Record Weight

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Record clamps are weights that fit on the spindle of a record player and are designed to ensure the stability of the vinyl for a better tracking. They will help flatten the record to the platter, and by this, keep resonances and unwanted needle motions to a minimum. You will get the most benefit of a record clamp when playing thin, flexible, slightly warped or bowed vinyl, but it won't eliminate warping or bowling completely. This is important when trying to digitally archive your vinyl, and you want to capture the best recording possible.

For today's instructable, we're going to be creating a modified version of the record weight found on: http://www.soundfountain.com/amb/puck.html.

We're going to hand-write some G-Code for a FANUC style controller.

Material: Aluminum 1010

Rough Stock 1.35in OD x 5in Length.

Since I'm not a big believer in bringing phones or cameras into a machine shop while working, a lot of my photos are illustrative in nature, and not work-in-progress images. Be safe, don't be distracted while working with powerful tools!

Step 1: Create Your Model in 2D

Dimensions of the record clamp can be changed to your own preferences. If you want to make it heavier, just adjust the height of the big part. The hole needs to stay deep enough for the spindle. I chose the dimensions as shown in the image above.

Step 2: G Code and M Code Basics

Since we're hand writing our code, it's useful to quickly cover the machine command covered:

Basic Settings:

D Depth of Cut | D0.05

The rate of motion in the direction of cut

F Feedrate | F0.004

The rate of motion in the direction of cut

S Spindle Speed | S3500

The speed that the spindle turns

T Tool |T0202

Tool value (first two digits) and tool compensation values (second two digits)

Set Up Commands:

M08 Coolant On
M09 Coolant Off
G54 Work Offset Positioning #1

Sets a new X0.000 Z0.000 for use. G54-G59 each have their own offset value allowing for easy repetition of procedures.

G42 Cutter Compensation (Right Handed) Compensates for the offset of a tool stored in machine memory.<br>G40 Cutter Compensation OffTurns off compensation for the offset of a tool stored in machine memory.

Basic Motions:

G00 Rapid Motion | G00 X0.000 Z0.000

Move in a straight line at rapid speed. (X, Z of endpoint)

G01 Linear Motion | G01 X1.000 Z0.0750

Move in a straight line at speed from last (F)eedrate. (X, Z of endpoint)

Canned Cycles:

Canned cycles are simplified ways of repeating a set of commands. Instead of having to write out lines of other G commands, a canned cycle automates the process.

G71 Roughing Pass Canned Cycle | G71 P01 Q02 U0.005 W0.005 D.05 F.004

Cut the coordinates found between lines (P) and (Q). Leave (U) and (W) in the X,Z directions for finishing passes. Cut at (D)epth with (F)eedrate

G70 Finish Pass Roughing Cycle | G70 P01 Q02 F.004

Cut the coordinates found between lines (P) and (Q). (F)eedrate

For more help:

https://www.cnccookbook.com/cnc-lathe-gcode-mcode-...

Step 3: Setting Up Tooling and Inserts

This record weight design is fairly simple and straightforward and requires four tools to manufacture. If you look at the code, I have put in a comment block that describes the tool numbers and offsets.

(TOOLING LIST)<br>(TOOL T01 RH 55* CARBIDE TURNING) 
(TOOL T02 CARBIDE INSERT PART OFF) 
(TOOL T03 HSS CENTER DRILL DONE MANUALLY) 
(TOOL T04 L SIZE HSS DRILL DONE MANUALLY)

Tool 01 is a Right Handed 55 degree Carbine Insert Turning Tool.

Tool 02 is a Carbide Insert Part Off Tool.

Tool 03 is a High Speed Steel #5 Center Drill

Tool 04 is a High Speed Steel Jobbers Length L Size Drill

Set the appropriate tool offsets and lengths into the machine for Tools 01 and 02. If you have a controlled tailstock, you can also set up Tool 03 and 04. In my case, I manually performed the first few operations.

Step 4: Loading and Roughing Blank -- Face-Off and Zero

Load your blank into the lathe. I used a 1.35in OD Aluminum 1010 blank. For this project, we will use a three jaw concentric chuck, as our blank is round bar stock. If you have another shape for your bar stock, use the appropriate chuck.

