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Winter Project – Converting Front Axle Drum to Disc

Now that I have my SS tubing I need to know how long to cut each tube. So I setup the car loaded on the springs with a 5° rake and 5° caster angle. Then I measured the distance, center-to-center to each mounting hole. Now I measure each component and what it added to the length of the radius rod or what will be subtracted from the tubing actual length.

FP04_RadiuRodCalculations.jpg
FP04_RadiusRodsCutToLength_03811.jpg

When considering how much to leave on the rod end threads for adjustment I wondered how much it took to change the caster by 3°-4°. So that’s when I decided to measure the change over a significant distance to get an average. Below is what I found.

FP04_RodEndEffectOnCaster_03809.jpg
FP04_RodEndEffectOnCaster_03808.jpg
The average change per turn of a single lower rod end was 0.6°. Now this was adjusting just one rod end, so adjusting the radius rod with both RH and LH threads would theoretically change the caster by 1.2° for each full turn of the radius rod.

[(8.7-3.2) / 9)]*2 = 1.2°

FP04_RodEndEffectOnCasterPerTurn.jpg

Wixey WR365 Digital Angle Gauge
www.amazon.com/gp/product/B0054RJ7VC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
QA-1 1/2" Rod Ends, LH & RH
https://www.summitracing.com/parts/qa1-xml8
https://www.summitracing.com/parts/qa1-xmr8
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I need to polish the Wilwood brake components for the front dics brakes before I spray them with a clear Cerakote. This piece adapts the hub to the disc.

FP05_HubDiscAssembly_03822.jpg

Cerakote - CERAKOTE CLEAR - ALUMINUM
Wilwood Disc Brakes - Rotor Adapter-Drag - 300-3307

I need a fixture to hold the adapter so I can spin it in the drill press while I sand it ….. time to break out the 3D printer. Drew something up in FreeCAD and sent it to the printer. After a few test prints for size, I had the final print done. The final print took 11 hours, test prints took roughly 1.5 hours.

FreeCAD: Your own 3D parametric modeler

I made sure the printed fixture was slightly smaller than the Wilwood adapter OD so I could polish the OD of the adapter. I had to turn down the button head screws so they would not stick out past the OD of the adapter. I really hate broken fingers …..LOL!!!

FP05_FreeCAD_Fixture.jpg
FP05_PolishingWilwoodAdapterPN300-3307_03816.jpg
FP05_3DPrintedAdapter_03815.jpg

FP05_WilwoodDiscAdapter_03813.jpg

Emery Cloth [240, 400, 800, 1000]
https://www.amazon.com/dp/B091B5YQBV?psc=1&ref=ppx_yo2ov_dt_b_product_details

Working on the 2nd adapter I found I only needed to use 800 grit emery cloth to remove the machining marks, then I went straight to the Wet-r-Dry 1000, 1500, 2500 grit paper with WD-40. The 2nd adapter should only take about 2/3 the time of the 1st one. I had to work on the bottom side of the Wilwood adapter while it was in the drill press, so I used a small 6”x3” loaf pan with some WD-40 and dipped a 3/4" strip of Wet-r-Dry paper in it and then pressed it up against the adapter. This way I didn’t make a big mess, although it did sling some WD-40, but I was able to control it.

FP05_AdapterJustBEforeBuffing_03826.jpg
FP05_WilwoodDiscAdapter_03818.jpg

And finally the finished polished adapter !!!

FP05_BeforeAfterPolishedAdapter300-3307_03827.jpg
FP05_BeforeAfterPolishedAdapterCloseup300-3307_03827.jpg
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The shape of the spindles was harder to polish since I couldn’t spin them like I did the brake adapters. The first pic is what I started with, the next two pics are what I used to smooth the surface, cartridge rolls and unitized wheels on my die grinder. Also in the third pic is the 8-inch buffer I just purchased at HF.

