The Ford Barn

goldie · 04-06-2023, 04:45 PM

There is just so much that can be done to make a Model A safer. My main concern is not to be thrown out of the car. In the case of my woody, a rollover would result in a massive pile of wood shards that may impale me, compression fracture the last of my concerns. I drive a 1970 Jaguar E that sits very low, most modern car bumpers are at my eye level, and there is a greater chance of my demise in the Jag at speed than my puttering around in the A. Driving defensively helps the odds I hope. Enjoy while you can.

Ed in Maine · 04-07-2023, 03:23 PM

There is a lot of good comments here. I have lap belts in my Victoria which go to the frame. I know that any serious accident in my Model A will result in me owning the farm! All I can say is that I drive very carefully and do not drive any faster than I have to, to meet traffic conditions. I have had 59 years of motoring in Model As and I have enjoyed every moment of them. I am hoping for another ten years before I have to give it all up. One thing I do like about my seat belts is that they keep me securely seated behind the wheel. There is none of that sliding around. My biggest fear is that door popping open on a turn and falling out. Ed

ModelA29 · 04-07-2023, 04:52 PM

Many moons ago I did an article in Kit Car magazine on the lack of seatbelts in kit cars. I relied heavily on papers by the SAE (Society of Automotive Engineers). I looked at their site and they now charge for access to the papers but they may be available at a local library. Take a look at the testing limits and you'll see some of the problems you'll encounter putting in a strong enough anchor point.

DYNAMIC TESTING OF SEAT BELTS 570045

TESTS simulating actual dynamic loading that a seat belt might receive during a crash of a motor vehicle are discussed in this paper. Design criterion was set as 20-g deceleration uniformly applied for 50 millisec.
150 pound driver @ 20g = 3,000 pounds in a sharp yank not a slow pull

Biomechanics of Seat Belt Design 720972

This paper discusses the development of adequate criteria and evaluation methods for seat belt restraint design. These criteria should include the effect of seat belts in abdominal injury as well as head injury. It is concluded that belt load limiters and energy-absorbing devices should limit head-to-vehicle contact, ensure that the lap belt maintains proper contact with the bony pelvic girdle, and limit the belt loads. Studies are made of pulse shape and belt fabrics.

Synchro909 · 04-07-2023, 08:58 PM

IMO, even if a seat belt pulls its mounts, it has still done some good. I'd still wear it than be totally unrestrained.
As for the body detaching from he chassis in a collision, I don't believe it. We have all seen lots of photos from the day of crashed cars, some quite seriously crashed. I haven't seen a one of them where the body detached. I regard that as an unsubstantiated old wives tale.
I have installed 3 point belts in both my Phaeton and my Tudor using the same method. There is no attachment point near my shoulder. I had made, a "Y" shaped belt that attaches to the strong box section at the very rear of the body, comes forward and forks just behind me with one arm of the Y going over each shoulder. The belt includes a lap belt component and when it is done up, it is like a racing harness. I thought about how to install a 3 point belt in the Phaeton for a while and came up with that. I liked it so much, I also used it in the Tudor. My CCPU and the farm Ute have lap/sash belts in them. The Ute ones are the modern recoil type.
I reckon it's all a game of playing the odds in a crash. I want to swing them in my favour as much as I can and I realise there is no such thing as 100% safe.
What I have done probably wouldn't pass our very strict standards and I might end up in trouble over them if there were to be an accident but I'd rather be tried by 12 than carried by 6, your Honour.

BRENT in 10-uh-C · 04-08-2023, 10:39 AM

Quote:

Originally Posted by Synchro909

IMO, even if a seat belt pulls its mounts, it has still done some good. I'd still wear it than be totally unrestrained.

