that is the idea, but I'm not sure where I would go from there. To a different tooth # motor pulley?

that is the idea, but I'm not sure where I would go from there. To a different tooth # motor pulley? I'm just following what @Subsonic (Protomaker) 's guide prescribes. afaik no one else following that guide has dealt with this before. The other gimbal creaking type issues I can find plenty of troubleshooting solutions for, but not this belt issue

Nnubbins that is the idea, but I'm not sure where I would go from there. To a different t...

walmis•7/5/24, 8:08 AM

As a last ditch effort I can supply you an original Rhino pulley

Wwalmis As a last ditch effort I can supply you an original Rhino pulley

nubbinsOP•7/5/24, 8:09 AM

could you just send me a spec page/size spec for it? just to double check

HHiob Just a thought - how much current draw does the motor show when the grinding occ...

nubbinsOP•7/5/24, 8:10 AM

curr_y goes up to about 17A at max deflection, + and - in either direction, no weird behaviour

Nnubbins curr_y goes up to about 17A at max deflection, + and - in either direction, no w...

Hiob•7/5/24, 8:11 AM

then you are certainly not overstressing the Rhino.

HHiob then you are certainly not overstressing the Rhino.

nubbinsOP•7/5/24, 8:12 AM

yes, on walmis' recommendation earlier I tried turning the motor+pulley by itself and everything was smooth

nubbinsOP•7/5/24, 8:13 AM

might be gimbal related as well since I know this one is particularly bad and it's going to be rebuilt with some new parts next week. Might not be out of the question that vibrations are starting inside and traveling out to the belt via 74t pulley

Hiob•7/5/24, 8:13 AM

Sorry, if this is a dumb question, or was answered earlier - are you 100% positive that you have the right belt and pulley specs? regarding tooth profile and so on?

nubbinsOP•7/5/24, 8:13 AM

it is most significant at the belt but that makes sense

HHiob Sorry, if this is a dumb question, or was answered earlier - are you 100% positi...

nubbinsOP•7/5/24, 8:13 AM

yes, I've double checked with the guide, other people who built, and david's own rhino

nubbinsOP•7/5/24, 8:13 AM

74t pulley, motor pulley and belt spec are correct, I now have 4 motor pulleys i've mix n matched at will

Hiob•7/5/24, 8:14 AM

HTD5 on both sides?

nubbinsOP•7/5/24, 8:14 AM

yes

Hiob•7/5/24, 8:14 AM

ok! sorry - better safe than sorry

Nnubbins could you just send me a spec page/size spec for it? just to double check

walmis•7/5/24, 8:14 AM

We machine those pulleys in-house, it's based on the HTD5M spec

Wwalmis We machine those pulleys in-house, it's based on the HTD5M spec

nubbinsOP•7/5/24, 8:15 AM

15mm width, 12 tooth, 8mm bore? well, width depending on the belt of course

walmis•7/5/24, 8:15 AM

official Rhino belts are 10mm, 12T pulleys

Nnubbins 15mm width, 12 tooth, 8mm bore? well, width depending on the belt of course

Hiob•7/5/24, 8:15 AM

that's what I use.

Hiob•7/5/24, 8:16 AM

Yeah, but it shouldn't make a difference.

Hiob•7/5/24, 8:16 AM

(the width I mean - as long both gears are the same size)

walmis•7/5/24, 8:16 AM

nubbinsOP•7/5/24, 8:21 AM

@Hiob before you installed the gimbal in the enclosure, did the oval-shaped X and Y gimbal frames rotate freely and smoothly around the grip connector?

nubbinsOP•7/5/24, 8:21 AM

I think mine was overtightened. My gimbal frames barely moved at all, took a lot of force to rotate them

nubbinsOP•7/5/24, 8:22 AM

ie. the main nut, sitting all the way down in the core of the grip connector

Nnubbins @Hiob before you installed the gimbal in the enclosure, did the oval-shaped X an...

Hiob•7/5/24, 8:25 AM

Yes and no - there is a bit of a "round edge" when you try to deflect both axis at the same time. This is a geometrical thing due to how the gimbal works. Once you add an extension and grip this (very small) hump isn't there anymore (or can't be felt anymore). The inner oart of the stick connector needs o rotate slightly inside the outer part and also needs to move up and down (very very slightly) - that is what the flexible TPU part is for. A bit like a spinal disc. But without any weight and leverage, it can be felt.