FP06_SpindlesBeforePolishing.jpg
FP06_PolishingAbrasives.jpg
FP06_PolishingAndBuffingSetup.jpg
FP06_ChevySpindlesDimensions.jpg
Spindles with King Pins
Speedway 1949-1954 Chevy Car Modified Spindles w/ King Pins

The good thing about the unitized wheels is that as they wear, their shape changes and you can use that to your advantage. You have to be willing to stop working one area and move to another more conducive to the shape you have. You can also take it off the arbor and swap ends giving you a sharp corner again. The cartridge rolls ONLY SPIN one direction.

I know what you’re thinking, two things! First, these are made of steel and they are going to rust. For that I’m going to spray them with clear Cerakote, either MC-5100 or MC-160. We will see how this works out, if it does hold up over time it looks just like chrome, but way cheaper!!! The Cerakote MC-5100 has been on my trailer (aluminum) for over a year now and still looks great.

Secondly, they are hardly visible, the brake rotor and caliper are going to block the view of the spindle. For this I have no good answer …… I guess because I can!

FP06_BuffedSurface_vs_UnitizedWheelSurface_03839.jpg
FP06_BuffedSurface_vs_UnitizedWheelSurface_03843.jpg
FP06_BuffedSurface_vs_UnitizedWheelSurface_03846.jpg

The Harbor Freight buffer has all the power that I need and runs smooth, I'm happy for $140
https://www.harborfreight.com/8-in-stationary-buffer-58827.html

Abrasives
https://www.3m.com/3M/en_US/p/d/b40071661/
http://www.abrasivesupply.com/default.asp
Lehigh Valley Abrasives | Flap Discs, Surface Conditioning Discs, Abrasive Sanding Discs, PSA Disc Rolls, Surface Conditioning Belts and Metalworking Abrasive Sanding Belts
Specialty Abrasives and Tools for Industrial Use - Abrasive Specialties Inc

Want to try out the Unitized Wheels, this kit would be good place to start.
https://www.rshughes.com/p/3M-Scotc...In-3-In-Diameter-Included-18245/048011_18245/
https://www.rshughes.com/p/Standard...Wheel-Variety-Kit-Variety-33027/051115_33027/

Pferd Cartridge Rolls
https://www.amazon.com/dp/B079GJ37R2?psc=1&ref=ppx_yo2ov_dt_b_product_details
https://www.amazon.com/dp/B079GH75T9?psc=1&ref=ppx_yo2ov_dt_b_product_details
 
Wow, Rick! Those came out beautiful!!! Too bad they'll largely be hidden. Oh well, still cool!
 
I can do it for some TIG welding in return?
 
The one inch unitized wheels that I use on my die grinder are NOT only for polishing and shaping parts, but can be used on a bench grinder in a 6 inch wheel. In fact I don't have the normal stone wheel typically seen on a grinder, but a 6" unitized wheel. BUT WAIT, THAT'S NOT ALL IF YOU ORDER IN THE NEXT 30 MINUTES ..... They also have them for angle grinders in a flap wheel. They will make painting your frame a much easier job, when you don't have those those grind marks next to that weld you are trying to fix!

FP07_WeldGrindMarks.jpg
FP07_DadsGromderImotozedWjee;.jpg

Is it time to try something new ???


Sorry, not much I can do about how the website software handles the AMAZON links !

www.amazon.com/44690733-POLINOX-Unmounted-Grinding-Multi-Colour/dp/B00BDIAUZS?crid=1114ZJJBJMWAC&keywords=Pferd+polinox&qid=1664676604&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ==&sprefix=pferd+polinox,aps,90&sr=8-42&linkCode=sl1&tag=makeeveryth06-20&linkId=a153d00705f0838e13e981ea7658b375&language=en_US&ref_=as_li_ss_tl

www.amazon.com/Pferd-Polinox-PNER-W-44690732-115-22-2/dp/B00BDIAUYO?crid=1114ZJJBJMWAC&keywords=Pferd+polinox&qid=1664676604&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ==&sprefix=pferd+polinox,aps,90&sr=8-37&linkCode=sl1&tag=makeeveryth06-20&linkId=111933aaf274f3cdf944080511c215c2&language=en_US&ref_=as_li_ss_tl

