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by krageon 1196 days ago
This is not about Disneyland, it is about a single dishwasher. I don't see how the scope is insurmountable for a single person when that is the subject.
1 comments

What water pump and heater do you use? do you just grab some lame thing off the shelf that's the same as existing machines (at which point, what's the point of building your own if it's just going to be the same), or do you spec out expensive custom hardware with a custom motor that has bespoke winding arrangement that manages to accomplish what you set out to do? and an induction heater that's exactly right for the expected water for? And then, what do the panels and buttons look like? Is it a Janky looking electrician's special with protruding wires and buttons that aren't suitable outside of industrial use, or do you injection mold buttons that are right?

Okay, fine, none of that adds up to Disneyland money, but we're still talking some 6-figures for this project that may never be recouped. Maybe that's an amount of money that you're able to swallow without a corporation's help. Seems a lot easier with help though.

Here's a question I have been meaning to ask many times but refrained from doing so: what makes people like you so scared of the idea of creating or modifying hardware for personal use? Why does the simple prospect of adding a movable latch to a dishwasher lead to the above hyperbole which seems to be related to the design and production of a complete dishwasher instead of simply adding a moving latch to an existing one? Add to that the comments related to the enormous size of corporation needed to undertake any design work, the prospect of houses burning down because someone did something to his dishwasher and the picture becomes clear: thou shalt not think outside the box and be scared.

Now back to the prospect of adding a moving latch to a dishwasher which will have been prepared for something like that already given the fact that another model in the same series comes equipped with one. If you have a look at the mechanism you'll probably see the latch itself being built into the door with the bar mounted on the housing of the machine. In the 'cheaper' version this bar will be a grey piece of plastic, screwed down against the machine. In the 'expensive' version the bar is a longer piece of the same gray plastic which can slide in and out, moved by a motor of some kind (most likely a rack and pinion with end stops, could also be a servomotor). To add the moving latch to the version without one you'd take the screwed-down latch and either add it to a bar which can be moved using a servomotor (which can be had for a couple of € nowadays) or make a longer version using one of the many methods available to do such. Next you´d check whether the controller provides the control signals for the latch drive in the 'cheaper' version, if it does you can simply use those. If it does not you'll have to use an existing 'ready' signal to trigger the latch, the mentioned buzzer being a good candidate. Get a cheap microcontroller, program it to drive the motor when the 'ready' signal is given and to retract the bar when it is pulled from the latch or when the door is opened past a certain point and voila, you have a self-opening dishwasher. If you count the time spent to create your own version as billable hours it is probably not worth the effort but that is the wrong way to look at it. If you count the time spent cooking your own food, riding a bike instead of a faster mode of transport, reading a book or simply looking at the clouds as billable hours those things suddenly seem to be very expensive so why bother? Well, because there is more to life than billable hours. In this case it may simply be the joy of creating something, of overcoming an artificial hurdle, of one-upping the bean counters who decided to overcharge for such a simple feature or just because you think you can.