Arrggghhhh!

[CatamountRob]

I didn't need that freakin' hole there!!

 

[2thm8kr]

Well then why did you put it there?

 

[CoolHandLuke]

also your margins are short on 2 dies at least (that we can see)

 

[CatamountRob]

Well then why did you put it there?

Good question.

 

[zero_zero]

Why did you bother fitting it ?

 

[rkm rdt]

I see you went with exocad

 

[sidesh0wb0b]

holy hell is that quick check green all over the place?
ive not had to work metal that much since i was a weeeee bebbie!

 

[Getoothachopper]

Don't look at it 'as a hole',,,,,,,,Look at is as an opportunity for an 'extended porcelain margin'

 

[CoolHandLuke]

ah oui, c'est magnifique.

 

[Getoothachopper]

LOL

 

[Juko]

Well heat your alloy better next time. Also Is that investment breakdown in the left one near the sprue? The white speck.

 

[Getoothachopper]

Well heat your alloy better next time. Also Is that investment breakdown in the left one near the sprue? The white speck.

I think it's the tip of the die peeping through

 

[Juko]

I think it's the tip of the die peeping through View attachment 22366

I didn't notice the blue.

 

[GarryB]

Wow, you are very brave with how close you de sprue!!

 

[CatamountRob]

Why did you bother fitting it ?

Because it's an easy fix with Ree-Cast, fill it with the matrix material, warm it in a furnace, flow a bit of solder into the matrix.

Don't look at it 'as a hole',,,,,,,,Look at is as an opportunity for an 'extended porcelain margin'

They are to have porcelain facial magins anyway, I just prefer to cut them back after they're cast.

Well heat your alloy better next time. Also Is that investment breakdown in the left one near the sprue? The white speck.

It wasn't the heat, I put the ring into the casting machine upside down, which meant the alloy had to flow "upstream" against the machines rotation.
That's the die, the dip**** that cut them off, cut the sprue too close.

 

[zero_zero]

What alloy is that CRob ?

 

[rkm rdt]

That's not a hole, it's a reduction coping.

 

[CatamountRob]

What alloy is that CRob ?

It's Evolution Lite.

 

[zero_zero]

It's Evolution Lite.

It makes sense why you're attempting to fix it...

Sent from my SM-G930W8 using Tapatalk

 

[charles007]

Interesting hole where sprue was cut off to short
Here's a tip if you tend to wax thicker crowns and want to save time metal finishing
My most hated job in the lab is metal finishing ... so I learned how to cast very thin casting consistently at .15 - .2 in NP and .3 with noble alloys..
On average single unit crowns, sprue mesial or distal incisal corner so you don't worry about cutting holes on facial/lingual or incisal edge like
one on these crowns. Posterior crowns, sprue mesial or distal marginal ridge where your adding wings in the build-up. Spruing in these areas will speed
up metal finishing and prevent cutting off sprues to short incisal edges and cusp tips where you normally attach sprues.
On single unit where large amounts of wax are built up, naturally you sprue thickest part of pattern.
Anyone should be able to case .3 without miscast with NP or Noble alloys if your dipped coping is .3 without thin spots and or thin areas on the margins..
If anyone is wondering how often I have miscasts... maybe 1 crown every 4 to 6 months... aprox 3 times a years = 6 units max. When I get a miscast, 25% of the
time I realize I may get a miscast once I release the casting arm... incorrect flame...
Now that I cast fewer pfms per year since I'm using zirconia, its critical I don't overlook easy correctable mistakes on my part...