Which joint?

[Dave876]

Hi all,

I need to make a number of boxes to hold tilley lamps for the Scout group. It's going to be rough and ready and liable to be mis-treated, as well as getting damp, muddy etc. so I was just going to use some ply, probably 9mm.

I have an idea for the design - essentially a long tall box with a hinged front door - but I am now too sure on the joints to use to put it all together. I could just have it all butted up with glue and nails, but this has zero mechanical strength and I know the boxes will be abused. Once I have the sides done, what about the top and bottom?

So what joints would people use and why? More the why - I can then make a more informed decision for any future projects!

Ta muchly,
David.

 

[Gary S]

Hi David,

Someone much more experienced than me will probably be along shortly, but for me 9mm Ply would be a tad too flimsy for the sort of thing you're talking about. I'd rather go for 18mm exterior grade plywood - it could then take being chucked around and left out in puddles.

In terms of joints I'd be inclined to go for a rebate of about 9mm at the end of one side with the other piece of ply 'butting' into it - plenty of surface to glue and you can screw it to increase strength further. For this you'd need a router and a straight cutting bit (might be teaching you to suck eggs here - apologies if that's the case).

Hope that helps (up until the point where someone else more experienced comes along and gives you entirely different advice!!).

Cheers

Gary

 

[StevieB]

I would go for a finger joint to be honest. 12mm might be better than 9mm, but to be fair a tilly lamp is a fairly fragile piece of equipment so should be chucked around too much!

Rather than a front door, the ones we used to have were simply a drop in from the top type box. The bottom section was deep enough to hold the entire lamp and the top half was the same width and depth but shorter with a hinged flap and a bolt to hold it inside so that spare mantles and seals could be stored with the lamp. The two halves were joined with standard clips to hold the top and bottom together. Painted red if that helps!

Steve.

 

[Scrit]

I'd go for 12mm, too, but with loose splined mitred joints and a good exterior grade RF glue (e.g. Extramite/Cascamite). For additional strength hardwood glue blocks or rather "glue strips" could be added down the insides of the corners. If speed and simplicity are the goal then butt joints strengthened with a glued loose tongue woulds work, although the durability wouldn't be as good. Alternatively making a 6- or 8-sided box might yield strength benefits from the shape, although it would be more difficult to cut and join accurately.

Scrit

 

[Dave876]

Hi Steve,

Ok - I might go for something a bit thicker than 9mm then! And yes - you are right - they shouldn't get thrown around too much, but there is a limit on the number of times you can shout the same thing in a day....

Finger joints would work - I was tempted with dovetails, having just bought a jig - do you not think they would be better than fingers?

Interesting idea for the top loading box. I had thought about that but I figure that when they take the top off, they might just pull off the top cover and risk breaking the mantle. I had factored in a shelf for the burner and spares, but I must admit I couldn't see how that could work with a top loader unless you had a false bottom.

One further idea I have had - once the smaller boxes are made, make one bigger box to hold say 2 tilleys, plus some camping gaz lights (minus the big gas bottles), plus the parafin. This would be in something thicker - maybe 18mm. With that in mind I would ideally like the boxes to be 'smooth' with no sticking out hinges, handles or clasps.

I'll consider the 'painted red' part, though to be fair most of ours are gold and rusty!

Cheers,
David.

 

[dickm]

I've got an old Avometer which is housed in a wooden box with a <sliding> lid, running in reinforced grooves on the long sides. I guess you could do something similar to give a smooth outline? Not sure you would need much more than 10mm ply, would you, but I'd strongly recomment wooden fillets in each corner.
Just a last worrying thought - will your users remember not to put the lamps away hot?????

 

[DomValente]

Didn't have a scout troop in Central London where I was brung up, just spivs, so I'm not sure if these have to be pretty.
If not I'd use 12 or 15 mm, butt, glue and screw, the sliding lid's a good idea, or piano hinge with a hook and eye lock.

Dom

 

[Dave876]

Hi,

Thanks for the general feedback.

Scrit - I agree with some strips down the inside for extra strength, and thanks for the tip on the type of glue. But why hardwood? Would it be that much stronger than some strips of pine?

And thanks for the thought on the sliding front door. I was going to have something hinged and held in with magnetic catch. Although I have plenty of boxes with sliding doors, for some reason it just didn't occur to me!


David.

 

[Wanlock Dod]

but there is a limit on the number of times you can shout the same thing in a day....

Yep, I know that feeling...

 

[Shultzy]

This might be an ideal use of scrap pallets. I would certainly glue and screw for extra strength. A panel sliding down from the top would stop internal items from falling out. I would be inclined to have an internal strap/fixing to stop the lamp from banging about when carried.