Pontiled Black Glass

Re: RE: Pontiled Black Glass

Well I have at least two dozen black glass bottles and a lot of pictures of pontil marks in my computer. There were so many different things done in the development of hand bhlown glass bottle making - that it blows my mind on how to cover the things seen. It is like the things that have shown up in the concept of turning the hot glass in the mold to reduce the mold seams. The factors of twist marks under the finish and in the neck glass to the turn and lift marks on the straight side all - made in the action. As well ass the embossed bottles that were turned in the mold with embosing on the bottomsl, where they thought lifting would release the lettering - [It doesn't always!!!] It is still a fun hobby to study the old glass examples. RED M.

Re: RE: Pontiled Black Glass

Well I just read through all of this thread. I also have read a lot of books on the subject.I know one of my books indicated that they used a box of different fine materials in several divided box sections. One for sand, one for fine chips and dust of fractured glass, one with graphite, and I realize that a lot of things were not recorded or completely explained. I must have a couple hundred p9ctures of different pontil surfaces, and have tried to illustrate makers marks and mold venting description. I m sure that some vent dots are not lost in the empontilling. There is a lot of justification for better descriptions of what was done. I looked through over a dozen black glass bottle bottoms yesterday, and there are always thoughts of wondering how it was really accomplished. It is fun though - and keeps me in my bottle den away from too much beer or sleeping. RED M.

Re: RE: Pontiled Black Glass

Well guys, Asterex and Tigue : I have posted a deicripton of pontlls before on the ABN. I have been thinking about looking back in my computer subjectfioes and brining it up for re write. I think I could review it and expand on it with mor information from four years of study and review. All four of these bottles now have a full page write up of description and I need to type it and maybe post them. The problem is - it will be a typing project. How ever there is a lot of difference in many points of these differences. We will work on it. I am doing this on about 6 or 700 hundred glass items I have here in mu den - right now. I have to do it so my daughter will know what they are when she has to sell them. I havfe a lot of different types of glass items that all need to be done. To help you guys I will work on these four next. Because I think these old ones I have are all 3 to 400 $ bottles in today's market - though I think the money shortage won't get it right now. All four of these have different - similar pontils for the different shapes of the bottoms have a difference in form. I have three people pushing me to put together a bgook on the old bottle making. After reading fifty or so old books written on bottle making and bottles collections, it lookis like a gigantic job. Scarry - too hair standing fear. There has to be a couple hundred different finishes. Different types, different seals, different handle applications, Different mold metals and foundry practices to create the dendritic irond, which we went to to make the mold glass contact areas stay hotter. The different mold metals for all glass contact that we went to for different reasons. And a lot of mold work we did to create special things - like the molds I had made with electro- formed nickel mold cavities we mounted in iron mold outer carrying holders. The special mold metals we applied to machine made mold components, and a skidillion things I have worked on. My wife (Better Half). thinks the only thing I know is bottles. Da!So I do have a paper started on pontil differences - and other subjects.Well that is enough prattle. RED Matthews

Re: RE: Pontiled Black Glass

Well I have four early AMERICAN black glass bottles here on the floor, that I have write ups - to type up. I will have to get my camera working also. One has a vent dot that had clearance for the vent dot in the punty rod. One of these bottles was made in a three part mold - and the bottom mold casting cavity could not be chilled when the hot metal was poured, because the chilling iron couldn't have been removed. This made a bottle with nice smooth shoulders and the body of the bottles lower section looks horrible with cold mold ripple in the glass.I have covered that in another posting in my home page. The dendritic structure in chilled cast iron slows the mold cavity cooling of the glass solidification, and does away with cold mold ripple in the glass. It would be impossible to Knock the chill out - it would have to be machined out. Fun stuff to have the bottle tell you. RED M.

Re: RE: Pontiled Black Glass

Well have a lot of pontiled glass and l have a lot of books with bits of information. A few years ago I made a post about a box that was about four foot long that had dividers in it for sand, glass dust particles, fine broken glass particles, and graphite - in each of the sections. This was in a book I had read and I can't find it now. When I go to Pontil s Only - I see a request for this subject coverage. It is on my list of things to do. REDM>

Re: RE: Pontiled Black Glass

I have four bottles here by me on the floor. I made write-ups on leach of them an just now looked at the bottoms. to get to the one with a flat outer contact ring. This one is 1/2" wide. This bottle was made in a three mold set up. It has a 2-1/2" domed center cavity with a large vent dot in the center of it. The dome is about 5/8" deep. There is a vent dot in the denter, and the dome form was empontiled with a 3" stickey ball pontil that had a clearance hole for the vent dot. The vent dot is very smooth and didn't get any pick up of pontil specks. An interesting thing about this bottle is that the shoulder mold iron was chilled with dendritic iron mold cavity metal - so the glass is nice and smooth, with the seams showing. The bottom part of the mold was cast iron, that couldn't be chilled, because this is a one piece cast iron tube and the core cavity could not be chilled by pouring the molten metal against a cold iron center core. So the glass in that portion of the bottle has "Cold Mold Ripple" in the glass thickness of that lower part of the bottle. This glass condition was covered in my home page - chilling the molten cast iron metal creates a half inch to a 3/4" of the hot glass contact area. Chilled iron in this zone slows the heat extraction from the glass, and this change in making bottle molds - was what did away with the thickness differences in early glass - that people called whittle. And you don't whittle cast iron.
So - I will be interested in your reactions to this explanation. RED Matthews

So

Re: RE: Pontiled Black Glass

So I have a few of these bottles, and I have seen a lot of empontilling that had clearance for the vent dots. I see the application of sand and/or glass dust in the pontiled dsurface. There just doesn't seem to be any books that describe enough for us. I have one book that illustrated a long wooden box with fivre different sections to hold iron dust, sand, gine grlound glass and graphite in sections of the box, So that satisfied me = because of the options. to the job do'er at the time. I just can't find which book it was in. RED Matthews

Re: RE: Pontiled Black Glass

Well I have not seen any good review of these pontil marks, I have sde veral of them ande also have noticed that a lot of them have a taopered finish with a semall tapered section under the finish from the same tooling. i am also confused about the sources of these similar bottles - from north to south. At least the double tapered finish is American. RED Matthews