Hi, I have built a custom cart made out of wood. I initially mounted small casters but I needed bigger wheels, so I bought a couple of 10" wheels that are normally used for hand trucks.
I am now lost on how to create a decent hub for those two wheels. I would rather not have a full axle as the distance between the two wheels is almost 5 feet.

This wheel hub will basically need to be attached or go through to a 4x4 pressure-treated post. I could reinforce the other side with a piece of metal. Any other advice? I spent a lot of time at Home Depot and on the Internet but I haven't really found something that would just work. Strange, it seems such an easy thing to do...

 

Does the hub of your wheels have bearings? If so, what is their bore?

 

A whole lot easier to suggest ideas with a picture.

 

Yes it has bearings, and a 5/8" steel rod fits perfectly.

 

You are perfectly right. The cart is at home, I will take a picture ASAP. But in fact, think you weed to put a wheel hub to a vertical 4x4 post. The wheels I got is this one: 10" Pneumatic Tire

 

Get some 5/8 threaded rod. Drill a hole through post and put rod through it. Will have to cut rod to length and use either washers on inside of wheel or find spacer, Double nut both ends or nuts will back off, Don't over tighten.

 

Here are some photos.

The relevant part of the cart:
[ATTACH=CONFIG]21026[/ATTACH]

And where the wheel should be:
[ATTACH=CONFIG]21027[/ATTACH]

 

Hi pugsl, yeah maybe it's the easiest. Do you think I could use a couple of long bolts then? Should I reinforce the wood with a couple of metal pieces?

 

Little late now but I never would have bought air filled tires, solid only. Some cheap or free one's off an old lawn mower would have worked.
You will soon see those cheap Chinese tires will not hold air for long and the bench will not be as stable.
I would not use treaded rod. A simple solid one piece steel rod, some cotter pins and washers is all you need to mount the wheels.
Picture how a wheel kit works on a generator.

 

The threaded rod as Pugsl mentioned is probably the easiest since you mentioned not wanting to run a solid axle all the way across. You'll want a nut & large washer on both sides so you can really tighten it squeezing the wood framing in between. It's not the best way to do a cart but it's about the easiest and best way to work with what you've already got.

If your wheel has an offset hub you can probably just slide it on the threaded rod with the convex (sticking out) side facing your frame. Then put two nuts on the outside. Run the first in until it touches the bearing then back it off a half a turn. Hold the first nut with a wrench then run a second nut up to it and tighten while making sure to not let the first nut turn. You do NOT want the nuts squeezing or putting side pressure on the bearing. If the wheel can move side to side a tiny bit that's OK. If your wheel has a centered hub you will need to install nuts, a bunch of washer or a piece of tubing cut to length to hold the wheel off so it does not rub on the frame.

 

Most threaded rod is grade 2. Not very strong.
A shoulder bolt would work better.
shoulder bolt | eBay

 

joecaption1, I have bought those tires because they were 3.99 each and I need to move the cart on some gravel and grass before it can reach its place on the flat concrete. I can afford to fill them with the compressor whenever I need to!

Oh, I like the idea of rod and cotter pins, it's how hand trucks do, even if they use a full axle. But I do not know a drill press, and even if I had it it wouldn't be the simplest to drill the pin holes... any suggestion there?

 

It's an offset wheel! No problem there thanks for the advice!

 

yes that looks great, but I would need to find one that is long enough... I will measure what I need.

 

If I use shoulder bolts I will need about 7 1/4 inches to go through wheel and post plus some more for the bolts. Who knows if I will ever find something similar!

 

If you go with a shoulder bolt you'll probably need one 8-9" long; 3.5" to go through the vertical 4x4 plus 1.5" for the side 2x4 add 2.375" for the wheel's hub then an extra inch for a nut & washers. With a shoulder bolt you won't be able to tighten the bolt to the frame independent of the wheel so you have to be careful to not squeeze the wheel. The bearings are rather tender to side loads.

 

So I got a 5/8" rod, pins and washers: it works quite well!
[ATTACH=CONFIG]21445[/ATTACH]
[ATTACH=CONFIG]21446[/ATTACH]

 

nice looking job. need more letters

 

Don't forget to at least lightly bend over your cotter pins. A few bumps and they might jump out.

 

You are right! I just wanted to test the system first before bending for good