Hi neil
Not what you require. This is a bearing and frame for a shaft that extends beyond the end of the propshaft.

The original design for an IC motor had the shaft much further from the hull, hence this support was required.

As I advised on your other post you do not need this support. Just fill the gap between the prop tube and the hull with a triangular sliver of wood to provide support. The shaft should be no more than 3/4" below the hull at the prop end.
Dave

'A' frame !!?? You only need a 'P' 😉
Could have recycled the old bracket.
What ever you do don't screw it to the hull, make a slot.
Cheers Doug 😎

I did wonder last night as couldn't find one with the right dimensions. But did go shopping on modelboatbits- an oiler an universal coupling and an A frame hopefully they'll be here for weekend not that I'll need them all as lots to do as you know 😁😁😁😁

I was wondering that as well 🤔

Hi Neil
That link for the seal is for a flexishaft drive. Totally different to a propshaft and proptube. Used by the fast racing fraternity.
I am not sure it would work in your setup.
Anyone used one with a solid propshaft?
Dave

Thanks for the link Neil, 👍 I see it include the oiler connection.
Cheers Doug 😎

OK, 'the spoils of war' !
Or how about a Sherman with the canvas float bag or the mine clearing flail? 😁
Now THAT would look unusual 😉 specially if you made 'em work 😁

Yes I know it should be a Sherman or Matilda, tbh they look lame in comparison to the Tiger, so it's my LCM3 & it's getting a Tiger🖕😂
Hehe Mark👏
Cheers
Wayne

Hi Doug
This is the shaft seal I mentioned
Look at this on eBay http://www.ebay.co.uk/itm/391200714649

Wayne ,still cant guess what it a is,oops sorry that was another topic 😁😁😁

Hi Wayne, ta for the file 👍👍 Oilers look good.
You're dead right about 'loads of the same thing' that is my main interest and what prompted me to buy the beast. if I go oily then I will need 15 for my current fleet! 4 for Belfast alone. I take it I can scale it for smaller shafts on ships in the pipeline??
Tank looks great but isn't that a Tiger? Don't you need a Sherman or Matilda etc for an LCM?
You queried 'Tank steering' a little while ago - looks like you're about to learn all about it 😉
Cheers Doug 😎

Hi Neil, re oiler etc -
KISS! Keep it Stupid & Simple 👍😉
Plenty of time later for embellishments - WHEN the basics work!

BTW; you mentioned you had found some shaft seals - can you post the link to them please - ta in advance 😊
Cheers Doug 😎

Ahh sod it, here's a pic of a proof of concept print I've done, printed at roughly 1/56 scale, looks good to me so I'm on with printing one at 1/16 to fit my LCM3 landing craft.
Cheers
Wayne

Hi Doug, STL file emailed to you.

Marky, hehe I'm no master, I just load the files I find & press print lol😂

Neil, pics attached, the oiler is really simple, only takes a few mins to print.
3d printing makes it really easy to make loads of the same thing that look identical, I'm on with a side project at the moment that needs over 200 of the same part printing out, I'll save pics of that until it's nearing completion 👍
Cheers
Wayne

Wayne would be really interested to see what these 3d prints look like a few guys at work are constantly talking about it. Ones in the process of 3d printing his house extension for planning purposes 😮😮

Cheers Doug just jotted down what I need to do good idea as will save some head scratching come the weekend 😁😁
Dave understood on skeg and oiler in think my problem is I see something and decide it's a good idea which like you hinted adds more problems which will then put me off again and another year later I'm back with more questions lol.😃😃😃

Wayne as you are the grand master of 3d printing I don't think there's much you cant print

Hi Neil
Sorry was in a rush this morning so misnamed the water scoop hole as the skeg.
As regards the skeg you don't need it. Just fit the propshaft and then fill below with a fillet of wood as used in the original Aerokit models and mine.
An oiler is useful but your shaft doesn't have one and for a novice they can be difficult to fit. Like Doug I solder mine.
I see my friend Steve at Model Boat Bits stocks easy fit oilers and they would be fine if they are the right size for your propshaft. if you do get one make sure you remove the propshaft before drilling the tube and get all the swarf out afterwards.
Dave

Hi Wayne, good to hear👍 'Well done that man! Give the man a Scooby doll!" 😁
OR; can you send me the stl file? Would make a great (and useful😊) first project for my 3d printer 😉
If affirmative I'll PM my mail address.
Muchas gracias Doug 😎

