Pulley Problems

25 views
Skip to first unread message

Jesse Robinson

unread,
Aug 10, 2012, 7:35:01 PM8/10/12
to sect...@googlegroups.com
Got my ShapeOko today, yay! Ran in to problems right away, No!

Anyways, got these steppers on eBay, I didn't look, I thought they had setscrews, they do not. I used the only pulley puller I could find at work, which could only grab on the top part because its big, and we had to push it into a screw into the shaft because its threaded point was too big for the motor, and ended up breaking the ridge. I tried cutting a new ridge, but nothing seems to work. I'm thinking I might have to cut these things out  Suggestions?  Does Sector have anything that might help me?  Maybe a smaller pulley puller that can get under the bottom ridge?  The shaft is 5mm for reference.

Pulley1Small.jpg
Pulley3Small.jpg

jesse ransom

unread,
Aug 11, 2012, 6:07:43 AM8/11/12
to sect...@googlegroups.com
if its press fit cut it off, but there might be a pin that you can drill out that would solve the problem. the pin will look like a set screw. also you could make a rig that will fit into the press and press it out but cutting it is easier.

Jesse Robinson

unread,
Aug 11, 2012, 9:19:56 AM8/11/12
to sect...@googlegroups.com
Just thoroughly looked around the whole pulley and there is no such pin :-(

Also, I've had several suggestions just to crush it, as in the picture it looks like plastic.  It is indeed metal.

Joe Kerman

unread,
Aug 11, 2012, 12:48:12 PM8/11/12
to sect...@googlegroups.com
especially since you have (I assume) a few to do, I would find a hunk of scrap steel around the shop and make a jig for the 50 ton press

if the pulley feels like its made from lesser material than the stepper shaft (a lot of them are alu, or crappy pot metal) you could also try a nut-splitter, or just mashing it in the press and see if it wont split.

--
You received this message because you are subscribed to the Google Groups "Sector67 Public" group.
To view this discussion on the web visit https://groups.google.com/d/msg/sector67/-/6psIhuGkVUwJ.

To post to this group, send email to sect...@googlegroups.com.
To unsubscribe from this group, send email to sector67+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/sector67?hl=en.

Chris Meyer

unread,
Aug 11, 2012, 1:20:37 PM8/11/12
to sect...@googlegroups.com
Yeah, I would just make a plate that you can slip below them and a press (or carefully applied hammer and punch) to knock it off with.  Plate just looks like a letter "c", set it on the top of a vise and hit the shaft.   Hoping that the shaft moves before the plate you made bends. If that has a set screw anywhere it's not going to move until you drill it out, the other solution is to use an abrasive dremel wheel and slit it until it slides free, being careful to miss the shaft.  Those pulleys are sometime sintered and otherwise really brittle, so a puller doesn't usually work very well unless you get a good bite.


Chris

Todd Bakken

unread,
Aug 11, 2012, 2:32:08 PM8/11/12
to sect...@googlegroups.com
A good trick if you just want it off is to us a fresnel cut off wheel and split almost to the shaft and then insert a straight blade screw driver into the cut and twist to split it off the shaft
The cut is parallel to the axis of the shaft. No Promises...
image.jpeg



On Aug 10, 2012, at 6:35 PM, Jesse Robinson <cole...@gmail.com> wrote:

Got my ShapeOko today, yay! Ran in to problems right away, No!

Anyways, got these steppers on eBay, I didn't look, I thought they had setscrews, they do not. I used the only pulley puller I could find at work, which could only grab on the top part because its big, and we had to push it into a screw into the shaft because its threaded point was too big for the motor, and ended up breaking the ridge. I tried cutting a new ridge, but nothing seems to work. I'm thinking I might have to cut these things out  Suggestions?  Does Sector have anything that might help me?  Maybe a smaller pulley puller that can get under the bottom ridge?  The shaft is 5mm for reference.

--
You received this message because you are subscribed to the Google Groups "Sector67 Public" group.
To view this discussion on the web visit https://groups.google.com/d/msg/sector67/-/mRkvkn-FWHQJ.

To post to this group, send email to sect...@googlegroups.com.
To unsubscribe from this group, send email to sector67+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/sector67?hl=en.
<Pulley1Small.jpg>
<Pulley3Small.jpg>

Jesse Robinson

unread,
Aug 11, 2012, 6:35:43 PM8/11/12
to sect...@googlegroups.com
Picked up a tungsten carbide tip and dremelled it down to the shaft, then flipped it over and started on the other side and it eventually came loose.  I think the motor might be slightly damaged now though, it is slightly harder to turn in one direction than the other.  Its fine when I have the coupler and threaded rod on, but by hand it isn't super easy.


On Friday, August 10, 2012 6:35:01 PM UTC-5, Jesse Robinson wrote:

jesse

unread,
Aug 11, 2012, 6:56:06 PM8/11/12
to sect...@googlegroups.com
you could bring it over to sector the shaft might be bent but it shouldnt be.
--
You received this message because you are subscribed to the Google Groups "Sector67 Public" group.
To view this discussion on the web visit https://groups.google.com/d/msg/sector67/-/oQacjmHvaf4J.

Jesse Robinson

unread,
Aug 11, 2012, 11:21:57 PM8/11/12
to sect...@googlegroups.com
It seems to have loosened up over time of spinning it, which I had to do to get this nut on for the Z-Axis.  Attached is a pic of where I am at currently.  I am stuck again because the makerslide has been fighting me the whole way.  There was a problem with the center to center distance on batch 1 and though I am in batch 2, this appears to be an issue still.  I really don't want to bore out both my X end plates to get this to fit and introduce the slop that comes with it.  I posted on the forums because the last guy that had this problem they sent him new makerslide.  I bored out the 3 motor mounts to get the makerslide attached, but the Z-Axis doesn't matter as the coupler allows for some slop and the two Y axis plates I have replacements (upgrades) coming.   I wish I could get further tonight, but oh well.
SecondNight.jpg

Joe Kerman

unread,
Aug 11, 2012, 11:36:01 PM8/11/12
to sect...@googlegroups.com
Its looking good!

Are you sure the wires on the motor arent touching when you try to spin it?  We have a box-o-steppers at sector if the motor ends up being bad

You ordered this as a kit right? if they are mass producing something that doesnt line up that would be a huge bummer.

To view this discussion on the web visit https://groups.google.com/d/msg/sector67/-/ytNt1jpruloJ.

Jesse Robinson

unread,
Aug 12, 2012, 2:25:59 AM8/12/12
to sect...@googlegroups.com
I don't have the wires connected, but it is possible metal shavings got in there and are shorting it.  I'll blow it out even more before I hook it up (as well as measure with a meter).

I ordered the mechanical kit, they are doing another run here

I have all the electronics, and I've been trying to kludge my parts in.  My steppers use 4-40's, and no one around here has 2" long 4-40 screws (some don't even have 4-40 screws, like Fleet Farm!), so I used threaded rod and put nuts on the back, and I've bought some new spacers, basically made 5-6 hardware store visits today :-)

Yeah, apparently batch1 had a similar issue with the holes not lining up, they said its within the spec for makerslide but they were going to talk to their extruder.  You'd think they add slop enough so the tolerances wouldn't line up like this.

I'll bring this to Sector next meeting, it should definitely be up and running by then.  I probably won't have my new spindle, I want to get a dewalt DW660, but it should be functional on plastic and wood with my dremel.
Reply all
Reply to author
Forward
0 new messages