HBP Leveling screws

[Jamesarm97]

I am about to replace some leveling nuts on my HBP. What is the
consensus on using nuts on only three screws (front two and one on the
middle back) as apposed to all four corners?

[Dan Newman]

Remember your high school geometry class: three points define a plane?
You can use four levelling points, but then it's an over constrained
problem-o. (And we all know that "over constrained" is a bad word or
two, right?) Sure, you can use four. But you can get by and
have an easier time of it, IMO, with just three.

Dan

[W. Craig Trader]

On the other hand, that assumes that your platform is an ideal plane.  I just did this, and went with the 4 corners, and it works great.  And I'm an instant fan of spring-loading the alignment screws.

- Craig -

--
You received this message because you are subscribed to the Google Groups "MakerBot Operators" group.
To post to this group, send email to make...@googlegroups.com.
To unsubscribe from this group, send email to makerbot+u...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/makerbot?hl=en.

[Jamesarm97]

I was thinking about the springs. Were did you get yours and what size
did you go with?

[W. Craig Trader]

I scavenged them out of non-working ballpoint pens.  Each spring was roughly an inch long, and I cut them in half, so two pens = 4 platform springs.  The springs were just big enough to fit around a 3mm screw.  I used the longer flush-mount screws that come with an aluminum build plate.  Top-to-bottom, I have aluminum plate, thermal paste, heater board, spring (thicker end up), wooden platform, then 3mm thumbscrew.  On top of everything, I have a nice layer of Kapton tape, which also manages to hold the screws in place if you need to disassemble/reassemble the HBP.

- Craig -

[MacGyver]

I too scavenged my springs from ball point pens (however they were all
identical brand new pens from work). Everything was going great until
today for some reason one of my rosette nuts worked loose and I had to
re-level the whole thing.

I would ideally like to find stronger springs because these ball pen
springs are frankly too weak.

If any of you find a source for slightly stronger springs I would be
happy to pay for them.

[Jamesarm97]

I just cut some I had from an Acehardware run a few weeks ago trying
to find a good spring for my new extruder filament tensioner. SP-9722.
Seem pretty strong. I cut them to just over 1/4" since that was about
the gap I currently have. I see how they work tomorrow since I am
printing stuff now.

7/32" x 1 3/8 x .028 7lb rated springs.

[Mark Cohen]

Makerbot uses pens from OfficeMax.
Sku: 22346828 mfg: om04169

Sent from my iPhone

On Feb 12, 2012, at 7:22 PM, Jamesarm97 <armstro...@gmail.com> wrote:

>>

[Tony Buser]

I've been using this arrangement (with springs) for quite a while now
and it works great. One thing I did recently add was another screw in
the middle front with no spring, just a nut underneath when I realize
my aluminum plate was bowing a bit there.