Steel framed doors

[MetalMonkey]

I have a project coming up and need to build some steel framed garage doors which will be clad and insulated. Each door needs to span ~ 2.4m (i.e 4.8m total) and I may opt to go with four bi-fold 1.2 segments instead. They will be hinged either side of the 4.8m opening from a Universal steel column (RSJ).

Currently my plan is to build a framework out of angle, probably 40x40 or 50x50 to give some space for insulation, with a diagonal cross brace and then weld on barrel hinges once everything is trued up.

I’m a little concerned with the amount of potential sag across this span – has anybody done anything similar and can comment on the suitability and thickness of angle for this, or any other suggestions or consideration?

I want to make them strong enough, but not so heavy they disappear through the earth’s crust.

 

[frank horton]

yeah, dont use angle.....always go for box.....
made a gate for somebody 2.5m x 2.5m and u could wobble bend top to bott at the diagonal..50x50mm angle.....he wouldn't listen.....
then remade it in50x50x3 box and he was quite happy but at his expence......

bi-fold's are ok if u have no room but they are inherrantly weak cos of the extra hinges.....security wise.....
plus u need tomake room in the design for adjustment......
for ease of use I always prefered a rolling door on a track.....also not entirely secure but easy enough to secure tho with a bit of extra thought.....
u need to say if this is also the ONLY door....pedestrian door...?????

for my new workshop there will be 2 rolling doors....7mWx6mH....obviously using heavier section....

as for sag..personally I'd be using 100x50x3 across the bottom..u didn't say anything about height but at a min 3 hinges per door if u go with hinges....
but I'd be using 4......
hope this helps a bit.....

 

[MetalMonkey]

Thanks for the reply. The reason for the angle was mainly because it provided an easy flange for the cladding, but flex was another concern.
I was hoping the cross bracing would help with this and I was worried adding too much weight would create issues with sag, but it sounds like box is going to be better.

Doors are around 2.2m high.

If I go the bi-fold route the plan would be to put shoot bolts on three of the leafs leaving just one that locks on a latch for access.
Although there will be a separate internal access door into the building, they do want to be able to access it via one of these external doors as well.

If it is a track door it would have to be a bi-fold as there isn't room either side for a rolling barn/hanger style and the full opening needs to be used so you can't roll one side over 'tother.
The ground slopes up from the entrance, so a full 2.4 width might be an issue for clearance, and also a bugger if the wind catches it, which is why i was leaning towards four 1.2 segments - also a bit more manageable for fitting.

I was looking at 4x 100mm hinges per door.

What section would you use for the upright, 50x50?

 

[Keith 66]

I have just finished a similar job on my own garage, the original up & over door was broken & was a pain to use, plus i couldnt put stuff in the roof cos the door hit it.
Decided on a pair of doors, As i had a pile of 30mm square box & a pile of 30mm angle thats what i used. Two door frames of box section with two horizontal bars across each equally spaced 600mm apart. Angle iron welded on inner edges to give a ledge for the panels to go in.
They didnt need diagonals as they were so stiff anyway. I was given six sheets of 1.5mm galvanised steel sheet & only had to trim a bit off one end for a perfect fit. These went in the apertures & were backed by 12mm shuttering ply, whole lot bolted on with 5mm socket head bolts.
Took me a week to make them & me & my son hung them yesterday, they fitted perfectly!
The Door pillars & lintels were made from 60x40 box as i already had it! Picked up on existing bolt holes in the precast panels (Dont even think about trying to drill new ones!,
Heres a few pics,