Load the blank into the lathe. My final part length was 1.75in, so to account for some lack of parallelism, and to have some material to remove I measured 1.80in from the part zero. With my desire for some anti-crash headroom, the part zero was .7 inches from the jaws. This means that the surface to be faced off sits 2.5in from the jaw faces.

I used a caliper to determine the appropriate length. I have code that performs a part off operation, so this is not a critical dimension. The code is shown below.

(EXCESS STOCK PART OFF)<br>
T0202 M06 G43 H02 (TOOL 2 PARTING OFF)
G00 G18 G20 G80 G99 (SAFE START)
M08 (COOLANT ON)
S1500 M03 F.002 (SPINDLE SPEED 1500RPM, FEEDRATE .002IN/SEC)
G54 (G54 OFFSETS FROM FRONT OUTSIDE PART EDGE)
G00 X2.000 Z0.000
G00 X2.000 Z-1.755
G01 X2.000 Z-1.755
G01 X0.000 Z-1.755
G00 X2.000 Z-1.755
G00 X2.000 Z0.000
M09 (COOLANT OFF)
M00 (OPTION STOP)

Line by line, the code does the following:

Change to Tool 02, Use Offset 02, Disable Tool Compensation

Safe Start (Ensure no accidental motion)

Coolant On

Spindle Speed to 1500 in CCW direction, Feedrate of .002in/sec

Use offsets from G54

Rapid to 2,0

Rapid to 2,1.755

Cut at 1.755 from part zero

Retract to safe zone

Rapid to 2,1.755

Rapid to 2,0

Coolant Off

Option Stop

The next step is to face off. Facing off removes material from the front of the part to create a surface that is perpendicular to the ways of the lathe -- it creates a flat surface that is parallel to the front faces of the chuck. We need to face off to do our drilling operations.

<p>(FACE OFF TOOLING)</p><p>T0101 M06 G43 H01 (TOOL 1 TOOL CHANGE)</p><p>G50 3500 (SPINDLE SPEED LIMIT)
S2600 M03 (SPINDLE ON)
G54 (G54 OFFSETS FROM SPINDLE SIDE CENTERLINE)
M08</p><p>G00 X2.000 Z-1.750
G01 F.002 X2.000 Z-1.750
G01 X0.000 Z-1.750
G01 X Z-1.750
G01 X0.050 Z-1.750</p><p>G00 X2.000 Z-1.750
G00 X2.000 Z0.000</p><p>M09
M00</p>

This code is fairly similar to the code above. The cutter moves at 1.75 to create a clean surface and removes the excess .050inches left in the Parting Off Operation above.

Step 5: Hand Roughing Blank -- Rough OD Turn (Optional)

My blank was almost the final OD, so I wrote my code for a 1.35in OD blank. If you're using a different size blank, either change the code to account for the different diameter or do a quick rough turn to get to 1.35in OD.

Step 6: Roughing Passes

Time to turn things into shape. We're going to use a set of canned cycles (G70 and G71) to help automate the process. For the roughing passes, we're going to use G71, the roughing canned cycle. G71 takes an outline provided and slices it (much like a 3d printer) to a set of cuts at a specified depth (D) it then automatically follows the contour. This way we don't have to write cycles for each depth.

<pre>(ROUGHING PASSES)<br>
S2600 M03 (SPINDLE ON)
G54 (G54 OFFSETS FROM FRONT PART EDGE)
M08 (COOLANT ON)
G71 P01 Q02 U0.005 W0.005 D.05 F.004
N01 G42 G01 X2.000 Z0.000
G01 X1.200 Z0.000
G01 X1.200 Z-0.200
G01 X0.950 Z-0.200
G01 X0.950 Z-0.750
G01 X1.350 Z-0.750
N02 G01 X1.350 Z-1.750
G40
G01 X1.500 Z-1.750
G00 X1.500 Z0.000
M09
M00

This code does the following (line by line)

Spindle on, CCW at 2600 RPM

Use offsets from G54 value

Turn on Coolant

Run G71 starting at line N01 and ending at line N02. Leave .005in excess from dimensions specified for both X and Z for a finishing pass. The depth of cut is .05 inches. Feedrate of .004in/sec.

N01 - N02 are the coordinates of our profile. Use G53 tool nose compensation.

