Author Topic: Plastic polishing.  (Read 812 times)

Offline Johnny4428

  • SOHC Master
  • Posts: 2085
    • View Profile
Plastic polishing.
« on: June 27, 2021, 09:00:10 AM »
Hi all! I am currently trying without success to improve on inner rear plastic mudguard. I wondered if anybody had tried plastic polishing compounds or any other miracle products? I have tried so far - T cut, Brasso, plastic trim polish, fibreglass polish, toothpaste (extra minty), and the buffing wheel the latter being the most successful. I could paint but they are not painted originally. I know that these are mostly out of sight but I will be annoyed every time I flip up the seat.
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1974 Honda CB550K1. Running resto,
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3

Offline McCabe-Thiele (Ted)

  • Grogu
  • *
  • Posts: 6281
    • View Profile
Re: Plastic polishing.
« Reply #1 on: June 27, 2021, 09:30:46 AM »
On car headlights made from Polycarbonate I have used the following with great success. To remove the top surface I used wet & dry in wet mode starting with 400 grit then progressing to 1500 grit. Then I used Brasso with a buffing kit in my drill. The final finish was to use the clear headlight gel application by Turtle Wax H/L sealant. Typically it took 2-3 hours of work per headlamp but they looked close to perfect. On wrist watches with plastic faces Brasso works
but takes several hours to remove a good scratch. With plastic being quite soft I would use something like Wet & dry for deep scratches if it's to return that gloss look then Auto Glym Clear Bumper Gell works well on automotive black surfaces. Downside is that the finish is not long lasting so needs weekly finishing with a light layer of the clear Gel. Water or uV seem to break it down back to dull.
« Last Edit: June 27, 2021, 09:32:49 AM by Macabethiele (Ted) »
Honda CB500 K1 (new pit dug out ready)
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html

Offline Andrew-S

  • SOHC Pro
  • Posts: 519
    • View Profile
Re: Plastic polishing.
« Reply #2 on: June 27, 2021, 09:34:42 AM »
I've been using this stuff for years on my concours entry TRs, it work for me: https://www.meguiars.com/automotive/products/meguiars-plastx-clear-plastic-cleaner-polish-g12310-10-oz-liquid
1972 UK XL250 K0 Motosport
1976 UK Z900 A4
2018 BMW R1200 GS

Offline Johnny4428

  • SOHC Master
  • Posts: 2085
    • View Profile
Re: Plastic polishing.
« Reply #3 on: June 27, 2021, 05:59:04 PM »
Thanks guys, I had to fine sand to remove quite a few marks that’s why i now need to put shine back on. I will keep trying with different compounds and if all else fails I can polish on buffing mop.
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1974 Honda CB550K1. Running resto,
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3

Offline 4wDaz

  • SOHC Member
  • Posts: 110
    • View Profile
Re: Plastic polishing.
« Reply #4 on: June 27, 2021, 06:10:03 PM »
Have you tried heating it up with a hot air gun ? obviously don’t melt it but it brings all the mould oils to the surface and shines again, mine came out like new.
Genuine And Aftermarket Motorcycle Parts Supplier

Offline Johnny4428

  • SOHC Master
  • Posts: 2085
    • View Profile
Re: Plastic polishing.
« Reply #5 on: June 27, 2021, 10:20:58 PM »
Have you tried heating it up with a hot air gun ? obviously don’t melt it but it brings all the mould oils to the surface and shines again, mine came out like new.
Have not tried heat gun, funny thing though I was just watching this morning a guy on YouTube taking scratches out of plastic trim using heat gun, seemed to work well.


1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1974 Honda CB550K1. Running resto,
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3

Offline philward

  • SOHC Jedi
  • Posts: 2799
    • View Profile
Re: Plastic polishing.
« Reply #6 on: June 28, 2021, 10:38:38 PM »
I used progresively finer emery paper concluding with plastic polishing compound (on a sponge polishing mop)
Current Bikes:-
Honda CB750K2 (1975)
Honda CB500K2 (12/1972)
Honda CR750 Replica (1972)
Honda CB350K0 (1969)
Kawasaki ZZR1100D3 (1995)
Kawasaki ZZR250 (1990) Project (Going on eBay ASAP)

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal