Old Carriage Bolts

[will-max dairy]

I've found a couple of instances now, on old (>50 years) equipment.

Where:

A: either old carriage bolts had a bigger square relative to the shank

or

B: the square broached into the equipment for the carriage bolt corroded to a larger, perfect square


The most recent was our old 2N tractor. The big old U-shaped "spring" for the seat cracked. We bought a new one from this site. (which was a perfect form, fit and function replacement)... but the carriage bolt in our 2N's seat was not recoverable. We had to cut the old bolt out.

No problem, I thought; since I have quite a few 1/2" carriage bolts on hand.

But... the square on the new 1/2" carriage bolts are exactly the size of the shank... as in... 1/2" round shank... 1/2" square under the head... the old bolt seemed to have a bigger square, relative to the shank.

Am I crazy? (Wait, don't answer that)... but... is this a thing? Or is there another class of carriage bolts with even flatter heads and fatter squares for these uses?

(edit... I just remembered the other place where I ran into this... the brackets that hold the teeth on our NH56 rake. I bought about 20 new brackets and teeth for it last summer... Each one was fastened by a carriage bolt... I wanted to buy new carriage bolts... but when I bought new carriage bolts that matched the shaft diameter of the old... the square heads didn't lock in the brackets... I had to buy 1/16" larger diameter carriage bolts to get a good lock in the brackets... this also meant that we needed to have a drill on hand to ream the holes in the bar just a little, in a few instances)

 

[M-MAN]

Yes there are carrige bolts with the square bigger than the shank. We used to use them on looms in the old days. Back then almost all of the machines were put together with carrige bolts.

 

[will-max dairy]

Yes there are carrige bolts with the square bigger than the shank. We used to use them on looms in the old days. Back then almost all of the machines were put together with carrige bolts.

M-MAN

I need to find a couple of instances and put a caliper on them or something, because it doesn't seem as though something like this could have changed... I would like to think that the dimensions of a "carriage bolt" have remained constant... but like I said... a couple of times recently I've been bamboozled.

 

[stevieb49829]

Will-max, I also have run into the size M-Man is talking about, mostly in the old, wood framing in antique car bodies. I'd have to go look through my "carriage bolt" can, but I might have one or two in the 5/16 or 3/8 realm. steve

 

[will-max dairy]

Will-max, I also have run into the size M-Man is talking about, mostly in the old, wood framing in antique car bodies. I'd have to go look through my "carriage bolt" can, but I might have one or two in the 5/16 or 3/8 realm. steve

Is there a way to specify this?

(anyway... this might be a figment of my imagination... I tried to ask this question a couple of ways in Perplexity... and the jist of what I got is that carriage bolt dimensions have been stable since the 1990 adoption of ASME B18.5; and it says that bolts made in, say 1940 would "likely" have the same relative dimension of the square neck to the shaft diameter)

 

[stevieb49829]

Is there a way to specify this?

I really don't know. But a good place to look for this kind of oddity with specs would be online at Mcmaster Carr.

 

[Watthour]

A.O. Smith used to use oversized square carriage bolts on their Harvestores and bolted tanks. After about 30 years they switched to an oblong collar to minimize the crazing of the porcelain/glass coatings which would introduce fatal rust locations. Those old square collars may be something still available in some places.

 

[Charles in Aus.]

Older carriage bolts were also used in timber bed bases from the 1920s . The type that used woven spring wire mesh as support . The bolts had very large square shoulders and often used square nuts along with thick large diameter washers .
I still have a remnant of one of these bases that I use for sieving stones and rubble out of garden soil .

 

[jwal10]

Bolt made for the special application....James

https://www.nnalert/tractors/sheet-...lXtBePhEUz05nZ4S0SDpMD_WDQD0hjiRF4NrOub2-2nWI

 

[Fixingfarmer]

Some (actually quite a few)of the carriage bolts used in the 30s would be this way. John Deere has a selection. It’s not stock that turns over rapidly so some of that is still inexpensive. The seat application on my 38 b same issue. I had to get a part number and ended up with a couple wrong ones first

 

[sms]

Try Blacksmithbolt.com they have three types of carriage bolts, traditional, modern, and stainless steel.

Traditional Carriage Bolts

Traditional Carriage Bolts have either no head marks, or a simple head mark or two. They also have partial threads with a full body beyond the threads (short lengths can be fully threaded). We offer them in a traditional Black Oxide finish. Because we can no longer find adequate supplies of old...

blacksmithbolt.com

 

[caterpillar guy]

I have not found a job for carriage head bolts that was worthy of such none sense with the head turning and all that junk. At least with a head you can put a wrench on to hold it from turning . Not a carriage head bolt they seem to always turn when taking them out whether in steel or wood. I usually grind off the head and use a regular hex head bolt. Problem solved.

 

[M-MAN]

I have not found a job for carriage head bolts that was worthy of such none sense with the head turning and all that junk. At least with a head you can put a wrench on to hold it from turning . Not a carriage head bolt they seem to always turn when taking them out whether in steel or wood. I usually grind off the head and use a regular hex head bolt. Problem solved.

