wheels + axle -- like a DIY hand truck

July 13, 2022 7:17 PM

I want to make a heavy tallish shelf that can be tilted back and rolled like a hand truck (it will be holding very heavy items that will be fastened in place). The wheels part is stumping me, since I've only ever worked with casters and I think I need wheels more like a wheelbarrow/hand cart/hand truck. Like this -- two wheels connected by an axle. Where do people get these things, especially the axle and whatever attaches the wheels to it?

I can find wheels at Lowe's / Home Depot, but I'm not sure of the best way to attach them. I mean, I think I can use thick wood, structure the item so that things will be supported correctly, and drill holes through the right place -- but what about an axle? And fastening the wheels to the axle?

I found a tutorial that seems to be using a metal rod that is threaded over its whole length and then slipped into a PVC pipe -- but that seems like a hackier solution than I'd want, plus I'd like the whole thing to look a little more polished and intentional.

I know I could possibly find an old... wheelbarrow? Go-kart? and get the wheel structure from that, but I'd like a solution that is reproducible and standardizable.

I'd also like to avoid buying specialized metal cutting tools. Or any more tools, if possible.

So, I'm wishing for some kind of kit, or pre-created axle assembly, that will work for wheels about 12-22" apart (30-55 cm), with the wheels being, I don't know, 4" to 12" in diameter (I'm not picky about the size just now). And I'd like it to be $30-ish, but just tell me what exists or how to search for it, and I'll figure out the cost later.

If normal practice is buying a rod of some kind and making it fit and/or doing something to the ends, I'd like to know about that too.

Thank you!

posted by amtho to Grab Bag (27 answers total)

Maybe you should just get a pallet dolly that can handle a few tons? I know the price is way over your budget, but then it's designed to handle 1.5 tons.
posted by kschang at 7:37 PM on July 13, 2022

Response by poster: I'm making something that can be parked in a living room and used as a shelf/cabinet (and I hope to make it somewhat elegant looking), but that can be rolled to a new location when needed.
posted by amtho at 7:50 PM on July 13, 2022

Response by poster: ...and yes I have already thought of just making an all wood structure and moving it with a dolly when needed. That's a known solution which doesn't require asking a question :) I'm trying to make something new.
posted by amtho at 7:51 PM on July 13, 2022

I suspect you can find everything you need at Grainger, if you're in the US. They certainly have a wide selection of wheels and casters of all sizes. If you don't need it to tilt, I'm sure you could find some large casters that would fit the bill. You could build the cabinet such that the casters aren't really visible by having the bottom shelf sit above the level of the casters and building a "skirt" around them.
posted by wierdo at 7:55 PM on July 13, 2022

When I did something similar a little while ago, I used these wheels, a 1/2 inch aluminum rod from Lowe's, and these end cap nuts.

One thing to note is that Home Depot sells a similar 1/2 inch rod that is actually 13mm, and which won't fit into the holes in the wheels. Bring your calipers when you're shopping.
posted by Hatashran at 7:57 PM on July 13, 2022 [2 favorites]

Response by poster: I did look at Grainger. I have no idea what to order. I tried searching for 'axle' and 'wheel kit'... didn't help. I'm not convinced they have what I need.

Hatashran! That's promising -- I'd love some smaller wheels, but it's a start.

At least I know that you were able to make something work with only those three parts and didn't need something else.

Does anybody know if Lowe's or Home Depot will cut metal rods to the desired length?
posted by amtho at 8:09 PM on July 13, 2022

I don't know if they will, but a hacksaw got through it in just a minute or so. And the end cap nuts cover the cut so it doesn't look bad.
posted by Hatashran at 8:11 PM on July 13, 2022 [1 favorite]

Harbor Freight might help.
posted by at at 8:12 PM on July 13, 2022

Depending on the weight/size of the shelf, it may not be necessary to have a dedicated axle. For a hand truck, I think the primary purpose of the axle is for structural stability when you have the wheels that far from the frame, which in turn is necessary to put the wheels under the center of gravity when tilted at a more comfortable angle. If your shelf isn't too tall, or you're willing to put up with a bit of awkwardness to balance it, you could use something like these tilt casters, or any of these casters intended for road cases. (Not vouching for these specific vendors, just representative search results.)

