Y-axis got stuck (hard to move even manually) - please help!

[Antti N]

Hi!

I have brand new Replicator 2 (my very first touch of 3D printing so
I'm totally newbie in this) and it worked excellently for 10 small
objects but then in the middle of another print the Y-axis stopped
moving and produced very loud TRRRR sound.
I canceled the printing and it the build platform returned to normal
position.

I tried to print another object but immediately when Y tried to move,
the loud noise was heard and it didn't move at all.

I watched the gantry re-alignment video but my gantry was not
misaligned anywhere and as I couldn't move the Y at all, I could not
get the screws in sight. I then managed to get the gears to turn just
enough to get access to the right back screw and loosened it. After
that the Y-axis moved manually normally!

I loosened the right front as well and as I expected, the Y-gantry was
exactly aligned when I pulled it all the way to front as the video
instructed. I didn't loosen the left side screws as alignment was not
the problem.

Then I tightened the screws again and immediately when I tightened the
right back screw, the problem reappeared, I had to use quite a lot of
force to move the Y axis even manually and when I tried jog mode, it
got stuck and the loud noise occurred again.

When moving the Y manually, I can feel hard resistance about every
3.5cm (1.4 inch) and then I noticed it moved a bit more easily and I
tried the jog mode again. It worked fine! :o

Then I tried to print and it started fine but after few layers the Y
got stuck again and the loud noise occurred as well :(

After that the resistance feels in a bit different place than before
when moving manually (steppers disabled) but jog mode gets stuck in
about 1/3 from the front (earlier at about half way). Also in jog
mode, when I go all the way to front, I get the same loud noise when
the Y hits the front, is that normal? Shouldn't it know when the front
is reached? There is no microswitch in front but I didn't try to jog
to the very front when the device worked fine so I cannot tell if it
is different now.

There are 4 'brake points' now on the Y-axis when moving manually,
again about every 3.5 cm.

It seems to slightly help if I move the Y manually few times, it feels
to move more easily then. The resistance is very similar in each
'brake point' so I don't think this can be any lubricant problem - or
is it? The 'brake point' don't change place when moving manually, so
by that I'd say it is not lubricant problem but as I said I'm newbie
in this so some guru there probably knows better :)

I wrote ticket to support and added the new info there but nobody has
replied there yet so I thought I try here too if somebody can help me
here :)

Thank you!

Antti

[Antti N]

Really? No ideas or comments from anybody? :o

[Jetguy]

Well. the problem is mechanical. Only you have have hands on the bot.
No pics posted so it's really hard. There are hundreds of reasons why
it might bind. You have to figure it out or post pics.

Being that it happens periodically over the travel indicates likely it
is belt/pulley related, maybe alignment. You just messed with the
setscrews so you may have caused this. The belt cannot rub against the
side of the pulleys is my best advice right now with now other real
explanation from you. MBI support is not exactly going to be able to
help either without more info.

Also, the cables flex and could be rubbing into the belts or axis or
hundreds of other obvious issues. You need to look at the motion path
and determine where it's rubbing or binding. I cannot teach you
mechanics just by writing something here.

[whpthomas]

Check that all the screws the gantry hangs from are tight. Is the work area on which the Rep 2 is situates level - could be that the frame is warped somehow. Just a guess - but is sounds like the rods are out of alignment.

[Antti N]

Thanks for the reply.

On Jan 6, 4:05 pm, Jetguy <barrych...@hotmail.com> wrote:
> Well. the problem is mechanical. Only you have have hands on the bot.
> No pics posted so it's really hard. There are hundreds of reasons why
> it might bind. You have to figure it out or post pics.

Pics? There is nothing that a pic could clarify as the only way to
notice the problem is by FEEL when I move the Y manually. I also
cannot print anything as it simply won't move in Y direction so I
really can't imagine any pics that would help with this.

> Being that it happens periodically over the travel indicates likely it
> is belt/pulley related, maybe alignment. You just messed with the
> setscrews so you may have caused this.

I would never had loosened the screws if there was no problem so I
definitely did not cause this.

