Re: Liftable Drive System you can build for a Bolger power sharpie
You guys should read what the article already has written. It says
that the ratio is 2 to 1 with the use of pulleys and a drive belt. I
know with my wood lathe I have a set of slide pulleys I use to
reverse rotation when I use my router to carve reverse designs. So
reversing the drive shaft with pulleys and drive belts is not beyond
contemplation.
I sent the letter last week so short of what we now know everything
is speculation. They have said that anybody with a workshop with
lathe and welding machine can make the liftable drive unit. We'll see
when the plans come back.
John
that the ratio is 2 to 1 with the use of pulleys and a drive belt. I
know with my wood lathe I have a set of slide pulleys I use to
reverse rotation when I use my router to carve reverse designs. So
reversing the drive shaft with pulleys and drive belts is not beyond
contemplation.
I sent the letter last week so short of what we now know everything
is speculation. They have said that anybody with a workshop with
lathe and welding machine can make the liftable drive unit. We'll see
when the plans come back.
John
--- In bolger@y..., "rnlocnil" <lincolnr@m...> wrote:
> There's always reduction gearing, chain, or belt. Homebuilt
airplane
> guys have been doing these in a big way for very much more power
than
> we are usually into, tho smaller ratios.
> --- In bolger@y..., stephensonhw@a... wrote:
> snip
> >
> > A little more info. from the same book: The "retractile" [love
that
> word!]
> > propellor shaft is [was] available from Acadia Gas Engines Ltd of
> > Bridgewater, Nova Scotia. Gardner says that nearly all modern
> engines rev.
> > too fast for this type of shaft arrangement. snip
announcer97624 wrote:
Or, we may still be discussing the FAO design, only mounted on the stern
instead of in a box...
Since I do not have the problems involved with handling nets and
beaching, I would forego mounting the drive in a box and put it on the
transom. Besides a less complicated installation, it seems that
maintenance would be far easier if the drive did not penetrate the hull
in a box. Recessing the drive would push the engine forward, which may
be good for trim. But on the other hand, mounted the the stern the
engine is still farther forward than an outboard. One problem with
extending the drive astern is the rudder. The FAO design handles that
nicely, but four feet astern it could be rather clumsy. I'm hoping that
since the drive is liftable it can also be made steerable like the DBD.
I wish we could see the plans and stop guessing <deep sigh and grin>
BTW, using the magic of vellum and a scale I estimate the shaft on the
FAO plans is a little less than four feet long from pivot point to end,
and it pivots right about at waterline. Whatever that's worth.
Stew
> I think this thread has now been under the misconception that we areOops. Perhaps we have digressed to discussing a homemade DBD drive.
> discussing a long-tail drive.
Or, we may still be discussing the FAO design, only mounted on the stern
instead of in a box...
Since I do not have the problems involved with handling nets and
beaching, I would forego mounting the drive in a box and put it on the
transom. Besides a less complicated installation, it seems that
maintenance would be far easier if the drive did not penetrate the hull
in a box. Recessing the drive would push the engine forward, which may
be good for trim. But on the other hand, mounted the the stern the
engine is still farther forward than an outboard. One problem with
extending the drive astern is the rudder. The FAO design handles that
nicely, but four feet astern it could be rather clumsy. I'm hoping that
since the drive is liftable it can also be made steerable like the DBD.
I wish we could see the plans and stop guessing <deep sigh and grin>
BTW, using the magic of vellum and a scale I estimate the shaft on the
FAO plans is a little less than four feet long from pivot point to end,
and it pivots right about at waterline. Whatever that's worth.
Stew
There's always reduction gearing, chain, or belt. Homebuilt airplane
guys have been doing these in a big way for very much more power than
we are usually into, tho smaller ratios.
guys have been doing these in a big way for very much more power than
we are usually into, tho smaller ratios.
--- In bolger@y..., stephensonhw@a... wrote:
snip
>
> A little more info. from the same book: The "retractile" [love that
word!]
> propellor shaft is [was] available from Acadia Gas Engines Ltd of
> Bridgewater, Nova Scotia. Gardner says that nearly all modern
engines rev.