I can 3D print shaft oilers if anyone is interested 👍
I'll post some pics when I get home from work
Cheers
Wayne

Re oiler. Yes always worth it. There's a good selection on the ModelBoatBits site and an excellent illustration of how to fit it!
Get one to fit the tube you have 😉
Fit it BEFORE you fit the tube in the hull! it's sooo much easier.
Also to clean out any residual swarf from the tube - very important!!!
I'm currently measuring up all my ships to order a batch of oilers, although I've also considered soldering tubes on myself😉
Cheers Doug 😎
BTW; don't leave the plan in your head! Jot down the steps you want to do in sequence as a reminder😉

Thanks Neil Pleased to hear that 👍😊 That's what we're here for 'The bin there - dun that brigade'! I've also received excellent tips here; especially re conversions to brushless and various modern materials and sources!
Don't wish your life away though! it's short enough - but can fully understand😉 Cheers Doug 😎

Hi Doug just been on modernist and saw an oiler system is it worth getting one for the shaft I have or should invite the bullet and just go for a Raboesch shaft? Presume if shaft was changed it would still be 8mm outer tube with a 4mm shaft?

Doug and Dave this is excellent information and things are becoming so much clearer and I have a plan in my head of what I need to do. This is a first for a long time 😂😂😂
I shall be shopping tonight with the hope it turns up by the weekend. I now don't want to be at work as the enthusiasm you have given is wishing the weekend closer.😉😉

Hi Neil, while you're on that site get one of these shaft alignment couplings
http://www.modelboatbits.com/UNIVERSAL-ALIGNMENT-TOOL
Check the diameters of your prop shaft and motor shaft before you order.
They are a great tool for lining up the motor with the shaft.
(I make my own on the lathe😉)
Cheers

"Make what you can - buy what you can't" 😉

Hi Neilmc.
You can buy ready made 'A' & 'P' frames from ModelBoatBits, great quality and not at all expensive.

A 'P' frame epoxied into the keel would do the trick.

http://www.modelboatbits.com/MAXIDRIVE-P-FRAME-4MM-1

Hope that's helpful.
Robbob

Agree 👍 The longer shaft is an advantage cos it provides more flexibility and 'wiggle room' inside the hull for the motor mounting.

One thing puzzles me! "Skeg hole"? Do you mean the water scoop hole?
I always understood that the skeg is the extension of the keel intended to protect the screw and rudder, and in many cases is a metal extension of the keel to support the bottom end of the rudder shaft!
See attached examples of rudder skegs; Billing Fish Cutter (an inherited restoration project!), Southampton tug, U25.

Neil; what you referred to as 'the skeg' is generally known as an 'A bracket' or 'Bearing bracket'. it's purpose is to support the final shaft bearing just before the prop. On full size ships the shaft tube does not extend all the way back to the prop. it stops at the hull exit and the 'A' bracket supports the final bearing at the end of the actual drive shaft.
See final pic showing the stbd. outer shaft of my HMS Belfast cruiser.
(About to be fitted with new brass Raboesch props!)
If I were you I would not even try to bend the bracket again, and would not screw it onto the hull as it was. This is a double violation of the hull integrity and will eventually cause water to creep into the wood and start it rotting!
I would cut off the right angles and solder the legs together to form a solid unit, making sure that it fits tightly around the shaft tube!!
THEN; when the shaft tube is correctly fitted in the hull and everything is cured cut a slot to fit the bracket into the hull and epoxy it in. Fill and smooth on the outside as needed. Looks better and lasts longer 😉
Again, see the Belfast pic. Cheers Doug 😎
So ends the 17th epistle from admiral Doug😉 Hope it helps!

Hi Neil
Just about to go out so short reply
Your shaft is 1 1/4" above the hull bottom, so almost 1/2" too high from the hull.
If your rudder is 1 3/8" from the stern this will be ok and I would leave it alone for now. Block up the skeg hole.
Yes 3 1/8" is the distance from the stern to my shaft.
You need to measure the distances from each sides of your hull to find the true centre and mark this on the hull. I am not convinced your shaft is truly square. it needs to be equidistant from each side.
If you open up the slot in the hull you will be able to position the shaft correctly in line and at a shallower angle. As long as there is room to fit the prop the shaft can be positioned nearer the rudder. if there is still room inside the hull to fit the coupling and motor then the longer shaft may be OK.
Sorry have to go. Back later today so please ask if you need more guidance.
Don't worry too much about making the slot too big, you can repair with filling once the shaft is correctly placed.
Cheers
Dave

Hi Dave

Thanks for taking the time to take those measurements which has given me something to compare against which is greatly appreciated. Now for the return and more questions😁

The rudder centre is positioned at 1 3/8" but the water pick up is at 2 3/8" and more centrally positioned so I presume I should be looking at blanking off the rudder and using the water pick up as the rudder position?
Also presume on the first photo I have the correct understanding on how you took the measurements to achieve a shaft position of 3 1/8"?