Nnubbins I think mine was overtightened. My gimbal frames barely moved at all, took a lot...

Hiob•7/5/24, 8:26 AM

That your gimbal was hard to rotate isn't right though

Hiob•7/5/24, 8:26 AM

It should move easily.

Hiob•7/5/24, 8:27 AM

Perhaps the bearings weren't properly seated?

HHiob Yes and no - there is a bit of a "round edge" when you try to deflect both axis ...

nubbinsOP•7/5/24, 8:27 AM

yes, it's that second type of rotation that I mean. Was it smooth? Or did it take a lot of force
I took a picture on day 1 and X/Y frames were slightly crooked, which had me a bit concerned not because it was crooked, but because it was very hard to rotate to get aligned again

nubbinsOP•7/5/24, 8:27 AM

it did not feel like there was a bearing in there at all. More like just a screw and nut.

Hiob•7/5/24, 8:27 AM

"A lot of force" - certainly not!

nubbinsOP•7/5/24, 8:27 AM

Which I now understand looking at the subsonic guide that there are back to back flanged bearings in there

nubbinsOP•7/5/24, 8:28 AM

I suppose if it was assembled like that, then two weeks of use under high spring force might have broken something

nubbinsOP•7/5/24, 8:28 AM

since yesterday i've loosened the nut a bit, but it seems to be too late

Hiob•7/5/24, 8:28 AM

I'm thinking more of the big bearings that hold the main gimbal frames.

HHiob I'm thinking more of the big bearings that hold the main gimbal frames.

nubbinsOP•7/5/24, 8:29 AM

the big outer 6808s? hmmm they are still pretty smooth but i'll check next week

Hiob•7/5/24, 8:29 AM

If those aren't perfectly seated - aka not perpendicular to the axis of rotation, it could make the whole assemble get stuck

Hiob•7/5/24, 8:31 AM

To give you an idea - When I disassembled the gimbal to change the stick connector to my "stubby" version - after reassembling and only the 80mm grip connector as a "lever" - without belts attached, the gimbal moved freely and buttery smooth in every direction.

HHiob To give you an idea - When I disassembled the gimbal to change the stick connect...

nubbinsOP•7/5/24, 8:34 AM

with no belts attached, the gimbal has always been pretty smooth in linear x and y motion, no issues with the 6808 bearings there

nubbinsOP•7/5/24, 8:34 AM

but with circular motion it has always had some issues with internal creaking that can be felt all the way up the grip

nubbinsOP•7/5/24, 8:34 AM

probably at the beginning due to the grossly overtightened nut, maybe now due to internal damage

nubbinsOP•7/5/24, 8:35 AM

oh well........the belts weren't expensive, at least

Hiob•7/5/24, 8:38 AM

You shouldn't overthighten the central bolt that connects the two core parts. I would even argue, that the bolt doesn't need to be fixated in the outer part at all - but I haven't tried that yet.

HHiob You shouldn't overthighten the central bolt that connects the two core parts. I ...

nubbinsOP•7/5/24, 8:39 AM

i'll certainly keep that in mind for the gimbal rebuild

nubbinsOP•7/5/24, 8:39 AM

would honestly be helpful if there was a guide out there for how tight the main screws need to be

nubbinsOP•7/5/24, 8:39 AM

the main bolt/nut of grip connector and core joint, the preload screws, etc.

Hiob•7/5/24, 8:44 AM

For the free moving variant I have in mind, you would need a different outer core and bearings though. The "stock" gimbal works just fine. It is mainly the central bolt that connects the gimbal core that can't be overtightend.

nubbinsOP•7/5/24, 8:45 AM

hold on, are you using a 72T pulley? in combination with 12T motor pulley

Hiob•7/5/24, 8:45 AM

Everything else can and should be "moderately hand tight" as far as I'm concerned

Nnubbins hold on, are you using a 72T pulley? in combination with 12T motor pulley

Hiob•7/5/24, 8:45 AM

Me? Yeah the default one - 74T I think

HHiob You can also move the center point by altering the calibration values. I don't k...

kaltokri•7/5/24, 9:47 AM

Nope. I don't find anything in the configurator. I don't want a curvature in the force of the axis. I want a curvature in the value of the axis.

that is the idea, but I'm not sure where I would go from there. To a different tooth # motor pulley?

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