But do give a bit of thought to how far you will be able to tilt the shelf before it overbalances and you wind up lifting the entire weight like a wheelbarrow. This depends on the pivot point, which will be the axle (or the theoretical axle, if you use individual casters).
posted by yuwtze at 8:30 PM on July 13, 2022 [1 favorite]

DIY Hand Trolley

DIY Cart
posted by oceano at 8:31 PM on July 13, 2022

Could you make a chamfer on the back bottom of the cabinet (like this Ampeg bass cabinet) and mount the casters right to the angled part?
posted by jonathanhughes at 8:33 PM on July 13, 2022 [2 favorites]

If I'm understanding your shelf project, if you're wanting to tilt+roll it, I'd probably lean toward a design similar to this appliance dolly, with a swing-out/stowable set of casters in addition to the "main" wheels, to hold the item at a fixed angle, and reduce the weight you need to carry (once tilted, you just have to push it, not hold the weight or stabilize it as much).

Or, perhaps retractable/drop casters, like workbench casters that are normally folded up, but when you fold them down and step on the lever, it cams the caster down, picking the furniture up off the floor just enough to let it roll.
posted by xedrik at 8:53 PM on July 13, 2022 [3 favorites]

Response by poster: Since y'all seem interested:

The unit will probably be around 5' high _excluding_ bottom clearance. I'm leaning toward adding 10" on the bottom to make room for wheels.

It's for holding a lot of cast-iron clamps and other tools (like a lot of clamps) (heavy clamping ends on the bottom for stability), but my tools are stored in my living space -- so I want it to be like a shelving unit that I can add a bit of finesse to -- and might need to migrate. The thing can be heavy and sturdy.

I'll need to be able to roll it up and down fairly steep ramps, I'm anticipating, or maybe to have two people carry it up and/or down stairs.

oceano - I found the hand trolley -- it's cool! I hadn't seen the cart.

re: casters -- I don't trust that casters attached by screws going into wood can handle the kind of slouchy weight they'd have to handle. I'm hoping I can make the wheels thing work. It also seems like having one long axle would make the whole thing more stable than having the wheels attached separately.

--

If this works well, I can see myself making multiple shelves with this as a model.

Also, I've always been mystified by how to make/buy/set up a wheel axle (I think about gears a lot, too), so I'm super interested in learning how to do this right.
posted by amtho at 9:11 PM on July 13, 2022

Re cutting metal rods: If you already have tools already, that's just a hacksaw, and maybe a file to clear up the ends.

For casters, shear strength of a single #8 steel screw is likely greater than 80 lbs. 4 of those holding on a caster, and any caster #8 screws will hold will fail before the screw does. A Simpson 1/4" deck screw is good for 150 lbs or more, depending on your casters a couple of good lag screws will. well... if you think 2 people are gonna carry this, you can definitely fit casters to it.

But if you stick with the through-axle notion, I'm seeing a whole bunch of different "related products" wheels recommended off of Hatashran's Amazon link, from smaller plastic lawnmower wheels, on up.
posted by straw at 9:55 PM on July 13, 2022

Best answer: I recently put together some tricycle axles with thru-axle bike hubs that are basically a high-tolerance version of hand-truck hubs. My approach (slightly simplified) was:

- Bicycle hubs with 12 or 20mm dia. axle holes. You don't need the tight-tolerance, high-speed bearings these have, so you could use hand-truck hubs that will probably have a 1/2" axle hole or something like that.

- A steel tube with an O.D. suitable for the hub axle. This is the primary axle. I got mine from McMaster-Carr and cut them to length with a hacksaw.

- A threaded rod with an outside diameter to fit inside the steel tube above, and nuts & washers to go on the end. This keeps the wheels from sliding off the end. Again, ordered from McMaster and cut to length with a hacksaw. Instead of the threaded rod you can use shaft collars to keep the wheels from sliding off the end, but it's harder to get them really tight against the hub. That may not be an issue for your application, though - moderately tight is probably sufficient.

- Something to keep the wheels from sliding inward - for me, this was another metal tube (steel or aluminum, whichever was cheaper) large enough to sleeve over the axle tube. You could also use shaft collars. If you use mountable shaft collars they can double as the thing that attaches your axle to the shelf.

