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if you cant get 8mm can you get 10 or 12? That would be a better way to go.
by
Greg Frost
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General
Why cant we design and print a screw terminal style connector that uses m3 screws/nuts/washers to clamp the connections. Then all you need is the fasteners.
by
Greg Frost
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Plastic Extruder Working Group
pm sent.
by
Greg Frost
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Wanted
Sublime Wrote:
-------------------------------------------------------
> I've never experienced the effects of resonance
> that Nophead wrote about because I use firmware
> with acceleration. So if its an effect of
> resonance and you don't want to go through the
> hassle of editing the G-code, I would change to a
> firmware with acceleration.
Even with acceleration, this will
by
Greg Frost
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General
Re: PLA - 13 years ago
0.000009kg /mm not g
Each 11mm length of 3mm filament should weigh 1 gram.
I think Skeinforge reports the length of extrudate rather than input filament.
by
Greg Frost
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General
Re: PLA - 13 years ago
100m of 2.9mm filament weighs 0.9 kg:
from here:
by
Greg Frost
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General
use mechanical endstops instead of optos (~$1 microswitches).
Kapton can be obtained from dealextreme very cheaply $5 for 25mmx30m this will cover a bed many times over.
printing larger parts even with PLA can be difficult without a heated bed.
by
Greg Frost
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General
Here is a pic of the underside of my bed:
by
Greg Frost
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General
I use a 1600W clothes iron with the water tank and handle removed.
Attached to 3mm alu bed with countersunk screws.
Bed covered in 2mm glass.
I had to cut the tip off to get it to fit under the bed properly.
Pros:
Very inexpensive ($14 + fixings)
Very fast heat up (1600W)
Integrated thermostat (just turn the dial to select the temperature).
Mains voltage. No need for a power supply.
Most irons c
by
Greg Frost
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General
You could try my coupling: It uses 3 M3 screws as a 3 point vice to grip an M8 nut locked onto the top of the z rod. I drilled small dimples with a 4mm drill bit in 3 sides of the nut for the M3 screws to sit in. Once you clamp the nut, you can spin the z rod by hand to see if it is alighed, and adjust the 3 screws if necessary to align it:
by
Greg Frost
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General
8mm seems like overkill (and added weight). I use 3mm with a 2mm glass sheet cliped to the top. I have printed PLA linear bearing holders undreneath that I separate from the print bed with a 18mm square block of wood (using countersunk wood screws).
by
Greg Frost
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General
T2.5 wont increase resolution unless you have a smaller pitch diameter on the pulley. You wont be printing T2.5 rez pullies, so the manufactured pullies may result in higher accuracy than T5 printed pullies, but there are a number of other factors that affect your accuracy. You know the diff between resolution and accuracy right?
by
Greg Frost
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General
I'm guessing uhmw is ultra high molecular weight somethingorother?
By thickness, do you mean viscosity?
by
Greg Frost
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General New Machines Topics
I had lots of issues trying to use an extruded without springs. if you can't get springs of sufficient strength, how about cutting some rubber washers from an old inner tube (or some other source).
by
Greg Frost
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Plastic Extruder Working Group
Using the z mount to clamp the rod was what I was thinking. This will reduce rigidity of the machine (as would widening it) so you would have to assess whether that was going to be a problem. Also if you have the rods bar clamped at the bottom and z-motor clamped at the top, you have lost the means to adjust them so they are parallel.
If someone could come up with a design for an adjustable bar
by
Greg Frost
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General Mendel Topics
If you turn it around, it would also make sense to put the smooth rod on the inside of the threaded rod. That way you can do away with the threaded rod across the bottom of the machine and 2 bar clamps and 2 rod clamps all together.
by
Greg Frost
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General Mendel Topics
+1 for RAMPS
by
Greg Frost
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General
There is also reasonable scope for printing finer layers (i.e. less than the standard 0.4mm layers) with a 0.5 nozzle just by slowing the flow rate appropriately (and indeed I think the volumetric calculations in skeinforge 40 do this automatically for you).
You then start running into issues with things like bridges and sharp corners because you are stretching the filament.
As you reduce the n
by
Greg Frost
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General
Regarding molten plastic smell: print with PLA. It has very little odor, and what odor there is is quite inoffensive. Many people say it smells like toffee or fairy floss.
by
Greg Frost
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General
I was thinking we should do this sort of thing in openscad itself. That way it would be easier to maintain as the design evolves. When I looked at doing this though, it was complicated by the placement of the individual parts in the current design. That could be resolved, but any changes would have to be flowed through to all of the production plate flles. The next step would be to get the opensc
by
Greg Frost
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General Mendel Topics
what are you planning for the interface between the mig tip and the tube? I think you may benefit from drilling out the top of the mig tip to 4mm and using some 4mm OD, 3mm ID PTFE sleeving that goes all the way up the middle of your insulator and most of the way into the hotend. That will ensure a smooth and slippery surface where the hot end meets the cold end. If you read up on extruders, I th
by
Greg Frost
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Plastic Extruder Working Group
If its not strong enough under tension it wont be the end of the design, you might just need to add a plate to the bottom with bolts going to the top so that it is under compression (much like some of the peek block hotends work).
by
Greg Frost
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Plastic Extruder Working Group
Belt stiffness plays a significant role here too. With a stiff belt, you need more tension and when you dont have enough tension, the belt doesnt come off the idler at a tangent, but instead arcs up a little bit. The amount it arcs up varies depending on the tooth phase on the idler, so if you watch the belt as the axis moves in one direction, it nods up and down. Perhaps nophead's belts are more
by
Greg Frost
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General Mendel Topics
I have seen that effect on my Y. I think it depends on belt tension. If you get the tension just right, the stiffness in the belt at the radius of the idler means it comes off the idler smoothly. With the belt too tight, the belt nods up and down as the teeth roll over the idler causing the madscifi flaw. Too loose and you probably get it too with a bit of backlash to boot.
by
Greg Frost
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General Mendel Topics
I have always done the same as brnrd: left the w/t the same when changing layer height and adjusted the flow rate by the square of the change in layer height. I can see that this is sub-optimal for bridges (and indeed with 0.25 layers, many of my bridges snap on the first crossing attempt), but without bridges, the print resolution is improved by extruding a smaller cross-section. I tend to use 0
by
Greg Frost
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Skeinforge