As for the body detaching from he chassis in a collision, I don't believe it. We have all seen lots of photos from the day of crashed cars, some quite seriously crashed. I haven't seen a one of them where the body detached. I regard that as an unsubstantiated old wives tale.
I have installed 3 point belts in both my Phaeton and my Tudor using the same method. There is no attachment point near my shoulder. I had made, a "Y" shaped belt that attaches to the strong box section at the very rear of the body, comes forward and forks just behind me with one arm of the Y going over each shoulder. The belt includes a lap belt component and when it is done up, it is like a racing harness. I thought about how to install a 3 point belt in the Phaeton for a while and came up with that. I liked it so much, I also used it in the Tudor. My CCPU and the farm Ute have lap/sash belts in them. The Ute ones are the modern recoil type.
I reckon it's all a game of playing the odds in a crash. I want to swing them in my favour as much as I can and I realise there is no such thing as 100% safe.

What I have done probably wouldn't pass our very strict standards and I might end up in trouble over them if there were to be an accident but I'd rather be tried by 12 than carried by 6, your Honour.

Two thoughts, and then I'll leave it at that....

Your first comment about "...it still has done some good" is one that IMO I doubt you can prove that. As mentioned above, in most impacts you have a sudden force that can easily be 3,000, 4,000, 5,000 pounds (-or more) of sudden impact across a 1½" - 2" area on your body. Kinda like an athlete swinging a baseball bat at full force across your stomach which can hurt you badly if the bat strikes in the wrong area.

Your comment about doubting that a Model-A body would come loose makes me realize you are just speaking from behind a keyboard and not reciting personal experiences of this. I am thinking about two Fordbarners that have been in accidents that brought their vehicles to us repair that know what you are saying is not a "wives tale". One took a shot to the L/F and it moved the front of the body over on the frame. The other was a Tudor that was hit in the rear. The bumper brackets folded when the other vehicle hit the rear section of the Model-A body and it took the impact. It moved the entire body forward where the firewall was against the back of the engine. Neither two of these instances are "wives tales".

Synchro909 · 04-08-2023, 05:41 PM

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Quote:

Originally Posted by BRENT in 10-uh-C

Two thoughts, and then I'll leave it at that....

Your comment about doubting that a Model-A body would come loose makes me realize you are just speaking from behind a keyboard and not reciting personal experiences of this. I am thinking about two Fordbarners that have been in accidents that brought their vehicles to us repair that know what you are saying is not a "wives tale". One took a shot to the L/F and it moved the front of the body over on the frame. The other was a Tudor that was hit in the rear. The bumper brackets folded when the other vehicle hit the rear section of the Model-A body and it took the impact. It moved the entire body forward where the firewall was against the back of the engine. Neither two of these instances are "wives tales".

So, you have seen two cars where the body moved on the chassis but didn't come off it. My point exactly.
Another factor in this is just how well were these cars restored? I've seen rusty, eroded bolts re used to hold down the body. Their strength was greatly reduced from original. Even if new bolts were used, how well were they tightened? I bought a car out of Arizona a few years ago and I don't think there was a bolt on it much more than finger tight. I can't see body bolts that loose holding the body securely.

30Murray · 04-09-2023, 06:45 PM

Gold Digger: pm sent

Thearne3 · 08-14-2023, 02:10 PM

At the risk of re-opening a 'can of worms', I would like to chime in because my significant other feels strongly that she wants seat belts in our '31 cabriolet and so I am doing my best to accommodate - and at the same time thread the needle between wishful thinking and doing some good.

Here are the points that I have understood so far:

1. Any significant crash is likely to be fatal, no matter what you do or do not do with seatbelts. (this is probably true for any car built before the '80's that does not have crush zones, air bags, etc!)

2. In a severe crash belts that are attached to the frame more securely than the body is attached may cause unnecessary internal injury when/if the body becomes detached from the frame.

3. Other than possibly the steel frame, there is no part of the Model A car and certainly no part of a Model A body that can withstand the 3000 lbs of instant force in a bad crash.

