I am going to mount a winch above my basement hatch and am considering how to do it in the best way. The winch is a cheap affair from Hornbach, it comes with brackets that seem to fit a 50 mm steel pipe.
I have a stud wall on one side, 70x45 with OSB+plaster on both sides. Where the bracket for the pipe is intended to land, it is reinforced with three studs in width, like a post. On the other side, it's lightweight concrete, quality "so-so."
My thought was to make wall brackets from a stud, 45x95, notched at the top, just enough, and fasten them into the wall with sturdy screws, like 8x80 or so. I was thinking of making the bracket about 200 mm wide along the wall and placing the pipe on these brackets. I planned to use three screws per bracket.
The question is, will this work? The intended load is about 300 kg at the most (the maximum load for the winch is 250 kg, plus the weight of the pipe and winch, plus a little extra). The support for the pipe will be about 40 mm (must have some clearance to the wall so that the pipe can be placed).
Second question is, do I need a 50 mm round steel pipe, or can I use a rectangular pipe like 40x30 (which is easy to find cheaply). The pipe would then stand on edge.
I know this can be calculated, but I don’t feel like learning yet another thing at the moment, so I’m hoping some kind soul knows directly how to input this into a program they have available.
I have a stud wall on one side, 70x45 with OSB+plaster on both sides. Where the bracket for the pipe is intended to land, it is reinforced with three studs in width, like a post. On the other side, it's lightweight concrete, quality "so-so."
My thought was to make wall brackets from a stud, 45x95, notched at the top, just enough, and fasten them into the wall with sturdy screws, like 8x80 or so. I was thinking of making the bracket about 200 mm wide along the wall and placing the pipe on these brackets. I planned to use three screws per bracket.
The question is, will this work? The intended load is about 300 kg at the most (the maximum load for the winch is 250 kg, plus the weight of the pipe and winch, plus a little extra). The support for the pipe will be about 40 mm (must have some clearance to the wall so that the pipe can be placed).
Second question is, do I need a 50 mm round steel pipe, or can I use a rectangular pipe like 40x30 (which is easy to find cheaply). The pipe would then stand on edge.
I know this can be calculated, but I don’t feel like learning yet another thing at the moment, so I’m hoping some kind soul knows directly how to input this into a program they have available.
To be able to calculate the pipe itself, the span (pipe length) is crucial. How far is it between the walls?tommib said:
Ah, I seem to have forgotten to write that.
1500 mm, give or take some decimeter. The winch will be mounted a little asymmetrically, perhaps 100 mm from the midpoint.
1500 mm, give or take some decimeter. The winch will be mounted a little asymmetrically, perhaps 100 mm from the midpoint.
Almost everything you can buy will work. I suggest VKR 3x50x50. It's easier to handle with a square cross-section (than a round one). The brackets will be sufficient.
Ok, thanks. I'll try to find somewhere to buy it then. I've found Stena stål in Spånga that sells to individuals but would rather find something in Söderort.
Anyone have any tips on places to shop? Preferably someone who doesn't want 1500 SEK for the pipe....
Anyone have any tips on places to shop? Preferably someone who doesn't want 1500 SEK for the pipe....
https://www.rinkabyror.se/artikel/galv-gangror-dn40-48-3x3-2mm-/
Haven't calculated, but 1 1/2 inch steel pipe is a simple alternative. 141kr/m at Rinkaby. If you know someone with some leftover from an old burton-ställning, you might get it cheaper.
Haven't calculated, but 1 1/2 inch steel pipe is a simple alternative. 141kr/m at Rinkaby. If you know someone with some leftover from an old burton-ställning, you might get it cheaper.
Checked that specific tube at RR, but like with many others, the shipping cost becomes unreasonable when you can't pick up the tube on-site. I've also looked at Thomann for truss tubes, but they are in aluminum, and even there, the shipping is too expensive in proportion to the tube.
Found a local company relatively nearby and sent them an email, let's see what they reply. Unfortunately, my experience is that when you come as a private individual and want to buy such small quantities, you either have to wait for a response or you don't get one at all.
Found a local company relatively nearby and sent them an email, let's see what they reply. Unfortunately, my experience is that when you come as a private individual and want to buy such small quantities, you either have to wait for a response or you don't get one at all.
Where I live, you can walk into any hardware store and buy this. Costs negligible money. It must surely be available in the Stockholm area. You should go up to 2-inch pipes to prevent too much flexing, even if it doesn't break.
Best answer
Now I'm a bit rusty on the calculations, but with the help of my old formula collections, I concluded that you should NOT hang 300 kg on a 1.5 m long 40x30x1.5 tube (the cheap one you linked to). With a point load of 3000 N in the middle, I get a bending stress of 489 N/mm^2, which could very well exceed the strength of the steel -- and I have ignored the shear stress. (I calculated with a section modulus of 2301 mm^3 if anyone wants to check my calculations.) The deflection I got was 22 mm.
The VKR 50x50x3.2 that was suggested has a section modulus of about 8600 mm^3 and is therefore four+ times better: Bending stress about 130 N/mm^2, which is safe. Deflection under 5 mm.
Thank you!
VKR 50x50x3 it is then. No point in being stingy here. The worst part is if I have to order online, the shipping costs twice as much as the tube itself.
I think that 300 kg is an overestimate. The heaviest thing I think I'll be lowering now is the heat pump, and it weighs 240 kg, but as mentioned, it's unwise to be stingy. Maybe I should have bought a sturdier winch as well, but it didn't seem reasonable at the time. My hope is that I can build it into a small box in the ceiling so it can stay there all the time, but we'll see what the wife says.
VKR 50x50x3 it is then. No point in being stingy here. The worst part is if I have to order online, the shipping costs twice as much as the tube itself.
I think that 300 kg is an overestimate. The heaviest thing I think I'll be lowering now is the heat pump, and it weighs 240 kg, but as mentioned, it's unwise to be stingy. Maybe I should have bought a sturdier winch as well, but it didn't seem reasonable at the time. My hope is that I can build it into a small box in the ceiling so it can stay there all the time, but we'll see what the wife says.
Oh no. The long goods fee was new to me. Rinkaby has previously been a reliable source for steel pipes at a decent price when they had a flat fee for orders and shipping, regardless of what you ordered.
But any forging company should be able to sell a pipe piece at a decent price, right?
Steel wholesalers usually have a fee for small orders, which is quite unfortunate if you're buying under around 100kg at a time.
But any forging company should be able to sell a pipe piece at a decent price, right?
Steel wholesalers usually have a fee for small orders, which is quite unfortunate if you're buying under around 100kg at a time.