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[Bradley]

Hi Martin,

Many thanks for your latest info.   I see that you also have fitted trim tabs.

Derek.

[bugs]

Hi Derek

The ESC's are Danlions 100AMP which have reverse as well.  I got them from Astec.  They are programmable but work perfectly well on the standard factory settings.  I built the internals and deck to fit the GRP hull so it is a bit wider than scale.  There is a hollow in the moulding, port side towards the bow which I did not see until it was painted.  If it's not too late have a look for it.

I have to admit I do not know how to attach photos on this forum?

Cheers

Martin

Is that a Tony Abel IOM in the background? (Sorry to be nosey...)

[model boat martin]

Hi

No it's a Lion built from a Graham Bantock plan

Cheers

Martin

[Bradley]

More advice, please, Mayhemmers.  Do I instal the prop shafts in line with the centre of the lowest point of the 'V' of the hull or in line with the two lower spray rails?  Hopefully you will be able to see from the photo that I have marked two lines each side of the hull as a guide to making the holes for the shaft and the lines following the spray rails diverge from the ones following the bottom of the 'V'.  Hope this makes sense.

Derek.

[Bradley]

Further to the above posting.  The outer lines are the proposed position for props, etc.  The two inner lines were marked as a consideration but I decided that they were too low in the hull and too close together.

Derek.

[Bradley]

The cross markings on the fore and aft lines are my proposed positions for the rudders/water scoops/props.  These are (from the transom) - Rudder shafts - 30mm, water scoops - 45mm, prop bosses - 55mm.  I think I am happy with these measurements it is just the fore and aft line-up I want to make absolutely sure of before drilling holes.  The prop shafts will go through tubes that will be only just protruding from the hull and the after end of the shafts will be supported by 'P' brackets.

Derek.

[HS93 (RIP)]

I think you may find the props are a bit far back and spacing a bit close but I know pictures from that angle may not show the true distance. and if you look at the build from Ramon he had a lot of problems with handling with them so far back, anyway I have enclosed 3 pictures that may help you  make neat holes in the right place first time and you can also include the rudder and pickup and test for things like being able to remove prop and if you make it long enough you can check to see if you have clearance for your motor and mount then lay it on the Hull and get things spot on with nice tight holes.Just a thought

peter

[John W E]

Hi there Derek

A rough guide to the centre of the props.   If you take the distance from the centre of your keel to your chine spray rail - divide this distance in half.  This should give you the rough centre for your prop shaft.   The measurement is of course made at the stern of the hull (the widest part) - for arguments sake, say, the distance between the centre of your keel and the chine spray rail is 100 mm  -  so therefore the centre is  50 mm - and this 50 mm centre is parallel to the centre of your keel for the length of your hull.

To get the angles of the prop shafts it would be handy if you had a plan which shows the side profile and then you could calculate from the plan, the angle of the prop shafts.

If you are going to fit a 'P' bracket to support your prop tube as HS93 has shown in his photographs, it is adviseable to cut the slots for your tube slightly larger in the hull, thus allowing for slight adjustment.

If you have a look at the Type 42 build in warships - you will see where I have used a jig to maintain the centre of the props.   What is not shown is that there is a similar jig on the inside of the hull; to support the inner board prop tubes.

The other thing is, you can make a little jig up for the angle of the prop tubes, similar to what I did on the Fairey Swordsman build - that is in the Masterclass/plans for the beginner on this forum.  You will see how I made a temporary jig up out of a piece of plywood; and then tacked it with superglue to the proptube.

aye
johne
bluebird

[Bradley]

Many thanks, Peter and John.  That has certainly given me some ideas to work on.   So far as positioning of the prop in relation to the stern is concerned, I was working on a photo that I have of the full size Huntsman combined with a little 'guestimation'.
Every little helps.

Derek.

[red181]

Hi Derek,
mine is :
Distance from end of hull to rudder post centre = 50mm
Distance from end of hull to water pick up        = 75mm
Distance from end of hull to end of propshaft    = 110mm

These where all original Veron settings, the distance from Hull to shaft centre at tip, to create angle is 23mm, this was reduced from original IC setup to lower cog, minimise distance between prop blade tip and hull, so boat goes straight, and not try and go up! if you know what I mean

The boat turns nice, it "cuts"the water instead of skating over it, and planes just right (so far!). Ramon got to this point, then didnt do anymore, pity as his build was superb, but I personally think his handling problems where due to the prop being too far back, tool far forward and it might not plane, hope this helps

[HS93 (RIP)]

Hi Derek the picture with the supports is just to show you how you can get the position right without making holes whatever p bracket you use you can do it this way just a bit of card plasticard of ply will do if you do make this type of bracket make the plate that finishes flush with the hull very thin so as not to interfear with the water flow I slotted mine so they could be slid in to position when I got the hight right from the hull, the disks with the maximum size of prop you will req are handy as its easy to suddenly find you cannot get the props of your choice on..

