OT - Looking for design advice on horizontal hinge bifold garage doors.

Just pulled the trigger on some house extension work which will require a rather large, by UK standards, door approaching 14 ft wide by 9 ft high to fill the hole at the front of the integral garage. Upwards opening is best for various reasons. Nothing very inspiring around on the UK market. Choice of either affordable crap quality or expensive combination of decent style with apparently optimistic engineering and no attention to operation when the power is off. Being able to drive a P38 Rangie with pipe carrier on the rack into the garage appears to be an unreasonable requirement! As is 30 + year design life.

Hence I need something I can build. A weight counterbalanced horizontal hinge bifold looks fairly straightforward to make but I'm certain there are a number of devilish details which need to be got just so if the thing is to work reliably. The current door is a single leaf top hinged weight counterbalanced 9 ft x 7 ft PortalDoor, over 40 years old and looking good for at least another 20 so I know the basic layout works well and is durable but a PortalDoor won't scale up. Unfortunately the horizontal hinge bifold appears to be unheard of in the UK so I can't go and look at one for inspiration and my design skills are heavily biased to proof of concept and development work, clean sheet of paper efforts tend to be initially er "disappointing" until around Mk3. As these bifold doors seem to be common in America I'm hoping someone can give me some design pointers.

Plan A is to use 2" square or 1" x 2" rectangular steel tube for the door panel frames, monster piano hinges for the pivots and 4" square steel tube for door frame proper. Roll up straps on bobbins carried by a rotating shaft above the door look as good a way as any to do the lifting business. I guess four for the door and two at each end for the counterbalance weights would work. Power drive needed for full opening but will have to arrange an extra set of catches at 7 ft (ish) height for safe manual operation when the power is out. Seems sensible to arrange the power lift to cut in after manually opening the door several inches. Full remotes are just something else to go wrong. If the bottom tube is round it can pivot without digging into the garage floor as the door starts to open. Seems easiest to make the door close against the frame rather than into it. A stainless steel cover plate will give something for the bottom rollers to run against. If the bobbin shaft is a foot or of behind the frame the straps will pull the door back against the frame. Will this be enough to keep things in place as it moves or will a second set of rollers on a floating arm be needed running on the back of the frame?

Chain drive or toothed belt to the center of the bobbin shaft looks sensible with simple micro-switch controls triggered by door movement for up and simple push buttons for down. Will need some way of arranging for the door to relax back down onto the catches or floor when the motor stops. Slack drive and floating tensioner maybe? Electric dog clutch on the motor so door can be used when power is out. Catches are a concern as I'm pants at their design. Obviously need to be triggered out of the way by a short preliminary lift of the door so it can come down past them. Can such things be got off the shelf in the UK and where from? I presume that the door will descend under the excess weight over the counterbalance, controlled by the motor or operator, if the fully open position leaves the panels a little shy of horizontal. How much counterbalance is needed, 80 or 90 % maybe?

Alternative to monster piano hinges would be curved arms pivoting from behind. The concept I follow but not the practical design geometry. A complete new roof going on to the house so I'll have plenty of well seasoned timber out of the old roof and catslide so maybe use that. But my carpentry is strictly nail-gun level. Paslodes are fun!
Suggestions, comments and pointers to design resources gratefully received. Searching Google turns up references to aircraft hanger doors and a few videos of rather rustic devices which look way too dangerous to me.

Thanks for any help.

Clive

why not just source the higher quality american made hinges (made for a standard 2 car door-16' wide) ?

Order them online, the shipping box will be quite small.
Get the hinges, the rollers as well.

16' door is very common over here.

I suggest not 2" box tube, rather 2" (or 4") standard steel studs.
(not the 26 ga interior wall ones) the heavier duty load bearing 18 ga ones.

Small and even some large aircraft hangar, horizontal bi-fold doors are common over here, so I googled: Hanger horizontal bi-fold doors.
http://www.google.com/search?client...r+horizontal;+bi-fold+doors&ie=UTF-8&oe=UTF-8

Bob

Thanks guys

Think digger dougs idea of ordering the right hinges from USA could usefully be extended to asking for all the small stuff, hinges, rollers, catches, locks et al, as complete "known to work together" hardware pack. Home brewing panels is trivial. But who from? Actually the specific example of hinges isn't a major problem, the big piano hinges I can source over here are well up to the job, got a 6 footer with a 3/8" pin in the useful pile so easy to get more, but hinges inevitably mean at least partial exposure of the pivot to the weather. Round the corner pivoted arms put the bearings inside which is nicer when the prevailing bad weather wind is at around 45° to the panel.

Bob, thanks for the google search. Turned up some I'd not already found which was nice. But still no details on the small stuff unfortunately. Big problem with this "monkey see, monkey do" based replication of a concept is not the major engineering but the small stuff. Do A, B, C,D, E or V, W, X, Y, Z, and it all works fine. But even though A, B, X, Y, E looks as it it ought to work the practice turns out never to behave as it should more than half a dozen times on the trot!

Clive

I would NOT use piano hinge, after thinking on this more.

The industry standard hinges are offset more and more as you go up
(they are numbered), the offset is deliberate, it sets the rail at a slight angle
from true vertical.
http://www.google.com/imgres?hl=en&...ndsp=22&ved=1t:429,r:16,s:0,i:136&tx=88&ty=48

Your door is like a morse taper, as soon as it moves up, it moves IN, to reduce drag
on the weatherstripping. The hinges are made this way for a reason. The system fit's
together, rails, hinges, wheels.

