Suggestions for what size PT lumber would be needed to safely (think overkill) support a 300 gal (96x30x24) acrylic tank. There will be a 66 inch span along front and back of tank. I was thinking doubled 2x6's (gorilla glued and lag bolted) for perimeter and single 2x6 cross bracing, but could be convinced 2x8 is needed. Lumber frame will be j bolted to filled, rebarred block and 3/4 PT ply under the tank. I want to leave space for access to a big sump under. Tank will be outdoors in a public area and could get bumped hard.
What Size Lumber for Stand - 66" Span
- Thread starter farawayinn
- Start date
PT 4x4s are what hold decks up. using those as corner posts and then ribbing with 2x4s every 6 to 12 inches would be OVERKILL!!!!! or you can just make posts by nailing together 2x4 pieces. you will get more support from evenly spaced "ribs" of 2x4 than one crossbeam.
thanks for the info swede. we can't use lumber for the base due to occasional flooding in the area.
block walls at both ends, leaves space for access to the 170gal sump and feeder tank underneath. does anyone know where would i find a table for lumber deflection, specifically pressure treated lumber.
block walls at both ends, leaves space for access to the 170gal sump and feeder tank underneath. does anyone know where would i find a table for lumber deflection, specifically pressure treated lumber.
hi again swede. i guess what i'm looking for is a table that shows how much the wood will bend (deflect) under a specific amount of weight.
i've found span tables for floor joists and beams and also roof rafters, but they are based on spacing of the beams. the beam tables that i found are based on the spacing of the joists that will go above. very useful stuff if i want to build a house, not so useful for my little stand build. also, none of the tables i found had any info on pt lumber.
i've found span tables for floor joists and beams and also roof rafters, but they are based on spacing of the beams. the beam tables that i found are based on the spacing of the joists that will go above. very useful stuff if i want to build a house, not so useful for my little stand build. also, none of the tables i found had any info on pt lumber.
do you know how to crown wood? crowning wood will help the lumber support the weight it is bearing. All crowning is is looking down the piece as you lay it on its side and sight down the wood to see which way the wood curves. you will see that one side of the piece curves naturally. this is the side that will face up so that the weight pushes down on the crown. doing this will help the lumber maintain its strength over time. any floor worth anything has its joists facing crown up to be sure to bear the load. as for deflection of the lumber, you don't need to worry about it as much. your better off going overkill. using 2x6 and spacing them out 8 inches apart will give you more than enough support. and one 2x6 will get you about 4 pieces that you can use for this (assuming your tank will be 24" or less wide)
yea just grab some iron and MIG and TIG it up! you could speak with a blacksmith and they would custom build you an iron frame.
Over all I think you'll trying to over think this... since your building with block I would personally build a floor on top of your blocks (typical joist framing like in a house) with some 2 X 6 just to make sure that it's got no spring in it at all... then sheath with 3/4" ply and consider it a done deal...