Thread: Shed door

Hi there!
I am building a new shed. Almost finished rendering the walls, will get the wiring done next week and so I will be able to start working on the doors. Two hinged doors, 1.5 meter wide each. No I can not have a rolling door, have an I beam right over the opening.
I am thinking 50x50 square tubing lined with 10mm bracing play each side. Yes, on the heavy side and this is what brings me to starting this thread.

The hinges for this two doors will be welded to the two 100x100x5mm post that are on each side of the opening. My question:
What wall thickness do I have to use for the square tubing for the door, particularly the one that will take the hinges. Is there any way to guesstimate this? I was thinking 3mm for the frame edge that will take the hinge and 2 mm for the rest to save on weight.
I have yet to find appropriate hinges. If not may have to make them. Any suggestion for good hinges?

All ideas welcome!
Marc

Hi Marc, for the hinges look in Bunnings or similar for heavy duty hinges, they will have a ball bearing ball in the tube that is lubricated by an oil hole on the side near the top. The shaft is about 14mm welded onto a bit of 5mm plate, the top is a piece of round bar that has been drilled about 14.5mm. depending on the brand some are marked TUFF Hinges.
Kryn

A pair of the weld on butt hinges would be suitable for your application.

Hinges - Goliath

Thanks DJ, they are the ones I was referring to.
Kryn

I have seen the hinges from Zenith similar to the one in your link. They seem very strong but if you look closer, the pin side is welded to a 2.5mm plate by just 20mm or so. Not good. Perhaps the Goliat are better.

Any suggestions for the wall thickness of the square tubing?

Hi Mark, I think you will find that the 2.5 welded on the side is just a packer to allow for the top section. When welded in place it would be welded on both sides anyway, so I wouldn't be to worried about it.
Kryn

Originally Posted by KBs PensNmore

Hi Mark, I think you will find that the 2.5 welded on the side is just a packer to allow for the top section. When welded in place it would be welded on both sides anyway, so I wouldn't be to worried about it.
Kryn

Hum ... not sure what you mean.
This type of hinges some call prison hinges, consist of two parts. The top part is a tube welded to a plate with or without holes for screws. The plate is the flat part of the hinge and is welded all along the tube.
The bottom part of the hinge is the pin that is also welded to a plate that makes the other half of the hinge. The one I have seen in the hardware store, have a pin that is too short so the plate is nice and big but has a cut rebate to match the short pin and ends up having a very short weld to the pin.
A poor design if you ask me. I have yet to see the goliath one. Unfortunately their web site overlaps the price list over the close up picture of the hinge making it impossible to see.

As far as the door itself, I am now thinking that perhaps I can make the two vertical edges in 50x50x3 and the horizontal and diagonal members in 50x25x3 or perhaps 60x30x3. This way the 10mm plywood will fit flush to the two sides leaving the square tube exposed. I can reuter a few vertical V grooves to make it look a bit better.
I still don't know if I need to go 3mm thick or is it overkill?

G121 LH - Goliath

OK This is a better design than the Zenith. The pin in the lower section is actually inside a tube and not welded directly to the plate. Also see that both weld, the top and the bottom one are both 50 mm long.

Originally Posted by Marc

As far as the door itself, I am now thinking that perhaps I can make the two vertical edges in 50x50x3 and the horizontal and diagonal members in 50x25x3 or perhaps 60x30x3. This way the 10mm plywood will fit flush to the two sides leaving the square tube exposed. I can reuter a few vertical V grooves to make it look a bit better.
I still don't know if I need to go 3mm thick or is it overkill?

You've said the door will be 1.5m wide, but haven't said how tall. That would provide some indication of the mass involved.

I can't see any benefit in making the outer vertical any heavier than the lightest section, as most of the stress will be on the hinged vertical. I assume you'll have a single diagonal from the bottom of the hinged side to the top of the outer side? The only downside with using a thinner profile for this and the horizontals is reduced stiffness, but as it's only 1.5m wide, that probably won't matter.

As for insetting the plywood cladding, as it's only 10mm ply, I assume you'll need to attach a flange along the verticals to fix the vertical edges of the ply to. One alternative might be to make an inner frame out of 50x25x2 (including verticals) with additional 50x25x2 outer verticals rotated 90 degrees to give you a 50mm door thickness (maybe use 3mm section for the hinge side). Stitched every foot or so, this would make your verticals a total profile of 75mm - much stronger than a single 50mm profile, and would make attaching the ply simpler.

