X-Plane 11 6DOF motion platform

@SilentChill
That's useful info. I will give it go. I have ordered self tappers just in case.

omg just that bit of information is worth it's weight in gold!! haha. silentchill you are a legend. thankyou. Just rattle gun your M5's up and all is good

Great work

For info, I use NGEN from colorfab, it is close to PETG.
I don't use PLA

@baykah
OK thanks for the info. I am still printing with PLA mainly for testing sizing and ideas. Once I am sure all my measurements are correct I will switch over to PETG for the actuator parts. I chose PETG for the layer adhesion and strength. We use ABS at work and it is horrendous to print with on our CreatBot DX. With so many different people using the machine it is practically impossible to get it tuned properly which is why I built my own.

Once my roll of PLA is finished I doubt I will buy it again. With so many different filaments on the market it is difficult to know which is best for a particular situation.

Had some time today for test printing the lead screw ball nut adapter. Everything is a friction fit a the moment. The carbon rod sleeve it very tight so I might have to give it some room for the 3M epoxy. Edit October: it would have been better to have one part rather than three separate ones - maybe combine them with Meshmixer? This would have avoided one rod being epoxied at an angle and would make the overall part much stronger.



Edit Nov2017: I posted the Fusion 360 files for these parts in the first page of the thread. They MUST be modified as they will rub on the frame. The edge closest to the frame needs at least a 2mm clearance on either side. In other words, it needs to be at least 4mm narrower on the dimension closest to the V Slot extrusion.

...and the anti-wobble ring


Edit (Nov 2017): I am not recommending using this idea - it causes too much friction on the inside of the tube and is more of a source of problems than what it is trying to solve. See the attached photo of what the ring looks like after a few months of use.

While I am still waiting for parts and measuring and re-measuring the top frame, I thought I would have a go at the simple sleeve for the rose joint thread. This will be epoxied with 3M into the top of the carbon rod with a short section of M12 thread and a nut on either side.

Out of interest, has anyone tried using one of those POM/Delrin bearings to go at the top of the ballscrew?

The bearing should do a better job of reducing rotational friction and POM is a fairly low friction material anyway so should be pretty good at handling any vertical movement. It's also hard-wearing.

@DEADBEEF
A few projects on Xsim have tried different bearing types for the top part of the actuator including sintered bearings, igus polymer, 3D printed and linear ball bearing to name a few. I liked the idea of the longer linear bearing to support the side load on the carbon rod, coupled with the fact that it was cheap and fitted exactly. It will be noiser and it may wear the carbon rod prematurely. However, like most things what now seems to be final design becomes just another step to something better a little way down the track.

Edit: I have re-read your post and I think you now mean where the anti wobble ring goes? @wannabeaflyer2 and @baykah discussed this and came up with the idea of the 3D printed ring held at the top of the lead screw by the cir clip. They suggested it be quite loose and not rub on the inside of the tube only touching occasionally - at least that is how I read the exchange. A proper bearing might be a good idea, maybe someone else can give their opinion?

Yes, I meant the anti-wobble ring.

You'd want to use a plastic bearing to save wearing the inside of the actuator tube, but assuming you can get one which has the right inner/outer diameters and is thin enough to be secured by the circlip I'd have thought that'd be a better solution as it'll have far less rotational friction (which is where some 95% of any movement will come from).

Granted, there shouldn't be a great deal of friction there anyway, but I'd imagine that anything you can do to reduce what there is has to be a good thing.

The blocking diodes arrived yesterday and they are massive! I wanted a continuous working current of around 35A and a high reverse peak in a stud mounted package. These were the only ones I could find with a reasonable postage...but they are HUGE

The image shows it compared to an M5 nut

Edit: they may be available in different packages but the ones I received has the case as the anode which will make things difficult if I want two to share the same heatsink

I began experimenting with the position belt and pot.

The PLA filament was getting really annoying as it kept breaking into multiple bits within the bowden tube which meant 10 minutes of wasted time re-threading it and clearing the hot-end. I wouldn't recommend the Anet PLA filament, it is simply too brittle.

So time to give the eSun PETG a whirl. Very easy to work with and I don't have to heat the bed. The parts are much easier to remove from the bed once finished too. I did find, though, that if I tried any hot-end temp lower than 245C Skynet would stop the print after the first layer and report a 'thermal runaway'. I suspect the hot-end fan is working too efficiently and dropping the temp more than 10C for 60 seconds which triggers the panic stop.

The image showing the Bourns 10 turn pot frame has a M6 bolt underneath the supporting the geared pulley. I am trying to get the bolt to take most of the tension of the belt. The other two images of the top idler pulley show two variations - one 3D printed and the other cut on the laser from 3mm acrylic. I will probably go with the laser one.

Using my battery drill I ran the actuator its full length and counted how many revs the pot turned which ended up to be nearly 5 full turns. As I haven't even thought about Simtools yet I hope this can be adjusted in the settings.

Simtools does not care about your motor feedback system - it just sends the data blind. It is then up to the controller (Eg Arduino) and motor driver to turn that data into the required movement.

@SeatTime
OK thank you. I will fire up one of the Unos and load SMC3 and see what happens

@SixDegreesOfFlight
The easiest way for you to tap the openbuilds extrusion is to put your tap in a battery drill and set clutch at around 6-7.
Drive the tap forwards till clutch trips, reverse drill a couple of turns then go forwards again till you got your desired depth.
Doing it this way it only takes ~10 sec each hole.

@OZHEAT
Great tip! Thank you - I am sure it will help others too

This afternoon I thought I would pull out the angle grinder and start on the upper frame. I cut the 20x20x1.6mm steel tube into 1100mm lengths and the 50x50x4mm angle into 240mm lengths. The idea was to reduce the time to set it up when I get the chance to weld it at school with the MIG.

I also cut the M12 rod for the u-joint. The last image shows a 75x75x4mm 'washer' I got from Bunnings for $1.50. This will help spread the load of the actuator on the timber frame.

Great day today...Kev brought in the 6mm aluminium sheet and cut it up for me Good on ya Kev! I am going to finalise the drilling template tonight and begin drilling the pilot holes tomorrow. I also drilled the M12 threaded rod for the u-joints to see how that would work.

Hi @SixDegreesOfFlight nice work and pictures , very helpful stuff , got a piece of experience to pass on regarding the Universal joints and mounting plates , I used the same method on my platform as you ref Picture 20170814-1 and to a great extent it was ok but I found that the actuator could twist if the Nuts became loose , I have my platform in bits at the moment to redo this support joint part of the build ... the method works but if the joint were welded or permanently secured to each top and bottom plate it would prove to be one less area to worry about ..

as I always say guys this is not a criticism just my way of passing on what may be helpful info learnt by experience... I think @SilentChill welded his in place and I aim to follow suit This Tight arse just need to buy some material LOL ...E bay anyone cheers

@wannabeaflyer2
Thank you for the helpful advice I am trying to follow your build as closely as I can.

I feel like I have met you in person as I have watched your videos so many times and studied your photos

I will put some spot welds on the joints as you suggest. I noticed in one of your early test videos that the actuators did twist quite a bit.

As it have been some time now since you completed your build, are you planning any further improvements or changes? Cheers