> too fast for this type of shaft arrangement. snip
In a message dated 6/28/02 10:04:12 PM Central Daylight Time,
announcer97624@...writes:
of the files. The illustrations on the site are more titillating than
illuminating as to the mechanism involved.
Ciao for Niao,
Bill in MN
[Non-text portions of this message have been removed]
announcer97624@...writes:
> I think this thread has now been under the misconception that we areI'm hoping some public-spririted party will post details of the drive in one
> discussing a long-tail drive. Go to this site where it shows the
> underwater portion of the system both in the lowered position and in
> the raised.
of the files. The illustrations on the site are more titillating than
illuminating as to the mechanism involved.
Ciao for Niao,
Bill in MN
[Non-text portions of this message have been removed]
In a message dated 30-06-02 7:14:11 AM E. Australia Standard Time,
stephensonhw@...writes:
propellor shaft is [was] available from Acadia Gas Engines Ltd of
Bridgewater, Nova Scotia. Gardner says that nearly all modern engines rev.
too fast for this type of shaft arrangement. He recommends a 5 hp
single-cylinder gasoline make-and-break-ignition engine produced by Acadia.
It has a bore and stroke of 4.5" x 5". At 550 rpm it will turn a 16" x 16"
three-bladed propellor, driving the 27' dory at 6 knots.
Lunenburg (N.S.) Foundry and Engineering Ltd. made as similar engine,
according to Gardner.
Howard
[Non-text portions of this message have been removed]
stephensonhw@...writes:
> This arrangement looks very similar to the retractable shaft and propellorA little more info. from the same book: The "retractile" [love that word!]
> shown on St Pierre dories in "The Dory Book" by John Gardner. The propellor
>
> and shaft retracted into a well in the bottom of the hull when launching
> and
> retrieving the boat. They were connected via a universal joint to a simple
> two-stroke gasoline engine. But as this book was published in 1978 I doubt
> whether you would now find makers of similar drives or motors anywhere in
> North America
propellor shaft is [was] available from Acadia Gas Engines Ltd of
Bridgewater, Nova Scotia. Gardner says that nearly all modern engines rev.
too fast for this type of shaft arrangement. He recommends a 5 hp
single-cylinder gasoline make-and-break-ignition engine produced by Acadia.
It has a bore and stroke of 4.5" x 5". At 550 rpm it will turn a 16" x 16"
three-bladed propellor, driving the 27' dory at 6 knots.
Lunenburg (N.S.) Foundry and Engineering Ltd. made as similar engine,
according to Gardner.
Howard
[Non-text portions of this message have been removed]
In a message dated 29-06-02 1:04:12 PM E. Australia Standard Time,
announcer97624@...writes:
shown on St Pierre dories in "The Dory Book" by John Gardner. The propellor
and shaft retracted into a well in the bottom of the hull when launching and
retrieving the boat. They were connected via a universal joint to a simple
two-stroke gasoline engine. But as this book was published in 1978 I doubt
whether you would now find makers of similar drives or motors anywhere in
North America.
I've seen drawings of Japanese fishing boats using a similar arrangement.
Howard
[Non-text portions of this message have been removed]
announcer97624@...writes:
> I think this thread has now been under the misconception that we areThis arrangement looks very similar to the retractable shaft and propellor
> discussing a long-tail drive. Go to this site where it shows the
> underwater portion of the system both in the lowered position and in
> the raised. The page shows four boats but the two larger craft have
> the raising drive.
>
>http://www.fao.org/DOCREP/003/W7260E/W7260E02.htm
>
shown on St Pierre dories in "The Dory Book" by John Gardner. The propellor
and shaft retracted into a well in the bottom of the hull when launching and
retrieving the boat. They were connected via a universal joint to a simple
two-stroke gasoline engine. But as this book was published in 1978 I doubt
whether you would now find makers of similar drives or motors anywhere in
North America.
I've seen drawings of Japanese fishing boats using a similar arrangement.
