder tube. Also I think the motor alignment will still be interesting as after removing the last bit of the old mount the motor was interfering with the bulkhead behind it so removed so it. Also will possibly need to take some out of the hull centre piece to achieve a perfect alignment.

Hopefully tomorrow will go well as will also fitting the oiler as seen on Robbob's Build Blog.

Hi Neil,my respect for your 'silent service' 👍
I've been on a few subs, mostly old Type 206 or 209s, some very old 30+ years in Ecuador 🤔 Kept bangin' me nut 😭 6' 2" ain't built for submarining 😡
Wow 9.75 is expensive for something you can snip out of a bean can in five minutes!! Anyway get your bread back 👍
Like I said, we've bin there and dun that, so also learned much the hard way and others helped US sort out the mess😉
Pleased to see that it helps and you are progressing 😊
Cheers Doug 😎

Well Dave M was right I wont be using this and Doug was right I bought the wrong one so it'll be going back which is bonus at £9.75😁

HI Doug
Oh yes I was a 'Pig Boater' for 30 years and loved every moment been there and got the t shirt lol😁😁😁😁

HMS Alliance! Aha! So you were in the 'Silent Service', a 'pig boater'!! 😁
Don't forget to add a few mm clearance to the disc!!!
SITREP with EYEBALL ASAP please 😉
Cheers Doug 😎
PS Fully understand the 'shiny' things, that's why my 'stash' is getting out of hand 😲

Hi To you all thank you for the continued advice it is making life so much easier and I do like it when the thinking is done by experts.
Paul
The disc idea is an absolute bonus and will be using it for sure as it takes away the need for continued measurements.
Dave
The water scoop is going as like you and Doug say I don't need it no working monitors for me, just a working boat would be good. I'll be using measurements given to achieve shaft positioning as at the moment I have a 2 blade prop which I think is 30mm diameter so disc to suit will be used.
Doug
I like KISS it's worked for me loads of times in the past but I can't help buying shining things 😁😁😁
The shim idea on the prop tube is a good one but may still go for a support even though not needed it shines 🤣🤣🤣🤣. But it may still go back to the filler piece as all depends on how difficult it is to fit the A frame support. I purchased one at 8mm for the tube and not 4mm for the shaft.
I'm looking forward to the weekend to get started and even set an alarm for an early start which is unusual for me. Im off to HMS Alliance as I do volunteer guiding there otherwise id be starting now.

Will keep you all posted hopefully with good news and no more questions - well on this bit anyway 🤣🤣

Yep! KISS; Keep it Stupid & Simple!! 😎
Most of my ships have twin or more screws so I need the brackets. But not on my single screw Sea Scout or fish cutter. 😉
Only ever had a water scoop to supply a pump for a fire monitor experiment.
Mostly used to keep little boys fingers at a distance 😁
Up to now have never needed water cooling, at most a fan (ex PC processor fan) for the ESC.
Cheers Doug 😎

Neil
Your model is the 34" Crash tender with one prop.
Twin prop versions as per the real craft do need the support.
On a single screw you can add a fillet of wood to fill the space and provide the support.

Paul may well have used a 50mm prop on his model but my measurements were fo a 30mm 3 blade brass prop and that works perfectly. Using a disc cut to the size of the prop is a useful tip when fitting the prop tube

For very fast models you will need a water scoop but for a novice this is an additional complication and I doubt if you will need one.

Hope you are progressing with fitting the shaft

Cheers
Dave

Exactly 👍👍

Ill chip in!

Pictures tell a story. Ok, a twin shaft, but the principle is the same. Imagine the angle of shaft you have, then propeller is pushing up, get it a shallow angle, and its now pushing forward. On the 34" fireboat, largest prop you will end up with is 50mm, so cut a dics 50mm, attach to your shaft, with a flat on it so it sits on the hull, viola, here is your prop angle👍

Prop support, use a strip of brass, heat it, and bend around same diameter rod (as your outer shaft, not on the shaft as the heat could damage the bearings), clamp together and either solder or use a small nut and bolt, fit through a slot in the hull, and then bend the side over, like wings, inside the hull, and epoxy.

Paul

Fit a water pick up, its easier at the build time, than regretting it later, you don't have to use it if its not necessary

I thought it was a good idea looks like I'll be sending it back 😁😁😁😁😁
Cheers Dave and Doug didn't do bad there wrong one and not even needed I thought I'd read something 🤣🤣🤣