Adjustable Grinding Table - liability? (original-design) - design/advice

[lsk18271]

It's my first post here. I'd like to ask smarter and more experienced engineers to consider this design and provide feedback. I fear there may be liability for building such a table, if it fails and hurts somebody.

The assembly moves the upper portion with an electric linear actuator "Duff Norton MPD6405." It's supported with (4) vertial "leader" pins to inhibit rotation.

Inclining the table is done by a worm drive, which should block reverse rotation..

I will code an aruino to control the LA with (4) buttons, TOP, BOTTOM, MOVE UP, MOVE DOWN



My fear is that the linear actuator will fail and snap off. Bringing the table crashing down and perhaps hurting the operator. I included a picture for clarity.

PDF with functional details:

https://drive.google.com/file/d/1Iq0Vy711qJAUYirmOMqloJrPpO3oHtIM/view?usp=sharing

STL for download:

https://drive.google.com/file/d/1Q2vlXvhKEfRiaehb50X_5uMoDb5GMOJD/view?usp=sharing

Any feedback is appriciated. I'm still new to engineering but very eager to learn. Any advice will be genuinely considered. Don't be shy to critize this honestly. You could drop a PM here a reply or this email for private conversation: lsk18271@gmail.com

 

[SnTMan]

All kinds of machine tools have height adjustable tables. They never fall. I don't know what they use but it seems like a solved problem to me.

Regards,

Mike


The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[IRstuff]

Why are you only concerned about the actuator? Did you under-design it relative to all the other mechanical hardware shown in the picture?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[TheTick]

Are you selling these tables?

If not, why worry?

If so, there's lots more to worry about. Every conceivable stupid stunt done with or near the table could put you on the hook for liability. That's why you incorporate and insure.

 

[lsk18271]

Why are you only concerned about the actuator?
-Seems like the weakest point and likley the point of failure. But please consider and evaluate the entire design, but all means. Be as harsh as you need to.

Did you under-design it [Lin-Act] relative to all the other mechanical hardware shown in the picture?
-Its an off-the-shelf linear actuator, so I cannot modify it. Here's a link:

https://www.zoro.com/duff-norton-li...Rp9mGIh7HSRvoorckGEaAoi1EALw_wcB&gclsrc=aw.ds

The table is not for sale, ever, but it will be built in our shop. Its for a die sharpener without much technical knowlesge. I don't want anybody to get hurt. In the upward position the entire load rests on 0.5" diameter Lin-Act shaft. The load is ~125lbs.

From a design perspective, is there a better/safer/more reliable way to lift?
I was considering hydraulics.