MendelMax 3 Build Guide

MendelMax 3 Build Guide
Maker's Tool Works
MendelMax 3 Build Guide
Instructions for the building of the MendelMax 3 3D Printer.
Written By: Micro
Thanks for your purchase of the Maker's Tool Works MM3!
Please follow this link to our new manual
Screw Drivers (1)
Allen Wrenchs (1)
Pliers (1)
Scissors (1)
Wire Strippers (1)
Drill (1)
Xacto Hobby Knife (1)
Small File (1)
8mm Open Ended Wrench (1)
10mm Open Ended Wrench (1)
© 2015
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MendelMax 3 Build Guide
Step 1 — Getting Started
Welcome to the the MM3 build guide. This guide will attempt to make your assembly of the
MM3 printer as easy as possible. With the MM3 being a new printer design the manual
may have an occasional error or lack detail needed to make the build easier.
If you find a difficult spot please use the comment section to help us improve this guide.
Assistance can be obtained via our Help Desk System or our Web Chat Room.
The first step of the build will be to ensure you have the parts you need and that none have
been damaged during shipping. Please check all boxes and bags before filing a missing
part request. We will sometimes pack parts in unusual locations to protect them from
shipping damage!
Below are some references you might find useful.
Use this interactive 3D model to get an idea of the complete assembly. Download it and
click on the model, use the model tree button on the left or on individual parts to hide/show
them: MendelMax 3 3D Model
STLs for printing are available here: MendelMax 3 STLs There are some prints which your
will complete once your MM3 is running. These can be found in the optional folder. Fan
mounts and cable chain being the most popular.
The main components (the fasteners won’t fully match and Upgrade Kit will also not
receive all parts listed):
Firmware to be uploaded to the Rambo Controller: MendelMax 3 Firmware
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MendelMax 3 Build Guide
Step 2 — MM2 to MM3 Upgrade Kit owners please read!
Most of your build will follow the full kit build. A few exceptions are noted below. Depending
on how you route and install your cables you may be required to extend some of them to
be able to reach the controller.
The upgrade will reuse your 20 tooth pulleys. Full kits receive 16 tooth. You will need to
change the E step for the X and Y with the new firmware from 100 to 80.
If you are reusing your maxstruder you will need to change the E steps for the extruder to
480 from the 99 that is in the new firmware. If you are using the new style extruder you do
not need to do this.
If you are reusing your old leadscrews and nuts the Z step needs to be changed to 1600
from the 400 in the MM3 firmware.
From your MM2 you will reuse 5 of the 2020 extrusions. ( remember one is located under
the Y rail. ) pulleys, stepper motors, controller, power supply, usb cables, heated bed,
glass, glass clips, rubber feet and possibly some assorted screws.
Standard kits will reuse the leadscrew and nuts as well as the maxstuder. Deluxe kits
receive the same parts for these as the full kit.
The upgrade kit comes with an adapter to use your old maxstruder so you can use up your
3mm filament before converting over to the new style extruder. There is a pdf in the
extruder section that shows how these pieces assemble.
The upgrade kit requires use of the 3 micro switches that came with your Rambo
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MendelMax 3 Build Guide
Step 3 — Plate Identification
The picture in this section will help you identify the plate parts in the MM3 build.
You can select pictures in the bar above to bring to main focus. You can then click on the
picture to see a larger version.
* The Top Deck Side Plates "I" are now two pieces on each side. The pictures in the guide
are showing the beta version. The production version will be two.
 Included in the kit will be some small metal pieces for the extruder as well as the belt
clamp for the bed plate. These parts may be still attached to a carrier metal plate and
have to be removed.
Removal is accomplished by hitting the small part in the carrier so one side can be
grabbed with pliers and then flex back and forth until it breaks free of the carrier.
 Included in the kit are some long bent plates that are not shown in the parts list above.
There are 4 of these plates and they look very similar to the Stiffener Plates. These are
used to mount the PSU and Rambo.
Part F in the picture has been modified for the production version. Part F for the Z motor
mount looks almost identical to part E. There will be two of these plates.
