Building a trailer

[Whatswrong]

LD ,I'm not an engineer ,it would never occured to me 2 3 inch beams would be less than 1 6 inch ,i can see where 2x4 x1/4 would be stronger .To strenghten it that seems fairly easy if required ,I could run a 1/4x4 flat bar on each side of the main beams and I had already contemplated doing that on the out side to cap the crossmembers.As i said earlier this is my first flatbed trailer and any comment will be considered helpfull.I don't anticipate more than 8000 lbs very often if ever ,

 

[LD1]

LD ,I'm not an engineer ,it would never occured to me 2 3 inch beams would be less than 1 6 inch ,

I am not sure what you mean by this??

Some pics, even if in the form of a crappy microsoft paint drawing, would be extremely helpful.

IF you stacked the two 3" beams on top of one another, then no a singgle peice of 6" channel is not as strong. BUT, if side x side, YES, even 5" channel is going to be stronger.

And while capping the sides with 1/4" plate for strength sounds good, it isnt going to add as much strength as you think. Beams get their strength based on 2 main factors, how much mass is at their extremes, and how far appart their extremes are. Look at I-beams, or channel Iron for example. They have a lot of mass at the top and bottoms of the beam. (flanges). And the middle (web) is only their to hold them appart and does little for strength.

A 1/4" x 4" plate doesnt have any mass at the top and bottom edges.

Not to mention that would add another ~3.43lbs/foot to your 3x3, making your side rails of the trailer come in at over 10lbs/foot.

And all of that still would not be as strong as 4" or 5" channel that would weigh half of what that does.

For the cost of your "reinforcement" 1/4"x4", you could probabally just but the channel and be done. Save the 3x3 for crossmembers or another project.

 

[lostcause]

just reading the first few posts a little more, it made me think about a couple things:

you mentioned about the wheels being higher than the deck and needing about 6" of fender, and you mentioned having already welded up an 8x16 frame. are you having the fenders and wheels totally on the outside of the trailer frame, or are they going to be sticking through the deck, near the edge? if you have an 8' wide deck you would have to have the wheels stick through or else you're going to be about 9'6" (or wider) with the fenders on the outside of the frame. 7' or a little less is about all you can manage for a deck width if you put the fenders on the outside.

if you are working on making the trailer functional to the limit of the weakest link, then you are looking at around a 12k capacity? maybe for a small excavator 16' would be good, but if you are planning on using it for vehicle / tractor hauling i'd go for 18 or 20 feet in length. that's a better proportional length for the weights of trucks or tractors with implements. i know you said you had it all welded, but the good thing about welding and grinding is that you can change it fairly easily.

as mentioned many times, 3" box isn't the best thing for a trailer. section depth is king here. thickness to a point, but 3/16-5/16 material is about the max needed for trailers of this type. extra thickness is not a substitute for a lack of depth though. if that's the available section size to work with, run a second rail as a subframe on each side, somewhere toward the outside and you'll get a lot more stiffness out of it. my personal preference is channel for trailers because you get good strength to weight, and around here a thin walled tube frame won't always hold up to prolonged exposure to road salts - they often will get corrosion from the inside out.

 

[Whatswrong]

I just finished taking some pictures with my camera but will need help to post them ,the overall width is about 98" 82" between the wheelwells.The hitch pole and A-frame braces are 1/4 inch this gives a third beam for half way back ,based on all the recommendations for chanel or I-beam I may have just gained the welding expierience and not a lot of trailer but hopfully it will haul our 35hp tractors occasionally .If it has any value I built about 3/4 frown in the main beams ,I based that on the fact that any Hi-boys I'm around have a lot more than that,I realize that won't add strenght just did it to accomodate any sag from the load on it.

 

[LD1]

I just finished taking some pictures with my camera but will need help to post them ,the overall width is about 98" 82" between the wheelwells.The hitch pole and A-frame braces are 1/4 inch this gives a third beam for half way back ,based on all the recommendations for chanel or I-beam I may have just gained the welding expierience and not a lot of trailer but hopfully it will haul our 35hp tractors occasionally .If it has any value I built about 3/4 frown in the main beams ,I based that on the fact that any Hi-boys I'm around have a lot more than that,I realize that won't add strenght just did it to accomodate any sag from the load on it.

Load the pics up on the your computer. The when you click "post reply" to this thread, down at the bottom should be a button that says manage attachments. Click that.

This should open a new window with about 4 blank boxes at the top. Click the "browse" button. Go find your pics wherever you saved them at. double click them one at a time and you should see its "address" appear in that white box. Do the same with the next blank box until you have selected all of your pics.

Now click the "upload button". This could take awhile if they are large pics. Once they upload, the boxes will be blank again, and you will see them attached below the white boxes in blue:thumbsup: At this point, you can upload more pics if you want. When done with that, click "close this window". It will take you back to where you can type a reply. The just click submit new thread and your pics should appear.

 

[Whatswrong]

I just finished taking some pictures with my camera but will need help to post them ,the overall width is about 98" 82" between the wheelwells.The hitch pole and A-frame braces are 1/4 inch this gives a third beam for half way back ,based on all the recommendations for chanel or I-beam I may have just gained the welding expierience and not a lot of trailer but hopfully it will haul our 35hp tractors occasionally .If it has any value I built about 3/4 frown in the main beams ,I based that on the fact that any Hi-boys I'm around have a lot more than that,I realize that won't add strenght just did it to accomodate any sag from the load on it.

I meant to say phone camera

 

[LD1]

I meant to say phone camera

Do you know how to load them on the computer?

Does it have a SD card that it stores the pics on?
If so, it is easy to upload them onto the computer. If not, you will have to e-mail them to yourself provided you have texting.

Or you can buy an adapter to plug the phone into the computer.

But if no adapter, no card, and no texting, I am afraid they are going to stay on your phone.

 

[deepNdirt]

a 4th option would be if you have a printer hooked to you computer that also has a built in flash card reader, this is a part of your system hardware and will upload the Picture into a file on you computer...

 

[Gary Fowler]

I think if I wanted to strenghen the trailer frame, I would use the flat bar like a truss underneath. You could weld some of your 3" box tubing about 3" long to the bottom side about 3 feet from each end then weld the flat bar to the end and 45 it down to the first box and weld it to that one,continue to the next one, weld it then back up to the frame with at least 3 inches of weld to the frame. That would require that the flat bar break before the frame bent which is about as strong as you can make with minimum weight. You may also want to put in a stiffener in the middle if it looks like the flat bar is flexing. You dont want it to move or fatigue cracking may occur. I did similar to a 40 foot cotton hauling trailer using drill stem sucker rod and welded with 7018 to a 4" channel on each side. I did have a 3rd 4" channel in the middle but without the truss. It worked well and never had a weld failure

 

[Whatswrong]

I'm going to have to buy more "stuff" next weekend.I used the webcam this afternoon also but the power was off so they are to dark to be usefull ,I believe.