Cub Sandwich

Maxolini, Solidworks will be more useful for my marine craft projects, especially the mechanical on the water gokart and I had a good read of Blender, and it is very powerful, but I still don't know if it suits engineering. Something to be explored in the future. I don't feel that FreeCAD is in the position to be a solid Freeware alternative due to the developer's approach for the whole program. They need to get the various benches consistent before users would be interested in coming back with bugs and things. I would admit that I see the program as an already lost cause........still highly useful but not very serious

I am rather inclined to beat this program into a useful prototyping tool for the hobbyist by working within its set of limitations. By using it to design a number of production ready items, I have already found many of those limitations. The good part is, once the limits and bugs are found, what's left is still a highly usable environment. This project will be a good measure of its performance. Let's see if it can be used to completely design a product with all the part complexities drawn in. Keep in mind that FreeCAD is not too bad for designing a part, the difficulties arise with interactions with other parts as the model gets more complex

There is something to really like, though. Once a full product model is created in detail, it is very simple to pull off individual parts or even chop up parts to fit the working areas on the CNC or 3D printers. It's worth persisting with at a hobby level
 
Some thoughts at this stage. Eliminate the robot head look and hopefully increase performance at the same time by replacing the dual 6.5" passive radiators with a single 10" passive radiator. This will also allow more of the structure to be built with PVC foam core sandwich instead of bamboo. 10" is the max radiator size that will fit this structure, so why not build in max Sd and Xmax here. This basically eliminates one whole panel and replaces it with an engine mount. Another side benefit is that it can be placed on its side :D with the PR firing down. The SBA 10" PR with 17mm Xmax looks good. I will use that as a reference but will first run a DIY 10" PR with hexcel sandwich and butyl surrounds in a custom printed basket. I'll do this spider less but with dual roll surrounds. There is an existing thread I started on PR units and will update that thread with that drivers build. I hope knowing types of folks like @weltersys concur with this line of reasoning towards evolving this baby porch PA sub
 
That is not a reflex port. It's an extension of the pole vent with a 90 bend at the magnet. Side entry and rear active fan exhaust.
Many driver's spiders have air permeability built in, which would allow the interior air to leak through the pole vent extension, "short circuiting" a passive radiator.
You can test by blowing air through the vent, if the cone moves out and holds the air for a while, leakage shouldn't be a problem.
Eliminate the robot head look and hopefully increase performance at the same time by replacing the dual 6.5" passive radiators with a single 10" passive radiator.
That would eliminate the force cancellation the dual passive radiators offer, an important feature when making a lightweight cabinet that can easily walk around.
Another side benefit is that it can be placed on its side :D with the PR firing down. The SBA 10" PR with 17mm Xmax looks good.
An aluminum cone PR may transfer heat faster than a paper cone.

The aluminum cone SBA 10" SW26DBAC-00 PR has 400 grams Mms (14 oz, near a pound) of moving weight, about that of a small claw hammer head.
SB PR.png

Mounting a PR horizontal is generally a bad idea, gravity will defeat linear response, and with a Vas of 54L, I'd expect it would sag considerably.
The paper cone SBA 10” SB29NRX-00 passive radiator is heavier (505g Mms) and looser (66L Vas).

Have you calculated their Fb in your box volume?

Art
 
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