I'm going to make a second mould for one of my sma
- Thread starter benniejordaan
- Start date
benniejordaan
Sealiner
Made sticky.
benniejordaan
Sealiner
benniejordaan
Sealiner
Actually, the caps also make nice moulds for bulging eyes.
benniejordaan
Sealiner
chokka 123
New member
benniejordaan
Sealiner
Hi Everyone,
If you have any questions, please feel free to ask on the forum. Unfortunately, I do not respond to PM's. I would rather respond in the open forum for everyone's benefit...
Thanks
Bennie
If you have any questions, please feel free to ask on the forum. Unfortunately, I do not respond to PM's. I would rather respond in the open forum for everyone's benefit...
Thanks
Bennie
benniejordaan wrote:
Hi Bennie,
Please clarify something for me in this post. In calculating the amount of silicone needed. After your rice volume estimate you say one must add18% to the volume . (Now this is where I get confused). You say that" this is the volume of silicone required by weight" So what do I measure off? 118g or 1.18Kg or 118ml of silicone? I hope you understand what I am getting at. Thanks in anticipation
For this application (no heat) we want the mould flexible and durable. We are going to use Mould Max 30. The mix ratio is 100:10 (10% activator).
Before we start the mould, this is what you will need.
 - Mouldmax 30 (available from AMT Composites) It will come with it's catalist. If you have MM 60 it works perfect for this application too but it isn't as durable. MM 60 is 60 shore harness while MM30 is 30. Do not let them sell you Silsmooth or any other product. They do not degass.
- Silicone thinners (available from AMT)
- A kitchen scale
- Something to mix in, make sure this is a container wider in size rather than deep. It will help to expel the air.
- Mixing utensil, I use tong depressors.
Before we start. You need to add 8% by weight (not more than 10% max) of the thinners into the Mould Max 30 and let it stand for 24 hours before use.. This is very important, especially if you do not have a vacuum chamber. This will make the silicone flow better and assist in expelling air.
Try to mix it with strokes and try not to be too vigorous. You have time, dont rush it must be mixed properly with no streaks. The pot life is 45 min.
Method for calculating the volume of silicone required.
Before smearing the the box with Petrolium Jelly (Vaseline)
Mock up the mould box.
Then place some rice or dried beans or anything similar but clean in the box spreading it out evenly at the level you require it, which should be minimum 10mm above the plug.
Then place this in a measuring beaker/jug.
If it comes to 100ml add 18% and this will be the volume of silicone required by weight.
N.B. Water has an SG of 1 and Mould Max 30 has an SG of 1.18
Pour into the mould with a light but steady stream from one corner. then you can follow the flow staying just behind the edge of the flow.
Now you can sit and pop bubbles to kill the bordem or you can go have a cold beer!
Allow 24 hours to set.
Hi Bennie,
Please clarify something for me in this post. In calculating the amount of silicone needed. After your rice volume estimate you say one must add18% to the volume . (Now this is where I get confused). You say that" this is the volume of silicone required by weight" So what do I measure off? 118g or 1.18Kg or 118ml of silicone? I hope you understand what I am getting at. Thanks in anticipation
benniejordaan
Sealiner
billmatt wrote:
Basically you are measuring the volume in ml required. But you need the volume in weight because you will weigh it on a scale.
Water weighs 1kg per liter. (SG of water is 1)
The silicone is more dense than water (SG of 1.18), so if you required a liter of silicone in volume, you would add 18% to the volume to get the weight, making it 1,18 kg.
Does that clear it up?
Basically you are measuring the volume in ml required. But you need the volume in weight because you will weigh it on a scale.
Water weighs 1kg per liter. (SG of water is 1)
The silicone is more dense than water (SG of 1.18), so if you required a liter of silicone in volume, you would add 18% to the volume to get the weight, making it 1,18 kg.
Does that clear it up?
Hi Bennie,
Thanks clear as day now.
