The Heavy Mill base consists of 4 to 6 x 40*40 cross extrusions and 2 x 40*120 Y Extrusions.
Parts List for 1000mm Base:
- 4 x 40*40 Base Supports
- 2 x 40*120 Y Rails
- 8 x M8*40mm SHCS
- 4 x T-Slot Connectors (With Tslot Base option only)
- 20 x m6 Tee Nut (With Tslot Base option only)
- 20 x M6x25 FHCS (With Tslot Base option only)
Parts List for 1500mm Base
- 6 x 40*40 Base Supports
- 2 x 40*120 Y Rails
- 12 x M8*40mm SHCS
- 6 x T-Slot Connector (With Tslot Base option only)
- 30 x m6 Tee Nut (With Tslot Base option only)
- 30 x M6x25 FHCS (With Tslot Base option only)
CAD Assembly of the base
Timelapse Base Assembly
X/Z Axis Setup
X/Z Axis Parts
|HGW20CC Linear Bearing Blocks||2|
|Hardened Steel Shaft||2|
|X Carriage Vertical Front||1|
|X Carriage Vertical Back||1|
|Z Axis Acme Thread||1|
|AT5 Belt Loop||1|
|Limit Switch With Lever||2|
|Limit Switch No Lever||1|
|Belt Clamp Bottom||1|
|Belt Clamp Top||1|
|X Carriage Horizontal Mid||1|
|X Carriage Horizontal Bottom||1|
|Drag Chain Bracket||1|
|X Carriage Horizontal Top||1|
|Nema 23 stepper Motor||1|
|8MM Steel Spacer for Acme Pulley||1|
|Z Motor Mount||1|
|Pillow Block Bearings SC16LUU||2|
|Z Axis Lead Nut||1|
|Spindle Mount Front||2|
|Spindle Mount Back||2|
|Spindle Carriage Plate||1|
|M8 Flanged Nut||1|
|Drag Chain end link||1|
|AT5 Pulley 10||1|
|AT5 Pulley 20||1|
|Pukley Grub Screws||4|
- DO NOT remove the black tabs from inside the bearing blocks!!
- The bearing blocks are not directly in line with each other, one is offset.
- There are 3 horizontal plates and two verticals.
- All plate screws are Countersunk M5 * 20’s
- The red and green bearing blocks take M6 countersinks (leave them loose)
- Do install the Flanged Bearings, Acme Thread, Hardened Shafts and Pillow Block bearings at this time so that it doesn’t have to come apart during installation of the Z Axis.
- The tolerance of the 6 holes for the shafts and flanged bearings is very tight! You will likely have to lightly sand the inside of the holes with some emery cloth to install the shafts and bearings, this is a pain but by design and necessary.
- The Star washers will help the Z motor grip in its slots, install at closest point to front, put on AT5 closed belt on then pull back tight and lock off nuts.
- Once complete you can add the Z Axis parts as well as the main X 8080 rail. Watch the Video: Z Axis – Spindle Explosion
- In the CAD Assembly video below, the 4 spacers holding the Stepper motor have now been replaced with a single Z Motor Mount plate using 8 x M5x16mm bolts to secure – 4 from below, 4 from above
XZ Axis Drawings –
NOTE – THERE ARE MULTIPLE DRAWING SHEETS Click the page icon in the top left of this embedded document to view additional sheets
The back halves of spindle mount (at a minimum) must be installed onto the spindle carriage plate before the carriage plate is installed.
X Axis Cad Explosion Video
X Axis Linear Rails
|Part||Description||1000mm Qty||1500mm Qty|
|X Axis Rail||8080 – Tapped Both Ends M8 * 15mm||1||1|
|HG20||Linear Rail – longer of the two for 1000mm mill.||2||2|
|Securing Rail to TeeNutBar through Tslot||M5 x 20 Socket Head Cap Screw||35||50|
|Tee Nut Bar||< 300mm Tnut Bar||7||10|
- When installing the Linear rails, note that they are offset as per the image below.
- Do not install the dust plugs into the bearing rails – this should be left until the end of the build
- Do not tighten any bearing rail bolts until such time as the X-axis belts are being lined up. Only enough so that the bolts do not sit proud of the rail so that they will not catch the bearings when sliding along it.
X Rail Cad Explosion Video
X Rail Assembly Video
Y Plates Build and Gantry Installation
|Parts||Description||1000mm Qty||1500mm Qty|
|SHCS-M6x20||M6 x 20 Socket Head Cap Screws||16||16|
|M6Star||M6 Star External Star Washer||16||16|
|M6Spring||M6 Split/Spring washer||16||16|
|SHCS-M6x20||M5 x 20 Socket Head Cap Screw||35||50|
|M8Star||M8 Star washers||20||20|
|M8Spring||M8 spring washers||20||20|
|SHCS-M8X20-25||M8 x 20 to 25mm Socket Head Cap Screws||20||20|
|HG20||20mm Linear Rail||2||2|
|WC20||WC20 Flanged Linear Bearing Blocks||4||4|
- The remaining 2 x 20mm Linear rails are installed in the top most channel of the main Y rails in the base frame. Leave all bolts loose, tightening only enough to ensure bolt heads are not sitting proud of the rail which will cause them to foul a bearing sliding along the rail.
