Critique my trailer plans

Ask questions about Harbor Freight trailers, or questions about building your own...

Critique my trailer plans

Postby boulderv7 » Mon Jun 07, 2021 1:46 pm

I am basing my design off of Tony's trailer plans in his book, except we are only going 9' long instead of 10'. So I did center the axle at 40" from the rear instead of 44' like he did. I am also planning on having body mount tabs for the body and tongue box. Our teardrop will be 48" tall, Benroy style.

I am going to have the frame .5" narrower and 1'' shorter than the body to allow for some overhang and wiggle room with mounting.
Planning on a #9 Dexter Torsion axle downrated to 1600lbs, start angle 22.5" down, with 5 on 4-1/2" studs bolt pattern, with electric brakes
2" square steel tubing, 1/8" thick walls for the frame and cross members, except for the galley crossmember, which will be 2" angle.

Let me know what you think. Pretty much copied Tony's plans except the length and added the tongue mount tabs...maybe those are not needed? My other questions are about the axle...since this is not my area of expertise...I assume this setup will be adequate, given my trailer will be shorter, and most likely lighter, but will this axle be too much? Should I choose a different axle setup?

Thanks for your input.

165901
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am

Re: Critique my trailer plans

Postby Tom&Shelly » Mon Jun 07, 2021 2:32 pm

boulderv7 wrote:I am basing my design off of Tony's trailer plans in his book, except we are only going 9' long instead of 10'.

Let me know what you think.


Why only 9'? Whenever I modify dimensions in a design, I seem to mess something up somewhere along the line. Not a big deal--just wastes some material and time. (And usually I can re-use the material somewhere else, eventually.) But that's just me. I'd need a pretty compelling reason to cut off a foot.

Tom
174145 170466 173366
Tom&Shelly
Palladium Donating Member
 
Posts: 2349
Images: 2170
Joined: Tue Sep 05, 2017 3:27 pm
Location: New Mexico

Re: Critique my trailer plans

Postby boulderv7 » Mon Jun 07, 2021 3:17 pm

Tom&Shelly wrote:
boulderv7 wrote:I am basing my design off of Tony's trailer plans in his book, except we are only going 9' long instead of 10'.

Let me know what you think.


Why only 9'? Whenever I modify dimensions in a design, I seem to mess something up somewhere along the line. Not a big deal--just wastes some material and time. (And usually I can re-use the material somewhere else, eventually.) But that's just me. I'd need a pretty compelling reason to cut off a foot.

Tom
Mostly weight, cost and need. After I figured out everything we needed/wanted, it all fits in a 9' profile, so I figure why the extra foot? We basically decided we don't need/want the headboard in Tony's design, so that essentially dropped a foot from the profile. Hence the 9'. Are we gonna miss the extra foot? Maybe....will that mean I need to build another teardrop? Maybe....lol. That's ok with me.

Sent from my moto z3 using Tapatalk
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am
Top

Re: Critique my trailer plans

Postby saltydawg » Mon Jun 07, 2021 4:01 pm

Well I would shift to 2x3 .085 wall rect tube and save some weight and be a little stronger over all. It saves about .3 lb for every foot of tube, which adds up when you figure all the lengths needed.
Scott
Lost in Maryland
2021 just said to 2020, hold my beer and watch this.
saltydawg
500 Club
 
Posts: 647
Joined: Tue Apr 24, 2012 8:34 pm
Location: Maryland
Top

Re: Critique my trailer plans

Postby boulderv7 » Mon Jun 07, 2021 6:31 pm

saltydawg wrote:Well I would shift to 2x3 .085 wall rect tube and save some weight and be a little stronger over all. It saves about .3 lb for every foot of tube, which adds up when you figure all the lengths needed.
This is a good suggestion. I assume the 3" dimension would oriented vertically, correct?

