Calculating Frame height -> Counter height

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Calculating Frame height -> Counter height

Postby switterstx » Sun Dec 02, 2007 1:13 pm

So I have my frame all figured out in my head but what I'm having trouble on at the drawing board is how to estimate height? Specifically I'm looking to have the counter at the standard 36" off of the ground and to do that I need to be sure the frame is at a certain point within a few inches off the ground.

Also I'm wanting it to tow nearly level behind my vehicle. I can get the height from ground to my hitch but how do I translate that back for the wheels. I'm planning on some sort of torsion axle (probably a single as opposed to split) as I'm sure a sprung axle, even underslung (or overslung?) will add too much height.

I'm sure it is related to the size of the wheels, that makes sense but what about tire sidewall, etc.?

As always, all help appreciated.
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Postby madjack » Sun Dec 02, 2007 2:28 pm

...here is a tire size calculator http://www.miata.net/garage/tirecalc.html ...for example, if you had a 26" tall tire on a torsion axle with a 0* start angle, you would have 13"s to the centerline, giving around 14"s to the bottom of the frame...if you have a receiver type hitch you needn't worry about height since you can make adjustments for that with differing sizes of drawbars.........
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Postby asianflava » Sun Dec 02, 2007 5:41 pm

I wouldn't get overly concerned about the height. Just try to get it in the ballpark. My counter height at Inks Lake was probably a foot lower than than it was at Lake Bistineau.

The pad at Inks was uphill, I think my tongue jack was extended about as far as it would go to keep the cabin level. The pad at LCG was downhill, even with the tongue jack at it's lowest setting, I still had to but 2in leveling blocks under the tires.
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Postby mikeschn » Sun Dec 02, 2007 6:21 pm

Several factors come into play.

The wheel diameter
the start angle of the axle
the camping weight of the trailer

I did up a tiny spreadsheet that lets you calculate the distance from the ground to the chassis. You can get that here

http://www.mikenchell.com/images/wheelcentercalc.xls

It's not perfect, but it'll get you in the ballpark!

Mike...

P.S. Just for fun, change the wheel OD to 26" and the angle to 22 degrees. Then all the numbers on the spreadsheet match up with the picture in the spreadsheet.
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Postby bobhenry » Mon Dec 03, 2007 9:12 am

That is a good example of advanced planning but can't this wait until the frame is built. My HF trailer was 18" to the frame. After adding for the floor it was 19" +/- so I built my cabinet bases 15" tall. If you add the top thickness the final height with the trailer dead level was 35". Wife is 5'4" so they are a little shy. If you are both tall add an 1" or so. A mock toe kick , short cabinets or shallow drawers could be added to the bottom after the fact if you find them a bit short. This could provide a great place for griddles or skillets. Remember space is at a premium so design all of the little cubby holes with a use.
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Postby Benthosboy » Wed Dec 05, 2007 1:46 pm

Translation please :? , counter= ?

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Postby depatty » Wed Dec 05, 2007 1:53 pm

Benthosboy wrote:Translation please :? , counter= ?

Martyn. (apologies for hijack :oops: )


The table top or cooking top height of the cooking area in the rear of the teardrop.

HTH
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Postby Benthosboy » Wed Dec 05, 2007 2:20 pm

depatty wrote:
Benthosboy wrote:Translation please :? , counter= ?

Martyn. (apologies for hijack :oops: )


The table top or cooking top height of the cooking area in the rear of the teardrop.

HTH
Dave


Much thanks.

Martyn.
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