Presses: Big lentil types

[Krysia@No98]

I have been working this afternoon with my new 40mm lentil/coin press.  I'm finding it cracks a lot. 

I warm the bead press it and it cracks!?!

Is there some additional trick like keeping the press warm that I should know about?

Thank you

[Kaz]

The bead needs to be warmer - if the middle has gone cool it may crack while you're working it. Just reheat thoroughly and then repress.
Kazx

[ScarletLeonard]

I keep my presses on my torch top marver, keeps the press nice and warm too, but as Kaz said it is probably the middle of the bead getting to cool.

[sarah t]

use a larger mandrel it maintains the heat better in the bigger beads at the core and then like the others say heat control is the key

[awrylemming]

I keep my big presses on top of the kiln unless I'm using striking glasses and want it to be cold.  It lessens the thermal shock to the glass and I rarely lose a bead since I started doing this.

[Krysia@No98]

I have been using a thicker mandrel, a 2.4, I'm usually on a 1.6.

Interestingly the cracks have been appearing at 11 and 1

I have been getting worried that heating the bead too much before it's pressed will make it lose it's definition and I have only been repeatedly pressing because they have already started to loses that definition before hand....

Thank you I shall try these tips on wednesday or thursday when I next get to the torch 

[Helen G]

I have a 45mm or 50mm (can't remember which) slim lentil press and it is a b****r to use, I've had the same cracking/splitting issues and like Kaz said it is when the glass is a little too cool so rather than squish it splits

I usually press gently several times on both sides 

[Krysia@No98]

yup pressing more then once.

I'm fine with other presses.  Only have cracking issues with the Bavarian flat eggs and the flat heart but that's because they are so very thin...

It goes, load glass, make very melty, press, get part shape, make melty but not too much again, press again, now should be about the right shape, make almost melty for tidy up presses, do this a few times, all fine, so get to decorating...

If the bead needs to be pressed again then the cracking occurs, by this time the press has cooled down.

[Dragonfire Glass]

you need to keep warming it whilst decorating ...

[Krysia@No98]

I am keeping it too warm while decorating which is why I go back to press it, in the mean time the press has got cold and that is what cracks the bead!!

[Pat from Canvey]

I have never pre-warmed a press. The action of pressing warms it up anyway.

[sarah t]

and if they get too warm the pins can stick ...i generally only use the top on the final couple of presses ,i shape and tweek using only the bottom of the press 

[flame n fuse]

My pressed lentils often crack if they have transparent over an opaque core, but not the 11 and 1 pattern.

[Krysia@No98]

and if they get too warm the pins can stick ...i generally only use the top on the final couple of presses ,i shape and tweek using only the bottom of the press 

still cracks when I only use half of it    But I know what you mean about the sticking pins.

Think I am going to need to go back to the thursday principle of slowly when it comes to re heating after the decorating.

If it does the 11 and 1 cracks I shall see if I can get a picture.  It interesting that you should mention incasing I had put a naff glass on the inside and put the 'nice' glass over the top.

[Krysia@No98]

okey dokey, I put the press on the torch top marver and there were a lot less cracking issues.  However because I get stupidly close I nearly caught myself in the face a few times with a hot pin