H-1

This page was carried over from http://reprap.org/wiki/Seemecnc_h1 It will need some link updates etc...

Introduction
The SeeMeCNC H-1 design is based on the reprap Huxley. It is the first DIY-type 3D printer to use injection molded plastic parts. Our goal is to produce as many parts as possible with injection molded parts, effectively lowering the price into 3D printing, and turn to more conventional CNC technology, making it easier for newcomers to 3D printing and CNC machines. The H-1 is designed for standard SAE hardware. This includes the use of 1/4-20 threaded rods for the frame and Z axis lead-screws, 5-40 nuts/bolts for small sub assemblies, 10-32 nuts/bolts for others, and timing belts/pulleys designed around English units. Some other First's are dual-driven feed rollers, adjustable bearing backlash, dual resistor heating in the hot end, as well as compatibility with NEMA 11 up to NEMA 17 motors on all axes AND extruder.

=H-1 Assembly Diagrams=

Please feel free to add your own notes to the User Generated Build Notes Page: SeeMeCNC-H1 Build Notes.

Here is the complete official assembly manual (by:MHackney)

If you are using Mach3/EMC2, and have purchased the stepper board, standalone heat control etc..., here is the electronics assembly and wiring manual





















All of the assembly pdf's zipped up for download.





= Build Notes =

User generated SeeMeCNC-H1 Build Notes offer tips and advice you may find useful during your build

= Supplies =

All of the hardware should be readily available at local hardware stores. The plastic parts can be purchased from SeeMeCNC.com or from someone who has printed the parts from the CAD files.

Some parts, like the PTFE tubing and electronics, have come from sources other than local stores.

High Temp Silicone for installing thermistor/resistors is a great way to make those parts easily replaceable if ever you need to. Permatex Ultra Copper works best, as it's suited for 700F temps. It remains flexible and can easily be scraped off and re-applied if needed, and it's non-conductive.

Dimensions
Approximate Build envelope is 6" X 7" X 6" Overall Machine Dimensions are appx. 18" X 18" X 12" Weight of machine with extruder and all motors installed (not counting any electronics) is around 10 lbs.

Injection Molded Parts
SeeMeCNC.com makes our own tooling and injection molds our own parts

See below for all the .stl files of all the parts



Printed parts
At this time, no one is printing parts for the H-1. Some have printed replacements/repairs as needed, using the below .STL files

Electronics
SeeMeCNC is using Mach3 desktop CNC software for their machines, as well as RAMPS 1.4 and RAMBo by UltiMachine. Others have successfully used EMC2 on linux, as well as other RepRap electronics, such as Gen6, Sanguinololu etc...

They offer parts and hardware kits, as well as electronics packages for MACH3/EMC2 or RAMPS/RAMBo.

Note on the Velleman MK138 temp control board used with MACH3 electronics. If you are wanting to print in ABS, you will need to replace R5 on the board with a 10K-20K Ohm resistor to get up to 480+ F. The kit ships with a 120K Ohm for R5, but that will only allow up to around 400 F temps. An 18K resistor will allow over 500 degrees F, so I would recommend not going lower than that.

If you use a Velleman MK138 to control a heated bed, with the same Mouser 657-GC1396V-3-200 Thermistor as used in the Hot End, replace R6 with a wire jumper, to allow adjustment to the lower temperatures needed for the bed.



If you have the TB6560 driver board, you need to remove the opto-isolators and replace them with jumpers as shown in the photo below. This will fix any skewing, missed steps, and speed issues due to a low power parallel port on your PC

Firmware
Here's a link to johnoly99's (from SeeMeCNC) git repository. You can find firmware there that has been used/tested on their machines.

Johnoly99's Git

Repetier firmware/host
This section describes how to configure Repetier firwmare and Repetier host software to be used with the H-1. Some of the values provided are used for the H-1, but maybe used with any other 3D printer.

Hardware tested/used

 * Sanguinololu 1.3a w/Pololu step motor driver boards
 * Photo-interupter endstops
 * Nichrome heated print bed (custom design, but should support PCB and others)
 * Steve's extruder for the H-1 with NTC thermistor


 * RAMPS 1.4 from UltiMachine.com
 * RAMBo from UltiMachine
 * Printrboard

Also note that Repetier host/firwmware considers home to be 0,0 (and of course Z should be extruder nozzle at print table height).