To better protect the plates during shipping several of them are packaged in different
boxes and plate wraps. Please open every box and bag to check for your plates!
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MendelMax 3 Build Guide
Step 4 — Important Build Notes Before You Proceed.
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MendelMax 3 Build Guide
Many have purchased the MM3
with dual extruders. We strongly
recommend you get your printing
working well with a single extruder
before you attempt printing with a
dual extruder configuration.
If you are attaching a metal plate to
an extrusion you will need “two” 5m
washers. The exception being the
front and back plate of the frame.
Use a single washer just on the
front plate and use no washers on
the rear plate.
16 m5-10 screws are used on the
top deck of the Y plate, the 4
screws that attach the top U
channel plate to the Z extrusions,
and 8 on the 90 degree brackets
that attach the X extrusion to the Z
 Do NOT cut belts until very end
of the assembly and you are sure
the length is correct.
Some of the extrusion are tapped
only on one side. On the Z 2040
extrusions the tapped holes go up.
On the 2060 X extrusions the taps
go to the left side.
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MendelMax 3 Build Guide
 Fan polarity matters. If you get it
wrong you will destroy your
fans. Black is - “minus” Red is “+”.
If you get this backwards you will
ruin (meltdown) your fans. double
check these connections before
you power up. The + and - are
marked on the Rambo in very small
text. You may need a magnifying
glass to see them.
There is a sticker on your power
supply to make sure you select
your countries supply voltage.
Please make sure you do this or it
is possible to damage your
expensive electronics.
Included in each wheel bag is a
thick washer. This washer goes in
the middle of the wheel between
the two bearings. If not installed
you will not be able to tighten the
wheel down properly.
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MendelMax 3 Build Guide
Step 5 — T-Nut proper installation
The T-nuts are installed with the protrusion toward the extrusions. The kit may include the
following type of T-nut as well. This is called a post install nut and is very handy when you
forget to get a T-nut in an extrusion. This T-nut can be installed at any time.
There are three types of T-Nuts that may be included with your kit (Shown in picture 2).
Either the Blue or Purple can be used for general asssembly (the ends of the purple t-nuts
may or may not be tapered).
The Green (middle) box shows a Post Install Nut that you can place the T-nut into the
extrusion and roll into place until the the small roller balls centers on the groove in the
center of the extrusion.These allow you to add a nut after you have installed a particular
 The picture showing the T nuts installed in the extrusion shows the correct way to install
them and is highlighted. Method circled in RED is the Wrong way.
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MendelMax 3 Build Guide
Step 6 — Base Frame Assembly
Install the 4 extrusions 2020-420mm on the outside corners of the front and back plate as
shown using M5-8 SHCS. Finger tighten these 8 screws for now. The opening for the
power connector and the usb connector can be reversed by turning the rear plate 180
No washers are need for the M5 screws on the back plate. Installing washer on the back
plate will complicate future assembly sections.
On the two top extrusions of the frame install 2 T-nuts on each sides bottom slot. These
will be used later to mount the Z motor mounts. If you assembled past this point you can
remove either the front or back plate and install them then re-attach the plate.
Install the two lower side plates as shown using M5-8 SHCS with 2 washers per screw.
Pay attention that the single top hole on the side plate goes to the rear of the machine and
the two upper holes go to the front.
Place the frame on a flat surface and tighten the lower side plates followed by the
extrusions. Try to keep as square as possible. Attention needs to be given to the picture to
make sure you have the plates facing the right directions.
The use of a small triangle square will help with squaring up the base. If one is not
available you can use the Hatch Cover Plate as a makeshift square.
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MendelMax 3 Build Guide
Step 7 — Base Frame Part 2
The two Z motor mounts attach to the frame one on each side near the rear. You can
measure the distance of 88.5mm from the back plate to the back edge of the motor mount,
or you can align the motor mounts to the 2040 Z extrusion that mounts to the side of the
You can also temporarily install the 2040 Extrusion onto the Side Plate Frame and use a
small square to align the Z motor plate to center of the 2040 extrusion or you can measure
as detailed here.
