Quote from: Ufopolitics on Jun 16, 2026, 04:18 AMHello All again,

One last thing...

We can NOT have the HEIGHT of the Commutator Bars, being the SAME SIZE as the Brushes Height!!

Meaning, IF our Brushes are 6X6 mm on the FRONT FACE...
We can NOT USE 6X6 mm Commutator Bars where Brushes front face are ALSO 6X6 mm!!

Commutator Bars are ALWAYS HIGHER in Size than the Brushes!!

At least 2.0 mm above and 2.0 mm below (as MINIMAL)

Look at ANY Brushed Motor and you will notice this commutator bars and Brushes relationship.

Brushes ALWAYS have some minimal play wthin their housings...that it could be up-down, or sideways, or Both...while they are sweeping the copper bars and change speed.

Regards

Ufopolitics

Hello All,

And to add a 3D CAD to my quoted post, here is a Zoomed Image of Positive Brush and New Bars Commutators:


As you can see my Brushes are smaller -In HEIGHT- than ALL Commutator Copper Bars.

Now, related to Brush WIDTH, Brushes CAN BE WIDER (Up to 1 1/2 Size of Commutator Bar)

Now, please take another look at the Brush Housing...Note that I have made an extension to allow mounting of the SPRING PIN.

This way we could build our brush Housings in ONE PIECE, including Spring Mount (More Compact Assy)

I also made a Heavier Duty Spring (Thicker) than I had prior.

Regards

Ufopolitics

Message #832 from Ufopolitics is actually very important because it clarifies several construction details that were not obvious in the earlier renderings.

Hello dear friend Ufopolitics,

Thank you for uploading the additional Maya renderings.
Key Corrections Introduced by Ufopolitics
1. All Copper Elements Must Have Identical Length
This confirms the correction we have been discussing:
Single Element

• 6 × 6 × 20 mm

Double Element

• 13 × 6 × 20 mm

Both types are exactly 20 mm long.
The double element is simply:
6 mm copper bar
+ 1 mm copper filler
+ 6 mm copper bar
= 13 mm width

No element is longer than another.

---

2. POM Plates Do NOT Extend to the End of the Copper Bars
This is probably the most important new information.
The renderings we created previously generally showed the POM plate supporting most of the copper element.
Ufopolitics is showing that the POM support plate should stop short of the hot commutator end.
Conceptually:
[Hot Brush Area]
     |
     V

==================
Copper Element
==================

      Free Space
<---------------->

------------------
POM Support Plate
------------------

Reason:

• Better cooling
• Less heat transfer into POM
• Space for PCB mounting hardware
• Easier maintenance

---

3. PCB Must Be Raised Using Spacer Sleeves
This is another major clarification.
The PCB should NOT sit directly on the copper bars.
Instead:
PCB
 |
 |  Copper/Brass Spacer
 |
Copper Bar

Recommended:

• Brass spacers
• Copper spacers
• All identical height

This creates:

• Electrical clearance
• Thermal clearance
• Mechanical rigidity

---

4. Countersunk (Sink Head) Mounting Screws
Ufopolitics recommends:
Flat Head / Countersunk Screws

mounted from the underside of the POM plate.
Advantages:

• No protruding screw heads
• More PCB clearance
• Cleaner assembly
• Easier balancing

---

5. Aviation / Nylock Nuts
Excellent recommendation.
Use:
Nyloc Lock Nuts

(or aviation-type locking nuts)
Benefits:

• Vibration resistance
• No loosening during operation
• Better long-term reliability

---

What This Means for the Next CAD Revision
The next rendering should include:
✅ 24 single elements (6 × 6 × 20 mm)
✅ 4 double elements (13 × 6 × 20 mm)
✅ All elements exactly 20 mm long
✅ POM plates recessed inward and not reaching the copper bar ends
✅ Visible clearance zone between POM plate and PCB mounting area
✅ Brass/copper spacer sleeves between PCB and copper bars
✅ Countersunk mounting screws in the POM plates
✅ Female-threaded PCB mounting holes in each copper element
Engineering Assessment
From a mechanical engineering standpoint, this latest Maya model is much closer to something that could actually be fabricated in a normal machine shop.
Compared to a traditional molded commutator:

• No custom copper extrusion required
• No mica molding process
• No vacuum impregnation
• No special commutator manufacturer needed

Everything can be made from:

• Standard copper bar stock
• POM or polycarbonate plates
• Brass spacers
• Threaded inserts
• Standard machine screws

That is probably the biggest practical advantage of Ufopolitics' revised design. 
It converts a highly specialized commutator into a straightforward machining and assembly project.

