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Now the link should now be ready for molding, but I've probably made ​​it a bit early to release gas into the furnace. There is again a small tear came I still have to fix, but this is no great action.



The casting I will first try without centrifugal casting. By the size of the limb, it might work. If it does not work then I can make the form required for centrifugal casting another master.

My mold is just barely big enough ....

And on it goes with the insanity as someone has so beautifully expressed , but also with method.

First, the mold lining with baking paper . Thus, the silicone stays nice and separated from the mold .



I do not use silicone 2 K , but sheet goods which is then cured with heat .. This is to be processed as clay and later gets their properties .



And so do I embed the link in the form .





It is then simply baked in a small oven . However, you should do it because of the sweet smell preferably outdoors.



And so you can now see and edit the Vulcanized form .







However, I 've seen here that the chain I can not pour with this type form . I'll need through the rather complicated chain link at least a three-part form, and it is too cumbersome as the number of individual members to pour clean, but one learns from it.

That's why I still cast a first attempt , although there was no usable member.





The necessary ventilation channels I no longer appropriate . In addition one must try several fonts, but I can see how the elements fit together later and I 'm satisfied.



So used any more time on this method and for my centrifugal casting machine built ready because I can make this in a cast with a minimum of 6 members and certainly have no problems with the finer Struck doors.





And here is the test run. Everything works and I can control 0-1800 rpm .

Now I 'm just happy to have made ​​it my master completely of aluminum . It is stable and does not damage the molding . So I can use it just as often .

Nothing the defiance I will now use a three-part silicone mold for resin chemical molding to create .
This has several reasons .

The silicones used for centrifugal casting are substantially stiff and with only two parts to the chain links without damaging the shape hardly see . So I can try it but quite simply as the best division of the form might look like.
I need at least 6 master for a meaningful spin cast .
Resin has been found within limits suitable for pressing and baking my shape silicone and I can just pour limbs.

So I now have faith in the first half mold from plasticine and Lego bricks . However, there remains a lot of work as the master to embed into the putty so that a usable surface and clean dividing lines arise .



Once the link is embedded clean I have to pull up only the edge with Lego blocks and can pour the mold with something harder quality silicone mold .
For the other parts I'm thinking to use something soft silicone .



I let the first be at least until tomorrow now .

If I include the so together it is around 40 hours I needed for the link ....

But with the silicone mold for Resincasting it also goes further. Today I poured the second of three moldings. Once the basic shape was the most time consuming it is now a little easier and faster with each part.

Hi Edwin
But very very interesting.
I like to watch.

Michal

Thank you Michal.....

After I first had to order and wait for the new shape silicone delivery let us go on .

I reassembled the Lego box and installed Eifll ventilation funnel made ​​out of plasticine and then poured the previously two -part form .





The new silicone is slightly faster , smoother and it looks like it did not like the other problems with the plasticine. The surface remains smooth and unlike the previous unimpressed.



So I still do not like the shape , but I did not expected that I do it right the first time . Nevertheless, I now pour even a link from resin . Let's see how it is . But I will put the stock bars back first into the mold.





Now I have to wait until tomorrow first again .

Now I've made a few casts with the form .











I am satisfied with the form, as it is not yet , mainly because of this it would be greatly weaken a fundamental error produced by a small offset to the joints and too much air is still there. But that is not bad because I get to die here first as a lesson to see the knowledge for the very expensive spin cast .

So I have begun today from this experience to build a new shape.

Back in the Lego box , because the simple and works well . So I am learning slowly better to model with clay which also makes getting to be fun .







For casting the mold I have found a better now suitable for silicone and so the Grundbassis is ready.



After the silicone is fixed you can have the difference between the old form and the new left , see right.



Also the division of the form I get a little modify the three fittings to better separate . Here, the modeling for the second portion .

The new shape is finished ..... and works much better .



Here you can already see that it fits better and more exactly to each other .







The small vent holes I made with a drill. With a very high rotating works quite well and I have exactly the right places .



And so I'll have the same cast and a new chain link.





After the resin was cured sufficiently the big moment came .





It still has bubbles , but this time it's useful with a little reworking.



On the next cast I'll try it with an injection, but one learns ....

Resinform the Third ...

After I so do not get the bubble theme with the second form in the handle , I build from the experiences of the first two of a new form again . This I will only provided with a single vent and a filling .
But first, back to embed the link in plasticine. To get this even particularly smooth the putty beflamme I still very carefully with a small gas burner.



For mixing of silicone and Reesin I use a fine balance.



After the silicone is networked I cut the surface tension raised by the edges with scissors so that the mold can lie flat .
so it looks from form to form better.





I share the top again with modeling clay and paint the silicone release agent before casting with a . For this I use a simple oil for cooking . But there is not any oil used . But you can easily find out by the silicone smeared with a thin film of oil. If it pulls evenly and thinly over the surface , you can use the oil , if it looks like water on a fresh car polish it will not work .



So I 'll do it then with the third molding.



In my annealing , curing works much faster and better.



And so the new shape still looks as a block and then separated .





Now in the forms I make no vent in the casting sprue and more . These later I drill with a drill to the areas where they are needed.

Since I was approached because of the reuse of syringes.
I'll harden the resin is pull the plunger out and press the resin with a wire from the syringe. It is almost as often reusable.







Even the thought of minimum weight of the tank I'll probably have to move by 5 to 10kg for top . I have today once weighed a chain link zamak and finished at about 55g the pair of chains will probably come to about 10kg . For this, the chain through their high weight but should run well .