Peter

[Bradley]

Many thanks, Paul (Red181).  I now wonder whether I should go along with your measurements for prop positioning, etc. 
Many thanks, Peter (HS93).  I like your idea of a template and will probably have a go at doing something similar tomorrow. 

I have even risked things and drilled pilot holes on my measurements but that will be no problem if I change them as they can be filled and the underside will be the only part of the hull to be painted (I hope) to resemble the antifouling.

Once again, very useful bits of info and much appreciated. 

Derek.

[red181]

Pic of underside Derek, its not a very good one unfortunately

[Bradley]

Thanks, Paul.  That's fine - just gives me some idea of your set-up.

Derek.

[Perkasaman2]

Aligning/installing the motor/shafts/rudders etc. is by far the most fiddly, frustrating ‘fun‘  .  It’s a pain with a ready made wobbly grp hull and you have precut internal frame structure to modify - it’s much easier when you scratch build the hull from a plan - you can decide/pencil in alignment on the side elevation of the plan and extrapolate on the relevant structure/frames - all/every measurements to hand.  
I'm assuming you have chosen motors/mounts and prop size (allowing extra clearance for fitting bigger props?) I used long dowel rod as substitute and splinted it ,including the coupling, onto the mounted motor(s) - I used sleeving/matchsticks/electrical tape - straight n' true. I then decided on my parallel (or splay) dimension and made a couple of temporary symmetrical frames/formers profiled to mount a) one for under the stern b) one for in the hull - both centred on the corresponding hull marks. (I cut these aligning frames out of thick cardboard, notched to locate/ensure parallel or splay of the shafts and maintain their equal symmetry/positioning. I used cellotape for temporary fixing - the cut and fit of the formers proceeds until the alignment/clearance of the assemplies suits/meets all criteria. Cutting/elongating slots through the hull for the shafts needs care and the rear of the boat's cradle may need to be modified to accomodate the protruding shafts.
It’s much easier to strap/support the bare wobbly hull into the cradle minus the internal framing and align the motor shaft assembly  first - then cut n’fit the modified internal structure later. Offset rudders allow shafts/props to be removed easily and enable easier/more effective  positioning of cooling venturi pickup fittings if needed. I found that the last measurement I obtained was the actual length of the propshaft - either choose nearest size/tweak installation   or cut n’ file a pair.
I ‘resinned’ baseplate(s) on hull bottom and countersunk vertical mounting bolts for fixing engine mounts then shimmed each corner of the mounts with various washers to ensure straigt n' true alignment with  released couplings.  
Apologies  if I’m droning on to the initiated but none of the above was obvious to me - I ended up with a hull like swiss cheese  - I can look back and laugh now   - Less pain more gain!  

[DickyD]

Perhaps if you used/employed one word instead/in place of two all the time your posting/reply would be easier to read/understand Mr Perkasaman. 

[John W E]

Hi ya there Derek

I have just done a web-search for the Huntsman and these are some of the photograph I have found showing the prop positions - of the fullsized Huntsman.

It does look as though the prop shaft line is slightly closer to the keel; but, I do hope these are of some help.

aye
john e
bluebird

[Bradley]

Hi John,

Many thanks for the photos - I did not manage to find those when I was Googling.  I think that I am happy with my 'guestimation' for positioning although the set-up for my props, etc., will be slightly further apart than on the full size.

Derek.

[SteamboatPhil]

Is it me, but it looks like both props are going anti clockwise ? I thought they would counter rotate.
How will you be doing yours Derek ?

[Bradley]

Hi Phil,

Couldn't really see from the photos what 'handed' the props were.  I intend fitting a right handed prop to the starboard shaft and left handed to t'other.

Derek.

[Flying Sparks]

Bluebird, on those pictures of the Huntsman that you posted do you know what the extension below the stern tube brackets are for?

[John W E]

Hi there Flying Sparks
The extensions on the bottom of the ‘P’ brackets are rope cutters.  These are there to try and prevent the propellers from being fouled and also to give some protection against the tips of the blades on grounding.
Aye
John e
Bluebird

[Perkasaman2]

Divvent fret wor Dicky - jus reed slowa man! 

[red181]

Great pics Bluebird, those extensions on the bottom, bet they would have helped Ramon with his handling problems?

[DickyD]

Is it me, but it looks like both props are going anti clockwise ? I thought they would counter rotate.
How will you be doing yours Derek ?

You're right Phil, both props are the same hand.