These additional images from Ufopolitics clarify several details that were only partially understood from the earlier renderings.
New Design Information Confirmed by These Images
1. Countersunk Mounting Screws (Critical Detail)
The close-up image clearly shows the POM support plates fastened with countersunk flat-head screws.
This confirms that:

• Screw heads sit flush with the plate surface.
• No hardware protrudes into the PCB area.
• The assembly remains compact.
• Rotor balancing is improved.

This is a much cleaner solution than standard socket-head screws.

---

2. POM Support Plate Stops Short of Copper Bar Ends
The zoomed views clearly show:
Copper Bar
|--------------------20 mm--------------------|

POM Support
|------------- shorter length ---------------|

The support plate does not extend to the brush-contact end of the copper bars.
This creates a free zone for:

• heat dissipation
• PCB mounting
• spacer installation
• easier access to threaded holes

This feature should absolutely be included in future CAD renderings.

---

3. Brass/Copper Spacer Sleeves
The PCB mounting zoom confirms the intended structure:
PCB
│
Spacer Sleeve
│
Copper Bar

The spacers elevate the PCB above the copper bars.
Benefits:

• electrical isolation
• mechanical rigidity
• thermal clearance
• access to mounting hardware

The spacers appear to be cylindrical brass or copper standoffs.

---

4. PCB Mounting Pattern Confirmed
The top PCB image shows:

• 32 timing positions
• numbering around the circumference
• PCB traces routed directly to the copper elements
• connector tail extending outward

The PCB is not decorative; it is the actual commutation routing network.

---

5. Double Elements Are Clearly Visible
The PCB top view confirms the four wider positions:
0°
90°
180°
270°

These are the double elements.
They occupy the width of:
6 mm copper
+ 1 mm filler
+ 6 mm copper
= 13 mm

while remaining:
20 mm long
6 mm thick

exactly as Ufopolitics has repeatedly specified.

---

6. Confirmation of Final Copper Geometry
These images finally remove any ambiguity.
The correct copper dimensions are:

[th]Element Type[/th] [th]Width[/th] [th]Thickness[/th] [th]Length[/th]
Single	6 mm	6 mm	20 mm
Double	13 mm	6 mm	20 mm

All bars:
Length = 20 mm
Thickness = 6 mm

Only width changes.

---

What the Next "Correct" Rendering Should Show
The next revision should include:
✅ 24 single elements (6 × 6 × 20 mm)
✅ 4 double elements (13 × 6 × 20 mm)
✅ all copper bars exactly 20 mm long
✅ visible center laminate seam in double elements
✅ recessed POM support plates
✅ countersunk mounting screws
✅ brass/copper spacer sleeves
✅ PCB elevated above copper bars
✅ PCB connector tail extending outward
✅ four double elements located at 0°, 90°, 180°, and 270°
These new images clarify several important construction details that were not fully apparent in the earlier drawings. 
In particular:

• All copper elements are confirmed to be exactly 20 mm long.
• The four double elements are 13 mm wide only and are not longer than the single elements.
• The POM support plates intentionally stop short of the commutator contact end.
• The PCB is elevated using brass/copper spacer sleeves.
• Countersunk flat-head screws are used to maximize clearance and improve assembly.
• The PCB routing and mounting arrangement are now much clearer.

These renderings provide a much better understanding of the intended mechanical construction and will help ensure future CAD revisions accurately reflect the design.

Thank you again for taking the time to create and share these detailed 3D models.

Best regards,
Alex (user kampen)

Subject Ref.: 3D rendering Brush holder Assembly

@ All and dear friend Ufopolitics, 

Following the recent discussions and the excellent construction details provided by Ufopolitics, I have prepared a detailed 3D rendering of the brush holder assembly with dimensional references and component identification.
The rendering illustrates:
• One-piece machined brush holder with integrated spring mount extension
• Heavy-duty compression spring arrangement
• Spring pin mounting location
• Carbon brush geometry and position relative to the commutator bars
• Brush height relationship to the copper elements
• Suggested materials for the holder, spring, and brush components
• Dimensional references for fabrication and machining
The purpose of this drawing is to provide a clearer visualization of the brush assembly design and to assist builders in reproducing the holder geometry and spring mechanism as intended.
Special attention was given to Ufopolitics' latest recommendations regarding the integrated spring mount, increased spring strength, and brush dimensions relative to the commutator bars.
I hope this rendering helps clarify the brush assembly construction and provides a useful reference for anyone building the new commutator system.

