Snap Fit Tone Ring Assembly

Version 20 (J. Simmons, 07/29/2018 01:05 am) → Version 21/22 (J. Simmons, 07/29/2018 10:39 pm)

h1. Tone Ring Half Assembly

{{>toc}}

h2. Tools

* Holoseat Test Stand
* Magnetic Compass
* Soldering Iron with clean wide flat tip
* Heat proof matt
* Spacer TODO - get dimensions

h2. Materials

* Instant/super glue (prefer Loctite Super Glue Ultragel Control)
* (1) 18PTR-01: Snap Fit 18 Pole Tone Ring Base
* (1) 18PTR-02: Snap Fit 18 Pole Tone Ring Cover
* (18) 18PTR-03: N52 3/16" x 3/16" Neodymium Cylinder Magnets
* (1) 18PTR-04: M3 x 0.5 mm Thread Size, 3.8 mm Installed Length Heat-Set Inserts for Plastics
* (2) HS-07: 18-8 Stainless Steel Flanged Button Head Screw, M3 x 0.5 mm Thread Size, 5 mm Long
* (1) HS-08: 49 mm 2mm Hex Tip Key L Wrench with short arm

Note: The final build requires (2) *HS-03: 18 Pole Tone Ring Halves* as detailed in Step 6.

h2. Safety Issues

* Use safety glasses when working with small, high powered magnets to avoid eye injury from flying magnets
* Be sure to maintain physical control of magnets (those being placed and those already placed) to avoid flying magnets

h2. Product

HS-03: 18 Pole Tone Ring Half

h2. Procedure

h3. 1. Place Heat-Set Insert

# Place the *18PTR-01: Snap Fit 18 Pole Tone Ring Base* on heat proof mat with the spacer supporting the overhanging tab
!step1.1-sm.jpg!
# Place *18PTR-04: M3 x 0.5 mm Thread Size, 3.8 mm Installed Length Heat-Set Inserts for Plastics* face up into the the hole in the *Tone Ring Base* (when setting the insert, try press fitting it into place to seat it prior to later steps)
!step1.2a-sm.png!:https://www.mcmaster.com/#94180A331
!step1.2b-sm.jpg!
# Set Soldering Iron to 350 Celsius and wait for it to reach temperature
# Use the flat of the soldering iron tip to apply gentle pressure to the *Heat-set Insert* until it melts into the hole and sits flush. Take care not to twist or shift the insert.
{{youtube(UdDcJpsXWKc)}} *INSERT VID*

h3. 2. Place Initial Magnet

# Select 1 *18PTR-03: N52 3/16" x 3/16" Neodymium Cylinder Magnet*
# Find the *Magnet's* south pole using the magnetic compass (this is the pole which attracts the north/red indicator - see references)
!step2.2-sm.jpg!
# Align the *Base* so that the tab is closer to you than the slot
!step2.3-sm.jpg!
# Apply super glue to the half magnet slot away from you and insert the magnet so that the south pole identified above faces out in the *Tone Ring*; take care that the *Magnet* is flat in its slot and hold it in place for 60 seconds
!step2.4-sm.jpg!
# Wait 15 min

h3. 3. Place Remaining Magnets

# Select another magnet and find its polarity by placing it along the outside edge so that it becomes attracted to the previous magnet
!step3.1-sm.jpg!
# Rotate the magnet from the previous step 180 degrees (so that the pole attracted to the previous magnet is facing out to create a pole pair) and place it in the next slot in the base
!step3.2-sm.jpg!
# Repeat the previous two steps until the tone ring is fully populated
!step3.3-sm.jpg!

h3. 4. Verify Magnet Placement

Note: You will need (2) in progress *HS-03: 18 Pole Tone Ring Halves* for testing

# Set up the Holoseat Test Stand
## Ensure the calibrated sensor is attached to the sensor controller
## Ensure the power and USB connections are all configured according to the test stand operating instructions
## Join (2) in progress *HS-03: 18 Pole Tone Ring Halves* onto the tone ring adapter
!step4.1-sm.jpg!
# Run tone ring test(s)
*INSERT TEST VID*
!step4.2b-sm.png!
# Remove the tone ring halves from the tone ring adapter

h3. 5. Fix Cover to Base

# Apply super glue to the *Base* as shown below
!step5.1_marked-sm.jpg!
# Place *18PTR-02: Snap Fit 18 Pole Tone Ring Cover* onto *Base*
# Press the *Top* firmly onto the base for 1 minute
!step5.3-sm.jpg!
# Wait 1 hour

h3. 6. Verify Fit

Note: You will need (2) in progress *HS-03: 18 Pole Tone Ring Halves* which going forward will be considered a complete set

# Take 2 *Tone Ring Halves*, insert the tabs from each into the slots of the other, and push until they form a single disc (there may be a click as the exposed magnets seat into the other half)
# Check the alignment of the screw hole on each half with the *Heat-set Insert* to verify the *HS-07: 18-8 Stainless Steel Flanged Button Head Screw, M3 x 0.5 mm Thread Size, 5 mm Long* will set properly
## If the alignment is good move on to the next step
!step6.2-sm.jpg!
## Otherwise, disassemble the 2 halves and use the soldering iron to correct the alignment (retest fit as necessary)
# Use the *HS-08: 49 mm 2mm Hex Tip Key L Wrench with short arm* to screw in the two *Screws* to complete the tone ring assembly
## If the alignment is good the assembly is complete
!step6.3-sm.jpg!
## Otherwise, disassemble the 2 halves and use the soldering iron to correct the alignment (retest fit as necessary)

h2. References

* "What Are Magnetic Poles and How to Identify Them":https://www.apexmagnets.com/news-how-tos/what-are-magnetic-poles-and-how-to-identify-them/
* "Reading a Compass":http://www.compassdude.com/compass-reading.php