My Giant Teardrop build

Design & Construction of anything that's not a teardrop e.g. Grasshoppers or Sunspots

Postby Ivar the Red » Fri May 09, 2008 5:21 am

Thanks for the input. After the plan started to come together, I was feeling a little concerned about tongue weight, and as Kerry said ther will be a rather large storage area in front. This plus the decking, any tongue box for batteries, being as light as possible in the galley, or the possible A/C hopefully will make it allright. If tongue weight does rear it's ugly head though, the axles are moveable.
Image
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)

Postby toypusher » Fri May 09, 2008 5:33 am

Another suggestion for you Johnny. If you are going to have onboard water, then put it forward as well as a greywater tank if you are going to have one.
User avatar
toypusher
Site Admin
 
Posts: 43040
Images: 324
Joined: Fri Jan 28, 2005 12:21 pm
Location: York, PA Area

Postby Ivar the Red » Fri May 09, 2008 5:42 am

Mary K wrote:But who does the Pink Flamingo belong too???:thinking: :lol:



You got all that trailer, you should consider a standy. Getting dressed standing up is so much easier. Trust me.
Is that the correct location? With the wheels and all??

Regardless, I do like the profile. :thumbsup:


Mk


Thanks MK,
All good questions indeed. I did think 'bout a standy, but I think it's personal preferances that took over, this profile is more "teardropy", the whole weight issue, and I don't want to be so big as to not be welcome at the gatherings.imho. :lol:

As to the getting dressed thang, I seen Smokeybob's idea a while back(with the curtain room on the side) and I really like that idea.

That should be the final location, gotta think about some fenders.And there are big flocks of Pink Flamingos at Wally world. :thumbsup:
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)
Top

Postby PaulC » Fri May 09, 2008 5:46 am

Whoa!!!!!!!!!!!!!!!!!!!!!!!!!!!!Slow down everybody. The general rule of thumb is 10% of Total bodyweight as the ideal tongue weight. I predict this will make his ideal tongue weight around the 400 pounds plus, if he continues along these lines. If Ivar is serious about building this, the Mother of all Td's, his main aim is to balance his build around that centre tandem axle. Then he can adjust his frontal loading and build to give a nominal tongue weight that his tow vehicle can handle.
Andrew can probably confirm, or destroy this, but I think you'll find that you are all barking in wrong direction.

Cheers
Paul :thumbsup:
PS slightly different rules apply when you start using tandem axle trailers.
Time is the only real capital we have. Money you can replace but time you cannot.
User avatar
PaulC
3rd Teardrop Club
 
Posts: 4439
Images: 36
Joined: Mon May 24, 2004 7:27 am
Location: Laura, SouthernFlinders Ranges, South Australia
Top

Postby Ivar the Red » Fri May 09, 2008 5:54 am

PaulC wrote:Whoa!!!!!!!!!!!!!!!!!!!!!!!!!!!!Slow down everybody. The general rule of thumb is 10% of Total bodyweight as the ideal tongue weight. I predict this will make his ideal tongue weight around the 400 pounds plus, if he continues along these lines. If Ivar is serious about building this, the Mother of all Td's, his main aim is to balance his build around that centre tandem axle. Then he can adjust his frontal loading and build to give a nominal tongue weight that his tow vehicle can handle.
Andrew can probably confirm, or destroy this, but I think you'll find that you are all barking in wrong direction.

Cheers
Paul :thumbsup:
PS slightly different rules apply when you start using tandem axle trailers.

Thanks Paul, I was hoping you would chime in, maybe I'll pm Andrew and see if he'll add his $.02.
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)
Top

Postby starleen2 » Fri May 09, 2008 8:11 am

PaulC wrote: If Ivar is serious about building this, the Mother of all Td's. . .


I thinks you have your TD's Name ... MOATDs
User avatar
starleen2
5th Teardrop Club
 
Posts: 16272
Images: 224
Joined: Sat May 12, 2007 8:26 pm
Location: Pea Ridge ,AR
Top

Postby angib » Fri May 09, 2008 3:54 pm

It seems to me the first thing to do is to haul that trailer down a weighbridge and find out what it weighs, as it is now - it looks heavy, but then there's quite a few bits, like the cross-members, that are just flanged sheet and could be quite light.

