Not really a CNC, but 3+ axis machine

Hopefully this is (can) be as simple as I initially planned, and even built non-permanently.

I am a decent woodworker, I mean that I count that as my top maker skill, but I tinker around with a lot. If I don’t understand it, I want to. I am also disabled an in a power wheelchair.

What I’d like to do is build a semi permanent shower chair that moves in 3 axes. I envision(ed) this thing as basically a bench that could change elevation and also the seat would move me on the X-axis from just outside the shower into the middle of the shower (at least). As I started thinking about it again recently I realized that moving toward and away from the shower head would be beneficial as well.

My problem is that I don’t know much at all about electricity or even motors. I built a lightweight version from three slow actuators to give to my handyman to make a real one and he couldn’t help. I just had two six inch actuators for height (so I am always going down when I transfer), an 18 inch actuator for X travel, they had two switches all together, 2 12 V wheelchair batteries waterproofed underneath going to an XLR wheelchair battery charger port. The seat was a boat seat sitting on plywood mounted over/in between a pair of those SS rods that bearings fit over. So if was pulled on that by the larger actuator.

I am hoping y’all can help me with better motor selections.

From trying to make things easier for myself around the house and also just playing I have accumulated quite a few things that could help.

I have a Shapeoko XXL that I build a couple of years ago, a DOF Reality H3(a gaming chair used for car racing powered by three what look like wheelchair motors. Those two things are just to show that I have some experience with this type of thing. A ‘gate closer’ which in spite of it being the lightest model is just a large actuator (maybe 30”) with a 500 pound capacity when pushing sideways i.e. closing a gate with a control board that accepts wireless key fobs and many other peripherals. A powerful standing desk that I can take apart but the actuators are also 30 inches which seems a bit long except for the Y travel., But then again I don’t really understand how to hook them up well for X travel unless it is going straight in and out. Lots of aluminum extrusion and endless wood. Power wheelchairs with motors and some with actuators. Two pieces of 5 foot long gate track and the casters that ride on them. I don’t even on the gate with these two separate gate things. I was thinking these could keel the bench straight and one wheelchair motor with wheel could bed mounted in the bottom middle and ride on skateboard grip tape glued to the floor. Possibly having a separate foot section with the same set up. The X axis actuator isn’t a good solution. The verticals work but having little experience makes me think there is an easier way that could be simpler. I was imagining a wheelchair motor with a cog instead of a wheel gowing up a “ladder“. I don’t know anything about this, I already sad.

I really know even less about controlling these things other than DPDT switch. I would like for them somehow to work together. I don’t know the code for an old wheelchair but the joystick could work?.

Wheelchair motors are 24 volt.

Any help with motor selection (all parts. In the past, i have just used what I had. I am super willing to pay for new stuff for this though), driver stuff etc. would be really, really helpful.

Want to post pictures of that model to go alongside your description? It’s an interesting problem!

(You can post pictures either by using the button with the arrow pointing up in the message composer box, or by dragging and dropping pictures into the message you are composing.)

While I’m sure electric wheelchairs are designed to run in the rain, I’d personally be worried about putting electronics (even DC) in the shower, and would want my electronics to live outside the shower and use only mechanical linkages into the shower.

And the Standing desk. I believe it has two Acme screws, with nuts that can be used as the Z axis, and the top frame, if it’s tubing maybe as the chair mount frame… You know a guy that can weld I hope?

How heavy are you? Are you ambulatory? How big is your shower and bathroom? Are you wanting to move the whole bench/chair or have it stationary and the chair move atop the frame? Have you thought about a Hoyer lift?

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Thanks for the replies and sorry about the time to get back to you. I guess Joe ate a diagram would help. I will try to do that later today I shouldn’t take too long. I don’t have the original one because the handyman took that to make it waterproof and could not figure it out even though he had a full scale model just not sturdy. It’s some thing I can build, I just didn’t want to and I wanted him to be in charge of the waterproofing.

I definitely understand the issue with the waterproofing and what we had decided is that he felt like he could not legally put AC power in there, so no transformer from AC to DC. But he felt fine putting batteries in a box that was waterproofed. Nothing would be in direct contact with the shower and of course it would have to get a little wet and would be in an environment that had lots of humidity. The actuators I was using were rated to an IP rating that suggested this would be OK. The wheelchair motors can definitely run like that if they are not getting wet. I have heard they can run underwater, I doubt this, but I have seen a picture of an elderly woman driving through the floodwaters of Katrina with the water almost up to the top of her seat.

I am thinking of this as a large CNC basically in the simplest way, but with a movable foot platform that may be could be elevated as well it could get very complicated, or I could leave it as simple as possible. My husband thought is just waterproofing a wheelchair. That would be the easiest if it was my daily driver. For the past few years I have used a wheelchair to transfer to that I have just left in the shower. All the electronics were taken out so it is just a bitch effectively. I expected the seat to get very moldy very quickly but it doesn’t have any mildew smell or mold or anything. So if I could waterproof the batteries out of the control box Then it seems like that might work. Not as fancy as building a new one but I am just looking for an easier way to take a shower. I will post pictures of the initial thing that work outside of the shower that I used to give the handyman, and then I will post pictures of what I am thinking but need y’all‘s help on. Anyway, thanks for reading all this

Oh, I am currently about 160 pounds. The initial idea was to have the boat seat to move a top the frame. The frame did not move forward or backwards which means I can’t get in the best position for a shower. I assume none of y’all stand in the same spot every time.
There are definitely bigger issues here though. So The 6 inch actuators vertically moved a bench, for the lack of a better word, up and down so that I was always transferring down. Then there was an 18 inch actuator that moved it in and out of the shower, just the seat. So the bitch is stationary except for vertical movement and the sea moved horizontally with an 18 inch actuator that would move it about halfway into the shower and move it to about the seats with outside of the shower. Everything else was stationary. I have heard of a Hoyer lift but I cannot place it right now. It seems like some thing else that is another step that would make this take longer and be more demanding. I’m not ambulatory and cannot stand up but I have upper body strength, so it is relatively easy to move from one chair horizontally to another. The issue is if the second chair is above the first chair I am coming out of. If you put your hands all the way down to your side and push you could only go up about half a match. If there are rails or things that I can get much higher. Maybe this will all make more sense with the diagram

Building on the Hoyer idea can this be mounted from the ceiling if it was reinforced?
The idea is to enter the waterproof sling when it is outside the shower and then pull [or power] the sling into the shower. The sling runs in/out up/down on a track in the ceiling.

  • Electrics can be kept above the water line and potentially out of the shower area.
  • You could have only 2 axes; horizontal and vertical.
  • It could be manually powered with a pulley system
  • Could have a pulley system whose motors are outside the shower.
  • Could have two shower heads; one in front and one in back.

I built my dad an open shower about ten tears ago. He drove his “cart” in it every day. It was a three wheel Mobility cart. We put a plastic chair on it so the foam seat wouldn’t get wet. He would transfer to his regular wheel chair and change the seat on his cart, goto take a shower. then when he was dried off he would blow dry his cart and change it back to a seat…