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Big-screen TVs Cabinets Shelves Large mirrors Pot racks

by tomcam 10mo ago

what 10mo ago
Most people aren’t putting up their own cabinetry or shelving, they’ll hire a professional and they’ll know how to deal with the wall.
- IshKebab 10mo ago
  Most people aren't hiring professionals to put up shelves lol. And there is no "how to deal with the wall". It's fundamentally weak. Best you can do is Rigifix M8 bolts which are rated to about 25kgf as I said.
  - ajb 10mo ago
    Those seem to be for drywall. The strongest option is using resin to install some threaded rod, eg fis-v which is rated to 43kgf (shear load) in the lower of the two rated aircrete classes. That's because it spreads through the holes and therefore has a larger surface area of interface. The downside is that it's not removable.
    - IshKebab 10mo ago
      They aren't; they're for aircrete. https://www.buyrigifixonline.co.uk/rmd.pdf https://www.buyrigifixonline.co.uk/rmd.pdf > 43kgf (shear load) That seems really low for shear. The M8 Rigifix say 245 kgf for 1mm displacement in shear. Also I slightly misremembered the rating for pull-out - actually in 34 kgf, and they are applying a fairly generous 15% safety factor (i.e. tested ultimate strength was 224 kgf). But still, it sucks that you can't just use a normal wall plug and have to worry about this sort of thing.
      - ajb 10mo ago
        Hmm that's impressive for a single plug fixing. The above for fix-v is from their load table at https://fiproductmedia.azureedge.net/media/Load%20Tables/Load%20Tables%20fischer/LT_FIS-V-FIS-A_EN_T1.pdf https://fiproductmedia.azureedge.net/media/Load%20Tables/Loa... That's 0.43 kN which is 430N or ~43kgf. Comparing to the rigifix table they are using a heavier aircrete and a smaller safety factor, which would take fix-v up to 80kg but that's still a big difference. I wonder if there is a testing methodology difference, as usually resin fixings are considered stronger than plug fixings.
        IshKebab 10mo ago
        If it's just a threaded rod held in with resin then I expect the difference is in the hole size. The actual wall plug for the M8 Rigifix is 16mm diameter. Also the M8 bolt is inserted into a larger metal sleeve so it's less likely to bend. I don't know if that affects things though.

Big-screen TVs Cabinets Shelves Large mirrors Pot racks

by tomcam 10mo ago

Big-screen TVs Cabinets Shelves Large mirrors Pot racks

what 10mo ago

Most people aren’t putting up their own cabinetry or shelving, they’ll hire a professional and they’ll know how to deal with the wall.

IshKebab 10mo ago
Most people aren't hiring professionals to put up shelves lol. And there is no "how to deal with the wall". It's fundamentally weak. Best you can do is Rigifix M8 bolts which are rated to about 25kgf as I said.
- ajb 10mo ago
  Those seem to be for drywall. The strongest option is using resin to install some threaded rod, eg fis-v which is rated to 43kgf (shear load) in the lower of the two rated aircrete classes. That's because it spreads through the holes and therefore has a larger surface area of interface. The downside is that it's not removable.
  - IshKebab 10mo ago
    They aren't; they're for aircrete. https://www.buyrigifixonline.co.uk/rmd.pdf https://www.buyrigifixonline.co.uk/rmd.pdf > 43kgf (shear load) That seems really low for shear. The M8 Rigifix say 245 kgf for 1mm displacement in shear. Also I slightly misremembered the rating for pull-out - actually in 34 kgf, and they are applying a fairly generous 15% safety factor (i.e. tested ultimate strength was 224 kgf). But still, it sucks that you can't just use a normal wall plug and have to worry about this sort of thing.
    - ajb 10mo ago
      Hmm that's impressive for a single plug fixing. The above for fix-v is from their load table at https://fiproductmedia.azureedge.net/media/Load%20Tables/Load%20Tables%20fischer/LT_FIS-V-FIS-A_EN_T1.pdf https://fiproductmedia.azureedge.net/media/Load%20Tables/Loa... That's 0.43 kN which is 430N or ~43kgf. Comparing to the rigifix table they are using a heavier aircrete and a smaller safety factor, which would take fix-v up to 80kg but that's still a big difference. I wonder if there is a testing methodology difference, as usually resin fixings are considered stronger than plug fixings.
      - IshKebab 10mo ago
        If it's just a threaded rod held in with resin then I expect the difference is in the hole size. The actual wall plug for the M8 Rigifix is 16mm diameter. Also the M8 bolt is inserted into a larger metal sleeve so it's less likely to bend. I don't know if that affects things though.