With the frame at this point you can install the 4 rubber feet to the bottom of the frame in
the slot of the 2020 extrusions. You can assemble the foot as below (using M5-14 screws)
and slide the foot from the back of the printer into place.
 Add T-Nuts, 4 per side, between each set of feet for the electronics mount later.
The base frame at this point will not be very sturdy. At a later stage during the Y assembly
the frame will become much more rigid.
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MendelMax 3 Build Guide
Step 8 — Y Axis Assembly
Slide 8 T-nuts in top of each 2020-420mm extrusions, install V Wheel rails, with plate on
top using M5-10 screws with two washers, leave slightly loose Use the top deck plate to
align the T-nuts in the two extrusions to line up the holes for the top plate/ V-rail / T-nuts.
 ** Note the detail picture. The v-rail outside edge goes up and lines up with the top deck
plate to give accurate spacing of the rails between each other. This area is highlighted.
Place the two long V rails on top of the two extrusions.
Once aligned place the top deck on top of the V-rails and then use M5-10 screws with two
washers to secure the assembly together. Only finger tighten the screws in this step, they
will be securly tightened in a later step.
Add 5 T-nuts in bottom of extrusion by the long slit, and 4 in bottom of opposite extrusion
and put on the two end stiffeners loosely. The stiffeners are part G and look very similar to
the bent metal parts that mount the PSU and the RAMBo. The stiffeners are shorter and
have two holes for mounting on each tab that sticks out.
The top deck plate should be adjusted so each end overhangs the extrusions equally. This
overhang is what in later stages will sit on top of the front and back plate to ensure the top
deck is level to the base section.
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MendelMax 3 Build Guide
Step 9 — Y Axis Assembly Part 2
Attach the Y assembly to the frame using 6 M5-8 screws, 2 in front, 4 in back. Get a small
square or plate J hatch cover and square up the frame with the Y assembly installed. Once
you are square : tighten 4 extrusion and two stiffener screws on ends. The front stiffener
should be about 2 washers thickness away from the front plate.
Tighten the 8 bottom stiffener screws, tighten 8 right top deck screws with rail flush to
extrusion. Then tighten the 8 left top deck screws.
You will now remove the Y assembly by removing the 6 screws holding it in place. When
the Y assembly is reinstalled later the Y assembly will bring the lower frame back into
square. Slide 3 T-nuts inside left extrusion, 2 for y motor, 1 for idler mount Y motor plate
assembly inside left extrusion.
Use the stepper motor without the black sleeve around the wires for this step. The long
lead (black covered wires) are used for the X and the extruder. Short cables are used for
the Y and the 2 Z motors.
Use the supplied M3-6 button head screws with a 3m washer to mount the Stepper Motor
to the Y motor mount plate.
In the picture one bearing set is mounted with a M5-16 and M5 nut. The other two are
mounted with M5-20 and T-nuts. The assembly order isM5 screw, washer, bearing,
washer, bearing, 2 washer, plate, nut. Use extra washers as needed.
The Y motor mounted in its proper location is set back about 10mm from the front of the
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MendelMax 3 Build Guide
Step 10 — Y Axis Assembly Part 3
Pictured is a detail for the Y idler bearing. This mounts at the opposite end of the Y motor
mount and is the far side return point for the Y belt. Installation is an M5x20mm screw, 605
bearing, washer, 605 bearing, washer, D idler plate (C), extrusion, T-nut.
If required add a washer to ensure that the bearing properly tightens down. Washer ID and
OD are fairly precise but the thickness is not.
To properly install the bed plate and wheels you need to identify which end is up! The
production version of the bed plate will have the bent sides facing up and the front and
back bends facing down.
Install the wheels to the bed plate. Make sure you have the screw head of the wheel screw
on the top of the bed plate. Use the wheels that have the V slot cut into the center of them.
The larger holes on the left hand side will require the special eccentric spacer on top of the
bed plate. The smaller holes do not use this special spacer.