>The belt cannot rub against the
> side of the pulleys is my best advice right now with now other real
> explanation from you. MBI support is not exactly going to be able to
> help either without more info.

The only detail that I haven't told is that the belts are not moving
at all in jog mode when stuck, otherwise everything works normally. So
the belts are not jumping, it's the motor that just stops moving
(probably some safety feature to stop when the force gets too high to
prevent motor from breaking).

Manually the only thing that tells about the problem is that when I
move, there is quite significant resistance every 3.5cm or so. And
that after moving manually from front to back and then to front and
repeating that few times, the resistance gets less.

I did the whole gantry re-alignment and as it is not accurate (you
need to move manually to find the screw holes), I used caliper to
compare the distance from the front and it was exactly the same. Then
I leveled the plate and tried to print but again after few layers odd
sound and Y was out of position :(

> Also, the cables flex and could be rubbing into the belts or axis or
> hundreds of other obvious issues. You need to look at the motion path
> and determine where it's rubbing or binding. I cannot teach you
> mechanics just by writing something here.

Except for the resistance when moving manually, there is nothing
strange, everything LOOKS to be working fine. Belts move, gears roll
fine.

The 3.5cm distance matches quite exactly one round of the wheels and
as the only thing that causes the resistance is the stepper wheel (if
others are tightened, there is no odd resistance every 3.5cm), it
could mean that the stepper motor has some mechanical problem.

[Antti N]

Hi!

I did the alignment again but it was ok and even after the noise and Y
off course the alignment was ok.
All the screws on top of the case were a bit loose!

I tightened them, let's see now...unfortunately, that didn't help :(

Thanks anyway, it could have been that! :)

[Joseph Chiu]

Antti, it might be worth running the Y steppers without it attached and listen to see if it moves smoothly or not.

--

[Antti N]

Thanks for the tip!
I loosened the right back screw so the stepper didn't move the gantry
and used jog mode.
When using jog move step by step, no odd sounds appeared but when I
kept pushing the jog in one direction, a kind of knocking sound can be
heard on every round of the right back gantry wheel :o

I know the jog mode produces some knocking sound normally but this
varies on every round so it could be either the stepper belt (not
likely) or the stepper wheel (not likely) or the stepper motor (likely
but hopefully not).

Thanks, I'll pass this info to the support as well :)

[Dan Newman]

Any more progress on this?

If you remove the short belt from the Y stepper motor, you can see if the problem is
in the Y axis transmission system vs. the stepper motor itself. That also allows you
to run the Y motor unimpeded and see if the problem is in the stepper motor itself.

A number of folks have had bowed / non straight Y axis transmission rods running along
the back wall of their bot. Have you looked to see if yours is (1) bowed, and (2) at
some point in its rotation hitting / rubbing against something? That would cause a
tightness once per rotation. However, the rod would have to be quite bowed for that
to be the case. Either that or some strange obstruction not normally

Another long shot is that those flanges on those SDP/SI pulleys get bent and deformed
easily. I once saw a case (in another piece of machinery) where one was damaged and
bent and so once per rotation the bent part would rub against another part of the machine.

> Also in jog
> mode, when I go all the way to front, I get the same loud noise when
> the Y hits the front, is that normal?

Yes that's normal. It has no endstop there and so the firmware will gladly
allow you to jog it right into the side of the bot. The firmware doesn't
know that you have hit the front. It's up to you, the operator, to not do that.
The good news is that you won't damage the bot doing that. (At least not for
a few seconds; I don't know what will happen to the motor or electronics if you
do that for hours on end.)

> Shouldn't it know when the front is reached?

The bot has no way of knowing. Since we use a drive system which has know way
of knowing the absolute position of the extruder, the bot doesn't in general know
where the extruder is. That's what the X, Y, and Z endstops are for. The bot can
move the system into a known configuration and from there then find it's way around.
But in general you may have just turned the bot on with the extruder and platform
in any "random" position and then jogged. In that setting, the bot has no idea where
anything is and thus no way of knowing if you've hit one of the sides without an
endstop.