4. Installations in Model As often compromise on the appropriate geometry for attachment points, ie, the angles are not ideal and could cause spinal compression (if shoulder point is too low) or become 'loose' if the belt must get past a soft cushion)

5. Belts can create a false sense of security for the reasons noted above.

6. On the plus side, for less severe accidents belts may keep you in the car when doors fly open and may offer the driver stability that can help with maintaining control of the vehicle, eg, going over an unexpected bump at speed, the belt may keep you from bouncing around)

Having said all this I have some ideas for the a 3 point belt system for the front seat of my '31 68B cabriolet. (The rumble seat is a lost cause!) This model has an adjustable front seat. My idea involves installing a frame behind the seat using 1.5" steel tubing. A u-shaped tube is available that is 28" high and 41" wide. This means the horizontal bar of the inverted 'u' is about 3" above the top of the seat back. The feet are welded to steel plates that bolt directly through the body to the frame. A 1.5" crossbar is welded across the two legs of the inverted 'u' at the height of the seat bottom cushion. Finally, two 1.5" tubes are welded on the 'u' just below the package tray and run diagonally rearward down to and welded to plates at the body bolt just in front of the rumble seat.

The structure is therefore attached to the frame with a total of 4 bolts - two on each side. In order to address the body/frame detachment issue, I propose to replace ALL body bolts with the same high strength bolts - if some are sheared, all will (hopefully) be sheared.

The tubing frame does not interfere with the rumble seat passengers or their feet, but it is visible, just inside of the upholstered side panels. The top of the 'u' behind the front seat is largely invisible, even when the top is down, since the folded top is quite high. It sits directly in front of the package tray.

3-pt Seat belt attachment:

The low crossbar has 3 or 4 welded tabs and is at the appropriate height with respect to the laps of the driver and passenger. The center tab(s) is/are for attaching the two center seat belt pieces, which 'receive' the sliding seat belt piece. The side tabs on the cross bar each support the outside of the waist level, fixed belt, as well as the retraction mechanism, which is mounted vertically with the belt itself going up to the slider mounted on the top of the 'u'(the part that would be mounted on a door post in a modern car). For me, the shoulder slider is level with the top of my shoulder.

The benefits of this approach are:
1. the geometry of the belts is correct, with no 'slack'.
2. the tubing is typical of that used for roll cages for cars of this weight, ie strong.
3. viewed from the side, the 'triangle' formed by the tubes and frame should be quite strong for a front or rear collision.

I have all the material to begin this project and am hoping for input from the community. Is this description clear? What am I missing? Given that nothing is going to be perfect, is this a reasonable compromise, ie do the benefits offset the visible changes to the car?

Thanks in advance!

Lawrie · 08-14-2023, 03:29 PM

I would like to put belts in my 28ccpu,
But, and a big BUT ,is where on the body to attach the rear mounts, .
Lawrie

Pete · 08-14-2023, 03:41 PM

Roll bar and cage design is a whole subject by itself and requires a thick book to cover completely.
You are thinking along the right path but need more info.
An important thing to realize is, any crash protection structure that is not a compromise will in a street driven car be quite inconvenient for getting in and out of the car.

Probably the best info available for what you want to do would be the SCTA rule book. They run cars exactly like you are dealing with.

Thearne3 · 08-14-2023, 04:23 PM

Thanks, Pete.

I will check. Just to be clear my intent is not a cage or roll protection, rather a strong frame for properly securing the seat belts. I might add that this same frame could just as easily support a 4 point harness, but I thought that would be unnecessarily inconvenient for the relative benefit.

04-06-2023, 04:45 PM	#21
goldie Junior Member Join Date: Jul 2022 Posts: 25	Re: 3-point seat belts in tudor There is just so much that can be done to make a Model A safer. My main concern is not to be thrown out of the car. In the case of my woody, a rollover would result in a massive pile of wood shards that may impale me, compression fracture the last of my concerns. I drive a 1970 Jaguar E that sits very low, most modern car bumpers are at my eye level, and there is a greater chance of my demise in the Jag at speed than my puttering around in the A. Driving defensively helps the odds I hope. Enjoy while you can.

