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SirBB
02-26-2017, 11:48 PM
I'm going to install front Shoulder Seat belts in a 1960 Hard Top, has anyone done this and have any information how it was done.

Joe Johnston
02-27-2017, 07:47 AM
There is a lot of info on some of the Mustang forums. Procedure will be similar. Please be aware of the possibility of spinal compression as often add on shoulder belts are mounted far to low.

simplyconnected
02-27-2017, 12:03 PM
There is a lot of info on some of the Mustang forums. Procedure will be similar. Please be aware of the possibility of spinal compression as often add on shoulder belts are mounted far to low.It depends on the seat.

My Mustang convertible had a plastic belt loop on the back of the seats. The belt retract was in the rear sidelite box, below the top of the seat. It had to be because again, this is a convertible with low door pillars. - Dave

sidewalkman
02-27-2017, 04:23 PM
It's up to you, but I can't see a way to install a shoulder belt that wouldn't both wreck your back in a rearender or facilitate having to drill holes in your headliner.

The stock buckets are too low for a mount on the corner of the seat, so you would have to route them above that, and since we have a hardtop there is no B pillar so now we're looking at the headliner.

Joe Johnston
02-27-2017, 05:34 PM
As mentioned, do some Googling and read about spinal compression, then decide.

dad's58
02-27-2017, 10:47 PM
I have a 58 Bird and installed front and rear shoulder harness with help from Juliano's and a guy in Australia, where front harness are required in 1960 and up cars. They require the install to be approved by an engineer . I have photos but need to dig them out and try to post, or private message me with email address.

YellowRose
02-27-2017, 11:37 PM
David, if you have those pix, please do post them. As a Paid Member you can do so right here on the Forum. If you have any problems, call me and I can talk you through it. Or you can send them to me and I can post them for you. If you post them, make sure they are no larger than 800x600pixels. We might be able to put something together on how to do a shoulder strap installation properly. Especially since it appears that an engineer was involved in this to obtain proper clearance from an inspector...

simplyconnected
02-28-2017, 08:33 AM
This is Rob Miller's 2005 Retro Bird. What do you see?

http://www.squarebirds.org/vbulletin/attachment.php?attachmentid=13716&stc=1&d=1488248333

Joe Johnston
02-28-2017, 10:34 AM
Expounding on what Simplyconnected and Sidewalkman posted below:

The top loop securing the shoulder belt at the top of the seat back (like pictured on this 2005) was something I extensively explored many years ago with my 56. This could easily be done as the seat back panels are removable, steel extended up to secure a holder of some sort.

The next issue was to make the seat back lock into position and not flip forward. I'm sure that would be possible too, but thought I would engineer that later. A mount for the belt at the floor would not be a problem.

The info I was finding all related to the distance of this retainer to the center of a persons ear. To be effective in holding a person back and not induce downward pressure the upper loop should be above the shoulder approximately at ear level for someone of average height.

I am 5' 11" and in my daily drivers this retainer is mounted on the "B" pillar at or just above the center of my ear. I would suspect the 2005 pictured has high seat backs placing this retainer near the driver's ear level.

On the 57 my ear is 10" above the seat back and 9" above on the 63. A loop mounted and looking like the 2005 on these old and low seat backs will induce downward pressure. I do not own a Squarebird but would guess the measurements to be similar for someone my height. It would be interesting to have an owner of a Retro bird sit in the seat and measure the vertical distance from the center of their ear to the loop.

I have also seen the shoulder belts added with retainers bolted through the roof, with a chrome cap visible on the outside. Effective, but not attractive and I would wonder if the bolt would tear out of the roof skin in an accident?

I am proof shoulder belts work and believe in them. I had a new Yukon for 3 weeks when a Grand Marquis pulled out in front of me. I hit him at about 45mph, totaled the Merc and I never hit the airbag! (Yukon had about $11,000 in damage) The shoulder belt stopped me and I was very slightly sprained but unhurt. I'm all for this modification, but more thought needs to be put in the project before just bolting something in.

Hope Dad's58 supplies us with pictures.

simplyconnected
02-28-2017, 11:35 AM
Joe, I'm not disputing your hard work but...
I'm 6'4" and my head nearly touches the head liner of nearly every modern car I sit in, so I recline slightly. Now, I realize most folks aren't that tall but, I have to raise my headrests or they center on my neck.

My Mustang Convertible had a back seat so my front seats folded forward. With the window open, my arm felt comfortable 'hanging out' over the belt molding. The seat belts never came close to my ear.

