I have a silicone mold I'm using to make wax copies for use in the lost wax process.
When I pour wax into the silicone mold, I end up (sometimes more, sometimes less) with lots of very small air bubbles that cling to the surface of the silicone mold...and in tight areas will even create a 'void'.
Does anyone have any suggestions on how to eliminate air bubbles in the wax while it is still liquid and sitting in the silicone mold ?
Thanks a ton !
Russ
( BTW, any new information on WM@BE III ? )
Wax copies....itty bitty (small and numerous) air bubbles.
Moderator: Brad Walker
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Terry Craig
try to let the wax cool a bit b4 pouring into the mold. sounds like you might be introducing bubbles from boiling or water in the wax. another option is to jiggle the mold when it is full o'wax to get out the bubbles. another tought os pour in a bito'wax roll the mold around to cover the whole inside then fill it up.
terry
terry
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rskrishnan
- Posts: 14
- Joined: Mon Aug 18, 2003 6:59 pm
Re: Wax copies....itty bitty (small and numerous) air bubble
Hello Russ,coolntn wrote:I have a silicone mold I'm using to make wax copies for use in the lost wax process.
When I pour wax into the silicone mold, I end up (sometimes more, sometimes less) with lots of very small air bubbles that cling to the surface of the silicone mold...and in tight areas will even create a 'void'.
Does anyone have any suggestions on how to eliminate air bubbles in the wax while it is still liquid and sitting in the silicone mold ?
Thanks a ton !
Russ
( BTW, any new information on WM@BE III ? )
Your problem seems to be one of the following -
1. Water mixed with the wax - so either "dry" it out or just throw the wax away!
2. Wax is very hot - so it continues to "boil" while in the mould
3. Perhaps you've mixed micro-crystalline (dirty brown wax) with some beeswax ?? This mix has always resulted in bubbles for me since beeswax is easier to melt than micro-cry. Even though the waxes are "compatible" i.e. they don't separate or any such thing, they still behave as separate chemical entities within the wax body - so the bees wax "boils" within the micro and you have micro bubbles. The micro voids seems to point here but you did not say what wax you were using.
If you do have to mix waxes (to soften the micro) then heat the two waxes separately and mix before you pour. Seems to mitigate bubbles.
Personally I don't mind a "bubbly" wax - I can fix the surface problems and there's less crap to melt out !!
Krishnan
--
If I could I would, but I can't so I won't.
Still I love to cast glass ....
If I could I would, but I can't so I won't.
Still I love to cast glass ....
Okay...interesting bubble info...
Krishnan,
I had done that before...the last item you pointed out...mixing beeswax and microcrystalline. I will do as suggested, throw out the old and try virgin microcrystalline.
Is there any other wax you can suggest using ? I know there are a ton of varities out there.
Thanks a ton,
Russ
I had done that before...the last item you pointed out...mixing beeswax and microcrystalline. I will do as suggested, throw out the old and try virgin microcrystalline.
Is there any other wax you can suggest using ? I know there are a ton of varities out there.
Thanks a ton,
Russ
Hi Russ
At last something I can help with. I have been working with waxes as a dental technician for +- 30 yrs not to mention different impression materials. From what I can understand about your problem is the following
1 Do not pour your wax too hot
2 Always melt your wax in a double boiler to avoid forming bubbles in the wax and so as to not burn out any of the constituents
Go to one of your nearest dental labs and ask them for scrap Dental wax Tell them that you are looking for setup wax used for setting up dentures.
This is the best wax to use as it is made from all natural waxes and not petroleum based waxes
3 Before pouring your wax rinse your silicon mould out with a weak mixture of detergent and water to break the surface tension of the silicon which hates a liquid and tries to chase it away.
4 Blow dry with a hairdryer after pouring your debubblizer out and warm the mould up in hot water keeping the inside DRY
pour your wax in when you see the first hardening around the edge of the wax The wax starts to go white.
This is the rule of thumb for pouring wax masters at the correct temp.
Pour as though you are pouring your first beer of the day and you don't want a head to form. i.e. slowly down the edge of the mould and when you straghten your mould up tap gently to dislodge any bubbles. The trick is to have your mould hot enough to avoid the first layer hitting the walls of the mould setting and trapping bubbles as once this happens you can tap all day and you will not get rid of the bubbles
Happy wax work Regards
Ian
P.S. the wax is called Kemdent Toughened no 4 if you have to buy from a dental supply house
At last something I can help with. I have been working with waxes as a dental technician for +- 30 yrs not to mention different impression materials. From what I can understand about your problem is the following
1 Do not pour your wax too hot
2 Always melt your wax in a double boiler to avoid forming bubbles in the wax and so as to not burn out any of the constituents
Go to one of your nearest dental labs and ask them for scrap Dental wax Tell them that you are looking for setup wax used for setting up dentures.
