Alloy Pot Temp

[RIMLESS]

Anyone know what the pot temp should be set at for 117 alloy? Is 125 too high?

[CuriousCat]

I think it's labeled 117 because that's the pot temp.

[DragonLensmanWV]

Yes, but the temp will drop in the throat passage to the block. I have my 117 alloy set at 125. If you can lower it without it solidifying in the throat, do so.

[RIMLESS]

Thanks, that what we set the pot at and it seems to be flowing great.

[WFruit]

The last alloy blocker I used had two independent heating elements, one for the actual "pot" that we kept at 118~120, and one for the "throat" that we kept at 123~125.

[RIMLESS]

The last alloy blocker I used had two independent heating elements, one for the actual "pot" that we kept at 118~120, and one for the "throat" that we kept at 123~125.

Was that a semi tech blocker? That's what we're using. How do you measure the throat temp?

[DragonLensmanWV]

That's what I use. Stick a digital thermometer down the hole where the alloy comes out to get your throat temp. You can adjust it on the right side, through the smaller hole.

[WFruit]

You have to understand, the last time I used an Alloy blocker was about 13 years ago.... I'll see if I can find a picture of it.

And here it is:

There are two thermostat dials on the front, one for pot, one for throat.

[RIMLESS]

Thanks for all the help. Now does anyone know where I can score some 117 Alloy for a fair price?

[Chris Ryser]

Lens blocking alloys are used to attach optical lens
blanks to surfacing blocks for grinding the required optical
prescription into the lens blank.
The advantage of using low melting temperature alloys is
that they conform to any lens confi guration, are easy to
use, and recyclable.
Plastic lenses:
The low melting temperature alloy used for
plastic lenses is Indalloy
® 117, with a melting temperature
of 117°F. Due to the popularity of plastic lens, it is the
most common alloy for lens blocking and can also be used
for glass lenses. This is because plastic lenses will warp
if a higher temperature alloy is used. In many facilities
Indalloy 117 is used exclusively to prevent the accidental
use of a higher temperature alloy on plastic lenses.
Glass lenses:
In addition to Indalloy 117, Indalloy 158, with
a melting temperature of 158°F, is another commonly used
alloy. However, Indalloy 158 has a better bond strength and
is used only for glass lenses.
Two other alloys that can be used for glass lenses are
Indalloy 19 and 136. Indalloy 19 has a melting point of
140° F and is both lead and cadmium free. Indalloy 136
has a melting point of 136°F and is cadmium free. These..................................................

www.indium.com


also:

http://store.dacvision.com/DacEdge/p...ar,714,119.htm