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Glass blowing molds

Dear Sirs Hi I am looking for some info on glass molds for blowing. I work for a large Lamp Co in Miami Fl one of our dept is a glass blowing and slumping.Myself I only know a little about glass as my background is mold making ceramic, silicone and the like. Even thou I helped set up the glass dept and build the glass tanks and use to charge the glass at night before leaving that is about as far as my knowledge goes. When we first started to do glass we were melting marbles in side our ceramic kilns. I was making the one use waste molds for the glass out of plaster EPK and vermiculite some one found the mix in a glass book. That guy is long gone and I don't have the formula any more it has been like 9 years since we needed molds like that. The glass dept moved on to machined Graphite molds and metal molds. So my hands have been out of the glass for around 6 years. Do you have any idea were I can find the formula? (plaster EPK and vermiculite mix) Book web site or do you know of it and can please you share it.

Next they are looking at the cost of the metal molds we have to have made 2 to 3 thousands dollars each and they are looking to find a cheep way to make the molds so I was ask to look for fast easy ways to make the molds. I have some ideas and I am wondering if they will work or if you or any one you know has tried them. All the ideas relate to glass blowing molds. All molds will be from 1 to 4 parts.

1.Ceramic molds like used in slumping the mold will be in 3 to 4 parts. Because of undercuts. 2.Refractory like ZerCar can it be molded and will it last for say 50 blows. 3.Plaster EPK vermiculite mold. 4.Polyurethane mixed with metal powder 5.Epoxy mixed with metal powder 6.Graphite molds is there a way for me to make mold using it. I Would like able to pour it. 7.Do you have any ideas that may be of help.

Thank You Rodney Rock Master Mold Maker / Design Fine Art Lamps Miami Lakes Florida Phone 305-821-1055 EX 3065 Work Email snipped-for-privacy@fineartlamps.net Home Email snipped-for-privacy@gmail.com Web Address

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Reply to
rodlrock
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Looking at your list, I have start with Are you blowing the molds per your title or in line 6, you say you want to pour? What are you making? Shades? Parts? How big. The plaster, EPK, vermiculite should be a very low use mold. The EPK would make it more clay like while the vermiculite is usually an insulator. Graphite is used for pour and press molds. Iron would give more multiple uses per mold but requires special preparation. Epoxy or polyurethane won't work, will burn. Because ceramic shrinks, you will have to work to scale - casting oversized, shrink on drying and firing, but you probably know that.

Reply to
Mike Firth

Mike We are blowing glass. What thay are looking for a cheep way to make the blowing molds.As the metal molds we are using now are very costly. 99% of our glass parts are brand new so molds need to be made One type of part is a small shade to very large 2' to 3' tall and very fat. this is but one style at the link below.I will take some photos at work and send them to you if that will help.

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So MuchRodney Rock

Reply to
Rodney

should have been. What thay are looking for is a cheep way to make the glass blowing molds.

Reply to
Rodney

Henry?

Reply to
Javahut

Henry Thay are looking for real cheep mold alturnatives.

Reply to
Rodney

Reply to
Terry Harper

Molds for blowing do not have to be from steel, aluminum works fine. If your looking for precision molds though you will have to have a mold maker familiar with the glass blowing process fabricate the model and then have the blow mold cast. Nothing of quality comes cheap though. Obviously a 1 part mold is going to be a lot cheaper than say a 4 part mold. The company your looking for is Steinert Industries in Kent, Ohio.

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As far as waste molds are concerned youcan use 1:1 plaster/silica 200 mesh by weight. This type of waste mold hasbeen used since the 19 century. The formula your looking at is used forbronze casting. Slump molds can be fabricated from most any type of clay andthen bisque fired. Keep in mind though you cannot make the clay excessivelythick. Clay slump molds are usually less than 1/2 thick. I would notrecommend blowing into Zircar as you really cannot put a great deal ofpressure into the blow because the Zircar is really not a rigid product.Zircar is good for multiple castings if you do not have any undercuts.Graphite is not bad for pour molds but cannot be used for casting thatrequires you to put the graphite in the annealer and leave it there for theextent of the annealing and cooling cycle. The graphite binder willdeteriorate and the mold will fall apart in short order. .

Reply to
Henry Halem

Go with Henry's advice - he knows more about casting than any other 9 people likely to be on here.

Reply to
Mike Firth

Wow you guys are really helpful this the kind of feed back I need I will be getting the book Glassnotes.Thanks for all you reples please keep them coming Thanks Rodney

Reply to
Rodney

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