This is the best wax to use as it is made from all natural waxes and not petroleum based waxes
3 Before pouring your wax rinse your silicon mould out with a weak mixture of detergent and water to break the surface tension of the silicon which hates a liquid and tries to chase it away.
4 Blow dry with a hairdryer after pouring your debubblizer out and warm the mould up in hot water keeping the inside DRY
pour your wax in when you see the first hardening around the edge of the wax The wax starts to go white.
This is the rule of thumb for pouring wax masters at the correct temp.
Pour as though you are pouring your first beer of the day and you don't want a head to form. i.e. slowly down the edge of the mould and when you straghten your mould up tap gently to dislodge any bubbles. The trick is to have your mould hot enough to avoid the first layer hitting the walls of the mould setting and trapping bubbles as once this happens you can tap all day and you will not get rid of the bubbles
Happy wax work Regards
Ian
P.S. the wax is called Kemdent Toughened no 4 if you have to buy from a dental supply house
Hi Russ
Afew things I forgot to mention.
dental wax is formulated to be carved without dragging so is ideal for all those projects you may want to start from scratch.
You can make plaster of paris moulds to pour your own blocks for carving, just make sure the plaster is soaked in hot water and pour the water out so that it looks dry i.e.no drops of water inside.
To make sheet wax dip a the bottom of a cold bottle into the melted wax to get the width you need and the thickness is determined by the no of times you dip. Eight times = about 3mm
When you have cast your wax model you can polish it when it is cold using cotton wool under running cold water. This removes any minute scratches and facets from the surface of the wax that might trap air when you invest your wax model for burning out
Melt out your wax from the invested mould either with boiling water poured into the mould or placing it upside down over a steam source and take out any residue with a syringe fillied with boiling water. I use a piece of hose attached to the spout of a large kettle with a piece of quarter inch copper tube as a nozzle. Flatten the end of the copper tube to make a small aperture. this also gives a bit of pressure like a mini steam cleaner.
all I can think of at the moment
Regards
Ian
Afew things I forgot to mention.
dental wax is formulated to be carved without dragging so is ideal for all those projects you may want to start from scratch.
You can make plaster of paris moulds to pour your own blocks for carving, just make sure the plaster is soaked in hot water and pour the water out so that it looks dry i.e.no drops of water inside.
To make sheet wax dip a the bottom of a cold bottle into the melted wax to get the width you need and the thickness is determined by the no of times you dip. Eight times = about 3mm
When you have cast your wax model you can polish it when it is cold using cotton wool under running cold water. This removes any minute scratches and facets from the surface of the wax that might trap air when you invest your wax model for burning out
Melt out your wax from the invested mould either with boiling water poured into the mould or placing it upside down over a steam source and take out any residue with a syringe fillied with boiling water. I use a piece of hose attached to the spout of a large kettle with a piece of quarter inch copper tube as a nozzle. Flatten the end of the copper tube to make a small aperture. this also gives a bit of pressure like a mini steam cleaner.
all I can think of at the moment
Regards
Ian
Thanks for all replying
Thanks for all that replied to my wax issue and bubbles.
Gained a lot of insight.
I took several suggestions and combined them...I just poured a wax cast last night and let cool. Very few bubbles ! This is what I did...
1. I used striclty microcrystalline wax (although not virgin, recycled)...I did not mix with bees or any other type of wax.
2. I heated up the silicone mold in the kiln at about 160 degrees F for about 20 minutes.
3. I sprayed a light coat of release agent on the silicone mold.
4. Poured melted wax ('keep warm' temp of my crock pot) very slowly.
This seemed to greatly diminish any bubbles. I'm going to try a couple other things...but this seemed to work great. I will try another pour tonight to see if I can duplicate the good results.
Russ
Gained a lot of insight.
I took several suggestions and combined them...I just poured a wax cast last night and let cool. Very few bubbles ! This is what I did...
1. I used striclty microcrystalline wax (although not virgin, recycled)...I did not mix with bees or any other type of wax.
2. I heated up the silicone mold in the kiln at about 160 degrees F for about 20 minutes.
3. I sprayed a light coat of release agent on the silicone mold.
4. Poured melted wax ('keep warm' temp of my crock pot) very slowly.
This seemed to greatly diminish any bubbles. I'm going to try a couple other things...but this seemed to work great. I will try another pour tonight to see if I can duplicate the good results.
Russ