 When installing the wheels the nut will be next to the wheel. Refer to guide here: V
Slot Wheel Assembly & Adjustments
Once the wheels are installed slide the bed onto the Y frame. The front of the bed will have
screw holes for two glass clips on each front side. The front of the Y frame will be end with
the Y motor. Turn the eccentric cam to make sure wheels slide on easy to the rails.
Install the Y belt offset printed part to the bottom of the bed once the bed has been slid
onto the rails. This part runs in the slot in the top deck that goes from front to back. Use
m3-x screws and m3 nuts to mount this piece.
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MendelMax 3 Build Guide
Step 11 — Bed Assembly
To install the belt put both ends of the belt into the hole in the belt offset piece. Fold the
belt over on the top of the bed and secure with the small belt clamp. This clamp screws to
the bed with M3-6 button heads. This is a metal piece in the production kits and may be
attached to a round metal piece and needs to be broken out of the carrier.
 Route the belt as show in the picture in this section. loosen the belt clamp to take up the
slack of the belt. Do not trim the belt.
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Step 12 — Bed Assembly Part 2
The rear clip is installed with a m5-14 screw being inserted from the bottom and threading
into the rear glass clip. The hole the M5-14 passes thru is located to the back of the bed
The front glass clips are installed as shown. The screw at the front is a M5-20 screw with
a M5 nut installed on the screw before being installed into the bed plate. The second screw
is a M5-8 and it threads into hole in the glass clip.
The kit is supplied with a strip of silicone rubber material. Cut this strip into 3 pieces,
remove the paper backing on the adhesive side and stick the silicone piece to the glass
clips as show in the picture of this section.
The two front glass clips will be used to secure your glass in place. You push in on each
clip and tighten the screw that threads into the glass clip to secure it in place. This will be
done with both front glass clips.
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MendelMax 3 Build Guide
Step 13 — Bed Assembly Part 3
Unpacking the glass bed: The glass is taped to styrofoam to protect it during shipping, cut
it free then the tape can best be removed by using heat from a blow dryer or a solvent like
rubbing alcohol with a scraping tool. Goo begon has also been used effectively.
Remove the protective sheet from the Aluminum Heat Spreader. * This film is not on the
Heat Spreader if the color is black, red, or blue. Silver only has the protective film.
 Important: Identify any bow in the Aluminum Heat Spreader, if one exists the bow should
arch up so the glass will help flatten the Spreader. The other side will get the heater. Align
and center the Heater on the Spreader and use some tape to attach them for easier
Fold the heater back and peel a corner off the backing to expose the adhesive.Slowly
apply the Heater to the Spreader, peeling off the backing as you smooth out the heater.
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MendelMax 3 Build Guide
Step 14 — Bed Assembly Part 4
If you like can reinstall the Y Axis
on the frame now, but you might
find it easier to wait until after your
electronics are wired.
Install the black rubber grommet
into the circular hole you will feed
the cables through (not shown)
Use about 240mm of wire loom to
cover the heater wires. Important:
When mounting the Heater Secure
the wires with a ziptie to the side
tab of the Y Plate. Route the cables
down the hole located between the
two wheels on the right hand side.
 Place the Heater and Spreader on
the Y Plate with the heater down
and the Glass on top. Attach the
Heater to the Heat Bed port and
the Bed Thermistor to T2 on the
RAMBo. Level the glass by
following the next section then
secure it using the two front Glass
 The bed shown in the pictures in
this section are of the beta bed
plate and will be different than the
production version. * the side
bends on the production kit face
up. The wheels are installed with
the nuts on the bottom and not on
the top as in the picture.
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MendelMax 3 Build Guide
Step 15 — X Axis Assembly
In the 2060-450mm extrusion place 2 T-nuts in slot 1 and same in slot 3 on the front.
