Reply
 
Thread Tools Search this Thread
 
Old 16 January 2006, 11:12   #1
Member
 
gtflash's Avatar
 
Country: UK - England
Town: southampton
Boat name: TOP CAT 2
Make: Scorpion 8.1
Length: 8m +
Engine: 250hp HO
Join Date: Aug 2003
Posts: 1,496
scorpion hull stats

does anyone know the stats on a scorpion hull, whats its dead rise at transom, midship and bow.. will help settle a friday nite squable..

thanks gt
__________________

__________________
gtflash is offline   Reply With Quote
Old 16 January 2006, 12:09   #2
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,869
Quote:
Originally Posted by gtflash
does anyone know the stats on a scorpion hull, whats its dead rise at transom, midship and bow.. will help settle a friday nite squable..

thanks gt
Must be a right laugh, having a beer with you guys.
__________________

__________________
Mollers is offline   Reply With Quote
Old 16 January 2006, 15:18   #3
Member
 
Country: UK - England
Town: Solent
Length: 7m +
Join Date: Jul 2005
Posts: 34
I would think that 'Searider' is the man for this sort of thing. He should be able to help you out.
__________________
Live the Brand!
moresauce is offline   Reply With Quote
Old 16 January 2006, 15:19   #4
Member
 
Country: UK - England
Town: Solent
Length: 7m +
Join Date: Jul 2005
Posts: 34
Quote:
Originally Posted by Mollulnan
Must be a right laugh, having a beer with you guys.

Yeah, good point, favourite pub conversation on a Friday night has to be, top ten film breasts!
__________________
Live the Brand!
moresauce is offline   Reply With Quote
Old 16 January 2006, 15:35   #5
Member
 
Country: UK - England
Town: Southampton
Boat name: SMH Rib / War Shot
Make: Ribtec / Scorpion
Length: 4m +
Engine: 10hp Yam / 150hp opt
Join Date: Sep 2003
Posts: 1,944
RIBase
Deep at the stern.

Very deep at the bow.

Deeper than most and very narrow waterline beam.

To dark and windy to go outside with my protractor and tape measure!
__________________
Searider is offline   Reply With Quote
Old 16 January 2006, 15:43   #6
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
Quote:
Originally Posted by gtflash
does anyone know the stats on a scorpion hull, whats its dead rise at transom, midship and bow.. will help settle a friday nite squable..

thanks gt
Willing to bet the deadrise at the stern is a convex curve rather than single angle.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 16 January 2006, 15:45   #7
Member
 
Country: UK - England
Town: Southampton
Boat name: SMH Rib / War Shot
Make: Ribtec / Scorpion
Length: 4m +
Engine: 10hp Yam / 150hp opt
Join Date: Sep 2003
Posts: 1,944
RIBase
Quote:
Originally Posted by Pete7
Willing to bet the deadrise at the stern is a convex curve rather than single angle.

Pete
Have a green blob Pete.
__________________
Searider is offline   Reply With Quote
Old 16 January 2006, 16:06   #8
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
Oops be accused of rib spotting again
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 16 January 2006, 21:35   #9
Member
 
gtflash's Avatar
 
Country: UK - England
Town: southampton
Boat name: TOP CAT 2
Make: Scorpion 8.1
Length: 8m +
Engine: 250hp HO
Join Date: Aug 2003
Posts: 1,496
QUOTE=Pete7] Willing to bet the deadrise at the stern is a convex curve rather than single angle.

Pete [/QUOTE]

sorry pete you lost me there!! can you explain

and the best breasts and tightest hot pants conversations usually start once were out the dingy local and at first sign of lady flesh!

later in evening conversation revolves around best kebab in soton and garbled messages about something we can never remember
__________________
gtflash is offline   Reply With Quote
Old 17 January 2006, 03:41   #10
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
Sure, I have taken a page out of the JW bible and drawn a quick diragram which might help explain. The Scorpion hull rather than having flat panels to the hull is actually a compound curve. Looking at the stern you will see that the deadrise rather than being a straight line is a gentle convex curve shape so its steeper towards the outside of the hull and shallower at the very bottom of the hull. Making the hull angle shallower at the bottom will help to produce lift particularly at the stern. I think you could describe the hull shape as "delta conic" which is interesting because although the Scorpion hull shape was drawn by a professional naval architect David Marsh in about 1995 it is very similar to the Osprey XR24 which started production 3 years previously. Even the advertising at the time which included a line drawing of the hull shape looked like an XR24 and used the same moulded deck system. Possibly just a similarity, but its sure to have Scorpion owners jumping up and down in protest

