When you need to roll sheet or thin flat bar stock into an arc, you need a rolling machine, also known as a slip roll. If you’ve priced these lately, you’ll know that they can be rather expensive, especially if you are only going to use them for one or two projects. While building a fenced enclosure for his dog, [Tim] realized he could use steel fence posts and connectors to build his own slip roll for much less, and posted a video about it on his YouTube channel.
The key realization was that not only are the galvanized posts cheap and strong, but the galvanized coating would act as a lubricant to reduce wear, especially when augmented with a bit of grease. The build looks pretty straightforward, and a dedicated viewer could probably re-create a similar version with little difficulty. The stock fence connectors serve double-duty as both fasteners and bushings for the rollers, and a pair of turnbuckles supplies tension to the assembly.
The one tricky part is the chain-and-sprocket linkage which keeps the two bottom rollers moving in tandem. [Tim] cut sprockets from some plate steel with his plasma cutter, but mentions that similar sprockets can be found cheaply online and only need to be modified with a larger hole. Although most of the build is held together with set screws in the fence post fittings, the sprockets appear to be welded to the galvanized pipe. We’re sure [Tim] knows that welding galvanized steel can lead to metal fume fever, so we were hoping the video would caution viewers to remove the zinc coating on those parts before welding.
[Tim] demonstrates forming some 4 mm flat steel into circles, and the operation seems easy enough, especially given the inexpensive nature of this build. Overall, this seems like the sort of thing we could see ourselves trying on a lazy Saturday afternoon – it certainly seems like more fun than building a fence with the parts, so be sure to check out the video, after the break.
Bending metal is great, but if wood is more your thing, check out this plywood bending jig.
Thanks to [Turtle] for the tip!
Sprockets like what he uses there are available at Surplus Center here in the US. https://www.surpluscenter.com/Power-Transmission/Sprockets/ although I’d wager that some sprockets off of a bike rear cluster would work just fine…comes with the necessary chain, too.
Could he narrate all Hackaday videos? Come to think of it, could he narrate all the videos I watch?
Mmmm, great hack, even if I don’t really need one, I’d love to have it, and I’ll give a try that way.
Got a lot of useless bicycle sprockets somewhere in the workshop.
Anyway, when you have a tool, it happens that ideas to use it comes more often than when you don’t ;o).
Very nice! Wondering if the gap between the bottom 2 rollers makes it difficult to bend the beginning and end of the bar stock? No way around (pun, ha!) that, though, I guess (?).
Also, will it bend a cone in a piece of sheet?
With the video running in the background, I’m picturing a Wallace and Gromit cartoon. Can we get a remix?
This is really good. 80 out of 100 hacker points. 5 extra points for having livestock in the workshop but -2 for CNCing his chainrings when he could have scavenged them from old bicycles :-)