Turn off tool compensation

Retract to 1.5 at 1.75inches from part zero

Rapid to 1.5,0.

Turn off coolant

Option Stop

Step 7: Finishing Passes

Time to turn things into the final shape. In the previous step, we left .005in in both X and Z for a final finishing pass. To get a better surface finish, we're gonna turn a bit quicker and use the G70 finish canned cycle to remove those last 5 thou. G70 takes an outline provided and then automatically follows the contour. This way we don't have to write cycles for each segment.

(FINISHING PASSESS)<br>S3400 M03 (SPINDLE ON)
M08
G54
G70 P03 Q04 F.001
N03 G42 G01 X2.000 Z0.000
G01 X1.200 Z0.000
G01 X1.200 Z-0.200
G01 X0.950 Z-0.200
G01 X0.950 Z-0.750
G01 X1.350 Z-0.750
N04 G01 X1.350 Z-1.750
G40
M09
M00

Spindle on in CCW direction at 3400 RPM

Coolant On

Use G54 offset values

Run G70 canned cycle. Starting at line N03 and ending at line N04. Feedrate of .001in/sec.

G42 tool nose compensation.

Turn off tool nose compensation

Turn off coolant

Option Stop

Step 8: Manual Drilling Operations

Time to drill.

I don't have code for these operations because they were done manually. First use a center drill to create a spot for drill centering. I ran the cut up the second chamfer on the center drill to create a lazy countersink. This is optional but helps in centering the record weight on the spindle.

I center drilled at 400 RPM.

The second drilling operation is drilling with an L size drill to the final depth. Remember to use a pecking motion (small removals between insertions) to help with chip clearance and heat.

I drilled at 400 RPM

Step 9: Parting Off

Now we've completed making our record puck's profile. However, we need to cut the shape to length. This involves another parting-off operation.

(PART OFF COMPLETED TOOL)

T0202 M06 G43 H02 (TOOL 2 PARTING OFF)
M08 (COOLANT ON)
S1500 M03 F.002
G54 (G54 OFFSETS FROM FRONT OUTSIDE PART EDGE)
G00 X2.000 Z0.000
G00 X1.750 Z0.000
G01 X1.500 Z0.000
G01 X0.000 Z0.000
G01 X1.500 Z0.000
G00 X2.000 Z0.000

M09 (COOLANT OFF)
M00 (OPTION STOP)

Step 10: Flipping Part & Final Operations

Now that we've cut our part, we want to clean up the surface finish with a final finish pass. Because I'm a little lazy and didn't want to set a new zero, we're going to use the lathe to help us re-zero our part.

M05

(DE CHUCK AND FLIP PART AROUND) 
(DO NOT CLAMP CHUCK TIGHTLY) 

M00 

G00 X2.000 Z-2.000 
G01 X0.000 Z-2.000

M00

G01 X0.000 Z-0.005 F0.001

(TIGTHEN CHUCK)<br>
M00<br>

After the M05 stops the spindle, remove the part from the jaws and flip it around. DO NOT CLAMP THE CHUCK! We're going to use the tool to push the part to our new zero.

After a set of motions to move the tool to the centerline of the part, there's another option stop. If everything lines up, the next two lines push the center of the stock to its new zero position very slowly. Once the motion stops, tighten the chuck. We should have left ourselves about 5 thou to remove in a final finish pass, the code for which is below.

<p>T0101 M06 G43 H01 (TOOL 1 TOOL CHANGE) <br>
S3400 M03 (SPINDLE ON) </p><p>G54 (G54 OFFSETS FROM SPINDLE SIDE CENTERLINE) </p><p>M08
G00 X2.000 Z0.000 
G01 F.002 X2.000 Z0.000 
G01 X0.000 Z0.000 
G01 X2.000 Z0.000
M09 
M00</p><p>(PROGRAM ENDING) 
G28 
M09 
M05 
M30 %</p>

Step 11: Finish and Enjoy

If you've followed these steps, you should have one bad*** looking record puck!

Time to figure out your surface finish.

You can:

Anodize for color!

Polish for that bling!

Media Blast to hide your tooling lines (my choice)!

Once you're done, throw on your favorite record, and enjoy the new improved baselines and tracking!

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    Swansong

    11 months ago

    That came out really well! This would make a great gift for someone with a lot of records :)