Another axle placement question (sorry)

[BillZ]

I pm'ed this question to one of the resident experts but thought it would be worth asking on the forum because it might help someone else.

The axle on the trailer I have for my 5x8 build is too near the center (43 1/2" from rear to center of wheel) and I plan to have a welder move it back. I have read discussions here about axle placement and that it should be 35%-40% from the rear. My main question is; Does the length from the tongue to the front of the frame affect your axle placement?

My length from center of the receiver (where the ball goes) to the front of the trailer floor is about 39". I see that other trailers have a somewhat longer span of length, say, 48". Do I need to take that into account when I calculate my axle placement?

I need to be fairly careful about weight distribution because the recommended max tongue weight for my Subaru Forester is only 200 lbs.

[parnold]

Bill:

I saw in antother thread where someone suggested using jackstands, and experimenting with locations on the frame to get the tongue weight you want. It would be a little tedious, but certainly would be an accurate way to do it.

[BillZ]

Bill:

I saw in antother thread where someone suggested using jackstands, and experimenting with locations on the frame to get the tongue weight you want. It would be a little tedious, but certainly would be an accurate way to do it.

I can do that before I build the camper?

[teardrop_focus]

I can do that before I build the camper?

Why not? If you have a good idea of what it is you'll be taking with you... things like your 12V systems' battery... cast iron cookware... stoves, fuel, etc... lay it all out of a sheet of ply. You don't even need jackstands... you can use 1.5" or 2" closet dowel, for example, to serve as a fulcrum to determine a rough balance.





Have you read Andrew/angib's formula for axle placement?

angib's --->Trailer Balance<--- spreadsheet



He also gives the "simple" answer:

Are all those numbers above just unnecessarily complicated? You just want an answer, not to have to take an exam?
Here are some really simple 'rules of thumb' that you can apply:

40% (eg, 38" from back for 8ft body) - A reasonable compromise value for an average teardrop.

45% (eg, 43" from back for 8ft body) - Tongue box. Light or no galley. Minimum safe hitch weight wanted.

35% (eg, 34" from back for 8ft body) - Well-equipped/heavy galley. Long tongue. Heavier hitch weight wanted.

[BillZ]

I can do that before I build the camper?

Why not? If you have a good idea of what it is you'll be taking with you... things like your 12V systems' battery... cast iron cookware... stoves, fuel, etc... lay it all out of a sheet of ply. You don't even need jackstands... you can use 1.5" or 2" closet dowel, for example, to serve as a fulcrum to determine a rough balance.





Have you read Andrew/angib's formula for axle placement?

angib's --->Trailer Balance<--- spreadsheet



He also gives the "simple" answer:

Are all those numbers above just unnecessarily complicated? You just want an answer, not to have to take an exam?
Here are some really simple 'rules of thumb' that you can apply:

40% (eg, 38" from back for 8ft body) - A reasonable compromise value for an average teardrop.

45% (eg, 43" from back for 8ft body) - Tongue box. Light or no galley. Minimum safe hitch weight wanted.

35% (eg, 34" from back for 8ft body) - Well-equipped/heavy galley. Long tongue. Heavier hitch weight wanted.

I have seen Andrew's formula, thanks. I can be pretty safe in saying that the 40% average distance will likely apply-that is, depending on the answer to my question about tongue length.


Just got an answer to my pm to Andrew. I don't think he will mind me posting here, Thanks Andrew!



Bill,

The length of the tongue or A-frame doesn't make much difference - for example it can only alter the tongue weight by 1-2% unless it is made outrageously long or short.

So it's where the axle is relative to the length of the trailer body that matters. 35-40% of the body length from the back of the body is about right. Your frame is probably the same length as the body, but in case you are planning to overhang the front or back, it is the measurments from the back of the body that matter, not fropm the back of the frame if that is different.

The reason that the tongue length doesn't make much difference is because it's the distance from the coupler to the axle (ie, tongue plus around half the body length) that affects the balance and so changing just the tongue only alters this a bit.

Andrew

[bobhenry]

I went 65 % / 35% of the body length and still have problems at interstate speed. I am going to lengthen the tongue 18' ( EVEN THOUGH IT IS NOT SUPPOSED TO HELP)

[eamarquardt]

This question has been beaten to death a thousand times.

