Only 2 pieces to think about, no extra washers necessary
Great to hand tighten at first
Easy to use a hex key / allen key to tighten further
They look great, have a nice rounded surface
With our 8mm holes and M6 bolts, the nearly 8mm nut centers the end of the bolt, making for a better fit
But I’ve found some downsides:
Hard to find in New Zealand, is more expensive, so we had to out-source to China
It’s possible to “run out of thread” when tightening
For example, when using soft pine wood, the pine can compress, which means you have to tighten the nut further. I’ve encountered situations where the nut can’t tighten any further because it “ran out of thread”, which means you have to add a washer to offset the wood being compressed.
The fasteners can unscrew over time, especially when being moved around, such as on a bench or chair.
This means you have to periodically tighten the fasteners every so often, which can be less fun.
For more context, our initial choice of sizes, based on what we could find from AliExpress, was:
I’ve only personally used the the furniture bolts as you know, as I’ve been playing around with your Grid beam collection of parts.
I agree with your con’s for the furniture bolts, but I wonder if some of the con’s could be avoided. I have some ideas that I would like to try out personally with my own experiences of using the furniture bolts.
As for using them on Radiata Pine and the pine compressing, I think that is a hard one to overcome. Maybe if the bolt heads were larger, or if there was a tool to pre-compress the timber before joining them (don’t love that idea, but could be a solution )
One of the things I was thinking is making the beams out of a different wood with a higher density (wood density table) to reduce the compressing of the material. I know you’ve tried using Douglas Fir, and it has its own downsides like knots, but I wonder if using something like Douglas Fir, Oregon Pine in the states, or even oak, beech, or ash would be a better alternative, to mitigating the compression.
Once the compression is sorted, my solution to the loosening of the nuts is having the bolts pre-coated with something like loctite, so that when the bolts are tightens it keeps them from easily loosening. Like how FRP bolts are coated so they don’t vibrate loose on trailers.
My only not on hex bolts, Is I think they are a great solution for more industrial applications, like garage storage, or workshop fixturing, but they’re not super attractive for interior purposes, and like you mentioned if they are sticking out, you might snag your pants on it.
I was hoping to order from Dx market tonight and was calculating bolt an nut tolerances and I wanted to go with the nickel plated version of the nut instead of stainless steel. But dx market don’t sell a carbon steel bolt to go with it so I wondered what to do and my mind became a bit stuck on the nut, nut and rod solution… if so, I could have a lager rod selection and use the same nuts. a couple of hour later I’m give up for the night trying to find “nickel plated 70mm m6 threaded rod” on Ali Ex… everything is stainless steel or zinc plated. do you think zinc will be close enough or is it a recipe for corrosion and “money in the lake” as we say in Sweden (might as well have thrown them in a lake)
The fastener set on the picture was not sold in large quantities and way to expensive.
I might try to look for black screw and nut sets but then it’s a gamble if they work good like the DX market. All the ones I found in Sweden are casted and drilled so the hols in the nuts are/can be a bit of centered. I’m guessing dx market uses a lathe.
)
(might as well have thrown them in a lake)