Hole in the garage?

[Terrible Buddhist]

Well it is still summer, which means winter is right around the corner in new england. unfortunately my trailer is sticking out of the garage in my new house. Is there a safe, cost effective way of removing the boat from the trailer for the winter?

[LS7]

I don't know what trailer you have but if it is tubular you can have someone cut it and rig you up with a detachable tougue setup.
LS

[Terrible Buddhist]

It is a competitive trailer...that is a really cool idea, I need to look into that.

[Jetmugg]

TB:
I have a Competitive trailer that was modified (by Competitive) to be a swing-away tongue. I can send some pics to you if you like. This modification reduced the overall length of my rig from over 23 feet to right at 21 feet 6 inches, from the folding part of the trailer, to the tip of the PD nozzle.
SteveM.

[Heatseeker]

I'd be interested to see the mods to your Competitive trailer. Mine won't fit in the garage due to the toungue also.
[This message has been edited by Heatseeker (edited August 15, 2001).]

[Havasu Hangin']

Here's how Extreme does it:
Extreme Trailer Options (http://www.extremetrailers.com/page6.html)
http://www.extremetrailers.com/6-17.jpg
http://www.extremetrailers.com/6-18.jpg
[This message has been edited by Havasu Hangin' (edited August 15, 2001).]

[058]

A friend had the same problem, He cut a small hole in his garage door for the tongue.

[jaqquuuz]

058 has the right idea if you can just cut a small hole in the garage door then build a box over the hole.

[gstark]

As a mechanical/structural engineer with a strong background in design and stress analysis, I can tell you that I personally would not choose a swing away tongue like the one shown. Particularily with heavy tongue weights, that connection which provides the function you want, can act as an elastic hinge. Repeated loading as encountered while trailering results in high bending loads at this hinge point that are reacted across the pins. The words "cumulative fatigue damage" come to mind, as do the words "eventual failure". Perhaps this has not happened (yet), but then again, this design is fairly new.
When I fabricated my removeable tongue, my choice was to telescope a 2.5" square tube inside 3.0" square tube. Cross pinned with a pair of grade 8 5/8 dia fasteners/pins. These pins are in pure shear and all bending loads are carried across the composite beam section. Just look at the typical draw bar that inserts into your receiver and you will understand what I am describing. Another benefit is that the tongue was removeable, so it was rather difficult to rip off the boat/trailer. Surge brake hydraulics coupled with a standard hydraulic quick disconnect fitting.

[RiverDave2]

GStark, I'm not an engineer of any sort, but (I know a thing or two about a thing or two) Cumulitive Fatigue is a characteristic of Aluminum Not Steel. The hinge pin as well as the locking pen where the lateral load would be placed are made of steel. With Steel if it holds, it holds throughout the test of time. (Providing no corrosion etc..)
RD

[Havasu Hangin']

Originally posted by gstark:
As a mechanical/structural engineer with a strong background in design and stress analysis...The words "cumulative fatigue damage" come to mind...
As a non-engineer, the words "duct tape" come to mind. http://www.goldenplasma.f2s.com/forum/smilies/happy09.gif
Originally posted by RiverDave2:
GStark, I'm not an engineer of any sort, but ...
Why is the prop on the back of the outdrive? http://www.goldenplasma.f2s.com/forum/smilies/confused27.gif
-Havasssssu Hangin'
http://www.websitemonster.com/images/pimp.gif

[gstark]

RiverDave2:
Cumulative fatigue is a stress analysis method (also known as Miners Law) based upon a known (or estimated) fatigue spectra with the intent of determining how close something is to failure. Every metal has what is known as an endurance limit, which is the stress level where infinite fatigue life exists. Therefore, cumulative fatigue damage can be applied to aluminum, carbon steels, alloy steels, titanium (comm. pure and alloy), nickel-based super alloys, etc. The technique has no dependency on the metal.
The hinge pin arrangement shown sets up a complex load and stress distribution in the attaching structure. That is what I am trying to get across. This arrangement also forms a weak link. Think of the trailer as a series of springs. The tab/pin arrangement acts as a spring. When trailering, high bending loads exist due to road accelerations (up/down motions). These bending loads are carried thru these "springs". Loads accumulate with time yielding fatigue. It may well be that the stress levels that result are below the endurance limit of plain carbon steel. If so, great. If not, sooner or later we'll see this in a courtroom as a product liability action.
Sorry, not on my trailer, carrying my boat with $$$ invested, attached to my tow rig ($$$) carrying my grandkids (priceless).

[jroos]

gstark, it sounds as if you are a metallurgical engineer. just curious.

[Jetmugg]

I am a metallurgical engineer. Steels have fatigue limits, aluminum alloys generally do not. This means that for steels, when cyclic stresses are applied at a level under this fatigue limit, failure will not occur. For aluminum alloys, cyclic stresses at any level will eventually cause fatigue failure (even though it may take millions of cycles).
On a practical level, I have had trailers with both removable (telescoping as described), and swing away. Both systems have worked well, although the telescoping is quicker to operate.
STeve.

[mister460]

I say convince the wife that you now HAVE to build a bigger garage/shop. It's the only way to be sure. If she says no, feed her the line about "cumulative fatigue" and those girls at Hooters need the money for college. Trust me, it'll work!

[jroos]

Tried that 460, now boat is in driveway and I`m in the garage!