Howard
[Non-text portions of this message have been removed]
I think this thread has now been under the misconception that we are
discussing a long-tail drive. Go to this site where it shows the
underwater portion of the system both in the lowered position and in
the raised. The page shows four boats but the two larger craft have
the raising drive.
http://www.fao.org/DOCREP/003/W7260E/W7260E02.htm
This should clear up the problem. I was looking at the time for a
long-tail drive example when I discovered this United Nations Agency
design that I thought would work very well for a Bolger Power Sharpie.
If you look at these examples you will notice it doesn't stick out
much further than an ordinary inboard.
I still would like to build an Illinois style Bolger and this type
drive system would be the least expensive. It was designed to be used
instead of the long-tailed motors because of the obvious danger when
used with nets. Besides a nice homemade yacht should also have a
unique drive system by the owner/builder.
John
discussing a long-tail drive. Go to this site where it shows the
underwater portion of the system both in the lowered position and in
the raised. The page shows four boats but the two larger craft have
the raising drive.
http://www.fao.org/DOCREP/003/W7260E/W7260E02.htm
This should clear up the problem. I was looking at the time for a
long-tail drive example when I discovered this United Nations Agency
design that I thought would work very well for a Bolger Power Sharpie.
If you look at these examples you will notice it doesn't stick out
much further than an ordinary inboard.
I still would like to build an Illinois style Bolger and this type
drive system would be the least expensive. It was designed to be used
instead of the long-tailed motors because of the obvious danger when
used with nets. Besides a nice homemade yacht should also have a
unique drive system by the owner/builder.
John
--- In bolger@y..., wmrpage@a... wrote:
> In a message dated 6/27/02 11:57:34 PM Central Daylight Time,
> junkmail@m... writes:
>
>
> > And if the Coast
> > Guard includes the drive in overall length it could push some
boats into
> > the next size range and the associated reg's.
> >
>
> If it pushes your LOA to 20' or better, your compliance
responsibilities
> actually diminish, at least according to "Safety Standards For
Backyard
> Boatbuilders" U.S. D.O.T., USCG ... No "safe loading", no "safe
powering", no
> "floatation" and no "capacity label" requirement, all of which
shorter boats
> are supposed to comply with.
>
> The marina fees issue is a different animal altogether.
>
> Ciao for Niao,
> Bill in MN
>
>
> [Non-text portions of this message have been removed]
In a message dated 6/27/02 11:57:34 PM Central Daylight Time,
junkmail@...writes:
actually diminish, at least according to "Safety Standards For Backyard
Boatbuilders" U.S. D.O.T., USCG ... No "safe loading", no "safe powering", no
"floatation" and no "capacity label" requirement, all of which shorter boats
are supposed to comply with.
The marina fees issue is a different animal altogether.
Ciao for Niao,
Bill in MN
[Non-text portions of this message have been removed]
junkmail@...writes:
> And if the CoastIf it pushes your LOA to 20' or better, your compliance responsibilities
> Guard includes the drive in overall length it could push some boats into
> the next size range and the associated reg's.
>
actually diminish, at least according to "Safety Standards For Backyard
Boatbuilders" U.S. D.O.T., USCG ... No "safe loading", no "safe powering", no
"floatation" and no "capacity label" requirement, all of which shorter boats
are supposed to comply with.
The marina fees issue is a different animal altogether.
Ciao for Niao,
Bill in MN
[Non-text portions of this message have been removed]
Here's a question: Would the powers that be count this drive as part of
the length of the boat, or do they just measure the hull? I'm thinking
of marinas, the tax man, and USCG. I've heard of marinas counting
rudders and bow sprits when charging by the foot. And if the Coast
Guard includes the drive in overall length it could push some boats into
the next size range and the associated reg's.
One other thought (I'm full of 'em) is that a long drive may make
med-style docking difficult, though probably not much more so than a
stern drive. But I'm just playing devil's advocate hear. I've long
been interested in the DBD drives. My only question was always why did
I need a drive rated for 350 HP coupled to a two cylinder diesel? These
FAO units sound more appropriate. I can't wait to see 'em.
Stew
aw, I'm not going to the med anyway
the length of the boat, or do they just measure the hull? I'm thinking
of marinas, the tax man, and USCG. I've heard of marinas counting
rudders and bow sprits when charging by the foot. And if the Coast
Guard includes the drive in overall length it could push some boats into
the next size range and the associated reg's.