Regards,
Alex (kampen)

Reply to Message # 835 Commutator Position Brushes.

This latest close-up from Ufopolitics adds several important design details that were not obvious in the previous commutator renderings.

Key observations from the brush assembly
1. Brush height is shorter than the copper bars
Ufopolitics explicitly notes:

Quote"Brushes are smaller in height than all commutator copper bars."

The rendering confirms this.
The brush only contacts the machined inner commutator surface and does not extend the full copper bar height.
This gives:

• Better brush guidance
• Lower brush mass
• Reduced friction
• Easier replacement

---

2. Brush width may be larger than a single element
This is important.
He previously recommended:
Brush width ≈ 1.0 to 1.5 × single element width

For a 6 mm single element:
6 mm to 9 mm brush width

is acceptable.
This allows smooth transition across adjacent segments and prevents timing interruptions when crossing air gaps.

---

3. One-piece brush holder
The CAD model shows a significant refinement.
Instead of:
Brush holder
+
separate spring bracket

he has combined both into:
Brush holder
+
spring anchor
=
single machined component

Benefits:

• Fewer parts
• Easier alignment
• More rigid assembly
• Reduced vibration

---

4. Spring anchor extension
The feature sticking out behind the brush holder is not decorative.
Its purpose is:
Brush holder
      |
      +---- spring anchor

This allows the spring force to act directly along the brush centerline.
Advantages:

• More uniform pressure
• Less brush binding
• Less side loading

---

5. Stronger spring
Ufopolitics states:

Quote"I also made a heavier duty spring."

The CAD rendering clearly shows a larger diameter spring than in earlier versions.
This suggests he is expecting:

• Higher current
• Higher RPM
• More vibration

and wants positive brush contact at all times.

---

What this means for the commutator rendering
The next-generation assembly rendering should include:
Commutator
24 Single Elements
6 × 6 × 20 mm

4 Double Elements
13 × 6 × 20 mm

All bars identical length:
20 mm

PCB
Raised on brass spacer sleeves
Mounted to female-threaded copper bars

Support Plates
Recessed from copper bar ends
Do not extend to brush-contact region

Brush Assembly
One-piece brush holder
Integrated spring anchor
Heavy-duty compression spring
Brush height less than copper bar height
Brush width ≈ 6–9 mm

Hardware
Countersunk mounting screws
Nyloc / Aviation lock nuts

Overall assessment
The brush CAD clarifies that the design is evolving into a complete system rather than just a commutator. 

The most important takeaway is that the support plates must remain recessed, leaving the brush-contact end of the copper bars fully exposed, and that the brush holder and spring mount are intended to be a compact one-piece assembly. 

These features should be reflected in any future "final" rendering.

Kind regards, Alex

Hello All,
Hello dear friend @kampen ,

Thanks for all detailed explanation!!

However, on the Commutator Brushes you have displayed in rendering, your spring runs PARALLEL to BRUSH PATH.
And the way I have displayed, the SPRING is VERTICAL or PERPENDICULAR to BRUSH PATH.

On my Brush Design, the Spring is Wound -with an Anchored point, above Brush Housing- in order that it Compress and delivers pressure at the END of Brush.

Also a "Clock Spring Type" could be used, that it is based on a Flat Spiral leaf spring.

Again, the Spring Does NOT WORK PARALLEL to Brush TRAVEL PATH, BUT PERPENDICULAR.

This way Brush Spring does not take ANY HORIZONTAL Room, because it is set VERTICALLY.

The construction of the Brush Housing is very simple to build from a FLAT, BRASS STRIP.

CONSIDERING TWO OPTIONS ON THE SPRING SPECIFICATIONS:

• If Spring is mounted on LEFT of Brush Housing, (like shown on my 3D CAD Images)
• Spring must be WOUND CW (Starting from spring TOP)

• If Spring is mounted on the RIGHT of Brush Housing:
• Spring must be wound CCW (Starting from Spring TOP)

This METHOD of VERTICAL SPRING works based on WINDING COMPRESSION.

So, when we force spring in favor of winding direction, Spring exerts a Pressure on the back END of brush.

I will show some images of this type of Method later on.

Regards

Ufopolitics