- Remember Again: Don’t tighten any bolts in the bearing blocks – must remain loose for alignment
- Take note when installing bearing blocks, they should be on the opposite side of the 3 vertical countersinks in the Y plates
- Here we are using a Star washer and a Split Washer on the bearing blocks. The star should be against the alloy plate and the split washer against the head of the bolt. One or the other washer can be left out.
- Don’t tighten up the bearing blocks still – this is the last thing in the build!
Y Plate Cad Explosion video
Y Plate Assembly And Gantry Installation Video
Y End Plate, Pulley Plate, Stepper Plate and Stepper Motor installation.
|XMP||X Motor Plate||1|
|YMP||Y Motor Plate_120mm||2|
|XPP||X Pulley Plate||1|
|YPP||Y Pulley Plate_120mm||2|
|Belt Clamp Bottom and Stepper Motors||M5 x 25 Button Head Cap Screws||22|
|Belt Clamp Top||M4 x 25mm Socket Head Cap Screws||6|
|Some shorter FHCS as several thread bores are shallower||M5 x 16mm Countersunk||10|
|Motor Plates, Pulley Plates||M5 x 20mm Countersunk||18|
|Idler Pulley Axels||M5 x 30 Button/Socket Cap Screws||3|
|Idler External Pulley Spacer||3mm Alloy Spacer – 5mm bore||3|
|Idler Bearings – Two per idler||3×16×5 Bearing 625 2RS||6|
|Idler Internal Spacer||Custom Spacer/Washer||3|
|Stepper Motors||M5 Star Washer||16|
|Stepper Motors||M5 Nylock Nut||16|
- Y Plates have a small M5 Tapped hole that is to be positioned towards the top – as pictured
- Idler pulley plates and motor plates also have an extra hole for a bolt that holds the drag chain support extrusions, these are installed with the hole at the bottom.
Install Idler Bearings with spacer
Attach Idler to Idler Pulley Plates
Install Idler Plates, Motor Plates and Motors
- X Motor requires 20mm screws not 25mm as used on Y,Z,&A motors.
Install Drag Chain Supports
|X Axis Drag Chain Support Rail 2040 T Slot – Longer||1|
|Y Axis Drag Chain Support Rail 2040 Tslot – Shorter||1|
|M5 x 16 Button Head Cap Screws||4|
|Misumi Black Cap 2040||4|
Drag Chain Supports Cad Video
Install Drag Chain Mounts
Drag Chain Mounts Cad Explosion
Drag Chain Installation
|M5 x 12 Button Head Cap Screws||4|
|M5 x 10 Button Head Cap Screws||4|
M5 Pre insertion Tee Nut
- You will need to break and join your drag chain to get the best length, considering bend radius.
- One male and one female drag chain end are required for each section of chain.
- 4 * M4x12 SFHCS Secure the drag chain ends to the mounts.
- 4 * M5x10 or M4x10 SFHCS secure the other ends to the drag chain support extrusions using T-Nuts.
Build Video (2x Speed)
|Y Axis Limit Swithces||M3 x 16mm Socket Head Cap Screws||4|
|X Axis Limit Switches||M3 x 25mm Socket Head Cap Screws||4|
|X Axis Limit Switches||M3 Nylock nut – No longer required||4|
|X Axis Limit Switches||M3 Washer – No Longer Required||4|
|Z Axis Limt Switch||M3 x 16mm Socket Head Cap Screws||2|
- One limits switch has no lever, this is for the Z axis – its triggered by the pillow block bearing case
- The limit switch mounting holes are now tapped m3 so no washer and nut are required
X & Y Limit Switch Cad Explosion
X Limit Switch Cad Explosion
Limit Switch Build Video
Tightening up Y bearings and bearing rails.
The Y-axis bearing rails are to be pulled as high as they can be in the Y rail slots and tightened off. Do not over tighten the bolts, they are only threaded into a thin alloy tee nutbar. There are a lot of these bolts all pulling the Tee nut bar into contact with the inner surface of the t-slot and its this friction which will hold the rail in this place without unnecessary overtightening of these bolts.
Similarly, Pull the gantry high when tightening the bolts in the Y carriage plates bearings. The 8 bolts going into the 2 bearings on each side of the gantry, are to be as low as possible in the slots on the Y carriage plates.
Tightening up X bearings and bearing rails.
Push the X carriage to one side of the machine. Tighten the 8 bearing block bolts in the X Carriage.
When loose, the X-axis bearing rails have some play in the T-slot. They can be moved forward and backwards around 5mm.
Pull the X carriage towards the front of the machine so that it pulls the X bearing rails forward in the t-slot they are secured to. Starting from one end move along the TOP rail (only) securing each screw in the rail. As per the Y bearing rail, no need to over tighten these screws. Keep the X Carriage close and slide it along with you as you move up the X rail. All the while pulling forward on the X Carriage and bearings so that they are positioned towards the front on the machine. Keeping the X carriage close as you move along helps you by having something to pull on to keep the bearing rail in as far forward in its play and also helps to ensure that the rail is being positioned as per the bearings own spacing.