One other thought (I'm full of 'em) is that a long drive may make
med-style docking difficult, though probably not much more so than a
stern drive. But I'm just playing devil's advocate hear. I've long
been interested in the DBD drives. My only question was always why did
I need a drive rated for 350 HP coupled to a two cylinder diesel? These
FAO units sound more appropriate. I can't wait to see 'em.
Stew
aw, I'm not going to the med anyway
> > 1) Propeller efficiency vs. shaft angle. I believe this dependson
> > the type of propeller.That would be tough to achieve in this arrangment. I would still
>
> Typical is no more that 8 degrees.
>
like to see a graph of efficiency vs. shaft angle to see how bad it
gets. Maybe prop manufactures would have this.
> > 2) How to control whipping in the long unsupported shaft. Thelocated at
> > textbook solution is to use a thicker shaft but that gets heavy.
> > The automotive solution to this is a hollow drive shaft. I have
> > never seen hollow shafts used on a boat. Are they available in
> > stainless steel?
>
> You can use a shaft running inside a tube. Use Delrin bearings
> random spacing of 8 to 12 inches. The random spacing stopsharmonic
> vibrations. Size the pipe at least 1 inch ID bigger than the propshaft.
It seems to me that it would be simpler and more reliable (It would
be hard to monitor wear inside the tube) to just use the tube as the
shaft. Just put connections on the ends and spin the tube.
Well, the web site was in English...
> I only wish I had thought of pre translating the letter before it wassent.
>
Yes HJ, I can scan them and put them on the Bolger #2 site for
everyone. We "third-world" boat builders need all the help we can get
and I am amazed that the big corporations didn't bury those plans
deeper. Magazines like Popular Mechanics and the like get advertising
dollars from the drive makers so a do-it-yourself, affordable and
good sense propulsion unit will never be published openly.
I hope that the people on the receiving end can translate my
request. I will wait a couple of weeks then send another letter in
Italian(a job for my brother in law)to make sure I get the
documentation. I only wish I had thought of pre translating the
letter before it was sent.
John
everyone. We "third-world" boat builders need all the help we can get
and I am amazed that the big corporations didn't bury those plans
deeper. Magazines like Popular Mechanics and the like get advertising
dollars from the drive makers so a do-it-yourself, affordable and
good sense propulsion unit will never be published openly.
I hope that the people on the receiving end can translate my
request. I will wait a couple of weeks then send another letter in
Italian(a job for my brother in law)to make sure I get the
documentation. I only wish I had thought of pre translating the
letter before it was sent.
John
--- In bolger@y..., "Harry W. James" <welshman@p...> wrote:
> Will you be able to digitize it and share it around when you get
it? I
> had a letter typed up and was going to make a trip to the Post
Office to
> get it properly stamped, but I will not bother them if you have it
> coming already and can scan.
>
> HJ
>
Will you be able to digitize it and share it around when you get it? I
had a letter typed up and was going to make a trip to the Post Office to
get it properly stamped, but I will not bother them if you have it
coming already and can scan.
HJ
announcer97624 wrote:
had a letter typed up and was going to make a trip to the Post Office to
get it properly stamped, but I will not bother them if you have it
coming already and can scan.
HJ
announcer97624 wrote:
>
> I have sent away for the information on the drive. From looking at
> the drawings it shows the shaft to be about 5' and it is included
> with the rudder assembly and probably a bearing near the prop. The
> papers fear of larger motors is due to the design inadequacies of the
> boat and not the drive. With a better designed boat a larger motor
> could be incorporated. I have a friend who owns a refrigerated
> trucking company that has a few small surplus diesel engines from the
> refrigerator units. The fuel pumps need to be modified from the
> high/low settings they normally run at so they can have variable
> throttle settings
>
Howdy
----- Original Message -----
Sent: Tuesday, June 25, 2002 10:27 AM
Subject: [bolger] Re: Liftable Drive System you can builfd for a Bolger
power sharpie
> The automotive solution to this is a hollow drive shaft. I have
> never seen hollow shafts used on a boat. Are they available in
> stainless steel?
