Homing problem COREXY (H-bot)

A Former User

@Rik-Snelder said in Homing problem COREXY (H-bot):

@Stephen6309 Thanks for your quick reply. When giving the M119 code I get the following;

The motors are moving the right way, only when homing they move the other way for some reason

looks like the stops are wired in such a way as to show them as triggered when the carriage is not near an end stop, i would invert the M574 commands to get them to work, and i would remove the M574 for a Z stop (if you are only running a probe)

See Here

Manfred53

Referring to the picture. The belt routing is looking not like a corexy routing to me.

Rik Snelder

@Manfred53 It is a H-bot design, same as a coreXY just with 1 belt

A Former User

@Manfred53 said in Homing problem COREXY (H-bot):

Referring to the picture. The belt routing is looking not like a corexy routing to me.

images (2).png

fcwilt

@Rik-Snelder said in Homing problem COREXY (H-bot):

@Manfred53 It is a H-bot design, same as a coreXY just with 1 belt

Have you read why CoreXY is preferred over an HBot?

Frederick

theruttmeister

@Rik-Snelder said in Homing problem COREXY (H-bot):

@Manfred53 It is a H-bot design, same as a coreXY just with 1 belt

While the kinematic math is the same, they are otherwise sufficiently different that they should be kept distinct.

(Nice printer )

@fcwilt said in Homing problem COREXY (H-bot):

@Rik-Snelder said in Homing problem COREXY (H-bot):

@Manfred53 It is a H-bot design, same as a coreXY just with 1 belt

Have you read why CoreXY is preferred over an HBot?

Frederick

One is a Heath-Robinson contraption that adds a lot of complexity to allow less rigid frames to work acceptably.
The other is prone to racking if the base length of the bearings that support the gantry isn't long enough.

Personally, after building a single sided H-bot (which I didn't name, but maybe a T-bot? It was the most Heath-Robinson thing, I wouldn't recommend it to anyone). I rather like a single sided version of whatever the MarkForged kinematics are called.

fcwilt

@theruttmeister said in Homing problem COREXY (H-bot):

One is a Heath-Robinson contraption...

What????

I rather like a single sided version of whatever the MarkForged kinematics are called.

My most recent project is a MF style using two Y motors - it works well and racking doesn't seem to be an issue.

Frederick

Phaedrux

@Stephen6309 said in Homing problem COREXY (H-bot):

Motors moving in the wrong direction, means you need to reverse them.

Not always. When homing it can also mean that the endstops are triggered when they shouldn't be and the backwards movement is actually the backoff movement in the homing file.

theruttmeister

@fcwilt said in Homing problem COREXY (H-bot):

@theruttmeister said in Homing problem COREXY (H-bot):

One is a Heath-Robinson contraption...

What????

Or Rube Goldberg if you're an American.

I rather like a single sided version of whatever the MarkForged kinematics are called.

My most recent project is a MF style using two Y motors - it works well and racking doesn't seem to be an issue.

Frederick

(as we continue to go OT..)

Yeah, I really like it. Its a nice way to get a flying gantry, and if you do want to only use a single Y motor you can probably get away with only extending the bearings on the one side.
Going to fully single sided is mostly because I'm obtuse and like lots of cantilevers in my printers.

Back on topic for a second!

Nope, @Phaedrux beat me to it. What he said.

Rik Snelder

@Phaedrux Yea I think that that is happening in my case. It is also a really small movement only a couple of mm

Rik Snelder

Fixed the problem with the end stops! Added a '!' to invert the signal and now is everything working as intended. Thanks!

A Former User

@Rik-Snelder said in Homing problem COREXY (H-bot):

Fixed the problem with the end stops! Added a '!' to invert the signal and now is everything working as intended. Thanks!

which is what i told you to do 2 days ago...............