Slic3r with Mach3
As of version 7 of Slic3r, simply using the Mach3/EMC2 Gcode flavor under the printer and filament tab is generating great looking results. If you are running an easy driver for the extruder control, set Mach3 to use A axis, and in motor tuning, set your steps per to 293 steps/mm for a starting point(others have reported that 284 steps/mm works well), and speed to 100 with accel of 50 or so. That will get you close. Also, here are the start/end GCODE you need to fill in when using slic3r:

Start GCODE G00 G90 G54X0.Y0. G92A0. G21

End GCODE G90 G20 G92A0. M30

Those are good start and end Gcodes for safe mach3 programs. Also, if you are using the standalone temp controller like a velleman kit, you need to set the temp to 0 and first layer temp to 0 also, which will remove any Gcode related to temperature control that Mach may not understand.

Steppers
H-1 machines use standard NEMA 11 through NEMA17 stepper motors. You need 4 motors total, 1 for each X, Y and Z axis, and 1 for the extruder.

NEMA17 steppers (4) provided in the kits are 4-wire 66.6 oz-in Wantai 42GYBH811, see specs at: http://www.electronicaestudio.com/docs/PH3303.pdf

Extruder
"Steve's Extruder", a gear-driven, dual-driven pinch feed roller design. It uses NEMA 11 through NEMA 17 stepper motors. The hot-end uses two 6.8 Ohm 3 watt wire-wound resistors, and 4K ohm @ 200C thermistor for temperature control. The gear driven unit has a gear reduction ratio of appx. 6.5:1.



For Reference: If you put the (2) 6.8 ohm resistors in series, and run them at 24VDC, you will get the same power (42W) as using them in parallel at 12VDC. The thermistor used in the hot end is a part number 657-GC1396V-3-200 from Mouser Electronics and can be found here: Mouser Electronics and the data sheet can be found here: Data Sheet. The wire wound resisters used to heat the hot end up are RWMA-6.8CT-ND from DigiKey.

Timing belt
Timing Belts are XL, in 1/4" width.

X = 25-3/4" length, secured to rear of extruder carriage bearing blocks

Y = 41" length, secured to bottom of table

Z = 310XL closed loop (31" length)

Bearings
The linear axes rollers use (stock) (32) Plastic Acetal molded bearings, or (custom) (32) R2ZZ (1/8ID x 3/8OD x .156W) ball bearings.

"Steve's Extruder" Uses (4) R4ZZ 5/8" x 1/4" bearings

Z axis support plates use (2) R4ZZ 5/8" X 1/4" bearings

In total, you need 6 R4ZZ ball bearings for the machine. IF you want to use ball bearings instead of themolded acetal rollers on the linear axis smooth rods, you will need 32 R2ZZ bearings to replace the acetal rollers.

Nuts and bolts
All hardware is standard inch units, except for stepper motor mounting, which are either 2.5mm or 3mm. 1/4-20 Threaded Rod 1/4" Drill Rod or similar(for linear rod, we ship kits with 304 Stainless Rods) 4-40 screws are used to hold the two metal hot-end plates together 5-40 nuts/bolts for sub assembly of linear bearing plates (1/2", 3/4", 1", and 1 1/4" bolts, and a total of 115 lock nuts in 5-40) 6-32 bolts are used to attach the hot-end, and the tension bolts in the extruder 10-32 are used on the idlers, 60 degree clamps and extruder single mounting bolt

NOTE on threaded rods, they are now shipped PRE-BENT as of 1/15/2012

To bend the 4 threaded rods(thanks, Yoyo): 1) Draw two lines on legal paper 3" apart. 2) Draw a 8.5" line connecting them 3) Take 9 nuts and screw them to the bottom of the threaded rod, all nuts abut each other and the last nut is flush with the end. 4) Take the 7/16" spanner, the same one you use for the other nuts and slide it about 1/4" above the top most nut. 5) Apply elbow grease and bend the rod until the angle matches that of the paper guide. 6) Repeat until done.

=.STL Files=

= Ongoing development =

Yahoo Groups page, compliments of Andy

http://tech.groups.yahoo.com/group/SeeMeCNC

Now, the forum replaced the Yahoo Group (but lots of info are on the yahoo group):

http://forum.seemecnc.com