You're talking about modern carrige bolts. The op is talking about carrige bolts with heavy shoulders that did not turn. Big difference.

I don't remember a shoulder ever rounding off on the looms I worked on in my youth and the whole loom was built with them.

 

[Jim.ME]

I have not found a job for carriage head bolts that was worthy of such none sense with the head turning and all that junk. At least with a head you can put a wrench on to hold it from turning . Not a carriage head bolt they seem to always turn when taking them out whether in steel or wood. I usually grind off the head and use a regular hex head bolt. Problem solved.

Does a hex head bolt, in place of a carriage bolt, in the middle of a metal pan seat help hold you in the seat? That was the carriage bolt use in this thread.

 

[Jim.ME]

Is there a way to specify this?

(anyway... this might be a figment of my imagination... I tried to ask this question a couple of ways in Perplexity... and the jist of what I got is that carriage bolt dimensions have been stable since the 1990 adoption of ASME B18.5; and it says that bolts made in, say 1940 would "likely" have the same relative dimension of the square neck to the shaft diameter)

I agree the squares were different on some of the older carriage bolts. That said, how long are you going to spend chasing one bolt for one seat? Needing 25 or more for a restoration would be different. In a case like this, one bolt, I would spend a few minutes with a welder, grinder, and file to fit the new carriage bolt square to the old hole, then move on to the next real problem. JMHO

 

[will-max dairy]

I agree the squares were different on some of the older carriage bolts. That said, how long are you going to spend chasing one bolt for one seat? Needing 25 or more for a restoration would be different. In a case like this, one bolt, I would spend a few minutes with a welder, grinder, and file to fit the new carriage bolt square to the old hole, then move on to the next real problem. JMHO

Actually, the seat is already done. We just made do with what we had.

 

[will-max dairy]

I have not found a job for carriage head bolts that was worthy of such none sense with the head turning and all that junk. At least with a head you can put a wrench on to hold it from turning . Not a carriage head bolt they seem to always turn when taking them out whether in steel or wood. I usually grind off the head and use a regular hex head bolt. Problem solved.

Most NH baler bale chambers use carriage bolts for just about everything; and of the many, many ones that I've removed/replaced during service/maintenance; I can only remember maybe one time that the square shoulder didn't hold.

Where I AM seeing an issue recently is haybine guards. I install them with the head and shoulder on the bottom and threads pointing up. This means that the carriage bolt shoulder needs to hold in the square hole in the guard; and... this has become a little dicey in the last few years.

 

[Tom Massachusetts]

Elevator bolts have a larger square with a larger flat head. I have used them to replace old carriage bolts.

 

[Keith Williams]

Most NH baler bale chambers use carriage bolts for just about everything; and of the many, many ones that I've removed/replaced during service/maintenance; I can only remember maybe one time that the square shoulder didn't hold.

Where I AM seeing an issue recently is haybine guards. I install them with the head and shoulder on the bottom and threads pointing up. This means that the carriage bolt shoulder needs to hold in the square hole in the guard; and... this has become a little dicey in the last few years.

The guards on my NH 451 mower use plow bolts. They come up from the bottom.
HTH

 

[wore out]

I've found a couple of instances now, on old (>50 years) equipment.

Where:

A: either old carriage bolts had a bigger square relative to the shank

or

B: the square broached into the equipment for the carriage bolt corroded to a larger, perfect square


The most recent was our old 2N tractor. The big old U-shaped "spring" for the seat cracked. We bought a new one from this site. (which was a perfect form, fit and function replacement)... but the carriage bolt in our 2N's seat was not recoverable. We had to cut the old bolt out.

No problem, I thought; since I have quite a few 1/2" carriage bolts on hand.

But... the square on the new 1/2" carriage bolts are exactly the size of the shank... as in... 1/2" round shank... 1/2" square under the head... the old bolt seemed to have a bigger square, relative to the shank.

Am I crazy? (Wait, don't answer that)... but... is this a thing? Or is there another class of carriage bolts with even flatter heads and fatter squares for these uses?

(edit... I just remembered the other place where I ran into this... the brackets that hold the teeth on our NH56 rake. I bought about 20 new brackets and teeth for it last summer... Each one was fastened by a carriage bolt... I wanted to buy new carriage bolts... but when I bought new carriage bolts that matched the shaft diameter of the old... the square heads didn't lock in the brackets... I had to buy 1/16" larger diameter carriage bolts to get a good lock in the brackets... this also meant that we needed to have a drill on hand to ream the holes in the bar just a little, in a few instances)

I think you are thinking generic "carriage bolts" like you'd get from a hardware store vs. specialized bolts for a certain specific job.

I wouldn't expect a generic "carriage bolt" from a hardware store to hold down a pan seat or attach teeth to a rake, for that sort of stuff you need the special bolts the OEM used for that specific job.