04-07-2023, 03:23 PM	#22
Ed in Maine Senior Member Join Date: May 2010 Location: Washington Cty., ME or Flagler Cty., FL Posts: 1,106	Re: 3-point seat belts in tudor There is a lot of good comments here. I have lap belts in my Victoria which go to the frame. I know that any serious accident in my Model A will result in me owning the farm! All I can say is that I drive very carefully and do not drive any faster than I have to, to meet traffic conditions. I have had 59 years of motoring in Model As and I have enjoyed every moment of them. I am hoping for another ten years before I have to give it all up. One thing I do like about my seat belts is that they keep me securely seated behind the wheel. There is none of that sliding around. My biggest fear is that door popping open on a turn and falling out. Ed

04-07-2023, 04:52 PM	#23
ModelA29 Senior Member Join Date: Sep 2022 Location: SoCal Posts: 591	Re: 3-point seat belts in tudor Many moons ago I did an article in Kit Car magazine on the lack of seatbelts in kit cars. I relied heavily on papers by the SAE (Society of Automotive Engineers). I looked at their site and they now charge for access to the papers but they may be available at a local library. Take a look at the testing limits and you'll see some of the problems you'll encounter putting in a strong enough anchor point. DYNAMIC TESTING OF SEAT BELTS 570045 TESTS simulating actual dynamic loading that a seat belt might receive during a crash of a motor vehicle are discussed in this paper. Design criterion was set as 20-g deceleration uniformly applied for 50 millisec. 150 pound driver @ 20g = 3,000 pounds in a sharp yank not a slow pull Biomechanics of Seat Belt Design 720972 This paper discusses the development of adequate criteria and evaluation methods for seat belt restraint design. These criteria should include the effect of seat belts in abdominal injury as well as head injury. It is concluded that belt load limiters and energy-absorbing devices should limit head-to-vehicle contact, ensure that the lap belt maintains proper contact with the bony pelvic girdle, and limit the belt loads. Studies are made of pulse shape and belt fabrics.

04-07-2023, 08:58 PM	#24
Synchro909 Senior Member Join Date: Jun 2014 Location: Melbourne, Australia Posts: 7,496	Re: 3-point seat belts in tudor IMO, even if a seat belt pulls its mounts, it has still done some good. I'd still wear it than be totally unrestrained. As for the body detaching from he chassis in a collision, I don't believe it. We have all seen lots of photos from the day of crashed cars, some quite seriously crashed. I haven't seen a one of them where the body detached. I regard that as an unsubstantiated old wives tale. I have installed 3 point belts in both my Phaeton and my Tudor using the same method. There is no attachment point near my shoulder. I had made, a "Y" shaped belt that attaches to the strong box section at the very rear of the body, comes forward and forks just behind me with one arm of the Y going over each shoulder. The belt includes a lap belt component and when it is done up, it is like a racing harness. I thought about how to install a 3 point belt in the Phaeton for a while and came up with that. I liked it so much, I also used it in the Tudor. My CCPU and the farm Ute have lap/sash belts in them. The Ute ones are the modern recoil type. I reckon it's all a game of playing the odds in a crash. I want to swing them in my favour as much as I can and I realise there is no such thing as 100% safe. What I have done probably wouldn't pass our very strict standards and I might end up in trouble over them if there were to be an accident but I'd rather be tried by 12 than carried by 6, your Honour. __________________ I'm part of the only ever generation with an analogue childhood and a digital adulthood.

04-09-2023, 06:45 PM	#27
30Murray Senior Member Join Date: Jun 2010 Location: Vancouver B.C. Posts: 111	Re: 3-point seat belts in tudor Gold Digger: pm sent

