X-Plane 11 6DOF motion platform

Small update today. I finished the bottom frame and cut the Openbuild extrusions. Now that I have the 3D printer back in action with the Vertex bed mat, I began some test prints based on @baykah. The bottom motor plate with 20% infill took nearly four hours so I might have to consider other options such as going back to my hard wood idea.

Edit: have a look in the 3D forum Anet A8 my experience where I review the Vertex mat



Edit2 (Nov 2017): Using SMC3 utility I was using the square wave option going around to each actuator in turn...and I found a weak spot Definitely have to use hardwood for the actuator mount points. Chipboard/particleboard is simply not good enough.

So I made a rookie mistake.

The motor technical drawing shows the shaft diameter as [apparently] 14mm so I went ahead and ordered the plum shaft couplings based on this dimension. However, this morning while I was taking measurements for the hole spacings to model the 3D parts I decided to get out the vernier caliper and actually measure the shaft diameter. Damn. The technical drawing shows the motor from a side view and the dimension given is not the diameter but the distance across the shaft between the flat machined areas where the grub screws go. The actual diameter is 17mm. This is an odd size so the number of choices for the plum shaft couplers is limited ... and expensive

Hi mate I did a quick search and these aren't to bad at 2 for £12 " Bore3 to 17mm"

https://www.aliexpress.com/item/2pc...lgo_pvid=82ed6523-4714-4623-83e0-f72f285dfc2f

@SilentChill
Thank you, that's very kind of you to have a look for me and send the link

I need a Plum coupling to fit from the end of the machined lead screw to the motor shaft (10mm x 17mm) When it says "bore2" what does that mean?

Doh! I scrolled down and they explain that they can't enter 12.7mm so they use Bore2. Will this be too big for the shaft though?

Ahh sorry I just thought you needed 16mm x 17mm.

Yes that would be too big

@SilentChill
Thanks Craig. After a few hours of searching through AliExpress and eBay I finally found these. That size was really hard to find. Some listings which sold lots of different combinations didn't have the sizes in their descriptions so the only option was to read through each one

I hope you ordered 8 x 17mm couplings, not the 10 x 17mm ones you linked.
There is a driven end where your bearing block is and you need to connect motor to that end.

Another way would be to use a a m8x10 shoulder bolt, screwed in to motor shaft.
Use stud adhesive and maybe pin it.
Then cut head off, that will leave you with a 10mm shaft to which you can use a 8x10mm coupling.

@OZHEAT
OK. Thanks for that. I did measure the machined end of the lead screw and it has the thread for the lock nut and then a 10mm shaft for the coupler. It is definitely 10mm because I checked with the caliper. I noticed that when I got the lead screws from AliExpress that some sellers had different machined ends and some without any machining at all. Thanks for your help though

@OZHEAT
I have now had more time to read your advice.

It was a good idea to use the already threaded motor shaft to bring the diameter down. I didn't think of that. I wonder though if the larger sized couplers can handle more torque? e.g. 8 x 10mm vs 10 x 17mm. The size of the polyurethane sleeve is much bigger as the diameter of the coupler increases it seems. The one I ordered has a working torque of 10N and a peak max of 20N. I hope that is enough

Today I cut out some of the lower actuator plates from 3mm acrylic on the Eplilog Zing laser to check hole alignments and begin getting a feel of how the lower part of the actuator fits together. Once I have confirmed the measurements I can begin the process of 3D printing them.

Three of the 24V @30A power supplies arrived today. I hooked one up to see how much the output voltage could be adjusted using the on-board pot: 23.51V - 27.21V (unloaded). This means that they can be set up to overcome the forward drop of the blocking diode. Good news

The thread tapper arrived today so I can at least cut the M5 threads into the Openbuild extrusions.

Edit: this is going to take WAY to long around 3-5 mins per hole x 48 I have now ordered 12g metal self tappers. I will put the link on page one.

Hey mate good read, looks like you're well on your way.
I am building similar specs to you and have ordered 24v 450w 4500rpm motion dynamics motors. This was so i could get away with using 2x32 sabertooths.. do you really think you need the 2x60? Because damn i would have gone 12v lol.