I used to own a Tempo for getting groceries. That car had a retractable shoulder harness. The roof had a track where the shoulder belt attached. Close the door and the shoulder belt traversed rearward, then stopped via an electric motor. Open the door and it went all the way forward. (Don't open the door and hang your head out to back up or the shoulder belt would pull it back around your neck.) The track was not attached to the roof skin and neither would any shoulder belt. That's why all support attaches to structural inner-panels, not outer skins. - Dave

Joe Johnston
02-28-2017, 11:52 AM
Absolutely agree and is why I thought the bolt through the roof system inadequate. A lot of structural engineering goes on to safely stop a body nearly instantly in a collision, holding it back and not forcing it down. Properly installed and worn, the seat/shoulder belts work. I always thought the power rail set up Ford had worked well, took a bit to get used to though for me.

When working I had access to a lot of engineering data (nearly anything I would ask for) and the issue of spinal compression was a major concern. Granted the magnitude of the liability is tremendous for a manufacturer and would not extend to the modification of an old car, but the info was available.

The simple seat and shoulder belts do work.

For the record I have not added shoulder belts to either of my Thunderbirds.

Yadkin
02-28-2017, 07:31 PM
I'm going to install front Shoulder Seat belts in a 1960 Hard Top, has anyone done this and have any information how it was done.

Here's how I did my '64. Yours may be similar.

http://www.squarebirds.org/vbulletin/showpost.php?p=106846&postcount=9

Joe Johnston
03-01-2017, 08:50 AM
Nice job! Shows it can be done well and also look good.

sidewalkman
03-02-2017, 11:35 AM
Here's how I did my '64. Yours may be similar.

http://www.squarebirds.org/vbulletin/showpost.php?p=106846&postcount=9

That would work, I would imagine there is some engineering happening behind the C pillar but effective.

Yadkin
03-02-2017, 02:59 PM
That would work, I would imagine there is some engineering happening behind the C pillar but effective.

The only engineering is to come up with something equivalent to the factory connection. My body man, who did the welding for me where I told him to place it, was concerned that this location wasn't strong enough. But the factory metal here is the same gauge as where the floor points are, and his length of weld was much more than the factory.

sidewalkman
03-02-2017, 04:08 PM
The only engineering is to come up with something equivalent to the factory connection. My body man, who did the welding for me where I told him to place it, was concerned that this location wasn't strong enough. But the factory metal here is the same gauge as where the floor points are, and his length of weld was much more than the factory.

After the welding I imagine some repainting was in order?

simplyconnected
03-02-2017, 05:22 PM
...But the factory metal here is the same gauge as where the floor points are, and his length of weld was much more than the factory.That's why we always back up the location with heavier steel.

In the case of a floor pan, it's a heavy square, usually 1/4" thick with an extruded 1/2" hole (or a 1/2" Nylok nut).

In the case of a door pillar or roof rail, it's also a heavy strip of steel.

Both additions of steel are either MIG welded, projection welded or button welded in place. The idea is to spread the tension over a large area.

Yadkin
03-02-2017, 09:49 PM
After the welding I imagine some repainting was in order?
I did this work before paint, but the weld area is not on exterior metal. A careful welder should have no problem keeping the surrounding area cool enough not to damage paint.

Yadkin
03-02-2017, 09:51 PM
That's why we always back up the location with heavier steel.

In the case of a floor pan, it's a heavy square, usually 1/4" thick with an extruded 1/2" hole (or a 1/2" Nylok nut).

In the case of a door pillar or roof rail, it's also a heavy strip of steel.

Both additions of steel are either MIG welded, projection welded or button welded in place. The idea is to spread the tension over a large area.

As I recall the factory reinforced area is oblong, no sharp edges that would tend to tear the substrate.

YellowRose
03-06-2017, 11:40 AM
I am in contact with David, Jeremy, and Darryl Heiner in Australia. Darryl did the shoulder harness seat belt installation on Jerermy's '60 430MEL Black Raven that used to belong to Bart Como! He still has it. I am working on putting together a Tech Tip on how to install retractable rear seat belts like David did in his '58 AND the Shoulder Harness set up that Darryl does for the guys Down Under. Unfortunately, when Darryl changed companies, he lost his pix. He has given me some additional information though. I am trying to piece together a step-by-step Tech Tip to help those who want to install front seat Shoulder Harnesses in their Squarebirds.

David has suggested this. If someone has a Squarebird with the headliner removed, please take some photos of the C section where the harness would go. We need to see what that section looks like because that is where the top of Shoulder Harness attaches to. We think that area is built up, but, unfortunately, neither Dave, Jeremy or Darryl have pix of that area. BUT I DO! One Pic and I will post it below. In the pic below you will see, from Davids '58, where that top of the Shoulder Harness attaches to the C Column. When Darrly does these installs, (and he has done many of them Down Under) with the headliner out, he welds in a plate in that area to strengthen the anchoring of that harness. When the interior is intact, and to prevent fire, he lifts up the headliner in that area and uses self tapping screws in the mounting plate on each side, then covers it up with the headline. Here also is a picture of the metal plates he uses and I will give you the dimensions in the Tech Tip.