Just one other thing. I bought my "ingredients" from atm Composites including the Silicone thinners. You recommend after adding the 8% to the Base Silicone one should wait 24hrs before mixing in the catalyst; they say I can mix in the catalyst straight away. Has the saleslady misinformed me??
Thanks clear as day now.
Just one other thing. I bought my "ingredients" from atm Composites including the Silicone thinners. You recommend after adding the 8% to the Base Silicone one should wait 24hrs before mixing in the catalyst; they say I can mix in the catalyst straight away. Has the saleslady misinformed me??
benniejordaan
Sealiner
billmatt wrote:
I find the thinners isn't like a thinners you use in a paint that just dilutes it. It is more of a product that breaks the silicone down in the same way thinners will destroy a polystyrene cup turning it into a liquid. The process takes time so while you are expecting it to cure, the thinners is still busy breaking it down. If you add too much for example, it will never cure.
AMT asks me for advice from time to time...
I suspect the cure time will most probably just be longer?
I find the thinners isn't like a thinners you use in a paint that just dilutes it. It is more of a product that breaks the silicone down in the same way thinners will destroy a polystyrene cup turning it into a liquid. The process takes time so while you are expecting it to cure, the thinners is still busy breaking it down. If you add too much for example, it will never cure.
AMT asks me for advice from time to time...
I suppose its time to adapt the saying "Those who can Do: Those that can't Sell"
I wonder how many of the people who work in business like these have absolutely no hands on experience, and in the case of amt have never made a mould in their lives??
It's good to know that there are those gems'of people like yourself who can both "Do" and "Teach"
Thanks Bennie
I wonder how many of the people who work in business like these have absolutely no hands on experience, and in the case of amt have never made a mould in their lives??
It's good to know that there are those gems'of people like yourself who can both "Do" and "Teach"
Thanks Bennie
benniejordaan
Sealiner
Tope wrote:
I take it you are using Polyester resin. Not ideal because it is brittle and if you drop it on the rocks it can shatter.
You have 3 options really. The first is to use a Polyurethane which will cure to a smooth paintable surface. It isn't brittle, sands and cleanse easily and takes paint well. I would recommend F19 it has the longest pot life.
Something to note though. Get enough wire forms ready, buy a small pack and use it all up if possible. Ideally use it in an air conditioned room or at least not on a humid day, especially at the coast where it is very humid. PU will absorb moisture from atmosphere which will create bubbles. It is not agressive towards your mould.
The second option is what I prefer. I like using Epoxacast 690 from AMT. It cures to super clear very durable finish. It is very tough not brittle and sands paints easily too. It has a very long pot life (5hours) and cure time which means it degasses easily by its self but takes very long to cure. 2 days before demoulding and another 2 to cure properly. The cure time is dependent on the volume of the pour. The down side is it is aggressive towards the mould and it will destroy it over time. I have made about 50 lures in my mould and it has really only lost colour but seems fine still. I do use a mould release just to protect it somewhat. But I have multiple moulds.
The third option is a clear Polyester with a plasticizer additive, but I haven't tried it yet. Perhaps I will and revert back. That is to use a super clear Polyester resin (Polyclear 555 from AMT). NCS also sell a super clear but I can't remember their product code, it is essentially the same stuff as they supply AMT. but with a plasticizer added. You can get plasticizers from NCS. The plasticizer should make it less brittle.
I take it you are using Polyester resin. Not ideal because it is brittle and if you drop it on the rocks it can shatter.
You have 3 options really. The first is to use a Polyurethane which will cure to a smooth paintable surface. It isn't brittle, sands and cleanse easily and takes paint well. I would recommend F19 it has the longest pot life.
Something to note though. Get enough wire forms ready, buy a small pack and use it all up if possible. Ideally use it in an air conditioned room or at least not on a humid day, especially at the coast where it is very humid. PU will absorb moisture from atmosphere which will create bubbles. It is not agressive towards your mould.
