Peacemakers 6dof Unicorn Build

HI, I love the mods, Just wondering if you'll be sharing it .. Also , tnx for the info on the bearings... I was scratching my head about it..

Here are my modded files, not perfect, but you can work with them, and they fit together ok
Cheers

Thank you ... I'll be trying it When i come back home this Wednesday
Cheers

Here's the new Clevis joint system i designed to replace my Rose Joints at the top of the actuators. These have like a 120 degree rang of movement so shouldn't have any issues with binding/jack knifing.



But to install them i'll need to do 2 actuators at a time.. and with the weight of the rig now its no easy task.. I have ordered a Scissor jack for my racing simulator. Sounds funny that i need a jack for my fake car lol. but hopefully this will take the weight of the top platform and allow maintenace and modifications in the future alot easier. Previously i would remove one actuator at a time ad stick a piece of wooden dowel under that point.. but with the weight of the front now with the screens its pulling up the rear actuators when i try to get the actuator back on. It gets real sketchy.. if you dropped it during that process you would destroy the rig and actuators and it would be a total mess.

Hi Peacemaker105 firstly, Thank you for sharing your project. I have started (slowly ) building the actuators.
I am now fit checking the parts.
This is where i encountered a weird issue. I'm hoping you could advise me on this one.

I have part lenghts correct based on your specs., but when i placed them together , the ballscrew doesn't reach the bearing on the top hat. I know I can mod it by placing a washer .. But probably, but I'd hope to get your opinion or maybe I missed something that may be right infront of my face .
I attached 2 pictures..
The first shows the dimensions and the second is a close up shot of the ballscrew end showing it's shortfall to the ball bearing .

Hope you could shed light to my error...

Cheers
Jaime

I modified the top mount, so I could use my 500 mm guide rods and 500 mm outer casing, so I did not have to cut and re-tap them.(I have 500 mm ballscrews)

Hope you could shed light to my error...

Hi, you could put these in the top mount to lower the bearing into the the lower bolt on piece of the top mount.
Cheers

Cheers Chris, those new mounts look interesting. How do they attach to the actuators ?

Ahh damn, I must of messed up when i measured it all. bit rough trying to measure it while its assembled lol. Thanks for raising it. I add 5mm to the bottom plate and the bearing will now fit into that piece instead. will this be enough you think?

Try this file attached: you'll only need to print the small plate obviously but I removed the bearing hole in the big one as well while I was at it. I added a special one for you with the cut out for the nuts deeper so you can still use your bolts otherwise you'll obviously need 5mm longer bolts haha.

** I should also stress that the PVC outer tube should be 2-3 mm longer than your rods just so when you tighten it down it will actually pull tight. but not too long that your ballscrew end comes out of the bearing . I have adjusted BOM to reflect this. All this stuff you keep remembering later is annoying but yeah. if you have already cut them and when its tight the tube still spins then you could just drill out the holes for the rods a couple mm longer also. Best thing to do is assemble it like @Jaime Godinez has done above and then measure the length from top to bottom seat where the tube will go and then cut a PVC tube a fraction longer


Files have been updated to have:

1. Ball nut mount (single piece instead of 2 piece design)
2. Top end plate bearing relocated to bottom half
3 Top end plate bottom half extended 5mm to better mate with ballscrew
EDIT
4. Updated ballnut mount with correct hole spacing

1. Ball nut mount (single piece instead of 2 piece design)

Hi Chris, I forgot to mention that I first printed your top mount, Ball nut mount and separate spacer to try them out and the holes for the three rods were out of line by a fair amount, so the top mount would not slide through the 3 rods at all. I used your top mount as a stencil and remade the holes in the Ball nut mount, so that they line up correctly. The ones I made are in the zip I posted if you want to check it out ? Cheers

Oh man, that's a pretty handy bit of information haha, Thanks. I edit between 4 computers. most stuff is done at work in rough form then I setup the measurements when I'm home and can measure stuff then tweak stuff on different computers. Then I end up with such a fragmented workflow I can never find the final version lol. I now use One Drive and it has helped immensely keeping the files in the one place across all computers

Updated with correct hole spacing now. Hopefully lol. FML

@Bobbitchin You got me wondering which version I printed.. lol.

Hi Chris, Thank you for the updated files, I printed the single piece Ballmount and the top endplate Bottom V2 with File Version 3.1.1 and the bearing now sirts on the ideal location. Travel now is at 490mm I have not yet tried the 12mm rods since it still has not #@% Arrived hehe....When they do I'll do another fit check using 3.2.1.. Cheers

Awesome man! just make sure you use the ball nut mount from 3.1.2 with fixed hole spacing or @Bobbitchin one he created.

@Bobbitchin where did you get your 12mm stainless from?

Hi. Firstly, I just realised I didn't thank everyone for their responses to my last post. Amazing to see multiple responses and everyone so friendly, what a community!