Automobile driveshafts are just thin wall mild steel, and really not that
much of a precision piece of tubing at that. I would think that any
automotive driveshaft shop that can weld stainless steel can make a drive
shaft out of what ever diameter stainless tubing you can come up with. The
larger the outside diameter the stiffer it will be across it's length.
Good luck
See Ya
Have Fun
Bruce
http://www.cableone.net/bcanderson/
I have sent away for the information on the drive. From looking at
the drawings it shows the shaft to be about 5' and it is included
with the rudder assembly and probably a bearing near the prop. The
papers fear of larger motors is due to the design inadequacies of the
boat and not the drive. With a better designed boat a larger motor
could be incorporated. I have a friend who owns a refrigerated
trucking company that has a few small surplus diesel engines from the
refrigerator units. The fuel pumps need to be modified from the
high/low settings they normally run at so they can have variable
throttle settings
We must remember that this system is the answer that a United
Nations agency came up with to replace the tried and true long tail
system. In Thailand I have seen their home grown step hull speed
boats that use hopped up Toyota and Nissan motors with the regular
longtail drives that will do over 70mph! The drive shaft actually
counterbalances the motor weight and the driver uses a twist grip
throttle like an out board and steers the boat with the same handle
connected to the motor.
After a long day of pushing the shaft and motor around you could get
really tired. If you look through that site you'll find the complete
plans for four boats but as I mentioned they have design flaws that
limit their speed to a snails pace. I don't know how long it will
take to get the design plans for the drive via snail mail from Italy?
John
the drawings it shows the shaft to be about 5' and it is included
with the rudder assembly and probably a bearing near the prop. The
papers fear of larger motors is due to the design inadequacies of the
boat and not the drive. With a better designed boat a larger motor
could be incorporated. I have a friend who owns a refrigerated
trucking company that has a few small surplus diesel engines from the
refrigerator units. The fuel pumps need to be modified from the
high/low settings they normally run at so they can have variable
throttle settings
We must remember that this system is the answer that a United
Nations agency came up with to replace the tried and true long tail
system. In Thailand I have seen their home grown step hull speed
boats that use hopped up Toyota and Nissan motors with the regular
longtail drives that will do over 70mph! The drive shaft actually
counterbalances the motor weight and the driver uses a twist grip
throttle like an out board and steers the boat with the same handle
connected to the motor.
After a long day of pushing the shaft and motor around you could get
really tired. If you look through that site you'll find the complete
plans for four boats but as I mentioned they have design flaws that
limit their speed to a snails pace. I don't know how long it will
take to get the design plans for the drive via snail mail from Italy?
John
> 1) Propeller efficiency vs. shaft angle. I believe this depends onTypical is no more that 8 degrees.
> the type of propeller.
> 2) How to control whipping in the long unsupported shaft. TheYou can use a shaft running inside a tube. Use Delrin bearings located at
> textbook solution is to use a thicker shaft but that gets heavy.
> The automotive solution to this is a hollow drive shaft. I have
> never seen hollow shafts used on a boat. Are they available in
> stainless steel?
random spacing of 8 to 12 inches. The random spacing stops harmonic
vibrations. Size the pipe at least 1 inch ID bigger than the prop shaft.
Use a drill press and hole saws to cut the bearing. Maybe even use a one of
the plastic cutting boards to cut the bearings. Use set screws to lock in
place by just drilling a hole in the pipe and the bearing, use self tapping
screws. Dont' allow the screw to touch the shaft though. Fit a basic seal
like one that's found on trailer axles, probably have to go to an auto store
or surf the net. Nothing special, just enough to keep the water out of the
pipe. Fill the pipe with light oil to lubricate the bearings.
The CC29 that I was going to build used this type of power system on a 10HP
diesel. The shaft was about 12 feet long and attached with a small car
u-joint to the diesel. The other end was lowered and raised with a couple
cables.
Simple and effective and proven.