08-14-2023, 02:10 PM	#28
Thearne3 Member Join Date: Aug 2020 Location: Redding, CT Posts: 75	Re: 3-point seat belts in tudor At the risk of re-opening a 'can of worms', I would like to chime in because my significant other feels strongly that she wants seat belts in our '31 cabriolet and so I am doing my best to accommodate - and at the same time thread the needle between wishful thinking and doing some good. Here are the points that I have understood so far: 1. Any significant crash is likely to be fatal, no matter what you do or do not do with seatbelts. (this is probably true for any car built before the '80's that does not have crush zones, air bags, etc!) 2. In a severe crash belts that are attached to the frame more securely than the body is attached may cause unnecessary internal injury when/if the body becomes detached from the frame. 3. Other than possibly the steel frame, there is no part of the Model A car and certainly no part of a Model A body that can withstand the 3000 lbs of instant force in a bad crash. 4. Installations in Model As often compromise on the appropriate geometry for attachment points, ie, the angles are not ideal and could cause spinal compression (if shoulder point is too low) or become 'loose' if the belt must get past a soft cushion) 5. Belts can create a false sense of security for the reasons noted above. 6. On the plus side, for less severe accidents belts may keep you in the car when doors fly open and may offer the driver stability that can help with maintaining control of the vehicle, eg, going over an unexpected bump at speed, the belt may keep you from bouncing around) Having said all this I have some ideas for the a 3 point belt system for the front seat of my '31 68B cabriolet. (The rumble seat is a lost cause!) This model has an adjustable front seat. My idea involves installing a frame behind the seat using 1.5" steel tubing. A u-shaped tube is available that is 28" high and 41" wide. This means the horizontal bar of the inverted 'u' is about 3" above the top of the seat back. The feet are welded to steel plates that bolt directly through the body to the frame. A 1.5" crossbar is welded across the two legs of the inverted 'u' at the height of the seat bottom cushion. Finally, two 1.5" tubes are welded on the 'u' just below the package tray and run diagonally rearward down to and welded to plates at the body bolt just in front of the rumble seat. The structure is therefore attached to the frame with a total of 4 bolts - two on each side. In order to address the body/frame detachment issue, I propose to replace ALL body bolts with the same high strength bolts - if some are sheared, all will (hopefully) be sheared. The tubing frame does not interfere with the rumble seat passengers or their feet, but it is visible, just inside of the upholstered side panels. The top of the 'u' behind the front seat is largely invisible, even when the top is down, since the folded top is quite high. It sits directly in front of the package tray. 3-pt Seat belt attachment: The low crossbar has 3 or 4 welded tabs and is at the appropriate height with respect to the laps of the driver and passenger. The center tab(s) is/are for attaching the two center seat belt pieces, which 'receive' the sliding seat belt piece. The side tabs on the cross bar each support the outside of the waist level, fixed belt, as well as the retraction mechanism, which is mounted vertically with the belt itself going up to the slider mounted on the top of the 'u'(the part that would be mounted on a door post in a modern car). For me, the shoulder slider is level with the top of my shoulder. The benefits of this approach are: 1. the geometry of the belts is correct, with no 'slack'. 2. the tubing is typical of that used for roll cages for cars of this weight, ie strong. 3. viewed from the side, the 'triangle' formed by the tubes and frame should be quite strong for a front or rear collision. I have all the material to begin this project and am hoping for input from the community. Is this description clear? What am I missing? Given that nothing is going to be perfect, is this a reasonable compromise, ie do the benefits offset the visible changes to the car? Thanks in advance!

08-14-2023, 03:29 PM	#29
Lawrie Senior Member Join Date: May 2010 Location: Qld, Australia Posts: 4,216	Re: 3-point seat belts in tudor I would like to put belts in my 28ccpu, But, and a big BUT ,is where on the body to attach the rear mounts, . Lawrie

08-14-2023, 03:41 PM	#30
Pete Senior Member Join Date: May 2010 Location: Wa. Posts: 5,409	Re: 3-point seat belts in tudor Roll bar and cage design is a whole subject by itself and requires a thick book to cover completely. You are thinking along the right path but need more info. An important thing to realize is, any crash protection structure that is not a compromise will in a street driven car be quite inconvenient for getting in and out of the car. Probably the best info available for what you want to do would be the SCTA rule book. They run cars exactly like you are dealing with.

08-14-2023, 04:23 PM	#31
Thearne3 Member Join Date: Aug 2020 Location: Redding, CT Posts: 75	Re: 3-point seat belts in tudor Thanks, Pete. I will check. Just to be clear my intent is not a cage or roll protection, rather a strong frame for properly securing the seat belts. I might add that this same frame could just as easily support a 4 point harness, but I thought that would be unnecessarily inconvenient for the relative benefit.