Unistrut Caster Base

[Modern Jess]

I was going to post this in my workshop build thread, but figured that it would probably be of general interest to a lot of people.

I needed a beefy base to hold a couple of card file cabinets in my shop. I had each of them on individual caster bases made of 2x4s, but the design ended up wasting a bunch of valuable space. I figured I could save 10 inches of wall space by combining them on a more efficient caster base. However, the weight of two fully-loaded 3x5 card cabinets gave me significant pause. I didn't think 2x4s with twice the weight and twice the span were going to cut it.

So this is my design for a Unistrut / Superstrut caster base.

Layout of the caster mounting point:

The casters I ended up getting for this project were a bit large -- 700 pound capacity apiece. This made the mounting point a bit awkward. I found I could get the casters closer to the corners if I indexed the bolts:

I use strut channel pretty regularly, so I had some scraps lying around. All cut to size:

Squaring it up was a giant pain in the ****.

Caster mounted:

Voila! A mobile unistrut caster base! (Note that this pictures shows the locking casters oriented wrong -- I later swapped two so that the locks would both be on the front of the base)

And here's what I eventually managed to wrestle on top of it. I even managed to bolt the two cabinets together through the knockout holes that were apparently intended for just such an occasion:

 

[memphisnate]

Sweet setup! Is the weight of the cabinets the only thing keeping them on the base or did you connect the bottom cabinet and the base together?

 

[srmofo]

pretty cool, but I think I would have put a couple of welds on it to keep it all together.

Id like that for a parts cabinet. I just cant find any card catalogs at a reasonable price

 

[Trey T]

Pretty cool. My last workbench, 10ft long, had a Unistrut frame.

How did you attach the cabinet to the base?

 

[Modern Jess]

Had to re-upload a couple of those files -- got corrupted somehow. If you're seeing garbage or very large images, hit reload a couple of times.

 

[Modern Jess]

pretty cool, but I think I would have put a couple of welds on it to keep it all together.

I'm pretty wary of welding on galvanized. Plus, I don't have the power in my shop to run my welders at the moment (that's a separate project) so it's kind of moot.

Id like that for a parts cabinet. I just cant find any card catalogs at a reasonable price

Yeah, I kept hunting and hunting for these. What used to be cheap throwaways in the 80s and 90s (when businesses were moving their customer databases to computers) are now highly-sought-after by DIY types. I ended up paying a bit too much for these, as I was tired of searching.

 

[Modern Jess]

How did you attach the cabinet to the base?

Gravity.

I am thinking about drilling a couple holes in the bottom edge (on the underside) and bolting through the slots in the strut channel, but I'm worried I'll weaken the cabinet structure. These cabinets weigh a metric bum-ton, so even with empty drawers, they are very, very planted.

One other possibility would be to bolt some strips of steel bar stock (say 1/8" thick or so) to the sides of the channel, creating a lip so that the cabinets can't slide off. If I did that on all four sides, I think it would be "good enough".

 

[DonPowers]

Nice caster base!

I love unistrut, its like an adult version of an erector set, you can build lots of stuff with it.

 

[Strouty]

What are the castors rated for? I would be interested to find some like those. Where did you get them?

 

[Modern Jess]

What are the castors rated for? I would be interested to find some like those. Where did you get them?

They're rated for 750 pounds each. I got them from McMaster: Plain and Locking.

McMaster shows multiple versions of this same item number for some reason -- I purchased the ones with 1/2"-13 long stems. I originally was going to bolt all the way through the strut channel (and several plates) but my design changed, so I swapped the 4" stems for 2" ones. They're just bolts through the caster assembly.

 

[Trey T]

@$140 worth of casters but @3000lbs capacity. Man, that's strong.

 

[akdiesel]

Modern Jess

That looks great. I am going to use your design. I have done both welding and bolting with unistrut. Welding will cut costs in that you don't need as many parts but modifications may need to be done later on and I have not had any issues with bolts or brackets coming loose with the lock nuts Unistrut makes or others like it.

 

[1/2 Cup]

Top job Jess thanks for posting.

 

[Modern Jess]

@$140 worth of casters but @3000lbs capacity. Man, that's strong.

Yeah, I might have overdone it a bit on that part. The choice of caster was mostly based on getting a long-stem 1/2"-13 thread mount. Knowing what I know now -- and with a different design -- I could have used something a bit less beefy (and pricey). Lesson learned.

 

[Vegaman_Dan]

I would not have thought to use unistrut for a base like this. Interesting idea and one I'll have to squirrel away for ideas later.

With the welders handy, I'd have whipped this out in square tubing, but there's something just cool about all those bolts, plates and pieces.

 

[Modern Jess]

With the welders handy, I'd have whipped this out in square tubing, but there's something just cool about all those bolts, plates and pieces.

I probably would have done the same, if I could fire up my welders.

 

[sakurama]

Nice solution - especially for those without welders, which are most folks. I've never used unitstrut but seeing your varied uses has thinking of ideas.

Nice!

Gregor

 

[qctech]

Just got two radio shack cabinets from a closed store and was looking to do something like this with Them real nice job!

 

[Sbrune]

Great idea! This is exactly what I'll use for the card file I just acquired. Question did you use 3/8 or 1/2 bolts?

 

[metalmagpie]

I recently made a rolling base. Mine was designed to carry a machine low to the ground; a lowboy design. It isn't anything special but I like the curves I came up with.

It was designed for a biggish arbor press. Here's the machine on the base:

Still, I like the Unistrut version. Wondering how thick your caster support plates are.

metalmagpie

 

[Modern Jess]

Great idea! This is exactly what I'll use for the card file I just acquired. Question did you use 3/8 or 1/2 bolts?

I used 1/2" bolts, both because "overbuilt" was the order of the day and because I have a good supply of 1/2" strut channel hardware (rotating nuts, bolts, brackets, etc).

 

[Modern Jess]

I recently made a rolling base. Mine was designed to carry a machine low to the ground; a lowboy design. It isn't anything special but I like the curves I came up with.

Wow, low is right. That's pretty impressive.

Still, I like the Unistrut version. Wondering how thick your caster support plates are.

I think you're referring to the struct channel corner brackets? They look to be just shy of 1/4", say 7/32".

 

[WhoWhatNow]

I recently made a rolling base. Mine was designed to carry a machine low to the ground; a lowboy design. It isn't anything special but I like the curves I came up with.

It was designed for a biggish arbor press. Here's the machine on the base:

Still, I like the Unistrut version. Wondering how thick your caster support plates are.



metalmagpie

I built a similar base for my Bridgeport.

 

[metalmagpie]

I like that Bridgeport base! Almost nothing at all in front of the machine where your feet are. And very solidly and competently built. I really enjoy seeing all the different ways people solve the same problem. More than one way to skin a cat indeed.

MM