Loosely tighten the 90 Degree Brackets to them, approximately 30mm from the edge of the
On the tapped end place 1 T-nut in the middle slot about 20mm from the end. Assemble on
a m5-25 screw the following: bearing, washer, bearing, washer, bearing, washer and one
small D plate with two holes ( 3 bearings, 3 washers). It may be required to add extra
washers to ensure the screw does not hit the bottom of the extrusion.
Loosely tighten this assembly to the T-nut you installed in the middle slot of the X, either
inline (or a bit farther out) with with leftmost 90 Degree Bracket. You might need to add
washers if the screw is too long and bottoms out against the extrusion. (D plate shown
below. Used in the X and Y belt idler bearing assemblies)
Place a pulley on the motor, and attach the mounting plate to the motor - mind the wire
orientation we want the wire facing down when complete. On the untapped end place a Tnut in slot 1 and 3 on the rightmost side, and attach the motor plate, with the motor flush
with the extrusion end.
On the X Carriage install 4 wheels as shown. The nut mounts to wheel side as outlined in
the wheel documentation. Slide the X Carriage on to the assembled X Extrusion. Note: In
the picture the orientation is correct, the notch in the carriage moved to the bottom.
 The carriage plate shown in the picture is a beta version without a U slot cut into
the bottom side of the plate.
In the final orientation the left side of the extrusion is where the tapped holes and idler
pulley are located.
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Step 16 — X Axis assembly Part 2
Mount the rear carriage plate to the front carriage plate with the supplied m5-30(upgrade
kit users please use m5-35 provided screw). Install the two supplied printed spacers while
doing this step. The curved part of the spacer faces down. The rear metal plate for the X
carriage is packed in the electronics box for protection.
 The production X spacer provided have a U channel. This U is to face down and match the
front X carriage plates downward facing U cut into it.
Zip tie one end of the belt to the clip on the back X plate (pictured) Place the plate in the
middle of the extrusion, run the belt around the pulley, to the bearing, and the other side of
the X plate more or less tightly. and and zip tie it.
Loosen the bearings screw, and push it toward the edge of the extrusion as far as you can,
and tighten it. You want the belt to be just tight enough to make a low sounding note like
plucking a bass guitar string. We want it to just barely make a note. A thud sound is not
We are complete with this portion of the X assembly. Set the X aside we will return to it in
the Z assembly section.
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Step 17 — Z Axis Assembly
To begin the Z assembly install the 2040-340mm extrusions, with the tapped end up, to the
lower side plate as well as the two short 2020-300mm extrusions. At the top of these two
extrusions you will mount the upper side plate as pictured. For this section we recommend
removal of the Y section from the frame.
Check the lead screw for any burrs like shown in the picture. If you find any you can
remove them with a small file. Screw the leadnut on the leadscrew and make sure that you
can turn the nut with just one finger and thumb.
If you cannot easily turn the nut you will need to chuck the leadscrew into a drill and run
the screw back and forth until it becomes easy to turn with a single finger and thumb.
Next assemble the Z plates (X2) as shown. The leadscrew nut will mount to the leadnut
bracket with m3-10 screws and m3 nuts. This will in turn mount to the Z plate with two m36 button head screws. ( You can skip mounting to the leadnut assembly to the Z plate in
this section.)
Install the wheels into the Z plate. Use the eccentrics and special spacers for the two
larger mounting holes.
Install all wheels with the nuts for the wheels on the plate side of the assembly. If you
mount the nut on the wheel side for this section the nut will catch on the upper side plate.
Install the two Z plate assemblies onto the 2040 upright Z extrusions. Make sure the
square hole in each plate is facing the front of the printer. The metal plate itself goes to the
inside of the 2040 extrusion as shown.
Turn the eccentric cams on each plate using a wrench until all wheels are just snug and
don't easily slip when you try and turn them with your finger and thumb.
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Step 18 — Z Assembly Part 2
The installation of the X needs to be done with the X lowered to the bed height. Attach the
X assembly to the Z section. You will use 4 m5-10 screws and nuts for attachment.
Loosen the 90 degree brackets on the X and slide to align. The 90 degree brackets mount
to the outside edge of the Z plate.