On the shaft to the hull I'm at 1" so some more sanding to do at the weekend also noticed that the hole is no longer symmetrical which is were your tooth pick comes in the ensure it is fixed centrally on the hull😁😁

The outer tube for the shaft is 10" which is somewhat longer than yours 😲 and if I was to replicate your working build it is obviously wise to purchase a shorter shaft with the added benefit of providing some flexibility when fitting the motor?

Also thinking my need to purchase a new skeg as I think it may snap if it was to be re bent to fit the repositioned shaft tube?

Sorry for more questions but this has stopped me doing anything for a year as I had no idea what I was doing. Now with the guidance from you and Doug I may just get it right 👍

Agreed👍 I had forgotten to ask if he really needs the water scoop; i.e. for water cooling motor and/or ESC. Or for the Fire Monitor ??
If not; get rid of it!
Like the 'cocktail stick alignment aid' 👍👍
Good luck Neil, cheers Doug 😎

Hi Neil
I have just been and measured my 34" Fireboat.
The shaft is 8" long. in situ it is 3/4" below the hull bottom and 3/4" above the hull inside. inside the hull the shaft rests on the former aft of the original engine space The prop is a 30mm 3 blade brass.
My rudder is 2" in from the hull stern. The shaft is 3 1/8" inches from the hull stern.
My skeg below the hull is 1 1/4" deep as this was on the original hull I renovated. it finishes 3" from the hull stern.
If you haven't already I suggest you remove the water scoop and fill the hole with dowel and filler.
I agree with Doug, leave the rudder in place if the distances are similar to that I have given. Looking at your pic it would seem you will be able to raise the shaft and still have room. To do this you need to cut the shaft hole towards the stern so the shaft can be closer. Do make sure the shaft is in the centre and straight and not aligned to the off centre rudder. A small hole aft of the rudder on the centre line with a cocktail stick may help. The water pickup is about the right distance below the hull but needs removing.
You do need to check inside the hull to see that there is sufficient height on the prop tube to allow for alignment with the motor and base. This is just a check, the motor can be fitted and aligned later.
Looks like a nice claen hull
Cheers
Dave

👍 Sweet dreams zzzzzzzzzzzzzz 😊
Good night from Munich, Doug 😎

I think you're starting to understand how much of a novice I am to this game as simple advice is good for me, as a few thousand pounds worth of pennies has just dropped for me 😂😂😂
I thought it was all done together shaft motor mount etc 😂😂😂😂😂😂
Cheers Doug I may even be able to sleep tonight now knowing the task has just become so much simpler 😉

Good👍😉
The shift it forward of the intake pipe fix and fill it and leave it to cure!
THEN fix the motor mount!
The motor mount can always be adjusted without having to rip the hull open like for changing / moving the prop shaft. 😊 A problem I currently have with my Graf Spee😭 Doug 😎

No luckily I was using the pick up tube as a reference point to show in the photo what had been achieved from yours and Dave's advice 😁
I haven't even contemplated making it permanent yet as the motor now needs support alignment etc. To be honest it's all a little much.
The replacement shaft I purchaed was a direct replacement for original shaft so no reference was made to the plans. I was content to struggle aligning the motor and shaft with the original IC mount and then just gave up till now lol.

Oh no! I hope you haven't glued and filled it yet😡
If so you're gonna have to cut/break it out again move it forward and adjust the motor mount accordingly.
Frankly the length of Dave-M's shaft (😲) is irrelevant. That depends on where he wanted to mount the motor and the length of the coupling he used. What you should have done is-
1 Check the length on the plan before you ordered,
2 Check alignment and position of the prop end relative to rudder etc BEFORE fixing it permanently.
Back to the drawing / hacking board 🤔
Cheers Doug 😎

I think I've achieved what was needed as the shaft position is less acute now but I have noticed a few more issues I think.