[LS7]

lol

[gstark]

jroos:
I am a CA registered mechanical engineer, spent some time in met labs.
I work in aerospace and have been involved in the structural design of a whole bunch of really bitchen stuff that goes really fast and turns really hard. Jet boats, jets....
99% of my design background is Inconel and titanium based, so I am pretty weak in the subject of aluminum (Jetmug). All of my activity is fatigue-based by definition. It can be very surprising how fast fatigue cycles can add up, so while a million cycles may sound like a lot, that may represent several hours or several years of accumulation, depending on the load magnitude and frequency. That is why I am sensitive to a design such as the swing-away tongue. Fatigue design rules are one reason why most airplanes don't fall out of the sky, wings don't fail, horiz stabs stay intact, wing boxes carry their loads. For most of the stuff I am involved in, aluminum would fail in a heatbeat (temps greater than 800F).

[Jetmugg]

I love to see a good engineering discussion of just about anything. It's good to see a level of discussion above how many strippers will fit on any given jetboat, or how much beer someone can drink and still race his boat.
I have a particular interest in materials selection for all kinds of applications. There are available materials which would be better for jet drive manufacturing than those currently used. In particular, I would like to see someone make impellers from materials which are easier to cast, fabricate, and machine than the current crop of 300 series stainless steels. (I know of a few) Not only could we see an improvement in performance, but also lower cost.
Gstark is correct about the slip-in removable tongue being a more robust design. However, for some reason, the trailer manufacturers seem to have taken more of a liking to the swing-away design. Maybe they figure that we would lose the tongues if they were totally removable. LOL.
Steve.

[rivercrazy]

I have one of these slide in removable tongues with a quick brake line release. I've put tons of miles on the rig without any problems. For that reason I like the setup.
However, its a real pain in the rear to remove compared to the swingaway type. Also, when you disconnect the brake line, it always leaks a few drop of brake fluid. I believe it also introduces a very small amount of air in the brakes lines every time its disconnected. This requires bleeding the system from time to time.

[mister460]

Oh come on Jetmugg, how many strippers you can fit on a jetboat IS an engineering discussion. It deals with composite shear and tensile strength, as well as fatigue resistance and mass vs bouyancy issues! http://free.***boat.net/ubb/wink.gif Seriously though, do you know anything about the funtion and design of the adjustable jet nozzles on aircraft? I'm trying to work up a practical design for jetboats.

[Terrible Buddhist]

I am no engineer...but I will say the first design looked a lot more reliable over the long haul. I would love to see a picture of the slip in slip out method...not the strippers (althought those pictures would be nice too). What about taking the boat off the trailer for the winter?

[jaqquuuz]

After taking this enigineering class I have come to the conclusion ( cut a hole in the door):}

[gstark]

That is definitely the simplest and fastest solution to this problem.
Rivercrazy, you are right about a couple of drips. Keep in mind that hydraulic QDs are used on many aircraft hyd. systems, so they are a tried and true item. The swing away design may be more convenient, but.....
Terrible Buddhist, if I can figure out how to post photos, I can shoot a couple of digital pics of my former boat trailer.
Otherwise, I can e-mail you the pics at the address in your profile.
As far as taking the boat off the trailer, I live in So Cal, and the only time my boat was off its trailer, it was in the water.
Mister460, as far as adjustable nozzles on current jet engines, I am not aware of any. Thrust vectoring is used for a number of reasons, it is what keeps the Harrier afloat, the new Lockheed Skunk Works X-35 used vectored thrust from its turbine, combined with a lift fan in the center fuselage to lift vertically and hover. It then transitions to a flight regime using the vectoring nozzle. It recently went from hover to mach 1 plus in one flight. This was on the national news so I am not revealing any info that I should not.
Vectored thrust is analogous to use of a Place Diverter, as it is used to change the pitch of the hull. I will look in my publications for any info on adjustable nozzles.

[RiverDave]

There was some guys discussing an adjustable nozzle for jet boats, just like jet airplanes. It made significant performace increases in Hole shot as well as top speed. The first prototypes were made my Dana Marine but they never made it to Market becuase they felt it would be to expensive. Talk to Ultra 28 about it he knows alot more about it then I do.
RD

[Timer]

I'll throw my .02 cents into this as I'm also a licensed structural engineer.
I don't see a big problem with the setup pictured above if it's designed properly, although I feel more comfortable with the way mine was done.
Competitive Trailer installed my swing-away tongue. Two plates were welded to a hinge. The trailer tongue tube was cut and the face of each plate was welded to each cut surface of the tube. Four bolts, one at each corner, close the plates face-to-face to give a tight friction connection. The bottom 2 bolts take the majority of the load in tension, as long as all the bolts are adequately tightened.

[Timer]

OK, OK, so it should be "2 cents"

[jimmmyb]

T-B
my 2 sense worth.
i don't know s--t about metal,
but i would choose 1 of the two methods talked about. DO NOT CUT A HOLE IN YOUR GARAGE DOOR,this looks about as good as tire rims on front lawn as planter box's.
my point being if you have a decent pad,
hole in garage door = tacky,
not to mention that dam mailman trying to fill your boat up with ed mcman junk mail.

[wsuwrhr]

You can see how i lifted my boat off the trailer and placed it on a roller cart I made. My wife didn't liek the idea so I sent her to the store before I rigged it up, works every time. www.briansboatshop.com (http://www.briansboatshop.com)

[wsuwrhr]

You can see how i lifted my boat off the trailer and placed it on a roller cart I made. My wife didn't like the idea so I sent her to the store before I rigged it up, works every time. www.briansboatshop.com (http://www.briansboatshop.com)

[Terrible Buddhist]

I have to agree...a hole in the garage is...ummm, less than the image I would like to portray. That lifting rig looks real interesting...can you send me a larger picture?