Note that you can buy extra endstops from Makerbot and install them. (I've done
so for purposes of testing firmwares just to make sure that folks can add extra
endstops if they want to.)

Dan

P.S. By the way, the manufacturer's spec for that pulley is a diameter of 10.82 mm which
gives a circumference of 33.99 mm so your 35 mm estimate is on the money.

[Dan Newman]

On 6 Jan 2013 , at 3:13 PM, Dan Newman wrote:

> A number of folks have had bowed / non straight Y axis transmission rods running along
> the back wall of their bot.

Sorry, I was thinking you had a Rep 1 when I wrote that. The Rep 1 had the transmission
rod running along the back (and some folks reported theirs as being bowed somewhat). On
the Rep 2, that rod is tucked away along the front. Mine doesn't seem bowed, although I
suppose it could happen. The likely thing it would rub against is the LED strip or the
wire tire for the wiring to that strip.

Dan

[Antti N]

On Jan 7, 1:13 am, Dan Newman <dan.new...@mtbaldy.us> wrote:
> Any more progress on this?

Not after my previous update, it's 7 am here and now I'm at work so I
have no access to the device :)

> If you remove the short belt from the Y stepper motor, you can see if the problem is
> in the Y axis transmission system vs. the stepper motor itself.  That also allows you
> to run the Y motor unimpeded and see if the problem is in the stepper motor itself.

Very good idea but HOW can I remove the belt? It feels to be very
tight, should I remove the stepper motor first or can I just stretch
the belt? :o Sorry if this is stupid question but I have zero
experience with this kind of mechanics :)

> A number of folks have had bowed / non straight Y axis transmission rods running along
> the back wall of their bot.  Have you looked to see if yours is (1) bowed, and (2) at
> some point in its rotation hitting / rubbing against something?  That would cause a
> tightness once per rotation.  However, the rod would have to be quite bowed for that
> to be the case.  Either that or some strange obstruction not normally

As you already noted in the next message, this does not apply to Rep2
but the front rod seems to be perfectly straight.

> Another long shot is that those flanges on those SDP/SI pulleys get bent and deformed
> easily.  I once saw a case (in another piece of machinery) where one was damaged and
> bent and so once per rotation the bent part would rub against another part of the machine.

Flanges? Sorry I don't see any flanges in the pulleys, they seem to be
solid parts. Can you please explain more what you mean? Anyway all the
pulleys seem to be in perfect shape and condition.

> > Also in jog
> > mode, when I go all the way to front, I get the same loud noise when
> > the Y hits the front, is that normal?
>
> Yes that's normal.  It has no endstop there and so the firmware will gladly
> allow you to jog it right into the side of the bot.  The firmware doesn't
> know that you have hit the front.  It's up to you, the operator, to not do that.
> The good news is that you won't damage the bot doing that.  (At least not for
> a few seconds; I don't know what will happen to the motor or electronics if you
> do that for hours on end.)

Ok, that's what I thought when I saw there was no microswitch on the
front but wanted to make sure :)

> > Shouldn't it know when the front is reached?
>
> The bot has no way of knowing.  Since we use a drive system which has know way
> of knowing the absolute position of the extruder, the bot doesn't in general know
> where the extruder is.  That's what the X, Y, and Z endstops are for.  The bot can
> move the system into a known configuration and from there then find it's way around.
> But in general you may have just turned the bot on with the extruder and platform
> in any "random" position and then jogged.  In that setting, the bot has no idea where
> anything is and thus no way of knowing if you've hit one of the sides without an
> endstop.

Ah yes of course, the home position is where the system knows exactly
where it is, otherwise it has no clue (unless of course it has moved
the extruder itself).

> Note that you can buy extra endstops from Makerbot and install them.  (I've done
> so for purposes of testing firmwares just to make sure that folks can add extra
> endstops if they want to.)

Hmm...do you think there is need for those, I mean SHOULD I add extra
endstops? :)
The front and left ends won't be problem as the system is built so
that the extruder does not go even very near those ends other than
with jog mode so is there really need for those extras? What's the
benefit?