If they'll let you, weighing it complete standing on its prop stand and then weighing just the axles with the prop stand off the weighbridge would be useful as that would tell you what the hitch weight is now.

At first sight the weight layout of what you're adding doesn't look too good - the weight of the body is centred maybe a little behind the last axle - however if you are looking to carry much on that deck, the deck itself is going to weigh quite a lot. It would be easy to make the deck both indestructible and heavy, which would kill two birds with one stone.

If I just assume the deck weighs the same per foot of length as the body behind it, the centre of the weight you're adding falls somewhere around 10% forward of the equalisers (between the axles) which is about as near perfect as you could want.

If you want to carry much on the deck, you should note that about 60% of the cargo weight will end up on the hitch and only about 40% on the trailer's axles. But it looks like a Durango can carry so much weight on its hitch that you'd be hard pressed to get anything heavy enough onto the deck to overload the hitch.

So it looks good, but finding out the trailer weight before you start could avoid tears later.....

Andrew
User avatar
angib
5000 Club
5000 Club
 
Posts: 5783
Images: 231
Joined: Fri Apr 30, 2004 2:04 pm
Location: (Olde) England
Top

Postby Ivar the Red » Fri May 09, 2008 5:26 pm

Thank you very much Andrew. I'll make that my weekend challenge; to find a scale. I hope I don't have to pull it all the way to Lawton, it's quite bouncy as it sits now.

I think there is some miss-conception about the deck on front. This is not a toy hauler like those Lil Guy 6 Wides.(for one thing, I have no toys) It is just a deck, like to sit on and watch the sunset and maybe have a cold one(or 6). If the extra weight is needed up front, I think I could come up with railings, or bench seats, or whatnot.

Now, out back. I'm not planning any kind of luxury galley or something like that, it will be bare-bones. The main cabin will be double walled, with the bead board on the outside, foam board insulation, then polly some kind of paneling. Once I get to the galley I think I could go with just the single wall.

Anyways, now my brain hurts, and I want to go home. Thanks everyone soooo much for the input thus far, it is really helpful.

:thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :thinking: :lol: :lol: :lol: 8)
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)
Top

Postby brian_bp » Fri May 09, 2008 6:00 pm

I agree that front/rear distribution is a problem, because the amount of stuff in the front is so variable. The Trailer Balance Worksheet is definitely called for here.

For this situation of forward-located cargo (in the compartment, I realize there's none on the deck), one approach is to balance for just adequate tongue weight without cargo, and know that with cargo it will only go higher. Then work out the worst case of full cargo, and ensure that the tug is adequate.

Even when the front/rear balance is settled, and tongue weight seems okay, this will be a poor configuration for stability, because the masses are at the ends (the middle has just a bed and lots of air space). This is the "high polar moment of inertia" situation which has been discussed before - the trailer acts like a flywheel, so once it starts rotating (yawing or swaying in direction), it wants to keep going.

I think the traditional rear-heavy teardrop layout is great for stability if the axle is well placed, but does not lend itself well to a forward cargo load.

With the deck weighing very little, it does look like the axles need to move back, at a guess.

It might be cool if the front corners of the deck folded over, so the deck could run very close to the tug in use, but fold out of the way for towing to allow good turning angles.
brian_bp
1000 Club
1000 Club
 
Posts: 1355
Images: 9
Joined: Sun Nov 19, 2006 1:25 pm
Location: Alberta
Top

Postby brian_bp » Fri May 09, 2008 6:13 pm

angib wrote:It seems to me the first thing to do is to haul that trailer down a weighbridge and find out what it weighs, as it is now - it looks heavy, but then there's quite a few bits, like the cross-members, that are just flanged sheet and could be quite light.

If they'll let you, weighing it complete standing on its prop stand and then weighing just the axles with the prop stand off the weighbridge would be useful as that would tell you what the hitch weight is now...

I vote for getting some real weight data, too.

The "prop stand" (a.k.a. tongue jack) is mounted well back from the coupler, so it will carry more load than the hitch will. It's relatively easy to calculate a correction if you use that jack rather than a stand under the coupler, if the coupler-to-axle (middle of the two) and coupler-to-jack distances are known. Distances (from coupler to axles at least) are needed for the balance worksheet anyway; the layout from back on Tuesday had dimensions, and if the earlier tape measure shot was from the rear of the trailer, I guess we have the tongue length as well, so we only need the jack position.

