The Iron Pontil

[hemihampton]

For an in depth info on pontils check the "HISTORIC BOTTLE" website

what Historic Bottle website?

 

[Semar]

Don't you love it when that happens.

 

[INK]

For an in depth info on pontils check the "HISTORIC BOTTLE" website

 

[INK]

what Historic Bottle website?

Correction -

Historic Bottle Identification​

 

[jwpevahouse]

Correction -

Historic Bottle Identification​

I find it interetsing that no contemporary glass blowing operations produce bottles with anything even similar to an :"iron pontil", The Clevenger Brothers bottles usually have a broken glass type pontil. They were old time glass blowers trained in the big glass works of South Jersey. If the "iron pontil" was useful to old time glass blowers why was it completely abandoned by successive glass blowers? I haven't seen a bottle produced in the last 150 years with an iron pontil. My guess is purely cosmetics, a better looking bottle sold better. There was definitely intense competition among glass companies to produce a better looking product.

 

[sandchip]

I find it interetsing that no contemporary glass blowing operations produce bottles with anything even similar to an :"iron pontil", The Clevenger Brothers bottles usually have a broken glass type pontil. They were old time glass blowers trained in the big glass works of South Jersey. If the "iron pontil" was useful to old time glass blowers why was it completely abandoned by successive glass blowers? I haven't seen a bottle produced in the last 150 years with an iron pontil. My guess is purely cosmetics, a better looking bottle sold better. There was definitely intense competition among glass companies to produce a better looking product.

The iron pontil was considered an improvement over the glass-tipped blowpipe or solid rod pontils, but was soon abandoned for the much quicker snap, which produced an even cleaner bottle. Most modern blown glass doesn't lend itself to the use of snaps, usually because of the decorative, many times bulbous proportions, so the solid rod naturally became the pontil of choice. As a side note, I believe where the blowpipe was used to empontil a bottle, there were actually two blowpipes being used, the one used to actually blow the bottle, and the one used to blow the previous one, having been propped in the furnace opening to keep the glass on the tip soft. The blowpipes were alternated back and forth. We've been taught for decades that the blowpipe used to empontil was dipped in the hot glass each time, which I believe is hogwash, and would've been a time drain in a production oriented workplace.

 

[jwpevahouse]

The iron pontil was considered an improvement over the glass-tipped blowpipe or solid rod pontils, but was soon abandoned for the much quicker snap, which produced an even cleaner bottle. Most modern blown glass doesn't lend itself to the use of snaps, usually because of the decorative, many times bulbous proportions, so the solid rod naturally became the pontil of choice. As a side note, I believe where the blowpipe was used to empontil a bottle, there were actually two blowpipes being used, the one used to actually blow the bottle, and the one used to blow the previous one, having been propped in the furnace opening to keep the glass on the tip soft. The blowpipes were alternated back and forth. We've been taught for decades that the blowpipe used to empontil was dipped in the hot glass each time, which I believe is hogwash, and would've been a time drain in a production oriented workplace.

The gaffers were paid by production. They were eager to accept any techniques which might improve their production. The glass works management had to compete to survive, and I think quality became one important selling point for their product. Advertisements sometimes made claims of "a better finished off bottle" than their competition. Those things together produced the improved quality of post 1880 sodas and beers. The ugly pontil mark on the bottom of the bottle and applied lips had to go. They were in business to make money.

 

[Semar]

I also have to wonder how many 'blowpipe' pontils cracked the bottle's base area when broken off during the manufacturing process due to differing temperatures of the materials involved. The use of the iron pontil would probably cut down on defective bottles.
(am I making any sense here?)

 

[sandchip]

I also have to wonder how many 'blowpipe' pontils cracked the bottle's base area when broken off during the manufacturing process due to differing temperatures of the materials involved. The use of the iron pontil would probably cut down on defective bottles.
(am I making any sense here?)

I doubt that there were many if I'm correct in the two blowpipe theory and that the glass tipped end was kept hot for adhesion in the furnace opening. I believe that the search for an improved pontil stemmed more from eliminating the risk of the sharp scar protruding from the bottle's base cutting a consumer during everyday use.

 

[jwpevahouse]

I also have to wonder how many 'blowpipe' pontils cracked the bottle's base area when broken off during the manufacturing process due to differing temperatures of the materials involved. The use of the iron pontil would probably cut down on defective bottles.
(am I making any sense here?)

I've seen plenty of bottles which appear to have damage, particularly around the lip or on the bottom caused during manufacture. Old photos of gaffers working will often have a large barrel full of broken glass sitting near the blowing station. There were apparently plenty of rejects.