Re: ripping 2x8s in half for hive bodies
Re-sawing the 2x lumber (1.5" thick actual)...which is what you are doing...is best done with a band saw for minimal kerf and it also tends to be safer than using a table saw. Construction lumber can tend to move while cutting it down the middle due to moisture imbalances and because today's lumber comes from younger, fast growing trees. The band saw will deal with this better than the table saw will and having the table saw blade raised to max requires great care to avoid accidents.
It's pretty much impossible to get two boards that are a full 3/4" thick from a 1.5" thick piece of lumber, regardless of the saw you use, because of the saw kerf that you note. That's not a horrible thing as long as you adjust for that variation in thickness when you build your boxes and consider they will be a hair less sturdy than full 3/4" thick stock. If you check for local sawyers, you may be able to get both 4/4 and 8/4 rough cut pine or fir pretty inexpensively and it mills out nicely for hive component construction. I pay well under a buck a board foot for 4/4 rough pine. Knots are not an issue if they are stable and by using less expensive rough lumber to start, you can waste a little insuring no knots are in the areas that will be joined to make the boxes. Pine or fir is typical for bee boxes because it's not heavy and is relatively inexpensive. In some geographies, cedar or cypress come into play because they are plentiful and equally inexpensive.
A box joint jig/sled is easy to make for use on the table saw. It could also be made to use on a router table or shaper, but that's uncommon for nominal 3/4" box joints due to the size of the cut. A dado blade on a table saw cuts these bigger joints better. Alternatively...and there's already a substantial discussion in this forum area going on the subject...rabbit joints can be used for hive boxes. (I use rabbit joints for the small number of boxes I build) Glue (I use Titebond III) and pneumatic staples or 15 gage coated finish nails will hold nicely regardless of the joinery you choose.
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