Originally Posted by RustyArc

You've said the door will be 1.5m wide, but haven't said how tall. That would provide some indication of the mass involved.

I can't see any benefit in making the outer vertical any heavier than the lightest section, as most of the stress will be on the hinged vertical. I assume you'll have a single diagonal from the bottom of the hinged side to the top of the outer side? The only downside with using a thinner profile for this and the horizontals is reduced stiffness, but as it's only 1.5m wide, that probably won't matter.

As for insetting the plywood cladding, as it's only 10mm ply, I assume you'll need to attach a flange along the verticals to fix the vertical edges of the ply to. One alternative might be to make an inner frame out of 50x25x2 (including verticals) with additional 50x25x2 outer verticals rotated 90 degrees to give you a 50mm door thickness (maybe use 3mm section for the hinge side). Stitched every foot or so, this would make your verticals a total profile of 75mm - much stronger than a single 50mm profile, and would make attaching the ply simpler.

Yes, that sounds like a sensible idea.
The doors are only 2.1 High. I thought that using flatter tube for the inner frame would make it a bit wobbly that is why I thought to go 3mm for all, and perhaps 60x30x3 in stead of 50x25 ... however wouldn't the ply screwed to the metal frame give it some stiffness? 10mm bracing ply both sides is a lot of wood. I suppose I can go 12mm, it would still fit flush
I thought of adding a vertical 25x25 to each vertical 50x50 to screw the play to, but yours is also a practical idea.
As far as diagonal I thought I need two or three parallel diagonals to give the play some support. I suppose the diagonals can be 2mm thick or this door will end up weighting 100 kilo each

Originally Posted by Marc

I thought of adding a vertical 25x25 to each vertical 50x50 to screw the play to, but yours is also a practical idea.

Given it's only 2.1m high, you could probably go with a 50x25 outer (top and sides) with 25x25 inside, giving you an effective 50x50 overall profile, and something to fix the ply to all round. I believe a single 50x25 diagonal will do the job and keep the 10mm ply reasonably flat, as I assume you're not adding insulation? You'd probably need to add a horizontal 50x25 at the join in the two ply sheets (unless you can get 1400 wide ply) and you could choose to run the 50x25 flat with 25x25 top and bottom if the frame seemed too floppy.

My back gates are 1.5M wide each, and 2.0M high, and covered in 20mm thick Cypress pickets (this should give you an idea of the weight). The frames for these gates I made from 25x25x3.0 Duragal, and they have not sagged or dropped in 8 years. They have those ball bearing hinges (I think mine are an older style with the pin and tubes both welded to the flat), but the general guide that an inch of weld holds a Tonne, this design is more than enough.

The frames are a perimeter rectangle, with a centre cross-brace, and two diagonal braces, each one from top/bottom hinge point to outer centre point.

If you're fitting plywood to the frames, you wouldn't need to add diagonal bracing as the plywood would do the same job.

Another thought... You could have the hinged vertical in 50x50, then the rest of the frame in 40x40 and attach the 10mm ply directly onto the 40mm frame, leaving the 50mm exposed...

Originally Posted by Yonnee

...Another thought... You could have the hinged vertical in 50x50, then the rest of the frame in 40x40 and attach the 10mm ply directly onto the 40mm frame, leaving the 50mm exposed...

That is what we have been elaborating with RustyArc.

My last back of the envelop design (as per our fearless leader), is like this:
Verticals 2 at 50x50x3
Horizontals 3 at 50x25x3
Diagonals 2 in each rectangle in the obvious position 25x25x2
Extra packing 25x25x2 against the verticals to allow for fixing the ply
Still uncertain if I want an extra 50x25 sideways top and bottom to finish off the frame. Yes I realize that with the 12mm ply each side it will be sort of bulletproof....I love bulletproof. Mmm I could use Kevlar in stead of Styrofoam ...

Anyone venture a guess at it's weight?
That is why I am thinking I need a good hinge ...

More to the point.
What is the best way to brace this construction to end up with a nice flat door and not a distorted mess?
Would clamping 50x50 diagonally on each side in opposite direction forming an X be enough or do I have to tack weld something more substantial?

A flat floor, square cuts, and tack all the joints first - at least 2 per joint to start with, and once square, tack all the rest of the corners of each joint.

Tack, check and tack again, then once all is done, weld diagonally.