> P.S. By the way, the manufacturer's spec for that pulley is a diameter of 10.82 mm which
> gives a circumference of 33.99 mm so your 35 mm estimate is on the money.

Ok, that 35mm was difficult to measure accurately as the resistance
changes smoothly, not by step so it can very well be 34mm as well :)
That's good starting point so this problem HAS to have something to do
with some pulley or the stepper motor itself.

Thank you very much for your ideas, problem not solved yet but on the
right direction :)

Antti

[Antti N]

I will check that too but the strange thing is that before the problem
occurred, the device worked perfectly, even the nut and bolt printed
and worked perfectly. Then just in the middle of one print (doing
about 5cm diameter raft) it simply got stuck and after that it has not
worked correctly.

======
One thing I noticed is that the belt directly from the stepper motor
to the gantry seems to go very close to stepper motor side but the
case is on the way so I cannot see exactly if there is any gap. But if
I can remove that belt then I can use jog mode to check if the sound
changes when running the motor alone.

So I hope you (or someone else) can tell me HOW I CAN SAFELY REMOVE
THE STEPPER MOTOR BELT before I go back home i.e. in 7 hours :D
======

I will of course re-read the manual for that too but I don't remember
seeing that info there but of course I can be wrong as I was not
searching for that when I read the manual :)

Thanks again!

Antti

[Dan Newman]

> Very good idea but HOW can I remove the belt? It feels to be very
> tight, should I remove the stepper motor first or can I just stretch
> the belt? :o Sorry if this is stupid question but I have zero
> experience with this kind of mechanics :)

You need to remove the stepper motor. There may be a better technique,
but that's my first reaction when I look at the printer. However, you may
first want to wait and hear what MBI support suggests.

>> Another long shot is that those flanges on those SDP/SI pulleys get bent and deformed
>> easily. I once saw a case (in another piece of machinery) where one was damaged and
>> bent and so once per rotation the bent part would rub against another part of the machine.
>
> Flanges? Sorry I don't see any flanges in the pulleys, they seem to be
> solid parts. Can you please explain more what you mean? Anyway all the
> pulleys seem to be in perfect shape and condition.

The pulley has 17 teeth around it's circumference. The teeth engage the
mating teeth on the belt. To keep the belt from rolling off the pulley
teeth as the pulley turns, there is a flange on each end of the pulley.
If the flange is bent inwards (towards the pulley teeth), then you may
feel a problem twice per revolution: once when the bent part hits a belt
section winding on to the pulley and then a second time as it hits the
belt section as it comes off the pulley. You don't have that -- you don't
feel two interferences per rev. If a flange is bent outwards AND is
hitting or rubbing against something else in the bot, then you feel
that interference once per revolution. Of course, it could be something
else such as the stepper motor.

> Hmm...do you think there is need for those, I mean SHOULD I add extra
> endstops? :)

No, there's no need for them IMO. However, some people do add them.
In some cases they likely do so for good cause, but what those causes
are, I don't know. I just know that I've been asked from time to
time if Sailfish supports extra endstops.

Dan

[Antti N]

Hi!

WOW you reply fast! Thank you! :)

On Jan 7, 8:08 am, Dan Newman <dan.new...@mtbaldy.us> wrote:
> > Very good idea but HOW can I remove the belt?
>

> You need to remove the stepper motor.  There may be a better technique,
> but that's my first reaction when I look at the printer.   However, you may
> first want to wait and hear what MBI support suggests.

Ok, I'll check the groups if someone has any ideas on that (that they
have received from the MBI) or wait until the support replies (because
of the time difference, it will be evening for me before the reply is
even possible to arrive).
Are there any problems with removing the stepper motor? Only loosen
and take off the screws that hold the motor (2 if I remember
correctly) or is there some precautions to do first? Or something else
I should know before removing the motor?

I couldn't find any info on this on the makerbot site and there is no
wiki anymore. Any other resources than this forum?

> The pulley has 17 teeth around it's circumference.  The teeth engage the
> mating teeth on the belt.  To keep the belt from rolling off the pulley
> teeth as the pulley turns, there is a flange on each end of the pulley.