Install a 90 degree bracket on the inside face, front channel, of each Z upright 2040. One
of the flat sides of the 90 goes to the 2040 and the other flat side will point up and attach to
the Top Frame U Channel Plate of the next step. Finger tighten the mounting screw it will
be securely tightened once the Top Frame U channel plate is in place.
Install the Top U Channel Plate with 4 5m-10 screws. The front of the plate will have 3mm
holes and will be shorter, the back has 5mm holes and is taller.
We will now align the Z 2040s. Remove the screws that connect the Leadscrew Bracket
plate to the Z plates (m3-6) on each side. Loosen the two screws on the Top U channel
that are located in the slotted holes.
Move the X assembly all the way to the top position and tighten the screws in the Top
Frame U Channel Plate. Move the X assembly up and down several times to ensure that it
moves smoothly in the tracks. Take care to keep it level during this so it does not bind.
With the spacing of the Z uprights now set loosen the 90 degree brackets and move them
to the top against the Top U Channel. Install the M5 screw that connects the 90 degree to
the Top U channel. Then tighten the screw that holds the 90 degree to the 2040 extrusions.
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MendelMax 3 Build Guide
Step 19 — Z Axis Assembly Part 2
Install the stepper motors for the Z in the mounts you installed in frame assembly step.
Keep the 4 m3-6 button head screws loose until a later step where we adjust the motor.
Install the helical couplers on the Z stepper motor shafts.
Install the leadnuts onto the leadscrews. The wider flange of the nut goes to the end of the
leadscrew that has a shorter turned shaft. The longer end is what will mount to the helical
With the leadscrew nut installed on the the leadscrew you can now install the screw
assemblies. Place the long turned end into the helical coupler and adjust the nut to a
position to allow you to screw the leadnut bracket to the Z plate.
Install the top front plate with " Makers Tool Works " using 4 m5-8 screws, two Tnuts and
two m5 nuts. Note: the top hole on each side only receives a nut on the back and is for
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MendelMax 3 Build Guide
Step 20 — Extruder Assembly
Install the Aluminum hotend block to the carriage with 3 M3-10 screws inserted into the
deep holes that are center front of the block. ( highlighted in picture ) Verify after
installation of these screws that the X still moves freely. to long of a screw will bind the X
Install the Stepper Motor with the long leads to the printed extruder body with 3 m3-6
screw, do not install the screw in the top back position. This will be the hole that later
attaches the lever arm to the extruder body.
Install the extruder printed body to the carriage with two M3-8 screws. Also attach this
piece to the Hotend Block with a M3-20. The hole for this connections is in the upper left
corner of the block.
Assembly of the lever arm will include two metal side pieces, two small metal screw
retaining pieces, a printed plastic lever arm piece, a Tnut, 1 M3-16 screws, 1 M3 nut, two
M3-6 screws small bearing, and a M5-16 screw.
Note: there is a hole in the middle of the arm plate on each side. Do not install a screw in
this hole. Marked with a red circle in the picture for this section.
The small retaining metal parts are held in place with the slots cut into the metal side
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MendelMax 3 Build Guide
Step 21
Install the small bearing in the location highlighted. Use m3 washers to center the bearing
to the small filament guide hole in the printed plastic part. Use a m3-16 screw and nut to
secure the bearing and washer as shown.
Note the T nut installed on the tension screw. This T nut rides in the square holes cut into
each side of the metal plates.
Install the completed lever arm to the extruder body with a m3-30 screw using a washer
next to the screw head. Use thread lock on this screw. Tighten but leave loose enough so
the lever arm can move.
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Step 22 — Extruder Assembly Part 2
Install the completed lever arm to the extruder body with a m3-30 screw using a washer
next to the screw head. Use thread lock on this screw. Tighten but leave loose enough so
the lever arm can move.
Install the Brass hob onto the stepper motor shaft. You will need to squeeze the lever arm
down to do this step.