Jeff
I have been very interested in something like this as a sailboat
auxillary. There are many benefits:
- reduced drag under sail
- no marine growth and galvanic corrosion on prop and hardware
- simplicity of no stuffing box
I've also considered an arrangement with some similar hardware for a
multihull where the motor would be mounted near the front crossbeam
and the prop shaft extends back to a strut near the rear crossbeam.
The prop could be lifted up out of the water when not in use. As
before, no stuffing box, no drag under sail, no growth, etc.
I have been looking for the answers to a couple of questions
regarding this arrangement:
1) Propeller efficiency vs. shaft angle. I believe this depends on
the type of propeller.
2) How to control whipping in the long unsupported shaft. The
textbook solution is to use a thicker shaft but that gets heavy.
The automotive solution to this is a hollow drive shaft. I have
never seen hollow shafts used on a boat. Are they available in
stainless steel?
I think the hardware to do stuff like this is non-standard. Does
anyone know US sources?
auxillary. There are many benefits:
- reduced drag under sail
- no marine growth and galvanic corrosion on prop and hardware
- simplicity of no stuffing box
I've also considered an arrangement with some similar hardware for a
multihull where the motor would be mounted near the front crossbeam
and the prop shaft extends back to a strut near the rear crossbeam.
The prop could be lifted up out of the water when not in use. As
before, no stuffing box, no drag under sail, no growth, etc.
I have been looking for the answers to a couple of questions
regarding this arrangement:
1) Propeller efficiency vs. shaft angle. I believe this depends on
the type of propeller.
2) How to control whipping in the long unsupported shaft. The
textbook solution is to use a thicker shaft but that gets heavy.
The automotive solution to this is a hollow drive shaft. I have
never seen hollow shafts used on a boat. Are they available in
stainless steel?
I think the hardware to do stuff like this is non-standard. Does
anyone know US sources?
The 8.5 boat view from the top is almost exactly the same as Tennessee.
HJ
announcer97624 wrote:
HJ
announcer97624 wrote:
>
> I was searching the net for information on the longtail motors that
> are used in the Orient when I came across this interesting article.
> It has plans for four boats and information on an inboard liftable
> drive system that uses a small diesel engine for power. The boats it
> is designed for are very similar to Idaho, Tennessee, Dakota and
> Wyoming except they have a slight v-bottom.
>
>
I was searching the net for information on the longtail motors that
are used in the Orient when I came across this interesting article.
It has plans for four boats and information on an inboard liftable
drive system that uses a small diesel engine for power. The boats it
is designed for are very similar to Idaho, Tennessee, Dakota and
Wyoming except they have a slight v-bottom.
http://www.fao.org/DOCREP/003/W7260E/W7260E01.htm
A detailed description of how to make this unit is given in the
technical report: "Building a liftable propulsion system for small
craft - The BOB drive" published by the Bay of Bengal Programme and
obtainable from:
Fishing Technology Service
Fishery Industries Division
F.A.O.
Viale delle Terme di Caracalla
00100 Rome, Italy
I am sure many of you on the forum would be interested in a drive of
this type. It was designed to be less expensive than outboards and to
be used in shallow draft applications. The state that the drive is
very fuel efficient. I tried to find the plans on the internet but I
was unable. If anyone finds the plans please email me at
caj@...
Thank You,
John
are used in the Orient when I came across this interesting article.
It has plans for four boats and information on an inboard liftable
drive system that uses a small diesel engine for power. The boats it
is designed for are very similar to Idaho, Tennessee, Dakota and
Wyoming except they have a slight v-bottom.
http://www.fao.org/DOCREP/003/W7260E/W7260E01.htm
A detailed description of how to make this unit is given in the
technical report: "Building a liftable propulsion system for small
craft - The BOB drive" published by the Bay of Bengal Programme and
obtainable from:
Fishing Technology Service
Fishery Industries Division
F.A.O.
Viale delle Terme di Caracalla
00100 Rome, Italy
I am sure many of you on the forum would be interested in a drive of
this type. It was designed to be less expensive than outboards and to
be used in shallow draft applications. The state that the drive is
very fuel efficient. I tried to find the plans on the internet but I
was unable. If anyone finds the plans please email me at
caj@...
Thank You,
John