IMHO there is NO WAY to accurately determine where your axle should be placed till your teardrop is finished and loaded as it will be when you are ready to hit the road. Any attempt to say exaclty where the axle should be places is a SWAG!

http://www.urbandictionary.com/define.p ... g+(s.w.a.g.)

See #2

Many get LUCKY with their SWAG!

Better (IMHO) is to plan ahead and make the axle moveable. I welded the spring hangers to a piece of angle iron which can be mounted anywhere along the frame.



I'm currently in the planning phase for a trailer to haul a baja bug and two motorcycles for my son. I plan on making it out of 1/8X2X2 angle iron. I'm concerned about welding the spring hangers to the 1/8 and want to spread the load a bit so I'm planning on welding the spring hanges to 2X6Xmaybe 3/8 and bolting these pieces to the 1/8 angle iron. Can put the axle anywhere and remove the spring hangers easily if they get worn.

My thinking is "outside the box" for many but implementing my thoughts doesn't cost much and gives me flexibility to change things later should I want to.

There you have it again, the world according to Gus. You, of course, are free to disagree.

Cheers,

Gus

[teardrop_focus]

eamarquardt

IMHO there is NO WAY to accurately determine where your axle should be placed till your teardrop is finished and loaded as it will be when you are ready to hit the road. Any attempt to say exaclty where the axle should be places is a SWAG!

Relax.

Sure, it's nice to have a sliding axle... but you CAN ballpark axle placement (people have done this before! They've built teardrop trailers and loaded them!) to a close margin.

What's left after that if someone actually goes to the trouble of measuring their tongue weight (you can bet I certainly will, and, often!) is a usually straightforward matter of distributing some of the cargo weight for traveling with the desired tongue weight.

Andrew/angib has gone to considerable lengths for this forum, free of charge I might remind you, to help people like Bill and myself get their simple trailers built and I don't think it's fair to him to make statements of the kind which I have just quoted.

You're a bright and personable person in real life, sir, but, again, your delivery here in posted form can sometimes leave something to be desired.

Bill asked a question... and we can only answer as best we can, and, attempt not to disrespect the few here who've made considerable contributions to this great little message board forum website.

[eamarquardt]

Relax.

Sorry you felt my reply was brusk. 8.5/10 on pain scale today. Not a happy camper to say the least. Chronic, severe, intractable, untreatable pain SUCKS. No sugar coating it!

One of the posts in the string followed the most extreme example (35%/65%) of the "simple answer". It's not working. What more can I say. I agree there was a lot of work put into the spreadsheet but the end result still fits the defination of a SWAG to the T. It is a reasoned guess.

You are absolutely right. A lot of people get lucky or compromise by rearragning the packing of their trailer to get the balance they missed on the first go around.

By making the springs moveable (either on a couple of pads to bolt on or one piece like I've done in my picture) you can get it right the first time, every time. No guesswork. Yeah, it's not done by many but it works flawlessly.

The originator of the string kinda appolgized in his first post for asking the question again. I merely echoed that in my post.

My posts are not offered as criticism. Merely a different approach to the same issue. It doesn't concern me if someone doesn't agree. What bothers me that some percieve a thought different to their own as criticism of their thoughts. Not so in my mind. Only one person knows to what extent anyone is willing to "compromise" and everything in life is a compromise.

You've said to me: "Some people just don't get it". Your way of saying to me different thoughts are ok! That's how I see it also.

So, there you have it again, the "world according to Gus". You, of course, are free to disagree.

Cheers,

Gus

[teardrop_focus]

8.5/10 on pain scale today. Not a happy camper to say the least. Chronic, severe, intractable, untreatable pain SUCKS.

Ah. I had overlooked that as an influence. Forgive me. And that would be, "sucks donkey balls". My bad.



Carry on.

[angib]

Yep, there's the simple rule of thumb or educated guess.....

and then there's the detailed part-by-part weight estimate that gives an accurate prediction.

What isn't possible is a highly accurate simple method. That would come under the heading of free lunches and similar....

Andrew

[eamarquardt]

and then there's the detailed part-by-part weight estimate that gives an accurate prediction.
Andrew

I agree that if you put enough effort into it, you can predict the future. Most don't and some experience problems. You can get it right the first time by mounting the springs/axles last. I believe that it is better not to admire your beautiful paint job from the corner you've just painted yourself into.

There you have it, again. The world according to Gus. You, of course, are free to disagree.

Cheers,

Gus