1. The rudder bearing tube and water pick up don't seem to be positioned correctly - separate post on this one.
2. Looking at the plans the shaft tube is about 2 inches longer than the one in the plans.

Dave M what length of boat shaft is fitted to your Crash Tender?

Yes it does but there is a cover over the shaft so you can't see the whole train. it is all square and true and needsss to be - the original motor worked loose and self destructed😭.
I just used this old photo to show the distancing so hopefully it served its purpose.
As regards the tacking I don't believe we are suggesting anything different and regardless of the age of the aperture the principle is the same.
Still no wind so will have to be the "Searcher" Customs cutter sailing
Dave

Hi Dave, Yep, agree, tacking works with a virgin shaft hole. But here we were talking about re-positioning so there are larger gaps to fill than usual. The wedges help to keep everything steady on the keel line.
In your pics 2, 3 and 5, with the blue motor, looks like there is a slight 'tilt' of the motor to port! Maybe the camera (or my vari-focals!) lied. 🤔
have a good day all, cheers Doug 😎

Hi Doug
My suggestion was to fit and tack the shaft in place ie not try and fill the whole joint until it was all aligned.
I prefer Plastic Padding as there is less chance of misaligning the tube, but either method works.
Not sure which pic you are referring to?
Cheers
Dave

Hi Dave, can't quite visualise how the 'couple of dabs of super glue' shall be applied in the air!😲
I use the shaped balsa wedges to achieve the alignment and THEN glue and screw everything down before it can move!
Doug
PS That might account for the misalignment I noticed in the pics you posted above!

Thanks both Doug and Dave

I do have a couple of different mounts which were purchased to try and get round my sticky motor which initially proved to the glue holding the shaft had failed causing vibration and the old diesel mount causing misalignment. I have just recently even purchased a plastic type mount like the one you have Doug😉

Should have removed the mount when you suggested it a year ago Dave but a little scared now I can start a fresh. Now thats done and new lease of life should see me busy at the weekend. Little concerned on the hungry and smelly motor but like the idea of a Lipo with Tamiya connector will have a look for those later.

Was a little worried about drilling through but like the idea of dowel and sand paper nice and easy I think until I get bored and then probably resort to the drill lol.

Thanks for all the advice and the confidence you guys give. Ill update my year old blog with progress over the next couple of weeks.😁😁

Hi Neil
Just seen your post re a 34" Crash Tender. The pic you posted looked like the bigger version.
Your model is the same as mine as per the earlier pics.
This is a small (by my standards anyway) model and works best with a light power train set up.
I have a small 22xx brushless with a 30amp car ESC and 11.1v LiPo resulting in a very light model that positively leaps onto the plane.
The 600 setup you have should work well but at the cost of a heavy overall weight. it is a very power hungry motor and if you overload it with too big a prop you will be able to smell the motor cooking on the lake, don't ask how I know!
Regarding the hole, yes drill holes and file the slot to suit the angle. if you get a piece of dowel slightly smaller than the prop shaft you can wrap some coarse sandpaper round the dowel and use it to file the slot. Fit the prop/shaft/prop/coupler and motor and tack the propshaft in place with a couple of dabs of superglue. When set check that all is square and aligned and fill the gaps between shaft and hull with slivers of balsa and E$poxy glue. I use Plastic padding bu8t either will do. When dry sand smooth to shape.
You may already have a mount for the 600 motor but SHG sell suitable mounts.
You can easily convert to brushless and LiPos in the future. I agree the initial cost is high as you will need Charger, motor, ESC and Lipo battery but there are good cheap motor and ESC combinations that won't cost as much as you are expecting and you can use NiMh (NiCads are no longer used) batteries to avoid the extra cost of LiPo and charger.
Happy building
Dave

Sorry Neil, when I wrote all the blurb above about motor mounts I didn't know you had a 600 brushed. Then you would need the 600/700/800 version of the motor mount I described. Don't know the part number but I've seen it on the Krick site. http://www.krickshop.de/?shop=krick_e
Cheers Doug 😎

Hi Neil, Freut mich! As they say around here. (Glad about that!)
Clever lady! Greetings to the Boss 😊
BTW; I added some extra comments about the battery, possible LiPo, lighter weight would provide even more capacity and longer running times!
Whatever you do have fun with it, and enjoy the dinner 👍😉
All the very best, Doug 😎