> If a flange is bent outwards AND is
> hitting or rubbing against something else in the bot, then you feel
> that interference once per revolution.  Of course, it could be something
> else such as the stepper motor.

Ok now I know exactly what you meant and I didn't notice any bending
on those but I'll re-check them again when I'll get home.

> > Hmm...do you think there is need for those, I mean SHOULD I add extra
> > endstops? :)
>
> No, there's no need for them IMO.  However, some people do add them.
> In some cases they likely do so for good cause, but what those causes
> are, I don't know.  I just know that I've been asked from time to
> time if Sailfish supports extra endstops.

Ok, then I won't do that at least yet, maybe later :)

Thanks again!

Antti

[Dan Newman]

> Are there any problems with removing the stepper motor?

No, not really. Just don't lose the screws.

> Only loosen
> and take off the screws that hold the motor (2 if I remember
> correctly) or is there some precautions to do first?

Turn the bot off first. Maybe unplug it from the mains if you want
to be extra careful. Then you can try manually moving the Y axis
and see if it has the same problem. You can also turn the motor
by hand and see if you feel a particularly bad spot. Don't be surprised
if the LCD display glows a little: when you manually turn the stepper
motor, you generate electricity. (On the Rep 1, you can see the LCD
display illuminate. I've not paid attention to what happens on the
Rep 2.) And, it's okay to jog the stepper motor when it's not
connected to the belt.

> I couldn't find any info on this on the makerbot site and there is no
> wiki anymore. Any other resources than this forum?

There is http://support.makerbot.com/forums which you can try searching.

Dan

[Antti N]

On Jan 7, 8:52 am, Dan Newman <dan.new...@mtbaldy.us> wrote:
> > Are there any problems withremovingthe stepper motor?

>
> No, not really.  Just don't lose the screws.

ok :)

> Turn the bot off first.  Maybe unplug it from the mains if you want
> to be extra careful.  Then you can try manually moving the Y axis
> and see if it has the same problem.

I have used the disable steppers command for that, is that different
from when the power is off? Though I have tried that power off as
well, I think.

>You can also turn the motor
> by hand and see if you feel a particularly bad spot.

I tried briefly earlier but it was very hard to turn it by hand when
the belts were in place so I stopped as I was not sure if that can
cause some harm but I'll check that again to make sure. Should I be
able to turn the motor by hand when power off and belts in place or
only when the belt is removed?

And how to adjust the stepper belt tension after putting the motor
back? I read the X belt tension can be adjusted with some screws but
the Y motor is other way so how I can adjust that tension? I might see
that obvious when I'll get back home and see the device but if you
have any ideas, please let me know :)

>Don't be surprised
> if the LCD display glows a little: when you manually turn the stepper
> motor, you generate electricity.

Oh, ok, yes of course, motor works as generator too :)

> And, it's okay to jog the stepper motor when it's not
> connected to thebelt.

Ok good.

> > I couldn't find any info on this on the makerbot site and there is no
> > wiki anymore. Any other resources than this forum?
>
> There is http://support.makerbot.com/forums which you can try searching.

Yes that I checked too, nothing about removing the belt but it may be
useful for something else.

One more thing, the gantry alignment procedure:
It is very difficult to make sure the gantry stays aligned when trying
to find the screws so I did it a bit differently but in my opinion,
more accurate way:
-loosen the 4 screws
-tighten left back and right back screws (those are not mechanically
connected so those are not significant for the alignment)
-move the Y gantry so that it is about 5-6cm from the front (so that
you can access the front screws)
-tighten the left front screw
-move the Y gantry so that the right front screw is visible
-use caliper to take the measure from the RIGHT (between the surfaces
of the case and the Y gantry that get together when moving the gantry
all the way front) in this case it was 52.5mm.
-move the LEFT side (without moving right side) so that the left
measure matches the right measure
-tighten the right front screw
That way there is no need to move the gantry after the measurement and
so it is as accurate as caliper can be :)

Actually, there is no need to loosen other screws except the right
front as the back wheels roll independently. Do you agree with this
method?
It is impossible to do the alignment accurately as the video shows
because each screw is at different position so there is the risk that
you move the sides unevenly.

