Thread: Biscuits strong enough for aquarium?

Much more information required. Aquarium size, stand size, material, design, tools you have... Assuming standard kitchen cabinet type design, and a glueable surface like pine, PVA glue and a few brad nails would do the job. Not necessarily what I'd use, but they would do the job.

60cm (W) x 30cm (D) x 70cm (H)
basically a box shaped cabinet. to hold an aquarium of that dimension.

Everywhere I've looked on the internet recommends biscuits. But I don't think it looks strong at all. It's as good as just glue.

Having the wood planks standing vertical to hold the weight is fine, until it becomes wonky.
With dowels, at least it'll provide some rigidity.
But everyone I've spoken to has negative feedback on dowels, because it never aligns perfectly.

That's a worry, since I'l lneed to be joining boards.

Originally Posted by wwf9984

Is biscuits strong enough to join the structure of an aquarium stand?

If you have to ask then the answer is very likely to be "NO" when talking about the strength of biscuits.

Biscuits are great for aligning panels to make a bigger panel and if that is the role they are playing in your tank stand then fine, but do not rely on them for structural strength unless your fish can breathe air.

Cheers

DOug

you can prevent the cabinet from being "wonky" with a back nailed/glued/screwed into a rebate in the sides and top/bottom. it acts as a brace to resist the box collapsing. its the same with cheap kitchen cabinet carcasses, has a solid bottom, 2 sides, 2 rails for the top, and a back which sits in the rebate.

I wouldnt use butt jointed biscuit joins.

Depending on design parameters, i would do one of....
- splined miter joint
- dovetail joint
- butt jointed dowel joint (but i would probably cut a shallow rebate into the top and bottom of the sides so that the top/bottom has a ledge to rest on)
- finger joint

http://paul-flores.com/downloads/Joinery_Failure.pdf

Originally Posted by Master Splinter

http://paul-flores.com/downloads/Joinery_Failure.pdf

Thanks for that resource, Master Splinter - neatly filed away for later.

Some surprising results, but then I have always thought the Festool Domino was overrated.

Anyone reading it should note the caveats that the joints tested to destruction were not put through the test of time, just a destructive force, so they are not necessarily indicative of longevity of a given joint in continuous use. Still its an eye-opener on what most of us would have expected.

Cheers

Doug

The article shows framed joinery.

The cabinet I'm trying to join is like the picture.


It's currently a butt join, I feel it should be using dowels since it's stronger than biscuits.
but wary of alignment since most users have not had luck with dowels.

just measure and drill dowel holes as accurately as you can. use a brad point/nail to mark the center point of each hole before drilling to aid the drill bit finding dead center of the hole rather than wandering off as it enters the workpiece.

if you do have the dowels slightly misaligned, you can always insert the dowels into the sides OR the top/bottom and allow the glue to dry. then come back and dry fit the box and shave the dowels on one or two edges with a chisel for the perfect fit.

I'm a DIY'er
I'm trying to minimize the amount of tools i'll have to buy to join boards together and cabinet joinery.

Do you think dowels can be used for all the applications above?

joining boards together to create wide panels..the important thing is the two mating surfaces. each surface should be a mirror image of the other. the easiest way to do this is to have two perfectly straight/square edges. the DAR pine or tassie oak boards you can buy from bunnies are generally pretty nicely machined, and they might be perfectly straight. just pick up a few and put the edges together to see if there is any light gaps between the two boards. there probably will be light gaps, aim for small hairline gaps in the middle of the panel rather than gaps on the ends of the panel. gaps on the ends of the panel will probably open up over time if you have forced them together with glue and clamps. you dont need to use biscuits or dowels or dominos or machine a gluegroove or tongue n grove into the edge of the board. just a nice clean edge butt joint will suffice. when clamping the boards together, apply a little pressure with the clamps, enough to make the boards kiss each other and stop slipping sliding all over the place. then get a rubber mallet to knock the pieces into alignment with the other. then tighten the clamps up making sure to watch that the boards dont slip against each other as you increase clamping pressure.

dowels can be used to create a strong butt joint with hidden joinery for cabinet work such as joining a bottom/top to the sides.

Yes.
It's my exact sentiment to use dowels for butt joint.
But there's only Haron branded doweling jig in Melbourne. Based on the reviews, they've been horrible to work with.
Any suggestion on a fool proof system to get deal straight alignment?

Apparently these are quite good, but it'll set you back close to $200... http://www.thewoodworks.com.au/techn...dowelling-jigs

Consider alignment with dowel buttons = they look like little mushrooms with a short point in the center of the cap.
Drill one set of holes. Seat the buttons and align the wood parts, slowly & carefully, any way you can.
Then squeeze the woods so that the points make center-dents in the undrilled wood.

I find that the hardest part is to get the drill to center on the new dents for the matching holes.

In my experience biscuits can be very very strong. A lot depends on what bisquits you buy. I've been sold BIX (despite specifically saying I did NOT want those) and they were floppy and spongy, pine and the dimensioning was awful.
I use Lamello bisquits made from compressed beech and they are tremendously strong, with the odd one out with funny grain. I've actually gone off using them to align panels unless I try to glue up many boards all at once: I do a better job without them. But I use them in carcass work and for mdf drawers, even putting free standing ladder shelves together they have not let me down.