 For the assembly of the E3D V6 Hotend please use the documentation located at and a video tutorial located
Trim the ptfe tube (white) as shown in the picture. This will ensure that the filament does
not try to bow out as much from the hob to the hotend causing a jam. Shown circled in
Install the hotend from the bottom of the hotend block. You may have to raise the Z to have
enough room to do this step or you can remove the screws that hole the leadnut bracket to
the Z so you can easily move the Z up and down.
 The production version of the hotend block has two holes in the front for setscrews to
secure the hotend in place. The set screws should be tightend so the screw hits the top
groove cut into the hotends outside edge at the top of the hotend.
Hotend groove denoted in the picture with a square box.
With the hotend and the lever arm in place you can now adjust the hob to be centered in
the filament path. Look down the small filament hole on top of the lever arm and adjust to
location of the hob then tighten.
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MendelMax 3 Build Guide
Step 23 — Extruder Assembly Part 3
For those doing a MM2 to MM3 upgrade use the picture in this section as a guide for the
extruder conversion.
The plate that receives the hotend that is 90 degrees from the motor mounting plate gets a
screw and a nut on the far left hand side hole. This screw is the bottom retainer for the
The lever arm, hob, bearing all build just like the mm2 did.
The hotend is secured with the lower filament guide printed part along with the metal piece
shaped similar as the lower guide. Use M3 screw and nut to secure the hotend to the plate.
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MendelMax 3 Build Guide
Step 24 — End Stop Installation
Install the Y endstop as shown. The micro switch is mount to the printed piece with
supplied m2 screws. The switch mounts with a single m5-8 and a washer to bottom of the
left extrusion of the Y. The nut of the wheel assembly engages the micro switch for
It might be required to slightly bend the metal lever of the micro switch up to ensure that
the lever engages the wheel nut.
The Z endstop consists of two printed parts, a micro switch, and a m5-60 screw. Install the
switch into the printed part and then mount the assembly with m3 screws and nuts to the
rear plate of the side deck left side as shown.
Refer to the 3D pdf for the mounting
location of the printed part that holds the m5-60 adjustment screw for the Z.
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MendelMax 3 Build Guide
Step 25
Install the X endstop as shown. The micro switch mounts behind the printed plastic mount
with two provided m2 screws. The endstop mounts to the lower left side of the X extrusion.
bottom slot. You will need to bend the terminal on the switch for the connector to fit.
 Note the lever arm of the switch face down. If mounted with the switch going up it will hit
the 2060 X extrusion and not work properly.
Connect all endstops with the cables shown. These cable are packaged with the Rambo
controller. You will use the two outside post on the micro switches.
The Endstop cables will connect to the area highlighted in the picture. The lettering for
each port is small but on the board. Install the cables to the X, Y, Z min connectors.
The board has a MAX xyz input as well and is not used with our printer.
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Step 26 — Rambo Controller / PSU Wiring
A separate guide for the wiring of your controller is located here: Wiring Rambo
Electronics & Power Supply
The long bent plates are mounted to the bottom of the frame as shown in the picture. The
rambo mounts to these rails with the supplied spacers. The recommended order is screw,
rambo, spacer, 3mm washer, rail, washer, 3mm nut. This is done for all 4 mounting holes.
The spacers for the above step are whitish plastic tubes with a flat on one end. Detail is
shown in the highlighted box in this sections pictures.
The PSU is mounted with the M4 screws provided with the kit and mounts to the second
set of rails as shown in the picture. Make sure the screw does not hit the printed circuit
board inside the PSU case. Use washers on the M4 screws as needed.
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Step 27 — Led Strip Assembly
The Led controller has three connections. One to the 24 volt power supply with the red
wire going to the “+” and the black wire going to the “-”. You will have to share a screw
terminal with the Rambo and Led Controller wires. Marked with circles on the PSU picture.
The second is the I2c data connection to the Rambo controller. The I2c is near the endstop
inputs to the Rambo board. Arrow in picture below shows the I2c Port. The 3rd is the
connection to the second 10 led strip.