The alignment has not been problem in my case but just in case I need
to do that in the future, is this method ok? To me it is much easier
and accurate than the video method but I am not 100% sure if the
result is as good anyway.

Thanks again!

Antti

[Dan Newman]

> I have used the disable steppers command for that, is that different
> from when the power is off?

THe "disable steppers" turns off the power to the stepper motors but
leaves power on elsewhere including +5V to the endstops via wiring
in the harnesses inside the bot. It won't harm you, but you also
don't want to slip somehow and short something.

>> You can also turn the motor
>> by hand and see if you feel a particularly bad spot.
>
> I tried briefly earlier but it was very hard to turn it by hand

If the motor was "enabled", then it would indeed be very hard to turn.
If it was not enabled (was disabled) and/or power was turned off, then
it shouldn't be very hard to turn *normally*. However, something
is not normal with your bot.

> Should I be
> able to turn the motor by hand when power off and belts in place or
> only when the belt is removed?

All depends upon what the problem is. If the problem is in the mechanical
power transmission system, then forcing things to turn may damage something
in that system or may damage something which is impinging on the mechanical
power transmission system. If the problem is inside the stepper motor, well
then the stepper motor is likely broken already.

> And how to adjust the stepper belt tension after putting the motor
> back?

On that very short belt, when you put the motor back the tension should
be set automatically *unless* you find that the mount is adjustable.
In that case, MBI would know. (And recall that I've suggested you just
wait to hear from MBI.)

> One more thing, the gantry alignment procedure:
> It is very difficult to make sure the gantry stays aligned when trying
> to find the screws so I did it a bit differently but in my opinion,
> more accurate way:

I've not had to do a gantry alignment on my Rep 2. On my Rep 1, I just
slide the belt a tooth or two.

Dan

[Antti N]

Hi!

> On that very short belt, when you put the motor back the tension should
> be set automatically *unless* you find that the mount is adjustable.
> In that case, MBI would know.  (And recall that I've suggested you just
> wait to hear from MBI.)

This was actually not a problem after all as the motor mount has
screws around the motor in direction that cannot change the tension.
So I removed the screws and...see my next message for results :)

[Antti N]

Now I think I found the cause!

The motor pulley seems to be too 'deep' and so the belt touches the
motor side AND also the gantry holder!
That can be caused only the way that the motor pulley has loose screw
and so it has moved deeper to the axle (the axle end is visible about
3mm).
I also noticed that the motor is very hot, I need to wait until I try
to remove it, it does not burn but it feels unpleasantly hot.

SOLVED!!! :)

I removed the stepper motor (not from the case wall but from the motor
holder) and noticed that the motor was very hot. The pulley was
rubbing against the motor and there was scratches on both the motor
and the pulley. Then I loosened the pulley screw and moved it to exact
position so that the upper pulley was at same distance from the case
than the motor pulley. Then I tightened the pulley screws REALLY tight
and re-assembled the motor.

Manually there feels no varying resistance and the gantry moves
smoothly. Now it is printing the nut and bolt again (good test for
accuracy) and it's almost done and the result looks absolutely
perfect :)

Ok, printing complete, result is PERFECT, the nut fits the bolt
perfectly and moves from top to bottom totally smoothly!

Thank you very much (especially Dan) for all great ideas and help, I
now know A LOT more about this device and your ideas helped me to go
to right direction to find and solve the problem!

Have a nice day!

Antti

[Dan Newman]

On 7 Jan 2013 , at 9:00 AM, Antti N wrote:

> Now I think I found the cause!

Great news. Someone else posted to this list about having that
pulley too close to the Y stepper motor. However, I figured that
if that was your case, it would likely be rubbing/causing strain
more often than once per revolution.

Dan

[Gary Crowell]

Has MakerBot really never heard of Loctite?

--
----------------------------------------------
Gary A. Crowell Sr., P.E., CID+

Linkedin  Elance  KE7FIZ

[Antti N]

> Great news.  Someone else posted to this list about having that
> pulley too close to the Y stepper motor.  However, I figured that
> if that was your case, it would likely be rubbing/causing strain
> more often than once per revolution.