Then work back in the other direction tightening the underside bearing rail screws. Again keeping the carriage close which is all the more important this time. DO NOT pull forward on the carriage, the position of this bottom bearing rail in the t-slot will be set by the bearings in exactly the position that they require.
Install Belt Clamps and Belts
|Parts||Description||1000mm Qty||1500mm Qty|
|Belt Clamp Bottom and Stepper Motors||M5 x 25 Button Head Cap Screws||6||6|
|Belt Clamp Top||M4 x 25mm Socket Head Cap Screws||6||6|
|Belt||Open Loop Belt – meters||7.5||10|
|Belt||Closed loop 275mm T5 Belt||1||1|
- Pull the motors towards in their mounting slots towards the centre of the machine and tighten.
- Leave the top belt clamp top loose with at least 5mm so that you can fit a doubled over belt into it
- back off the screws holding the pulley so the plate is loose with a good 3-5mm of play in the pulley plate
- Install the belt with little slack, but not with too much concern for tension, when the pulley plate screws are tightened tension will pull onto the belt.
- The belt loops over its self and is clamped down between the two belt clamps – as per the image below
- Slide the carriage from end to end to ensure that the belt does not try to run off the motor pulley or the idler pulley. The depth that the motor’s pulley is inserted onto the shaft and the belt is pushed into the clamp may need adjustment. The idler has no adjustment and so will set the standard.
- When retightening the pulley plate take note of the belt tension. It should not be firm but not guitar string tight when the pulley plate is tight. Its a bit difficult to measure so a good test is to pull the gantry forward so the front of Y carriage plate is 300mm from the front of the machine then sit a 600g weight (a full 375mm bottle of beer) on the top of the belt. It should deflect by around 3mm or so. Any tighter and there is a risk of snapping stepper motor shafts, looser and you may end up tightening it later. If you do break something, we will replace it without charge once, with the experience, it wouldn’t happen twice.
- You may need to back off the pulley plate and belt clamp top plate to readjust the belt length/tension several times before being happy.
- The belt clamp top does not need to compress the belt much to gain a very good grip. Don’t over tighten as its difficult to remove later. Always install and remove belt clamp top by turning each screw a little bit at a time. Tightening or loosening one bolt by much more than the other leads to the other getting jammed due to the expanding force of the compressed belt in the clamp. If this happens, squeeze the top and bottom of the clamp together with a pair of plumber’s grips / large set of pliers/vice grips etc, or tap the top plate gently with a hammer.
Belt Clamp Cad Explosion.
Belt Clamp and Belt install Build Video
Wiring and Plumbing
|Parts||Description||1000mm Qty||1500mm Qty|
|VFDCbl||Shielded 4 Core VFD Spindle Cable||5||7|
|HRNS||Stepper Wire Harness||4||4|
|HRNS||Limit Switch Harness||1||1|
|Hose||5mm Water line hose||2x5m||2x5m|
- There are two sets of drag chain. One running with the X-Axis and One Running with the Y.
- All cables running through the X must also travel through Y chain
- You can remove one end of each drag chain and lay it flat to work in cables or more simply remove all the underside clips of the chain and feed through the entire wire bundle as one.
- Tape together each set of 4 motor wires and label at both ends so that they are identifiable later. Do the same with each set of 2 Limit switch wires.
- Ensure there is enough VFD cable (and for water cooled enough coolant line) length for the Z axis to operate. As the Z axis goes down, it will draw more cable down with it and it must still clear the X axis and the Z axis belts and pulleys on the top of the X-axis.
- From the X-axis, all the way back through the X and Y drag chains, the cables required are:
- VFD Cable
- Limit Switch Cable x 3
- Stepper Motor Cable x 4
- Coolant lines if water cooled
- The furthest Y cable (away from the Y cable drag chain) runs down the back of the machine in the T slot of the back support 4040 base extrusion.
- All Cables feeding the machine will end up exiting the Y drag chain at the back of the machine. (Other than the two Y motors which never enter the drag chains.)
Wiring Video 1
Limit Switch Termination
- The limit switches have 3 terminals. Common, Normally Open, Normally Closed
- Generally, we use the common and normally open which are the terminal on the side and the closest terminal to the one on the side.
- Each switch needs two wires, if necessary the common can be shared between any of the switches.
From each switch, one wire goes to the common and one wire to the Normally open.
- There are 4 Wires on each stepper motor.
- The Stepper motors have two coils, and two pairs
- If the wires of any one or more pair are touching each other, the motor will act like a break and be heard to spin by hand. In this way its possible to identify the pairs, if you touch any two wires together and the motor doesn’t become hard to spin, those two are not a pair. When you find a combination of two wires that when joined make the motor difficult to spin, thats a pair – and by default the other two are the second pair.
- The pairs are Red/Blue, and Green/Black.
- Once connected – To identify in the mass of wires coming off the machine which white wire is which motor you can short out one of the pairs on a wire and see which axis becomes difficult to move, then mark this wire so it can be identified when you come to wiring your controller.
- Gecko Driver – (not actually a controller)