Need to level joists, totaling up to nearly 100sqm. Some parts have more modern 50x180 joists, others are sawn timber.
Shimming with masonite and lumpapp inserts, I think, will drive us insane quite quickly. The joists are warped to varying degrees and there are height differences of up to 35 mm. Adding a joist on the side works in some places but far from all. Additionally, we prefer to screw-and-glue the chipboard on about 1/3 of the area to stiffen the inter-joist.
Therefore, considering building a large router sled inspired by Jesse Mullen where you place "rail joists" on existing joists and align them level in both directions. Depending on the heights, trim will be added and then planed flat. Possibly rough adjustment with a power planer first.
Planning to rent the most powerful router possible and use a router head with interchangeable cutters, like this one: https://www.wealdentool.com/acatalog/Online_Catalogue_Surface_Trepanning_Three_Wing_928.html
Length x width will be in the range of 4x3 meters in that case.
Does the panel think this is feasible, or is old school alignment still the fastest and best option?
Shimming with masonite and lumpapp inserts, I think, will drive us insane quite quickly. The joists are warped to varying degrees and there are height differences of up to 35 mm. Adding a joist on the side works in some places but far from all. Additionally, we prefer to screw-and-glue the chipboard on about 1/3 of the area to stiffen the inter-joist.
Therefore, considering building a large router sled inspired by Jesse Mullen where you place "rail joists" on existing joists and align them level in both directions. Depending on the heights, trim will be added and then planed flat. Possibly rough adjustment with a power planer first.
Planning to rent the most powerful router possible and use a router head with interchangeable cutters, like this one: https://www.wealdentool.com/acatalog/Online_Catalogue_Surface_Trepanning_Three_Wing_928.html
Length x width will be in the range of 4x3 meters in that case.
Does the panel think this is feasible, or is old school alignment still the fastest and best option?
Would have liked to have a sled when I aligned a significantly smaller room, about 18 sqm, with twisted beams, so I say go for it! But the question is if it's not faster to cut most of it with a circular saw and then plane the ones you can't attach a new batten to the side. Don't forget to document if you proceed with the sled 🙂
What do you mean by circular saw? Running it along the side of the studs? 🤔 How do you keep the level right then?
Most of the beams will probably need to be sistered a bit to get everything at the right level, and the question is whether you should do that first or straighten first and then sister... Either way, there's a big risk of nails...
Most of the beams will probably need to be sistered a bit to get everything at the right level, and the question is whether you should do that first or straighten first and then sister... Either way, there's a big risk of nails...
Yes, that is an option. However, it will still need to be planed to make the surface flat enough. Since the joists are insulated with sawdust, it involves quite a bit of shoveling to get the boards down and be able to screw.
Yes, when I did that exercise, I shoveled out all the shavings, added extra joists between the existing ones, and screwed/glued 28mm boards onto the existing joists. Finally, I put back new insulation. Then, of course, I had sparse paneling on it, but that doesn't matter. It would have worked just as well with floor shavings.
However, I didn't have the extra touch of sawn timber that you have - that makes it a bit trickier, I guess. Here, it was planed beams from the start, though somewhat bent...
However, I didn't have the extra touch of sawn timber that you have - that makes it a bit trickier, I guess. Here, it was planed beams from the start, though somewhat bent...
I removed (almost...) all the nails and in places where there was 15-20 mm too much, I cut off the majority with a circular saw. Held it sideways, a bit tricky because the beam was twisted. Then a plane to get it exactly level. You don't have to use a circular saw, but you mentioned it was up to 30 mm that needed to be removed in some parts, which means a lot of material has to be planed.mexitegel said:
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