Sent from my moto z3 using Tapatalk
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am
Top

Re: Critique my trailer plans

Postby saltydawg » Mon Jun 07, 2021 7:16 pm

boulderv7 wrote:This is a good suggestion. I assume the 3" dimension would oriented vertically, correct?

Sent from my moto z3 using Tapatalk


Yes, below is some deflection calcs. the important thing is the internal psi numbers, the flex does matter but the internal stress gives you how close to failure the steel is. Remember most mild steel is around 30-40 thousand psi strength. I included just for giggle 1x3 085, it flexes less than 2x2 120 but is a little higher stress.

Image
Image
Image
Scott
Lost in Maryland
2021 just said to 2020, hold my beer and watch this.
saltydawg
500 Club
 
Posts: 647
Joined: Tue Apr 24, 2012 8:34 pm
Location: Maryland
Top

Re: Critique my trailer plans

Postby tony.latham » Tue Jun 08, 2021 7:34 am

Well I would shift to 2x3 .085 wall rect tube and save some weight...


It is a good suggestion. Just keep in mind that .083 is more challenging to weld than .120" --that's why I avoided it in the book. The other thing is that square tubing for the tongue works well for the removable coupler. But you could certainly stick with my tongue and the thinner rectangular steel for the frame.

Image

Tony
User avatar
tony.latham
Gold Donating Member
 
Posts: 7011
Images: 17
Joined: Mon Jul 08, 2013 4:03 pm
Location: Middle of Idaho on the edge of nowhere
Top

Re: Critique my trailer plans

Postby swoody126 » Tue Jun 08, 2021 8:12 am

most materials come in 2' increments w/ metal coming in either 20' or 22' lengths neither of which divides by 9 evenly

so ... IMHO making a frame members roughly dividable by 2'± wastes very little/much less

plywood comes in 8' lengths x 4' widths

w/ frame members set on 24"± centers one can maximize the use of plywood

when targeting the 24" marks w/ a slight bit of fudge factor for mounting convenience you waste less material

stretching your 9' idea to 10' will consume virtually the same amount of labor ... like within 15 minutes± either way/operation/day's labor

just something i try to wrap my mind around when designing/selecting a project and i still end up adding to my collection of pieces of materials for tiny projects

Tony's headboard might could be quite handy ... specially if it didn't consume any extra materials

just this old cheapsteak's 2¢ worth this morning

BON CHANCE

sw
"we are the people our parents warned us about" jb
swoody126
500 Club
 
Posts: 769
Joined: Mon Feb 22, 2016 6:11 pm
Location: north of Ft Worth
Top

Re: Critique my trailer plans

Postby boulderv7 » Tue Jun 08, 2021 4:28 pm

Yeah I'm gonna have a friend who welds by trade weld it up for me. I'll ask him about working with the thinner material. My experience with welding was limited to high school shop. ;)

Sent from my moto z3 using Tapatalk
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am
Top

Re: Critique my trailer plans

Postby boulderv7 » Tue Jun 08, 2021 4:34 pm

tony.latham wrote:
Well I would shift to 2x3 .085 wall rect tube and save some weight...


It is a good suggestion. Just keep in mind that .083 is more challenging to weld than .120" --that's why I avoided it in the book. The other thing is that square tubing for the tongue works well for the removable coupler. But you could certainly stick with my tongue and the thinner rectangular steel for the frame.

Image

Tony
swoody126 wrote:most materials come in 2' increments w/ metal coming in either 20' or 22' lengths neither of which divides by 9 evenly

so ... IMHO making a frame members roughly dividable by 2'± wastes very little/much less

plywood comes in 8' lengths x 4' widths

w/ frame members set on 24"± centers one can maximize the use of plywood

when targeting the 24" marks w/ a slight bit of fudge factor for mounting convenience you waste less material

stretching your 9' idea to 10' will consume virtually the same amount of labor ... like within 15 minutes± either way/operation/day's labor

just something i try to wrap my mind around when designing/selecting a project and i still end up adding to my collection of pieces of materials for tiny projects

