2DOF Build Log Thread

Alright, well I pulled the trigger and bought the 25:1 motors as well as the driver boards and power supply. They should all be arriving sometime within the next month.
There should be a lull in my schoolwork fairly soon, and I'd like to try and get some work done on the frame if possible.
It's going to be constructed from square steel tubing, and MIG welded together (that's what I have access to at my school's machine shop).
I'm planning on using two sizes of steel, a thicker one for structurally integral parts, and a thinner one for supports and the wheel mount.

As I'm not the most experienced metalworker, would I be able to get some recommendations from you guys as to what thicknesses of steel I should be looking at? Obviously I don't want the rig to be wobbling once it's constructed, but thinner steel will be lighter and cheaper.

I'm also probably going to move away from having a full floor below my feet, and mount the pedals on a single center piece like @noorbeast has.

2mm wall thickness steel for the frame, depending on your weight and planned weight of things to put on it, maybe 25mm box mild steel square.

I weigh about 90kg, but I'd like to have people up to 100kg be able to use it with a reduced motion profile.
Also how do you guys usually treat your steel, if at all? Powder coating? Paint?

That's another good point you bring up about appropriate CTC Levers. I want to be able to mess with the length, which can be done easily enough by just drilling holes along the lever's length for mounting the arm. But I realize doing this would require either:

a) Re-mounting the arms on different points on the moving frame (one corresponding to each CTC length).
b) Having multiple arms of different lengths, or having arms of adjustable length.
c) Having the rig sit at 0 degrees with the arm and lever at a non-90 degree angle (which would definitely cause problems).

Has anyone around here done something similar? (Also what does CTC stand for? Haven't been able to guess that one yet haha)

I've updated my frame design to look prettier and use less metal.



I have easy access to everything I need to start building the frame except for a U joint (I haven't had time to shop around yet) and a seat. I can't find a good seat anywhere . I've been scanning kijiji/craigslist for literally 3 months now and people only ever want to sell them in pairs, or charge ridiculous prices for a single one. Granted I'm being fairly stingy (my budget for a seat is ideally no more than $200CAD).

I've also lined up a used GTX 970 in preparation for VR.

@Tim McGuire , nice looking frame,
As for a seat, surely you can look elsewhere...
Ebay, facbook groups that have race and or rally spares, the newspaper, local online selling sites......

Motors arrived today!


How have people gone about mounting their levers to these hollow shafts in the past?
I was thinking about putting a large bolt through the hollow shaft, and then drilling a hole in the bolt to line up with the hole in the shaft, then either putting a tight pin in there or tapping some threads and putting a screw in there.
As for the CTC itself, how do you guys keep that on the shaft without it torquing itself loose? My plan would be to either weld a nut straight onto the lever and just tighten the hell out of it, or weld the CTC to the head of the bolt.

On the downside, the welder I had access to just became a lot less available (school shop became busy, extracurricular teams get priority).

Alright, I've sorted my seat dilemna.
Probably going to go with either:
http://www.ebay.com/itm/FULLY-RECLI...ash=item2ee2d96301:g:cZwAAOSwyQtV34l4&vxp=mtr

or

http://www.ebay.com/itm/381277759978

They look very similar, this is really more of an aesthetic choice. I'm leaning towards the black one with the red stitching.

The black one looks just like my RX7 seat and I can sit in it for hours.
http://s133.photobucket.com/user/garvice/media/Seat Mounts/IMG_2825.jpg.html

300$ for shipping....wowzers.

Edit....i see your taking a trip to the boarder....good idea.....but remember those aren't full "buckets" rather recliners.

Yeah, I realized. The way I see it I'm on a very limited budget right now, so I'll take what I can get and then upgrade as time goes on if I feel that it's not immersive enough. I know a couple of friends that would want a sim rig (motion or not) that I could probably sell it to if I don't like it.

Alright, some progress today. I cut and drilled some rough mounts for the motors. My H bridge drivers also arrived, so I've wired them up along with the power supply.
I also tried getting a shaft attached to the motors. I'm using a 1/2in cap screw, which fits, but it's a very tight fit. I need a wrench to move it more than halfway in, and eventually it just starts to backdrive the motor.
My seat is also in the mail, and I'm going to a few scrapyards this weekend to look for a good U joint.



Also, what in you guys' opinion would be the best way to mount the joint to the seat frame? I was just going to bolt it on, maybe weld plates to either end of it if there aren't bolt holes to begin with (something like the pictures that were posted earlier in the thread). Also being able to slightly adjust the mount point after the fact would be a bonus (not by a whole lot, maybe 2-3 inches).

When I was trying both sizes out I couldn't readily tell. Either it's a rather sloppy fit of M12 or a really tight fit of 1/2in.
I may just file the bolts a bit on the lathe. Tighter is probably better than looser I'd imagine.

For mounting uni joint to seat frame. Basically what I have done with all my builds. Under the seat frame of 25mm box steel is a sheet of 16mm MDF screwd to it. Uni joint bolts to that at the right balance point. For me its supported 115kg driver no problem.

Perfect, thanks for the advice guys
I've got a couple of used drive shafts lined up, I'm just going to see which ones are in better condition.