Good advice on all points there Doug the Boss likes the single candle lit dinner as it would be cheaper than buying both clever lady.
My boat is the 34 inch version so the smaller of the two Crash Tender versions but like the suggestion of changing battery as when I actually get to sailing it wouldn't want wet feet straight away😜

Aye aye sir! Message received and understood! 👍
Go with what you have first. Don't look bad, but you have a pretty big boat there! One thing; NiCad 😡 that's a No No these days, at least swap it for a NiMh. For such a big boat and thirsty motor I would probably go for at least a 5000mAh. Aboat that size can surely carry it. Otherwise you could try a lightweight LiPo 2S = 7.4V. IF the ESC is declared as 'LiPo safe', then it shuts down when the cell voltage reaches the minimum, usually set 3.0 or 3.2 volts. A decent modern 2.4Gig RC set (e.g the Turnigy i6) will tell you the battery voltage by telemetry back to the TX display! 😉
If you ain't happy with the performance an upgrade may well cost you a candlelight dinner .... on top of the 80 quid! 😲😉😉
Let us know how it goes (the boat I mean 😁)
Cheers Doug 😎

Hi Doug, some amount of information to digest on this but I think I'm getting it some head scratching and hard work to come😁
Regarding motor replacement - love the idea of gold plated but when I take a motor, ESC and battery into the equation its about £80+. I currently have a Graupner Speed 600 7.2v motor, Ripmax Xtra Quantum ESC and a Tornado 3800mAh NiCad battery so would need to replace the lot from what I can see with limited knowledge in this area also.

Hi Neil, yes, very similar. Could be regarded to as a first step before applying Eze-Kote to give it a harder, knock and almost everything else resistant surface. Hammerite then sticks to it like the proverbial to the blanket and you have a super clean 'engine compartment' dead easy to keep clean. 😊
80 quid for a brushless !!! Do you want it gold plated or what?
My Propdrive 2830 cost less than 20 knicker from Hobbyking and was delivered almost before I ordered it! Just make sure it comes from the UK or EU (still!?🤔) warehouse and not USA or Global. otherwise you might get stuck for import tax 😡

For the motor mount / shaft alignment: no one said it was easy, but Nothing's Impossible', maybe that's why I drive Toyota!!😁
back end is determined by the diameter of the prop you want to fit, which in the case of brushless motor should be roughly the same diameter as the brushless (outrunner). in my case 28mm motor and 30mm prop.
This defines how far you can lift the aft end of the shaft, leave at least 1cm between the prop tip and the hull! This reduces unwanted interaction between the vortex from the prop and the lamina flow along the hull, result; more forward thrust and better rudder effect.
(Didn't spend 30 odd years talking to shipyards for nowt😉)
If you have plan (or at least a sketch - take some measurements if you don't have one of these and make a sketch) of the keel and existing motor mount; project back from the newly determined exit point of the shaft.
Check how far forward you need to go to be able to comfortably fit the motor mount with good alignment and purchase a shaft of appropriate length. Cut a wood block to fit around the keel as the basic mount and 'fiddle' with it until your motor and mounting (e.g. the Robbe / Romarin 400 mount) aligns with the shaft line. Alignment is checked by running the motor at a fixed low speed with an ammeter showing the current it draws. Shim the motor mount up / down, and shift slowly from side to side until the current reading is a minimum. Then glue and screw everything in place quick before anything moves!
Takes almost longer to describe than to do😉
The coupling type shown in my photo is called a 'Steg' coupling here in Germany (don't know the English🤔) and available from Krick Modellbau, for various motor shaft / prop shaft diameters, here the link to their English page-
http://www.krickshop.de/?shop=krick_e
Part number for the 3.17mm (1/8") to 4.0mm version I used is 63902.
part number for the motor mount I used for my 28mm brushless is 42117.

Advantages (to me at least!) they are not as long as the traditional UJ and Cardan types, they are resilient but don't flop about like the UJ types so are much easier to fit and align. Cos they are shorter you can use 'em for mountings in confined spaces. And they don't make no noise!! 😉

One final tip (may not be so useful on hard plywood built boats!).
When I had this problem with my destroyer I sharpened the end of an 8mm alu tube (same as the shaft tube dia) and used it to bore back from the hull exit to the last bulkhead before the motor mounts. the bulkheads though were 1/4" balsa! Nice and soft man 😉
Hope this helps more than confuses, but it all worked for me!
Cheers and happy fiddling, Doug 😎