The height of the tongue always matters when weighing, but especially with tandem axles. If it is too high, for instance, the tongue jack will be lifting load off the front axle and transferring it to itself and the rear axle. The trailer should be set up level, so the axle load is equalized, both for towing and for this measurement.
brian_bp
1000 Club
1000 Club
 
Posts: 1355
Images: 9
Joined: Sun Nov 19, 2006 1:25 pm
Location: Alberta
Top

Postby toypusher » Fri May 09, 2008 6:16 pm

brian_bp wrote:..........It might be cool if the front corners of the deck folded over, so the deck could run very close to the tug in use, but fold out of the way for towing to allow good turning angles.


That is a cool idea. Allows for a much bigger deck and you could build in some foldup steps too. All that would also help add some more weight up front.

I still don't understand why everone seems to think that the galley weight will be a problem. When camping, it will have stuff in it, but so will the front storage area. When not camping, it should not have any more weight than the sleeping area does. JMO

Edit: Just wanted to add that my galley is only heavy due to the fact that there is a 7gal water tank directly under it. When the tank is empty, the galley is very light indeed compared to the rest of the tear. Cabinetry in the galley is not much more than the interior and the upper cabinets are over the axle location, whereas the interior cabinets are forward of the axle placement. And I have a tongue box.
User avatar
toypusher
Site Admin
 
Posts: 43040
Images: 324
Joined: Fri Jan 28, 2005 12:21 pm
Location: York, PA Area
Top

Postby Ivar the Red » Fri May 09, 2008 10:21 pm

:? :? :?
oh wow man. Well, been looking, and I guess I'll be making a bouncy trip to Lawton tomorrow. No scales here. Booo.
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)
Top

Postby Ivar the Red » Fri May 09, 2008 10:31 pm

brian_bp wrote:
It might be cool if the front corners of the deck folded over, so the deck could run very close to the tug in use, but fold out of the way for towing to allow good turning angles.


Please expand on this idea. :thinking: :worship:
Johnny
BUILD THREAD
Winning is not a sometime thing; it's an all time thing. You don't win once in a while, you don't do things right once in a while, you do them right all the time. Winning is habit. Unfortunately, so is losing. - Vince Lombardi
ImageImageImage
User avatar
Ivar the Red
HOME RUN TILT
 
Posts: 19376
Images: 373
Joined: Thu Aug 16, 2007 2:32 pm
Location: Duncan,OK(The dark side of the moon)
Top

Postby brian_bp » Sat May 10, 2008 2:55 pm

toypusher wrote:...I still don't understand why everone seems to think that the galley weight will be a problem. When camping, it will have stuff in it, but so will the front storage area. When not camping, it should not have any more weight than the sleeping area does. JMO

When not camping, with everything not built-in removed from the trailer, I can see the galley being not much heavier than a bed area... but does it matter?

When camping, the galley would normally have a stove (maybe with fuel), sink, cooler or refrigerator, all of the food, pot & pans (including cast iron for many T&TTT members), dishes & cutlery... almost everything carried in the trailer other than clothing.

The front storage area is the big unknown... will it carry some light and bulky stuff (not enough to balance the galley) or a ton of equipment?

A while ago there was a commercially-made stand-up trailer with outside rear galley discussed here, and I commented that in the specs it had an unreasonably high tongue weight. The designer responded that by the time the galley is loaded, the balance would be right... because the galley area gets so heavy.

In some individual cases, the galley might not be such a concentrated load.
brian_bp
1000 Club
1000 Club
 
Posts: 1355
Images: 9
Joined: Sun Nov 19, 2006 1:25 pm
Location: Alberta
Top

Postby brian_bp » Sat May 10, 2008 3:00 pm

Ivar the Red wrote:
brian_bp wrote:
It might be cool if the front corners of the deck folded over, so the deck could run very close to the tug in use, but fold out of the way for towing to allow good turning angles.


Please expand on this idea. :thinking: :worship:

Sure... give me a day to get a chance to draw something. Others can chip in with their ideas on this theme, if they follow what I'm getting at.
brian_bp
1000 Club
1000 Club
 
Posts: 1355
Images: 9
Joined: Sun Nov 19, 2006 1:25 pm
Location: Alberta
Top

PreviousNext

Return to Non-traditional Designs

Who is online

Users browsing this forum: No registered users and 1 guest