The cable for this connection is keyed and will only fit in one directions into the I2C. ( MM2
upgrade kits with the older version of the Rambo may have to solder a 4 pin male header
into the blank I2C holes. Please refer to your paperwork that came with the Rambo board
for the exact location of the I2C connector.
All newer version of the Rambos have this connector installed.
The cable will need to be routed on the right side of the machine to ensure that the cable
can reach the top led strip properly.
Included in the kit are two pieces of plastic with white protective covering. Remove the
protective covering from both sides of the plastic. The longer upper piece can be mounted
with M3 screws short for one variation of mounting or long for another listed below.
The shorter bottom piece of plastic for the Mendelmax 3 text can be mounted with Super
Glue or thin double sided adhesive tape. The 6 led strip will mount behind the Mendelmax 3
text. The 10 Leds part of the strip mounts to the top behind the Makers Tool Works text.
There are several mounting options for the led strips. During beta we found everyone want
a bit differnt distance and mounting options. The distance determines to what degree
hotspots of the individual leds have. Some mounted the leds to the back of the upper U
channel metal.
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Step 28 — Led Strip Part 2
Some builders prefered to mount the strip to the supplied cut plastic and use long M3
screws to adjust the distance. We have found that the adhesive on the led strips did not
work well on all surfaces. You can use zipties to secure the led strip to which ever version
of mounting you prefer.
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MendelMax 3 Build Guide
Step 29 — Hatch Cover
The hatch cover consists of 4 plastic pieces and the metal cover. Two of the plastic pieces
mount below the deck plate and can be seen in the hole for the hatch. One of the plastic
pieces mounts to the hatch cover, and the final printed piece mounts to the cover in the
cutout area to the front. All pieces mount with m3-6 screws.
The cover installs with the rear plastic piece of the cover aligning between the two tabs of
the plastic piece installed to the rear of the opening of the cover. Once this is aligned you
press the front of the hatch down to lock it in place.
If the fit is to snug you can loosen the screw that holds the printed piece and the retighten
with the printed piece pushed a bit further back.
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MendelMax 3 Build Guide
Step 30 — Spool Mount & Filament Guide
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The spool mount consists of plate
"S" a m8 bolt and two nuts. Mount
the plate halfway up the rear 2020
extrusion using two of the post
install nuts provided. Screw one
nut onto the bolt. Place the bolt into
the large hole in the S plate and
then secure it with the second 8mm
nut from the other side.
The filament guide is the 4mm OD
tubing and a printed part that is
user printed. The stl file can be
found in the " optional " folder
located at the STL link at the
beginning of this document.
Place a post install nut in the 2040
extrusion near the top. Place the
tubing into the hole in the printed
part and use an M5 screw to
tighten the clamp down. The other
end of the tube is free and rides on
top of the lever arm without being
When using the spool holder some
have reported the ridges on the
spool can hang on the screws that
mount the plate to the back
extrusion. You can cut a piece of
thin cardboard or plastic the same
size as a spool for a spacer to
keep this from happening
Place the spacer between the plate
and your spool.
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MendelMax 3 Build Guide
Step 31 — Bringing your MM3 online.
The startup guides for the MM2 and the FM will need to be used until we can complete a
separate section for the MM3. These can be found in the docs and support section on our
main website here: Assembly Guides
You can temporarily install your blower fans with zip ties with the blower opening facing
down until you print the fan mounts in the optional folder.
The Mac version of software is known to have issues flashing the Rambo Controller. If you
experience problems us the PC software.
USB 3.0 ports have been known to cause issues with programming and operation of the
printer. If possible always try to use USB 2.0 ports.
The latest version of our private labeled reptier host can be found here.
Arduino can be found here:
Rambo Driver is located here:
Marlin Firmware to be flashed into your Mambo controller is located here :
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MendelMax 3 Build Guide
Step 32 — Trouble Shooting
This section will try to detail the
most common problems our
builders have encountered and
solutions or workarounds for them.
We hope the build and use of your MM3 was as much fun as it was for us to bring it to you.
This document was last generated on 2015-05-04 04:08:43 AM.
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