What did you end up doing for the top of the actuators? Ive got 25/21 carbon rods and have 12mm threaded bushes with 20mm OD coming and was gonna use 3m dp420ns to secure them. Im more worried about securing it to the ballscrew but not sure on its dimensions so will wait until it arrives to figure that one out.
Was going to cut out aluminium for the end plates but if 3d printing works good enough i might have to look into that.. what filament will you use?
Anyway good luck and I'll keep following while i wait for my deliveries to arrive

@Peacemaker105
Time will tell if the Sabertooth 2x60 is too over engineered. I suspect it will be. The 2x32 can deliver 32A continuous with almost double that for short peaks. The major downside of the 2x60 is the need for a battery whereas the 2x32 uses resistors for the regenerating current. This is what @wannabeaflyer2 used. As you have 24V then you are going to need at LEAST two batteries if you follow @SilentChill. I wasn't comfortable putting all my power supplies in parallel, so that meant six 12V@33Ah batteries which I got for $65 each new. Lucky for me they were in Melb so I did a local pickup. As you will have read I will be making three modules of two power supplies/batteries. Obviously all this has some steep cost implications not to mention safety, space and weight. For your consideration, @SilentChill has successfully used six power supplies in parallel and one large used car battery - which he got from a wrecker for $20! He switched from 2x32 to 2x60 but he was using 12V motors with higher current. His rig has worked fine for 8+ months like this and I take his advice very seriously.

Now as for your second question - 3D printing. @baykah has shown that it does work, however, the downside is the time it takes to print the thicker parts such as the very bottom plate connecting the u-joint to the timber frame and the one supporting the lower lead screw bearing and V Slot extrusions. Last weekend I did a trial print of this plate from one of @baykah pieces from his SketchUp design at 20% in-fill and it took the best part of 4 hours. I suspect it might take the best part of a day at 60-80% in-fill. On Monday I started to scope out the cost of 6mm aluminium plate and what tools I would need cut holes especially for the 80mm fan on top of my motors. I asked a colleague at work how he would cut a hole of that size. During that conversation he said he happened to have a 2400x1200mm sheet of 6mm plate that I could have - he would even cut it for me OMG (good on you Kev!). Last night I ordered more screws for this new configuration. Much happier with this direction. I am using the laser cutter at school to verify my hole centres and produce drilling templates from 3mm acrylic.

Finally, for the bearing on the top plate I am going to use the standard linear bearing from AliExpress. This is what @baykah used. They are noisier though. Have a look on the first page of this thread for the link/cost. The carbon rod fits perfectly into this bearing. I find it hard to justify the cost of the Igus bearings that others have luckily got for free.

All the best with your build.

@Peacemaker105
For the connection between the ball screw and the carbon rod most builders have gone for a 3D printed circular sleeve that incorporates some kind of anti-rotation. Apart from @SilentChill who used carbon fiber tape, others have used glue or screws. I am going to use the 3M epoxy (see link on page 1) which I am confident will be man enough for the task.

My study is beginning to look like a store room

Today my goal is to try out the SAAS seat on my simulator to see how things fit with regard to the top frame. The problem I might have is the upper frame metal bar at a right angle directly in front of me interfering with the helicopter cyclic (joystick between the legs). The other consideration is whether I have enough space for my left arm to reach down for the collective (looks like a hand brake) at seat height. This needs to be solved before I weld (still need to learn that skill!) to the top frame.

Yeah the reason i went with 24v was because the 12v systems were overloading the 2x32 but i wanted to avoid batteries, although if they don't keep up i'll be up for 3 new sabertooths and 2 batteries.. its going to be a bit of a gamble but i think they'll handle.
Ive got the same bearing as you it sounds LM25uu.. yeah i'll put up with the noise for now haha, have emailed Igus enquiring about a couple, see what i can work.

Good score with the Ally plate, I was going to buy a cnc and add it to the cost of the project but to get one to do 6mm aluminium is 5 times the price.. 3d printing is easy for designing and cheap but timely yes.. although mine is use to running 24/7 stints. prob just get creative with hand tools or use mild steel and use plasma cutter. I see 3dhubs do cnc quoting now so might dummy a design up and 3d print for fitment then see how much to get them cnc'd.

Don't need to tap into the extrusion just screw the M5 bolts straight in they will tap themselves I just used my drill driver with a 8mm bit in the end and screwed straight in no problems

I am going to use PETG because it is harder than PLA but easier to work than ABS - not much difference in price either.