Pete
Attached Thumbnails
Click image for larger version

Name:	Scorpion hull.JPG
Views:	142
Size:	10.3 KB
ID:	17046  
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 17 January 2006, 04:25   #11
Member
 
Country: UK - England
Town: Southampton
Boat name: SMH Rib / War Shot
Make: Ribtec / Scorpion
Length: 4m +
Engine: 10hp Yam / 150hp opt
Join Date: Sep 2003
Posts: 1,944
RIBase
Nice drawing!

It's a bit like that but its two curves that still meet in a point at the bottom.
Can't work out how to do drawings though.

I wonder if the vee of a Scorpion is deeper at the bow than the Viper - I don't think the Scorpion is as fast as some other 6.5m boats and this could be one of the factors.
__________________
Searider is offline   Reply With Quote
Old 17 January 2006, 04:43   #12
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
Quote:
Originally Posted by Searider
Nice drawing! It's a bit like that but its two curves that still meet in a point at the bottom. Can't work out how to do drawings though. I wonder if the vee of a Scorpion is deeper at the bow than the Viper - I don't think the Scorpion is as fast as some other 6.5m boats and this could be one of the factors.
Thanks drawing was done in MS Paint because I don't have anything else at work.
If you look directly at the nose of a Scorpion the bow has an astonishingly deep V shape and is a very fine almost knife like shape, both the Viper and XR24 are much fuller. Be interesing to measure it sometime but I would guess at 60 degrees. Whether this produces a better hull is probably subjective and would depend on what the rib was being used used for. Certainly the very fine bow ought to be good for cutting though that horrible Solent chop created by all those dreadful speed boats that clutter up our waters.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 17 January 2006, 06:08   #13
Member
 
gtflash's Avatar
 
Country: UK - England
Town: southampton
Boat name: TOP CAT 2
Make: Scorpion 8.1
Length: 8m +
Engine: 250hp HO
Join Date: Aug 2003
Posts: 1,496
i suppose the constant curve and lack of flat surface increases strength too.. used to be one guy on this forum that constantly shouted that scoprs stuff easily unsubstantiated.. however with a fine bow and deep aft it must make them more ideal for head seas than following (ps i love scorpions and their ride all owners )does the xr24 have this gentle convex too?? anyone know the actual deadrise at transom on scorpion?
__________________
gtflash is offline   Reply With Quote
Old 17 January 2006, 07:44   #14
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
The Original XR24 did have a "delta conic" hull however Osprey modified it early on with a huge flat planning wedge tapering to a point about half way along the keel. They also removed the flooding hull which owners didn't want. This produced a light weight 24 foot rib capable of high speeds with a 1/2 tonne payload which remains a very competent hull today, well IMHO.

The deadrise of the Scorpion is variable so not sure how you could measure it at any one point and produce a meaningful measurement to compare it to a hull with flat panels.

Quote:
Originally Posted by gtflash
make them more ideal for head seas than following
possibly but most Scorps I see out and about are lightly loaded & have good power to weight (just a few crew) rather than say a heavily loaded dive boat so more likely to rise to / power over a following wave. They are also very expensive so owners likely know what they are doing and take care and pride in there ribs rather than the forgotten and forlorn club rescue or dive boat.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 17 January 2006, 10:04   #15
Member
 
Country: UK - England
Town: Southampton
Boat name: SMH Rib / War Shot
Make: Ribtec / Scorpion
Length: 4m +
Engine: 10hp Yam / 150hp opt
Join Date: Sep 2003
Posts: 1,944
RIBase
Quote:
Originally Posted by Pete7
owners likely know what they are doing and take care and pride in there ribs
Pete
Flattery will get you everywhere.

Have only driven my 6.5m Scorpion but can confirm that the fine bow is great in a head sea.
It does tend to put its nose in the air a bit but maybe this is because you can drive quite hard up sea and are bound to catch a bigger one every once in a while.
Observing larger Scorpions they seem to do the same.

Never stuffed mine - but tend to be careful going downwind.

