too tight crowns for PFMs

Baker · 02-07-2008, 12:12 PM

Need to know what the labs are using as far as investment for PFM's. We are getting to tight of fit. Looking for an investment that is stable and that will fit. We use ringless, fastfire investment, and up to 4 wax patterns per ring (90gram rings). Please inform me what investment you use, How many wax patterns you use in a 90gram ring , fast burn out or slow? And what is a good noble metal and investment?
Thanx for your help.

clearH2O · 02-27-2008, 02:31 AM

Hi Baker, I use Bego investment. Tight fit may start from die, from wax, from burn out technique, from investment or metal. To my opinion, check your die stone expension first then check your water/powder ratio. You may add die spacer to loosing the fit. Check your metal expension too. For investment, water will do the trick to expension. More water>>>less expension and less water >>>more expension. I use both techniques fast and slow and follow strickly to manufacturer directions. Depend on its sizes I can add or reduce the number of wax paterns in 90gr ringless mould. Jensen Nobble metal I use giving me good result for my PFMs and that is all I can say to response to your question. I hope its help.

02-07-2008, 12:12 PM	#1 (permalink)
Baker Junior Member Join Date: Nov 2007 Posts: 7 Gallery: 0 Rating: 0% (0) Rep Power: 0	too tight crowns for PFMs Need to know what the labs are using as far as investment for PFM's. We are getting to tight of fit. Looking for an investment that is stable and that will fit. We use ringless, fastfire investment, and up to 4 wax patterns per ring (90gram rings). Please inform me what investment you use, How many wax patterns you use in a 90gram ring , fast burn out or slow? And what is a good noble metal and investment? Thanx for your help.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

02-27-2008, 02:31 AM	#2 (permalink)
clearH2O Supporter Join Date: Oct 2007 Location: LA, California Posts: 27 Gallery: 0 Rating: 0% (0) Rep Power: 0	Hi Baker, I use Bego investment. Tight fit may start from die, from wax, from burn out technique, from investment or metal. To my opinion, check your die stone expension first then check your water/powder ratio. You may add die spacer to loosing the fit. Check your metal expension too. For investment, water will do the trick to expension. More water>>>less expension and less water >>>more expension. I use both techniques fast and slow and follow strickly to manufacturer directions. Depend on its sizes I can add or reduce the number of wax paterns in 90gr ringless mould. Jensen Nobble metal I use giving me good result for my PFMs and that is all I can say to response to your question. I hope its help.