Yes but the 'secret' in that is that the pulley has the thin slot that
is part of the tightening mechanism and THAT slot was 'knocking'
against the motor every revolution so causing the sound and feel :)
And the reason why the feeling got softer when manually moved the
gantry few times was that it made the scratches on both pulley and
motor a bit deeper and so for a while allowed them to rub more
smoothly :)

Actually now every symptom makes sense :)

The result is really perfect now, actually better than before the
problem occurred as the nut and bolt has absolutely no varying
resistance when turning the nut and the surfaces are totally clean, no
even smallest errors anywhere :O

I will try the high resolution today, any tips or ideas for that? I
thought I'd use Makerware (latest beta) for that but do you think I
should try ReplicatorG for hires?

I read earlier that slicing can be long process but so far it has been
only few seconds (mostly I cannot even notice the progress bar) even
on a quite complicated object. Well, I have pretty fast computer -
Intel Core i7-3960X CPU @ 3.30GHz (6-core) with 32GB RAM, Win7
Ultimate/64).
And of course hires can be different story.

Oh and one more thing, not related to this topic either but I would
like to make objects inside objects, like hollow ball with holes and
then another similar ball inside it. Is that possible with Rep 2 and
if so, what is the best method?
I think I would try it by making the inner ball JUST above the bottom
of the outer ball and make some thin supports (not using makerware
supports) inside the outer ball to hold the inner ball and still be
able to quite easily cut the supports afterwards. Or should the
support go through one of the outer ball holes to the build plate?
Is that proper way to do it or do you have some better ideas? :)

[Antti N]

that would be too permanent, in case the pulley got damaged, you
needed to replace the whole motor. Plus that motor pulley would be the
only palce where it even could be used as other pulleys need to be
adjustable.


On Jan 7, 8:32 pm, Gary Crowell <garyacrowel...@gmail.com> wrote:
> Has MakerBot *really* never heard of Loctite?

>
> On Mon, Jan 7, 2013 at 11:00 AM, Dan Newman <dan.new...@mtbaldy.us> wrote:
>
> > On 7 Jan 2013 , at 9:00 AM, Antti N wrote:
>
> > > Now I think I found the cause!
>
> > Great news.  Someone else posted to this list about having that
> > pulley too close to the Y stepper motor.  However, I figured that
> > if that was your case, it would likely be rubbing/causing strain
> > more often than once per revolution.
>
> > Dan
>
> --
> ----------------------------------------------
> Gary A. Crowell Sr., P.E., CID+

> Linkedin <http://www.linkedin.com/in/garyacrowellsr>
> Elance<http://www.linkedin.com/redirect?url=http%3A%2F%2Fgaryacrowellsr%2Eel...>
>   KE7FIZ <http://www.arrl.org>

[Gary Crowell]

I use Loctite Blue 242 removable.

On Mon, Jan 7, 2013 at 11:21 PM, Antti N <atn...@gmail.com> wrote:

that would be too permanent, in case the pulley got damaged, you
needed to replace the whole motor. Plus that motor pulley would be the
only palce where it even could be used as other pulleys need to be
adjustable.


On Jan 7, 8:32 pm, Gary Crowell <garyacrowel...@gmail.com> wrote:
> Has MakerBot *really* never heard of Loctite?

>

----------------------------------------------
Gary A. Crowell Sr., P.E., CID+

Linkedin  Elance  KE7FIZ

[Antti N]

Oh, I didn't know about that, thanks for the tip :)
So far I am happy with hand-tightened screws but I'll keep that in
mind for future and other purposes.

Thanks!

Antti

On Jan 9, 10:18 am, Gary Crowell <garyacrowel...@gmail.com> wrote:
> I use Loctite Blue 242

> removable<http://www.amazon.com/Loctite-37418-Medium-Strength-Threadlocker/dp/B...>
> .

[arthur schmitt]

Hi Anti, 

I'm having a very similar problem.

I've attached a few pictures. Does that look like the problem you had? 

Thanks, 

Arthur