When I worked at Precision Metalsmiths we cast in all sorts of metals. From Aluminum to Stelite. Temperatures affect molds, and wax. PM was the first to make any real use of plastic than wax. They took over the market on turbine blades. Wecreated stellite " needles" for high speed weaving machines. 1 1.8 " long with a 1 6/4 dia hole running thru it. It cut the cost of them over 80%. The mold held a porcelain "thread" which created the future hole when the wax surrounded it.. The heat of the Stellite steel affected it so you merely drilled out the "thread" residue from the steel casting.
The "tree" was coated with a higher heat resistent investment "plaster". then later the fask was filled with a cheaper invstment "plaster" to save money. Heating the casting metal correctly was critical. It is not a "basement" hobby project. John Armstrong ----- Original Message ----- . From: Alan Lambert To: [email protected] Sent: Friday, August 03, 2012 9:11 AM Subject: Re: {S-Scale List} Re: Another Update From Sergent - Enough is enough! From: Alan Lambert Fort Worth, Texas John, I used to work in an alluminium foundery and know first hand what goes into making molds. Ours were for a storage tube cap that you see on gas station refueling trucks where they store the hoses. Of cource these were not investment castings. They used them over and over, and when the order was filled put the molds back in storage until the next order. How do I know, I helped make some of the molds. I think that is what the hang up is with his molds. He has to find a way to keep the price of the final product down and a easy way to do the castings for multi different parts on the same tree. Alan From: John Degnan <[email protected]> To: [email protected] Sent: Friday, August 3, 2012 6:13 AM Subject: Re: {S-Scale List} Re: Another Update From Sergent - Enough is enough! Thank you, brother S scaler Alan. Yet another voice of logic and reason. Very glad you're on board. John Degnan [email protected] [email protected] ----- Original Message ----- From: Alan Lambert To: [email protected] Sent: Thursday, August 02, 2012 08:10 PM Subject: Re: {S-Scale List} Re: Another Update From Sergent - Enough is enough! From: Alan Lambert Fort Worth, Texas John, I also agree with Michael.And as you have stated the problems that have popped up, we need to chill out and waite. Anybody that has done castings knows of the drawbacks that can and will happen. We all need to give Sergent a break and in the long run we will see something. Investment casting is not that easy when you are faced with what he has run into. The molds have to be changed to do that. He is working on that, and I for one will give him chance. You have helped alot also. Alan From: John Degnan <[email protected]> To: [email protected] Sent: Thursday, August 2, 2012 6:37 PM Subject: Re: {S-Scale List} Re: Another Update From Sergent - Enough is enough! The sound of logic and reason. Thanks Michael. John Degnan [email protected] [email protected] ----- Original Message ----- From: Michael Ostertag To: [email protected] Sent: Thursday, August 02, 2012 07:19 PM Subject: Re: {S-Scale List} Re: Another Update From Sergent - Enough is enough! Ok, so since I am "new" (November of 2011) to S Scale, here is my view on this. I originally planned on equipping all my rolling stock and locomotives with sergent's couplers. Now since they aren't currently available, I asked some folks if they had some they weren't going to use and received a few in the mail. Now two or three pair, isn't going to make a railroad run very well. So....I have turned to KD's 802 in the interim. Now once the Sergent couplers are available on a regular basis, I will re-equip my rolling stock and locomotives with the sergent couplers and put the KD's up for sale. This to me is the best compromise. If for some reason things fall completely apart at sergent and they don't come out at all, I'm still going to be able to run my railroad. Michael Ostertag __________ Information from ESET NOD32 Antivirus, version of virus signature database 7350 (20120802) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