It may be overkill and over budget for your application - I built these to carry a person and a bunch of cargo for thousands of miles. I think it's a snazzier version of the PVC over a threaded rod that you described above. It works, though!

On further consideration, I'd probably just use the threaded rod as the axle. To make it look nicer I might put whatever cheap metal tube I could find over it, or just put nuts to the inside of the wheels and hide the threaded rod inside some kind of wood enclosure? Acorn nuts on the ends will look good too, at the expense of being slightly wider. Maybe use several surface-mount nuts along the length of it for attachment; they're a little cheaper than face-mount shaft collars.

One possibility for smaller wheels is scooter/skateboard wheels, but those tend to be sized for thinner axles and I don't know that I would trust them with heavy loads.
posted by sibilatorix at 10:50 PM on July 13, 2022 [1 favorite]

Response by poster: I just estimated the payload weight at 166 pounds (plus the weight of the construction lumber). I have 166 pounds of clamps, y'all. I like the cast iron ones.

I'm not worried that the screws will break; more that the wood around the screws will loosen over time, or maybe that a caster plate will bend.

Plus, a larger wheel seems like it might be more stable / easier to roll?
posted by amtho at 10:50 PM on July 13, 2022 [1 favorite]

Hm, couple of followup thoughts:
- Any reason this needs to be a single unit? My usual philosophy for this sort of thing is "if you're building something to heavy to carry, break it up into lighter modules." The trikes I mentioned above broke that rule, and I have regretted it!
- 166lbs + lumber might actually work with scooter wheels if you support both sides of the wheel. Also roller skate wheels - you can probably get 8 of those for $10 at a thrift shop.
- Larger wheels will roll over larger bumps with less effort. Size your wheels based on the bumps you expect to encounter.
posted by sibilatorix at 11:04 PM on July 13, 2022

Two observations:

- You may be thinking that your wheels would be fixed to the axle and the whole assembly would rotate together, but this is a bad idea, since it would make it nearly impossible for your object to turn. One of the wheels would have to slip, skid, or deform. Having the wheels rotate independently on a fixed axle will make this much easier, and also it will let you buy wheels with built-in bearings which mean that all the moving parts will come in a single package.

- 50lbs is not very much load at all, at least not for metal parts and wheels. I'm having a hard time finding wheels rated to LESS than 150lbs.

I would get some polypropylene wheels with roller bearings (maybe 2781T415) from McMaster-Carr. Then, if you want to do a through axle, some steel tubing with bumpers at the ends and shaft collars holding the wheels in place. Don't worry if the wheels have a few sixteenths of an inch of play -- that will make turning easier. But a better bet would just be getting some caster axles (e.g. 23595T16) of the appropriate diameter along with washers and spacers as necessary.

As for securing the axles to the wood, if you are very worried you can buy some mounting brackets (e.g. 1030A15). Secure them to the wood with bolts on the corners, and drill a hole through for your axle(s). These will transmit the force through four bolts instead of just one, meaning the shear force against the wood at each point will be much less.

Looks like from McMaster-Carr this will all cost you in the neighborhood of $50. The rule of thumb for them is "too expensive for production but great for prototyping".
posted by goingonit at 4:38 AM on July 14, 2022

(sorry, to be clear I meant 150lbs isn't much load at all!)
posted by goingonit at 4:50 AM on July 14, 2022 [2 favorites]

Best answer: If you open the photo of that hand trolley you linked in its own tab and scale it up a bit, you'll see the hardware that fastens the wheels to the axle.

It's hard to tell from that picture whether the wheel hubs are fitted with ball or roller bearings or not. I suspect that they probably would be, given that this is a trolley whose entire point and purpose is to spend its service life moving things about. For a machine that only needs very occasional movement, like the wheeled shelf unit you're proposing, proper bearings are overkill: simple hubs spinning on a smooth steel axle with a bit of grease in between will be plenty good enough.

Don't design in an aluminium axle. Though faster to cut and file than steel, aluminium won't be anywhere near as stiff or wear-resistant for any given axle diameter and you don't want your wheels to deflect sideways under load.

