Bafang Ultra frame build - Steel

[marek7805]

want to weld it to my steel frame also...did you give up the project?

[mike425]

I Stumbled across this thread, does anyone still have the cad files for the G510? I made one by hand but a drawing would be very useful! Also does anyone have a drawing for the M600 mount?

Regards

[ErikYoung89]

I'll see if I can find them. I went through some big life changes in the past 4 months and abandoned the project.

Edit: I think I just messaged them to you.

[eBikeaholic]

Hey guys... I'm in a similar spot with my build. I'm hoping to find a machine shop to CNC a mount, any chance you could PM me the MM G510 mount CAD file? ... I'm also using Fusion 360.

Thanks!

[steelycycles]

Awesome. I haven't (yet) found a workshop I can access machinery like that.. so if you do have some luck let me know and it might be that I'll pay you for one?

[steelycycles]

Thanks - just received it! I'll have a play and let you know how I get on. Big help.

[ErikYoung89]

The past couple weeks I've been trying to figure out a good way to accurately bend 1/8 inch high tensile steel.

I really don't want to use a mild steel for this mount as I'll be welding it to a cheap HT frame.

I managed to talk some chairpeople at the makerspace to order a brake for the shop press that would be rated for 3/8s.

I'm pretty excited to turn a lot of perfectly good steel into scrap!!!

[ErikYoung89]

Hey steely, I sent you the dxf that another forum user sent me. I opened it in QCAD, screenshotted it and imported it into Fusion 360 as a canvas. After tracing it, I cut a few side parts out of aluminum using a CNC plasma cutter at the local makerspace.

[ErikYoung89]

No clue. They hate bespoke frame builders, maybe?

I finally tested my Ultra kit. Brought it to work and hooked it up to a high voltage powersupply.

Exciting!!!

[steelycycles]

Hey up. I'll be watching this thread with interest - I'm planning a build with the Ultra motor too - be interested to see your progress with the mount. I also work in steel and have got the same problem of having to fabricate something. It seems weird that they would make one in aluminium for frame builders - when most framebuilders work in steel.. any ideas why?

[ncmired]

After shredding up my jeans twice in the last few months (which REALLY SUCKS when it happens), I'm also eyeing that chain guard - or, well, some sort of guard anyway. For now I'm velcro strapping - the same kind I use to hogtie the shark battery down.

[ErikYoung89]

I think I'm going to build a steel mount like the one used in the Rodriguez build in the second post of this thread.

Only I'll use angle bends instead of curved. Won't be as pretty, but much easier to build and weld.

[ErikYoung89]

Used a plasma cutter to cut a dummy part out of aluminum.

[ErikYoung89]

These are all options that I'll explore for my steel motor mount. I honestly just ordered the aluminum mount to use as a template! If I ever do weld it onto an aluminum frame I would just need to slightly expand either the front or back holes.

As always, your post was very helpful!

[commuter ebikes]

Got my Ultra kit in today. It seems to be all there but the mount just doesn't quite fit the motor.

More specifically the tollerances are off just enough such that I can have either the back and middle bolts inserted or the front and middle bolts, but not all three. It's not a matter of the holes being wide enough but rather their placement.

The easy solution is just to drill slightly wider holes one either the front or rear bolt holes on the mount to accommodate the tolerance.

You could (1) minimize the number of locations where you will expand the bolt holes, and (2) enlarge the holes in as small of increments as the selection of drill bits manufactured will allow (appears to be 1/128" increments, worth buying on the net and waiting for the drill bits). Then, when you just get it, stop there, even if it is a really tight fit. Rigidity is a good thing.

In addition to this, you could also consider using washers (bolt shank length permitting) in order to maximize the clamping surface area for the bolt, and use blue Loctite on the threads of the bolts. This is my favorite: https://www.parktool.com/product/med...adlocker-tlr-1

I often upgrade my bolts, washers and nuts to Grade 8 (US) or Grade 12.9 (metric), readily available on eBay in any size and style that you would ever need.