The only downside of the very fine bow that I have experienced is that if you are going diagonally across the sea and don't land level (athwartships) the bow can hook causing the boat to steer off to one side. Have nearly fallen out twice doing this.
Once by accident on the way to Weymouth, the first time my Brother had driven it, and once when driving "enthusiastically" over the wake of a ship to see what would happen. Think I'll slow down a bit going over ships wakes in future

Would be interesting to see what a larger one is like to drive. Must work harder and save some pennies.
__________________
Searider is offline   Reply With Quote
Old 17 January 2006, 12:56   #16
Member
 
Country: UK - Scotland
Make: HumberOceanOffshore
Length: 8m +
Engine: Volvo KAD300/DPX
Join Date: Oct 2002
Posts: 5,362
Quote:
Originally Posted by Searider
The only downside of the very fine bow that I have experienced is that if you are going diagonally across the sea and don't land level (athwartships) the bow can hook causing the boat to steer off to one side. Have nearly fallen out twice doing this.
Yeh, that can be vicious. Searider, make sure you have no play in the steering and engine mounting(s) and/or bearings. If you have no play and it still does that....oooww.


Pete7, is it gen that the hull is a continuous curve on each side?
__________________
JW.
jwalker is offline   Reply With Quote
Old 17 January 2006, 13:20   #17
Member
 
Hugh Jardon's Avatar
 
Country: UK - England
Town: Reading, Hants
Boat name: Juicy
Make: Sealine F43
Length: 10m +
Engine: 2 x 370hp
MMSI: TBC
Join Date: Sep 2005
Posts: 2,882
Quote:
Originally Posted by Pete7
The Original XR24 did have a "delta conic" hull however Osprey modified it early on with a huge flat planning wedge tapering to a point about half way along the keel. Pete
and here is an example of the flat planning wedge
Attached Thumbnails
Click image for larger version

Name:	DSC01949.JPG
Views:	135
Size:	130.2 KB
ID:	17056  
__________________
Hugh Jardon is offline   Reply With Quote
Old 17 January 2006, 14:07   #18
Member
 
Country: UK - Wales
Town: Southampton
Boat name: DynaMoHumm/ SRV/deja
Make: Avon8.4, 5.4 & 4.777
Length: 8m +
Engine: Cat3126 Yam 90 &70
MMSI: 42
Join Date: Dec 2003
Posts: 6,559
Quote:
Originally Posted by Searider
.



The only downside of the very fine bow that I have experienced is that if you are going diagonally across the sea and don't land level (athwartships) the bow can hook causing the boat to steer off to one side. Have nearly fallen out twice doing this.
Once by accident on the way to Weymouth, the first time my Brother had driven it, and once when driving "enthusiastically" over the wake of a ship to see what would happen. Think I'll slow down a bit going over ships wakes in future

.
firstlys your brother is a bit of a headbanger behind the wheel, he hearly went faster than me once in you Avon 5.4.

Re the hook problem it can be nasty, however there is a real cool technique which takes the problem away without speed reduction. I can't be arsed to explain it here but I'd be delighted to show you!
__________________
Here it comes again, I don't stand a chance
Soul possession, Got me in a trance
Pullin' me back to you - Deja Voodoo
Rogue Wave is offline   Reply With Quote
Old 17 January 2006, 16:34   #19
Member
 
Pete7's Avatar
 
Country: UK - England
Town: Gosport
Boat name: April Lass
Make: Moody 31
Length: 9m +
Join Date: Aug 2001
Posts: 4,899
Quote:
Originally Posted by jwalker
Pete7, is it gen that the hull is a continuous curve on each side?
JW, the curve isn't immediately obvious. with a straight edge against the transom the curve is about 2 inches out at the widest point. The bow looks almost flat so whoever made the mould must have had some fun.

Pete
__________________
.
Ribnet is best viewed on a computer of some sort
Pete7 is offline   Reply With Quote
Old 17 January 2006, 17:00   #20
Member
 
gtflash's Avatar
 
Country: UK - England
Town: southampton
Boat name: TOP CAT 2
Make: Scorpion 8.1
Length: 8m +
Engine: 250hp HO
Join Date: Aug 2003
Posts: 1,496
had a look at scoprion hull today, ur right pete about the continuous arc.. but im trying to make up my mind what the advantage is, i presume a curved surface is stronger than a flat one but wouldnt increase surface area?? would that not make it less efficient and more slammy than a straight line type varying deep v
__________________

__________________
gtflash is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 16:23.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×