Author Topic: Removing Bondo from Plastic  (Read 2929 times)

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Offline flyjsh

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Removing Bondo from Plastic
« on: July 14, 2018, 10:30:23 PM »
Howdy,

Newbie here.  I searched here and the web for some way to remove Bondo from plastic.  The former owner bondoed over the insets for the badges on the side panels.  So, the only two ways of removing Bondo were heat and elbow grease.  Heat will destroy the panels, and I am afraid elbow grease will as well.  Is there another way?

Thanks,
John

Offline PeWe

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Re: Removing Bondo from Plastic
« Reply #1 on: July 14, 2018, 10:39:03 PM »
Maybe old fashioned paint stripper will work. The banned type with methylene cloride /Dichloromethane / Methylene dichloride. Good guy with many names. I'm not sure if it will make the plastic cover brittle.
I know it disolve 2k bondo within a few muinutes.
If it is a CB750, buy new covers.
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Offline dave500

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Re: Removing Bondo from Plastic
« Reply #2 on: July 14, 2018, 10:43:29 PM »
a lot of strippers will melt this old type plastic aswell,i think elbow grease,carefull use of a dremel for the bulk of it?

Offline Yamahawk

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Re: Removing Bondo from Plastic
« Reply #3 on: July 15, 2018, 05:50:42 AM »
I would purchase replacement panels, as has been stated, anything that dissolved Bondo, will dissolve ABS plastic as well. Not too sure the Dremel wouldn't cause undue damage as well, the replacement panels are around $75 a set.
Charlie
1971 CB750K1 (newest bike), 1996 Royal Enfield 500 Bullet (therapy bike), 1981 Yamaha XV920RH, 2006 Kawasaki Concours (retirement bike), 1975 Yamaha RD350 (race bike), 1989 Honda VTR250 Interceptor (race bike), 1986 Kawasaki EX250 Ninja (race bike in progress), 1985 Honda Elite CH250, 1973 Yamaha GT1 80cc, 1974 Yamaha DT360 project bike.

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Offline flyjsh

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Re: Removing Bondo from Plastic
« Reply #4 on: July 15, 2018, 01:49:58 PM »
Thanks for the replies.  I kinda figured replacements were the way to go.  I guess I could always use the old ones to paint up with my "racing" colors.

Offline Bankerdanny

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Re: Removing Bondo from Plastic
« Reply #5 on: July 16, 2018, 07:04:38 AM »
Dremel with brass bristle wire attachment. This will take off the filler and should only do minimal damage to the plastic. You may still need to use some glazing putty to deal with small scratches before paint.
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Current: '76 CB750F. Previous:  '75 CB550F, 2007 Yamaha Vino 125 Scooter, '75 Harley FXE Superglide, '77 GL1000, '77 CB550k, '68 Suzuki K10 80, '68 Yamaha YR2, '69 BMW R69S, '71 Honda SL175, '02 Royal Enfield Bullet 500, '89 Yamaha FJ1200