frame sag

Bronco said:
Their is small kink in the lower frame rail about 5 inches in front of the motor mounts. Noticed the issue due to change in hood spacing between gas tank an radiator.
Bronco
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Good job of measuring. As pat says, that is the start of the tapered part of the frame at the front. You will see a taper at the rear portion of the frame also. The only valid place to check for sag is the top rail of the frame with a straight edge (unless someone knows about a trick that I don't).

Someone did! String or fine wire in lieu of a straight edge.
 
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without seeing a photo of your hood, it would be hard to say what is causing the recent misalignment. However, rather than a frame sagging so soon after it was OK, I would expect the soft rubber mount pads have crushed a little. The repop pads are nothing like the originals. They are soft rubber. The originals were firm rubber with a cloth webbing in the center. I found some sheet neoprene at the local hardware store that was more like the right stuff. They hold up pretty well when made of that stuff. If your hood gap is greater at the lower end than at the top, check the rubber pads under the forward cowl. Raising this area will bring the hood gap closer at the bottom. It will affect the doors too. If you can post a photo of the gap that concerns you, we can give you a better answer.
 
SSsssteamer said:
The frame was bent cold. Then straighten it cold and it will go right back to like it was before the bend. Putting heat to the frame could anneal the frame and make it softer and easier to bend where the heat was applied. Putting heat to the frame will straighten it only where the heat is applied. The actual bend covers a longer area than just the small heated area. Chain down the frame ends and jack up the sags to straighten again. When I was a kid on the farm, it was always fun to see how much air we could get with the old cars. We did bend a few frames. Puckered body panels, ill fitting doors and hoods, and broken motor mounts were the immediate results of our wild entertainment.
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While he frame will be straight it will not be like it it was.
Metal stretchs when bent cold it does not shrink.

So the frame metal streched on the bottom of the frame and the when you cold bent it back you strech the top.
 
Also, annealing can happen from heating, but it happens first if the metal is brought to it "critical" temperature. Then the length of time it is cooled comes into play. What I am saying is that just because a piece of steel is heated, doesn't mean annealing will take place.
 
Here is a ad from years ago. Where does it state the engine is the 4th cross member. None. Tony FordFrame[1].jpg
 
From an engineering perspective it stands to reason that a solid bolted piece f cast iron will strengthen that area. Ads do not always tell everything. The float a motor mounts will weaken the structure. I guess the debates is as to how catastrophic it will be. They have been around for a while so I am guessing it is borderline.
 
There is an article floating around in restorer or man of the engineering behind the frame design and the importance of the original type motor mounts. Very interesting article, but I cant remember what issue it was in. Maybe someone who also remembers the article can shed light as to where to find it. My roadster vibrated aweful with the fam mounts installed before i bought it, put originals on and it is smooth as butter. F.A.M.'s are a band-aid for other issues.
 
Steve Wastler said:
There is an article floating around in restorer or man of the engineering behind the frame design and the importance of the original type motor mounts. F.A.M.'s are a band-aid for other issues.
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Steve,
I would love to read it! My FAM's are used more for preventive medicine rather than a band-aid, band-aids are for wounds and my balanced, counterweighted engine is far from wounded. The only thing my engine lacks is a vibration dampener to take care of any torsional vibrations that may be present.

Frank,
It isn't solid bolted, the mounts are in rubber at the frame rails and the whole concoction is approximately two feet away from the frame center crossmember which Ford did tout.
 
Milton, I was not trying to imply your A needed a band-aid or you were using them as such. It seems as though most who question the use of original mounts or the importance of them in the engineering of the frame are guys who tend to modify from stock. Henry went to great lengths to constantly improve the 'New Ford'. The use of FAM mounts to 'solve' issues with a stock A is what I was referring to as the band-aids, I should have been a little more specific. Was not trying to offend anyone. I will try to locate the article of the engineering of the frame, the information is very enlightening, and a must read for all.
 
Steve Wastler said:
I will try to locate the article of the engineering of the frame, the information is very enlightening, and a must read for all.
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Steve,
Besides the comradery, I am here for enlightenment, and to hopefully help those with needs. If this matter can be settled once and for all I will be extremely grateful. As I recall from, I think it was the Ford Garage, I read about the very early A's using a flex mount, that Henry shot down because he didn't like to see the motor movement. I have looked for the answer about the pro's and con's about FAM's and, like Brent in 10-uh-C, I am interested in "just the facts" not the beliefs.

By the way, no offense was taken from your first post, and to be honest the FAM's were originally exactly as you describe, a band-aid applied by the previous owner before I corrected the sources of the vibrations. They are still in place, I like them and intend to keep them if there is not a down side.
 
I have used floatamotors for 14,000 miles in smooth and rough conditions. I have not noticed any sag,but I also use a rear mount.
 

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