I haven't even got close to making the actuators yet, will be before Christmas if I'm lucky. Have been trying to figure out what feels right for the distances and positioning of the elements in the top frame. Especially because it needs to work for both me and my partner.

I think I'm ready to start designing the dimensions for the rest of the frame and pistons but I have a couple of questions that I don't think have been asked before in this forum. Apologies in advance if I've missed it but I checked all the posts this morning.

Has anyone done a complex calculation to figure out the vertical positioning of the end of the pistons? I know you want the centre of gravity to match the user's centre of gravity so you sit in, rather than on the sim. But is it important to get the vertical centre exactly right and if so does that calculation need to look at the position of the user only, or the user and rig as both will be moving as one? My design is slightly different to Peacemakers so I don't know if 400mm will still apply in my case.

At the back mount. Peacemaker's design has two pieces at 110 degrees angle to connect to the rig. As far as I can tell this should be achievable with a single piece at a shallower angle and still miss the pistons at the rear. Or am I missing something?

Also, I see 600mm ballscrews seem to now be the standard but I've seen 640 mentioned with extra bracing. Has anyone tried both (or maybe 500 and 640) and can help me understand the stability difference between the two? Trying to understand if 640 is worth trying to achieve or just too long for the 1610, especially if I want it to last.

Also, if anyone is considering the ST80s and like me were put off by the price. This seems to be getting a little better (certainly for the UK including PnP) so may be worth another look.

Thanks in advance for all the help! I really love that someone has already done most of the initial work on this meaning I can eventually have one of these rigs by following someone else's trail!

Hey mate. So..
1. Center of gravity is all personal preference really. But one thing you should consider is how much clearance you have. I have 2.4m ceilings. I have chosen to sink mine a bit to avoiding hitting the roof. but also it puts less stress on things as apposed to if you were sitting on top of the rig acting like a big lever on the hardware when doing roll moves etc.


2. the main reason the back of the tube at the rear goes up and then across to the rear is simply for ease of getting everything square (equal) All three points that mount to the actuator have to be at the same height and also need to be the same length between each other to create an equilateral triangle. Yes you could just go up on and angle with one piece of steel but if your angle is 5 degrees off then the end of your tube where you mount the actuators to will be too high or too low and also either too close or too far away. With the flat tube if I wanted to make the rig smaller then i can just cut the needed lengths of each of the three tubes to make them a perfect triangle between each other and all you need to worry about is getting them at the same height. It also takes less calculating. Easier to just make changes on the fly. If that makes sense?

3. The ability to make more compact designs maximizing stroke means we can fit longer ball screws. My new design is the same length as my old one but has over 100mm more stroke. Others use fold back style motor mounting which gives them another 100mm or so of room to play with so longer screws can be incorporated keeping the total rig height the same but with more available stroke. You don't use it all hardly ever, except flight and space sims but its good to have. If you just raced cars then you wouldn't need all that stroke.

Thanks,

Really helpful advice.

1) I might keep the arm height at the same 400mm as I believe your design is. It'll mean I'm a few inches higher but shouldn't be significantly so. I'm also on a 2.4m ceiling. Figured it should never get too close to the ceiling but do you have enough room for your setup? Do you ever get close?

2) Hadn't considered the "what if you want to change dimensions" question. Will give it some thought.

3) I'd like to get into flight sim too. Hoping Valve's next headset has AR because (Sadly it's Bradly seems to suggest so). I don't have 3x monitors, so VR works best for me, but it's hard to use a HOTAS when you can't see it . On average can you guess how much stroke is used while driving? Be interesting to know how much of the range is regularly in use. I'm also not massively constrained on space (except ceiling) so I'm thinking make it big enough that I don't want to change is later. Though that's not going well so far. Must have changed parts of the chassis design several times already.

3.1) Also figured that fold back motors would end up quite mechanically complex. I like the simplicity of your design (unless you've seen a fold back that works really well?). Am I right in presuming that

Oh and what angle does it leave your actuators at? I also have FlyPT's dimensional diagram and his has the actuators between min 49.9 and max 65.4 but I had assumed that you'd want the resting / default point to be at 45 so that it has equal motion on all planes, or have I misunderstood?

Hoping to get to finish the chassis over the next month or two so all of this is really helpful.

Hi Chris,
Just wondering if you could share where you got your C5 ballscrews... I got mine from Aliexpress... it all seems ok , but when i loop the actuator medium and slow speed .. there seems to be a vibration..
Initially, I noticed a wobble when the top end plate wasn't connected , then the wobble got tamed as i placed the top end plate and then better with the pipe on... but still not that smooth when running the actuator... it does have some vibrations especially towards the ends.... I just want to buy from another supplier to compare or rule out the issue.... Cheers

hi this side where buy Peacemaker105 ballscrew C5 Sfa1610 Ballscrew End Machined With Ballnut 250mm -2000mm Anysize Roller Screw End Machining With Single Ball Nut For Cnc - Linear Guides - AliExpress