If someone here (in the usa) where to buy these for you (kit them together along with
all the other hardware) and remove them from their packaging, they would be sold
to you as "used", would this negate import taxation ?

With a roll your own hanger style door it is important to not allow it to open fully as this will cause collapse with out complicated counter weighting.

Tends to make the design take up alot of overhead space.

Heavey Metal said:

With a roll your own hanger style door it is important to not allow it to open fully as this will cause collapse with out complicated counter weighting.

Tends to make the design take up alot of overhead space.

Click to expand...

Yup, the hangar I was in had a comemrical bifold door, used up about 4' overhead,
put allot of torque to the face framing (actually most all bi-folds use seprate I-beam columns
separate from the building)

And if the cable snapped, it became a guilotine.

Again, 14' wide is not a problem with standard residential door panels over here, I don't see any special
differences in your design requirements.

Maybe a higher wind loading ?
http://www.wayne-dalton.com/residential/Documents/windload/Windload-Option-Code-Index-Model-9600.pdf

Also wind loading on the opened door.

Heavey Metal said:

Also wind loading on the opened door.

Click to expand...

Yup, the residential type door tucks inside, no wind loading (or very much at all).

One thing the bi-fold people like to hype is the 4' overhang when up, provides
a "shelter".....until the roof snow slides off onto it (like it does every spring around here)

digger doug said:

One thing the bi-fold people like to hype is the 4' overhang when up, provides
a "shelter".....until the roof snow slides off onto it (like it does every spring around here)

Click to expand...

Heh, heh. That sort of thing I know about as the existing outward opening panel provides a 7 ft x 8 ft overhang shelter. Great when working in UK standard rain. Drowned Rattus effect if you forget and stand in front when pulling down to close it afterwards!

Thanks for the homework links to the proper type of hinges. Study time methinks. My door has to be outward opening for various reasons so piano hinge geometry is workable although significantly less than ideal. For importing its actually easier in makers packages rather than opened "used". UK Customs default setting is obstructive!

Heavey Metal makes good points about collapse potential and outward pull loads. I'm figuring that something around 10 to 15° included angle between the two open panels at the high setting will be safe at the cost of a foot to 18" of maximum headroom. Which will still leave plenty. The door will run pretty much from sidewall to sidewall so tension strutting the top of the side pillars back to the main wall will be very easy. The house modifications include extending the front room bay window wall line across the whole front of the house so the garage door will be around 18" in front of the upper wall. Socking great RSJ beam going in over the garage opening to support that wall so can tie back to that too if need be. Said RSJ makes inward opening much harder tho'.

Multiple redundancy with several lift cables and two weights looks the best way to avoid the guilotine effect although I'll probably repurpose an inertial reel seatbelt spool or two as a last ditch safety device or even buy the proper drop safety thing. That said my existing door is a single cable set-up and it was always obvious when a cable change was due long before things got dangerous.

Thanks.

Clive

A few years ago SWIMBO wanted storage on the patio, under the roof eaves, with doors. Being on a walkway and not wanting to block it, no room for swing, sliding or lifting doors, so I sketched a way to horizontally bifold a full covering for the opening, with her "beach shack" less than 3' away. Not visable but noted in the sketch, two 1/2" thick plates of steel in covered slots behind the shelves for counterbalance. There is a cam follower at each of the lower corners of the bottom panel with strips of steel strapping, (HVAC) as "tracks", stuck with flooring adhesive to the wood framing.

While sketching the geometry, (builder understands the draftsman) I got carried away, (commom for me) and wondered on paper how this could be scaled up for a future shop out back, where there would be no shelving in the way, 5th attachment below.

In practice for this big door, I'd chain drive a common shaft between winch drums on both sides of the door, to avoid the twist of the small door, visible in the 3rd pic above, where the two counterbalances are independent of each other.

Bob

Thanks for the pictures Bob. Look good. More for me to think about. I have a feeling that your balanced door design, or at least something rather similar, is available commercially as something with the same folded endpoint turned up in my Google searches for info.

Clive

Hi Bob,

I really like your desing. I´ve been wanting to use bi-fold doors on a small project I have and came across your post.

You wouldn´t happen to have more pictures?

One of the things I was wondering abot was where you position the wheels at the bottom so there isn´t a gap on the sides of the door, which I see you don´t have.

Are the doors stiff enaugh with the plywood and outer frame?

Thanks for the post and pictures,

Cheers,
Sigurbjorn

I've been worried/wondered about Bob. Truly wonderful person. But he has not posted for years (that I've seen). OP was 2013.

smt

In this link is a set of bifold doors I am building. http://www.garagejournal.com/forum/showthread.php?t=335958&page=2
I just used 6 hurking regular door hinges I got off eBay. There is a video link. Still to do is attach rollers so the doors don't bounce at start or stop and skin and insulate them. That will get done "if" the fricken snow ever goes away. My doors open within their framing(12'tall) causing me to loose 18" in height. That's ok as my tractor is 9 1/2'tall. To keep the full height of the opening many will hinge the top of the door in front of the frame and above the frame. Look up schweiss doors for examples.