Tony's headboard might could be quite handy ... specially if it didn't consume any extra materials

just this old cheapsteak's 2¢ worth this morning

BON CHANCE

sw
Very good points all around. And something I have thought about. I'm still trying to keep the weight down though too, and would ideally like to be able to tow it easily with a vehicle with a 1500lbs tow rating. My wife wants to upgrade her sedan to a crossover type, but I currently have a Honda pilot with a 3500lb rating, so going a bit heavier wouldn't exactly be a deal breaker. I *think* 9' would be in that sweet spot for us, just big enough and just light enough...

But thats why I'm here, to ask questions and get feedback from people with experience.

Sent from my moto z3 using Tapatalk
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am
Top

Re: Critique my trailer plans

Postby tony.latham » Tue Jun 08, 2021 4:58 pm

I *think* 9' would be in that sweet spot for us...


If I told my wife I was going to build a teardrop without a headboard, I'd be discussing the issue with a marriage counselor. Probably by myself.

:frightened:

They are that handy.

Tony
User avatar
tony.latham
Gold Donating Member
 
Posts: 7011
Images: 17
Joined: Mon Jul 08, 2013 4:03 pm
Location: Middle of Idaho on the edge of nowhere
Top

Re: Critique my trailer plans

Postby saltydawg » Tue Jun 08, 2021 5:51 pm

boulderv7 wrote: I'm still trying to keep the weight down though too, and would ideally like to be able to tow it easily with a vehicle with a 1500lbs tow rating. My wife wants to upgrade her sedan to a crossover type...

But thats why I'm here, to ask questions and get feedback from people with experience.

Sent from my moto z3 using Tapatalk


if you want to save more weight make your cross members except the front one from 1x3 085, it weighs 2.1 lbs per foot. also make you tongue angles from it too. So a savings of almost a lb per foot over 2x2 120, and has less flex, and another 1/2 lb saved over 2x3 085. I built a frame like this, the total weight sans axle was under 150. It is plenty strong for a 1000 to 1300 lb trailer, if you get over 1300 I would not reduce the tongue angles to the 1x3.
Image
Image

edit before someone asks, I smear seam sealer over all my welds before I paint to help stop rust getting in any pin holes in the welds.
Scott
Lost in Maryland
2021 just said to 2020, hold my beer and watch this.
saltydawg
500 Club
 
Posts: 647
Joined: Tue Apr 24, 2012 8:34 pm
Location: Maryland
Top

Re: Critique my trailer plans

Postby boulderv7 » Tue Jun 08, 2021 6:09 pm

Now you guys got me thinking 10' is the way to go...and my wife is now like "the headboard would be nice"...

Thanks guys!



Sent from my moto z3 using Tapatalk
boulderv7
Teardrop Inspector
 
Posts: 15
Images: 1
Joined: Fri May 28, 2021 12:50 am
Top

Re: Critique my trailer plans

Postby tony.latham » Tue Jun 08, 2021 7:05 pm

Thanks guys!


:thumbsup:

Tony
User avatar
tony.latham
Gold Donating Member
 
Posts: 7011
Images: 17
Joined: Mon Jul 08, 2013 4:03 pm
Location: Middle of Idaho on the edge of nowhere
Top

Re: Critique my trailer plans

Postby QueticoBill » Wed Jun 09, 2021 5:12 am

Interesting discussion. My plan is around 9'+ based on the roof being 10' and hatch 5' - three 5' x 5' pieces of baltic birch. I like eliminating a seam.

We all have different priorities and things we'd like to avoid.
QB
A tear with no name: viewtopic.php?f=50&t=67624
QueticoBill
Silver Donating Member
 
Posts: 1197
Images: 22
Joined: Sun Apr 14, 2013 7:22 am
Location: Clayton NY
Top

Next

Return to Trailer and Chassis Secrets

Who is online

Users browsing this forum: No registered users and 3 guests