First, just as a test if I succeed

[Edwin]

By the way I bring it to me, too just 3D CAD with and just created a caster in 3D for it to be able to create master.

It's times as one half of a roller in 1/6

[Edwin]

I am still on the accumulation of experience , but as a little I get on.

Having trouble by default and surface in rotational molding I have by the shape and size of the chain links , but I learned a lot again, I 'm working around a bit on my last microframe form. Since I will build such a form anyway also my past experience again, I can I still edit these a little and see what happens and lo and behold ....

With the reworked form I was able to immediately resolve 90 % of the remaining problems. Delay and poor surface I had not at this silicone anyway. Just filling out the form I had not yet under control.

Now only two places that I also already have almost the handle is missing .







I'll be there now try around a little and then build a new form of the current experience .

[Edwin]

Before I can build a new form with which I can implement my previous experience I will create a larger and more flexible molded frame.

This I 'm from 11.5 mm Alunminium
rods which I abfräse at the ends and in the middle , and thrust . So I can put together any bars like a log cabin .
Because the whole is built of nothing but remnants , it does not look professional, but serves its purpose. So I can now shapes in different sizes presses. The framework I have made ??it so big that it still fits well in my small oven.



After the frame is ready , I can the new form, which is slightly larger than my old frame zulies .
Thus, the silicone not verklezt with the frame I Dress him first with baking paper . Since I do not need the whole form I use old silicone molds as filling klotz



So , I offer two silicon plates and press the Master in the silicone.



As Trennmttel I dove all a with talc and as a connector I use self- cast knobs .

[ mg] ttp://up.picr.de/17396627av.jpg[/img]

So I can then rebuild the shape of three parts in one whole ..

After all silicone is processed I 'm still a chunk of aluminum to press it and screw the cover plate of the mold .
This I will still be a few minutes and put the screws again somewhat, because the silicone deforms as a viscous mass .





I put the oven on the terrace , because the smell in enclosed spaces is not exactly edifying , and make the form now by 1.5 hours.



Then I just have to cut the sprues and can use the form immediately.

[Edwin]

After the mold was allowed to cool overnight, unpacking was first time announced.



After I had the shape plastered around something . It has pushed the silicone into each hole . I had to separate the mold , which is not easy. But if you have found the beginning , it is no longer a problem .



The next step was to cut the sprues with a carving knife into the silicone. This works simply because it is quite stable and stiff.



After I had installed a couple of vent holes and the shape well dusted with talc , it went to the first casting.





But a little rework was required.
But now I have the alues ??form come from the useful links and that I can use .



The rework is almost consuming than the preparation and casting itself so you have to grind a lot , including the little hand belt sander proven once again very good.



After cutting out the Messingröchen I could start the first chain links with a 2mm spring steel bolts to connect.





What I notice when casting to my surprise is that the cold mold works best. If this is too warm arise all of a sudden again cavities and the cast is not usable.

Now I 'm going to make these chain links two new master and from two new forms that will be even better. So then the production of the chains begin for the prototypes.

[doombar]

nice work it give me a headache thinking about all of the stuff you do to make the tracks

[Edwin]

Thus , very slowly , there is next to a lot of other work here too progress .

Now I have the same time my new press frame fully utilized and created two forms in it.









And so I now have three forms for casting the tracks , which is still significantly speed things up .



So I started with the drive wheel . For this I must first find the perfect teeth and that I make from my experiences with pattern discs . The first I took over after a dimension of an original drawing and milled aluminum disc as such . On the side is for size comparison , the drive wheel of a tiger in 1 / 16th



And immediately encounter each theory and practice. An error of only 0.3 mm per tooth in the width and the toothing does not fit , although located in the Tolerance of the drawing.



I know however, to what extent I can not rely on these drawings and for what tracks ( 360mmm , or 400mm width) was thought the ring gear . There was quite small differences .
But as there is no great effort to mill a new disk and try until it fits snugly and can be applied to the Master of the drive wheel .

[Edwin]

Slightly revised to correct the pitch and the intervention in the chain.



So I can now begin the drive to draw in 3D.