Dake Engine - by Pat J

[GreenTwin]

And a bit more work on the Dake base pattern.

Here is the epoxied base pattern pieces, and you can see there is some misalignment.

I epoxied the pieces together with them resting on a flat surface, upright, which misaligned the top surface.

I can deal with leveling the top surface with filler, and this will keep the bottom of the base level and flat.

 

[GreenTwin]

And here is the filled piece.

The filler looks to be big gloppy mess, but I would say 98% of the filler will get sanded off.


One method of sanding wall patch I discovered a few years ago is using sanding screens.
Sanding screens can be used with a stick-mounted sanding block, or a hand block.


The screens have an open mesh, and so they allow the dust to pass through, and allow the screen to continue cutting.

Sandpaper tends to clog with wall patch compound to some extent, but I do use a lot of sandpaper for pattern work.

Luckily this wall patch filler is not too dense.
If this were bondo, I would be sanding the rest of my life.

 

[krypto]

A very interesting engine and I appreciate the time you have already spent on making and posting the plans and documenting your build.

Just add your .STP files into a ZIP archive and then you can upload that file into this forum. It's also easier to download one container file over a multitude of separate files.

 

[GreenTwin]

Thanks krypto for the tip/trick.
I will have to remember that.

I got much of the filler sanded off of the base pattern last night.
I will have to get some new photos.

This Dake design was drawing before I got into casting metal, and so the entire design is centered around a barstock build.

If I had to do over, I would have added draft angle to some of the parts, fillets in some areas, machining allowances to the surfaces to be machined, and I would have made sure there were no overhangs that would prevent the pattern from being pulled from the sand mold.

Since I have already 3D printed these patterns, I will use filler to correct these problems.

The base is the pattern that needs most of the work.
The remaining patterns will think will be ok with minor filling work.

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