www.amazon.com/Pferd-Polinox-PNER-MW-44691442-7513-6/dp/B00BDIB688?crid=1114ZJJBJMWAC&keywords=Pferd+polinox&qid=1664676604&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ==&sprefix=pferd+polinox,aps,90&sr=8-22&linkCode=sl1&tag=makeeveryth06-20&linkId=8e17e8a64b1c9e09cba5f59cee05b9a1&language=en_US&ref_=as_li_ss_tl

www.amazon.com/48422-Non-Woven-Abrasive-Unitized-Medium-Soft/dp/B0742M8QZ9?crid=1114ZJJBJMWAC&keywords=Pferd+polinox&qid=1664676604&qu=eyJxc2MiOiIwLjAwIiwicXNhIjoiMC4wMCIsInFzcCI6IjAuMDAifQ==&sprefix=pferd+polinox,aps,90&sr=8-18&ufe=app_do:amzn1.fos.006c50ae-5d4c-4777-9bc0-4513d670b6bc&linkCode=sl1&tag=makeeveryth06-20&linkId=17102ed3f274eb0d075ea2092e292bfb&language=en_US&ref_=as_li_ss_tl
 
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I've found it confusing when trying to figure out what Unitized Wheel (UW) I needed and where to order it from. They have a rating that determine their hardness (Density #), Material and Grade. It's all coded into an abbreviation used in the description many times such as "2SMED".

FP08_UnitizedWheelGuide.jpg
FP08_AbrasivesMaterials.jpg
For all the UW I've used so far I have needed the "936 Mandrel". It's quick and easy to change out the wheel by hand. For some of the harder densities, you might need a tool to hold the collet. If you want to use some of the 2-3 inch UW that are ~ 1/4" wide to dress some welds, then you will want the "990 Mandrel".

FP08_UnitizedMandrels.jpg

My recommendation to get started would be the two highlighted in GREEN below. Use a cartridge roll before you get to the 6A MED.

FP08_UnitizedWheelPartNumbers.jpg

There are certainly lots more possibilities, see below. I've used 1/8" hole and I believe the 1/4" might also work with the 936 mandrel. I ordered some 1/4" wide UW with a 1/4" hole to try.

FP08_UnitizedWheelPartNumbers01.jpg

I ordered from Grove Industrial today, they charged $23 for S*H, but no tax outside of Texas.
Home | Groves Industrial
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G'Day Indy, thanks for the info about these wheels/discs. Will have to look into the availability local to me.
 
Just checked on the PFERD Aust website, 125mm disc for 5" grinder. $146.65 Ea!! No thanks!

What size are you looking at? Do you have a link?

The UW that I'm using on the die grinder are 1"x1" and cost $6-$9 each. I used probably 3 for those spindles above. The softer they are the faster they are sued up.

This is the most expensive UW I bought today, it's 6 in Dia, 1 in Center Hole, 1/2 in W Face, Fine Grade, Silicon Carbide for $45, it will go on my bench grinder at some point.I've had the one on my bench grinder seen above for years now.

It's easy to find reducers to adapt to any size shaft from the 1" ID.

upload_2023-4-22_19-10-54.png

These looked good for dressing welds and cost $7. Wheel, 2 in Dia Wheel, 1/4 in Center Hole, 3/4 in W Face, Medium Grade, Ceramic Abrasive.

upload_2023-4-22_19-14-6.png

Do check out the clearance items if you go to Grove Industrial, be prepared there are over a 100 pages.
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You could bring one by and try it at my place.
 
Will do. I made progress in the shop today. I will do some stainless practice and bring some coupons by to see how they polish up and see if I need more practice before I do your radius rods. I’m pretty confident with the rosette welds we should be successful. You about ready?
 
Have looked at another supplier and their prices are much more home workshop friendly. The PFERD prices shocked me! They make good gear, but not THAT good.
 

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