building an axle?

[marlboro180]

Re: building an axle?

Actually, Great Stuff is supposed to be closed cell.

But I was not being completely serious with that suggestion. I agree with you, drain holes make the most sense.

yes, that is what they say, but it still holds water.

 

[elkhunter338]

Re: building an axle?

How to keep it from rusting on the inside.
As I said before I bought some 3500 lb round axles, I plan to weld or tap a fitting on to the axle, pressureiz it to about 25 psi and look for leaks, seal the leaks if found. and then no H20 will get inside. I plan to check every year or so and make sure the axles are sealed. I am in the process right now of getting a fitting on the axle. I am trying to weld a pip fitting and then drill a small hole in the axle, install a fititng that has a brass tire valve stem/ 1/4 pipe threads on it. If the welding does not work so well (all I have is a arc welder), then I plan to tap the axle for 1/8 pip threads. I will post a picture when I am successfull. I should beable to even leave say 20 psi of air pressure in the axle at all times.

 

[reelfishin]

Re: building an axle?

I build quite a few axles each year. One of the main benefits to using the heavier tubing is that it takes longer to rust away and become a safety issue. For a 16' boat, 1/8" wall would probably be fine strength wise, but it's more likely to warp when welding, it's more likely to develop stress cracks, and it's also far easier to crush if the U bolts are overtightened. For the minimal difference in cost, I build all my 2" axle tubes from 3/16" tubing, regardless of the weight class I need. Heavier axles get 1/4" wall tubing.
Lighter tubing is more accepted in galvanized steel for 1 1/2" axles.
For such a light trailer, and if rust through is a concern, you could also build a solid axle.
Several manufacturers use a solid axle beam, with the spindles welded on top to create a drop axle.
After seeing many factory or OEM built axles fail, I build almost 100% of my axles these days. After seeing some of the corners many brands cut, and some of the sub par welding, I have a hard time trusting a no name or imported axle.

 

[dazk14]

Re: building an axle?

Stacking 2 square tubes would be stronger and I've seen it done on many axles.

 

[reelfishin]

Re: building an axle?

Stacking two tubes only limits travel and or ground clearance.
Just use the right tubing for the job, prep and paint or seal it the best you can, and you will be all set. If your really concerned about corrosion, build the axle, drill two good size drain holes in the bottom and send the welded axle out to be galvanized. The two holes will allow the zinc to get inside of the axle tube, and drain back out when they dip it. Make sure you let them know to protect the spindles. You do not want galvanizing on the seal or bearing surfaces.

Myself, I don't bother, by the time corrosion takes any effect on the axle, the rest of the trailer is usually about due for replacement as well. If you clean and rust proof the tube before welding up the ends its about as good as it gets other than galvanizing it in and out.
You can also buy galvanized tubing, but you will ruin the galvanizing on the ends where you weld. In doing so, your all but guarantying that the first point of corrosion will be next to the weld, which will be outboard of the leaf spring when it's installed in most cases. If an axle is going to fail, having it fail in the middle rather than breaking off a spindle and losing a wheel is probably safer.
I've been making my own axles for 20 years, I've yet to have to redo one that I built.

 

[mucduc]

Re: building an axle?

im not to worried about the axle rusting thru. i have that sealed up pretty good. my biggest worries were the frame rusting thru. its not a huge problem because i have enough steel to make 4 more of these trailers. i know salt water can and will win a battle against the unprotected inside of the frame. i have thought about drilling holes and pouring ospho into each section of the frame and flipping the frame in all sorts of postions after all my welding is finished. then tap the holes and run a nylon bolt or galvanized bolt with rubber/nylon washer to seal the hole. i know ospho converts rust so i assume it will stop any more rust from acurring.

 

[dazk14]

Re: building an axle?

Stacking two tubes only limits travel and or ground clearance..

??

You've written some very astute comments...

Stacking/attaching 2 square tubes GREATLY increases it's strength, particularly in the Y axis.

If 3 guys can move this rig, double stacked tubes will be more than adequate.

The factor of safety is VERY HIGH in trailer production. Even 20 year old trailers tend to obviously bend and not break and they're VERY often being overloaded, while being subjected to a corrosive environment...

Heck, the manufacturers can't even put a placard on the trailer that lasts more than a hand full of years.

I would definitely drill some drain holes and coat the outer, but otherwise mucduc, I think you have a solid understanding of strength of materials - go build your trailer !!

Anyone skilled enough and shown the insight you possess will always keep an eye on their "Baby" - which is WAY ahead of what I've seen.