I made a 2.5up...but I need spare parts!!!

[WolfBrownie]

Oh, come on, why can't i attach any pictures. It's on 700kb?!?!?

[MisterAcoustic]

Hi WolfBrownie,

It should be fixed now, you should be able to attach files. See my post in the Site Discussion forum if it still gives you trouble.

Sorry about that - I ended up spending hours on something that my hosting provider said would work - and then it didn't work that way at all , That was yesterday. Today, they jumped in and fixed it for me (because that was actually the only option).

So that's been slowing me down getting things together to ship - my apologies. I hope tomorrow will lend itself to a little more progress on that.

Stan

[WolfBrownie]

Picture.. Bed disassembled for adding the new dual belt drive for the bed.

one more time for the picture...

[MisterAcoustic]

Hi WolfBrownie,

Sent you a PM regarding the printers/parts. Posting here in case you are looking without logging in.

Stan

[WolfBrownie]

Yah!  the mechanical parts I need for the new bed drive are here. Except for the one pulley I'm getting from MisterAcoustic.
I almost have my laser cutter back up too.  Geeze, at this rate, I'm going to have to finish this  2.5up off and get it working on something!  :-)

Wonder what my first part will be.  Probably a 1x1 test cube to check scale calibrations.

Bill

[Mooselake]

The problem using test cubes (or any other print then measure) calibration is that you're looking at multiple variables. Besides axis steps per mm you have variable width extrusion, so while you may be able to make a 1.000 inch cube a 2" cube will be off, as will any other size.

The best method is using factory produced pulleys, screws, etc. For 3D printed parts (which can be out of round besides off diameter) using a dial gauge to measure movements is more accurate (one variable only, axis movement per step), then separately calibrating your extrusion width.

This argument (the multivariate situation) was a big deal back when 3D printers were mostly printed parts, when measuring was your only choice. These days when most printer parts are molded/cast and machined in some giant factory their tolerances are beyond what most of us can measure, although there are a few guys out there with access to a metrology lab (run into a couple...) that can better what we mere mortals can do. And in the end they usually differ by a few parts per thousand or smaller. This puts them in the range of thermal expansion and contraction...

My one up (partial compensation for the RPM mess) never had enough working parts to be worth assembling so the usable bits went into the spare parts box

Kirk

[WolfBrownie]

So, you get to measure the outside dimensions and the inside dimensions of the wire frame.  You can then do the math and determine the actual center to center distance in all dimensions to figure our scaling factor.  All else being equal, a 2x2x2 or a 6x6x6 should scale perfectly.Assuming everything is scaled properly that is. :-)Bill Mooselake pid='404' dateline='1587052567']The problem using test cubes (or any other print then measure) calibration is that you're looking at multiple variables.  Besides axis steps per mm you have variable width extrusion, so while you may be able to make a 1.000 inch cube a 2" cube will be off, as will any other size.

The best method is using factory produced pulleys, screws, etc.  For 3D printed parts (which can be out of round besides off diameter) using a dial gauge to measure movements is more accurate (one variable only, axis movement per step), then separately calibrating your extrusion width.

This argument (the multivariate situation) was a big deal back when 3D printers were mostly printed parts, when measuring was your only choice.  These days when most printer parts are molded/cast and machined in some giant factory their tolerances are beyond what most of us can measure, although there are a few guys out there with access to a metrology lab (run into a couple...) that can better what we mere mortals can do.  And in the end they usually differ by a few parts per thousand or smaller.  This puts them in the range of thermal expansion and contraction...

My one up (partial compensation for the RPM mess) never had enough working parts to be worth assembling so the usable bits went into the spare parts box

Kirk

[MisterAcoustic]

Hi WolfBrownie,

As mentioned in my new PM to you, these images wouldn't fit into a PM, so I'm trying to attach them here. Well, I will attach them at some point, I don't know yet if I have to reconfigure the forum software to do it . Hopefully, here they are:


Well, that didn't work, the first time... Alright, trying to do it as attachments:

[WolfBrownie]

Woohoo New pulley acquired!  Now I just need to get the cooling system on the Laser done so I can cut the one piece I need to finish the 3D printer.... good thing I don't need to 3D print a part for the laser!!!!!