RC Tanks Australia Forum

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.

I thought it was only me who stole all of the kids LEGO to make molds. I will have to show them this post to make them feel better.

What a lot of work for a single track link. Looks great though.

Cheers
Kevin

_________________

rctanksaustralia.com

Thank you Kevin,

We also intend to build a tank corresponds to the detail of Maßsabs 1/16 but 1/6. These are some works simply consuming and I have the conscious master built so as it is now also used as a template for ever.

Also, the model itself, we are treading other than the known way. The tub I will build fiberglass plastic and it is very detailed view of the shape and the technique is different than it is done in this size before.

But first, the chain has to be something, and that's still a bumpy road to get to it.

regards Edwin

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 ....

Currently here is more of a learning effect for Resincasting in multipart forms of complex parts.

Although the surface is now reasonably well when I take the members out of shape, but sometimes only thinly over the bubbles collapse immediately when I edit the parts.
So continue in the trial.
Meanwhile I injeziere the resin heated to 40 ° C with a syringe in which to vent it before just fine. Simply compress the opening and pull the piston and already all the air collects at the top and the resin is almost clear.
I also heat the mold in my little annealing prior to about 40 ° C . so that the resin can be almost water thin pressed into the mold and leave bubbles almost like water. Nevertheless, I have always more or less air to different , changing places. Oh yes breather is already there.





Now I just try out with what I can best repair defects. Apoxie is currently best suited , mainly because it after curing has a similar hardness.



So I 'll probably have to build a third form with the experiences from the first two, but this completely interpret for the resin injection from below takes place in the form of a standing up so that the air is inherently displaced upward .

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 .

Moving ahead ..........

Although the Master of resin which I am doing now are not perfect and still need a little rework, but they are used and there will be more.
For the spin cast I need 9 pieces and when I have them together I can start with this form.