The second option is what I prefer. I like using Epoxacast 690 from AMT. It cures to super clear very durable finish. It is very tough not brittle and sands paints easily too. It has a very long pot life (5hours) and cure time which means it degasses easily by its self but takes very long to cure. 2 days before demoulding and another 2 to cure properly. The cure time is dependent on the volume of the pour. The down side is it is aggressive towards the mould and it will destroy it over time. I have made about 50 lures in my mould and it has really only lost colour but seems fine still. I do use a mould release just to protect it somewhat. But I have multiple moulds.
The third option is a clear Polyester with a plasticizer additive, but I haven't tried it yet. Perhaps I will and revert back. That is to use a super clear Polyester resin (Polyclear 555 from AMT). NCS also sell a super clear but I can't remember their product code, it is essentially the same stuff as they supply AMT. but with a plasticizer added. You can get plasticizers from NCS. The plasticizer should make it less brittle.
Many thanks
I have just ordered some of this,http://www.mbfg.co.uk/polyurethane-casting-resin/easyflo_120.html
and http://www.benam.co.uk/products/plastic/feather-lite/
As you can see i am in the UK, I will put some pics up when im done, (Im not got the best of memories so might take me a while lol)
Thanks Tope
I have just ordered some of this,http://www.mbfg.co.uk/polyurethane-casting-resin/easyflo_120.html
and http://www.benam.co.uk/products/plastic/feather-lite/
As you can see i am in the UK, I will put some pics up when im done, (Im not got the best of memories so might take me a while lol)
Thanks Tope
benniejordaan
Sealiner
Tope wrote:
The Featherlite is awesome, I use it too. only 2 problems with it. It is like a sponge when it comes to absorbing moisture so you really should use that in a low humid or air conditioned room. I poured a bunch of teaser birds with it and by the time I got to the last pour, it was foaming. The second problem is sanding, it leaves pin holes that make it difficult to paint over. That said, it is great stuff because it offers you buoyancy to counter act your ballast.
A tip: Decant the tins into platic cool drink bottles. Pour volume A into a cup then immediately close the bottle after squeezing all the air out. Repeat with par b. Then mix the 2 together and pour. This way you preserve the unused product and prevent it from absorbing moisture.
BTW, the F19 is made by the same people who make the Featherlite - Smoothon.
If you have never used featherlite, you will notice when you open the tin it will appear sold. What has happened is all the micro balloons have floated to the top and the liquid is underneath. You need to use a stick or something to break it up. go crefully because it has a tenancy to come squirting back at you. Then you can make a very simple mixer for you drill to get it mixed up and break up the clots. I will post a pic. Remember to mix before peach pour because the balloons rise quite quickly.
It is just a bent up pc of 2mm SS wire. works well in a drill to break up clots.
OK, that looks good. The Easy flow only has a pot life of 2-2.5m. It seams to be a polyurethan so it is basically the same as the F19 I spoke about but much shorter pot life. See if they have one with a longer pot life. trust me, 2 min isn't a lot of time. I guarantee you it is the same stuff.
The Featherlite is awesome, I use it too. only 2 problems with it. It is like a sponge when it comes to absorbing moisture so you really should use that in a low humid or air conditioned room. I poured a bunch of teaser birds with it and by the time I got to the last pour, it was foaming. The second problem is sanding, it leaves pin holes that make it difficult to paint over. That said, it is great stuff because it offers you buoyancy to counter act your ballast.
A tip: Decant the tins into platic cool drink bottles. Pour volume A into a cup then immediately close the bottle after squeezing all the air out. Repeat with par b. Then mix the 2 together and pour. This way you preserve the unused product and prevent it from absorbing moisture.
BTW, the F19 is made by the same people who make the Featherlite - Smoothon.
If you have never used featherlite, you will notice when you open the tin it will appear sold. What has happened is all the micro balloons have floated to the top and the liquid is underneath. You need to use a stick or something to break it up. go crefully because it has a tenancy to come squirting back at you. Then you can make a very simple mixer for you drill to get it mixed up and break up the clots. I will post a pic. Remember to mix before peach pour because the balloons rise quite quickly.
It is just a bent up pc of 2mm SS wire. works well in a drill to break up clots.