So first pick your wheels, then find a bit of plain (not threaded) steel rod that's a good fit for the holes through the hubs. Ideally you want a fit that's loose enough to allow the wheels to spin freely on a grease layer, but not so sloppy that they actually wobble on the axle. A little wobble won't hurt, though, if you can't find a perfect fit.

For fixing the axle to the furniture, I wouldn't make holes in the steel. Instead I'd cut a rebate or channel into the back of the shelves for the axle to sit in, then hold it firmly into place with suitably sized U bolts.

For fixing the wheels to the axle, I'd use the same system that the linked hand trolley does. First fix the axle into place on the shelf unit as above, then put a washer stack on each end where it sticks out past the sides of the shelf unit. Use enough washers in each stack to space the wheels far enough from the walls that they'll never rub. Slip the wheels on, then another washer, then make a dot on each axle with a Sharpie where it sticks out past the last washer.

Take off all the washers and wheels, use a centre punch to turn each Sharpie dot into a dimple, then drill a hole all the way through the axle at those point. Use a hacksaw or powered cutting wheel to trim the axle so there's about 1/4" of steel left between the end of the axle and the hole. Use a metal file to smooth off the cuts and chamfer the cut ends. Smear a bit of grease on the axles and on the washers that will make up the washer stacks, fit the washer stacks and the wheels and their outermost washers, then use split pins through the holes you drilled to retain the wheels.
posted by flabdablet at 5:01 AM on July 14, 2022 [1 favorite]

Best answer: If you can't find split pins you can achieve the same kind of fixing by cutting the heads off some suitably sized nails, slipping those through the holes, then using a hammer to tap each one into a Z bend so they won't fall out again. The idea is just to retain the outermost washer, which is actually what the wheel hub will bear on, and as long as that washer can't slip off over whatever you've bent through the retaining holes you're all good. But the split pins will certainly look less agricultural.
posted by flabdablet at 5:13 AM on July 14, 2022

Response by poster: This is exactly the kind of technical know how I was hoping for!

In my dream of dreams, the axle with the holes made in it already exists and comes with matching wheels, pins, washers, etc. ... maybe one end has a cap fastened on it already, so it just needs to be threaded through stuff and another cap put on.

I'm getting the impression that that doesn't exist, though.
posted by amtho at 5:40 AM on July 14, 2022

Cutting a half-inch steel rod to length with a hacksaw, cleaning up the cut ends with a file, and drilling a couple of 3/16" holes through the ends with a high-speed steel twist drill should be well within the technical and patience capabilities of anybody with enough woodworking skills to design and build a sturdy shelf unit. It ain't rocket science. And doing the trimming and drilling after the axle is firmly fixed to the furniture also means you won't even need a metals-capable bench vise.
posted by flabdablet at 5:42 AM on July 14, 2022 [2 favorites]

Incidentally, if you do end up with roller bearings in your wheel hubs, the only differences in the assembly procedure above will be that a slightly tight fit of hubs onto axles is preferable to a slightly loose one, and you won't need the grease.
posted by flabdablet at 5:44 AM on July 14, 2022

technical know how

It feels kind of weird to have stuff that seemed obvious to me as an eleven year old building my first billy cart described as "technical know how" but I'll take it :-)
posted by flabdablet at 5:50 AM on July 14, 2022 [1 favorite]

Response by poster: It is! But I also classify "how to change the paper towel roll" as technical know-how (making a hole in metal is more advanced -- I wouldn't have known to make the dimple first!). Anything is obvious if you already know how to do it!
posted by amtho at 6:09 AM on July 14, 2022

Fair call.

Yes, a proper dimple from a centre punch makes all the difference between a nice straightforward drill hole and a nightmare of sideways wander and swearing, especially when starting a hole on a convex surface like an axle rod or pipe.

And yes, there's more to "just drill a hole" than just drilling a hole. Luckily this is 2022 and YouTube is a thing now! But you've only got two holes to drill, a cheap and small but not teeny tiny bit to drill them with, and no real requirement for high precision in angle or positioning. As long as you get them properly started with a centre punch you could have the worst technique in the world and still get a workable result.
posted by flabdablet at 7:12 AM on July 14, 2022