Let's talk plastics

[cash192t]

Okay, talking plastics...the 192t I have has a cracked center section I just discovered. I have it cleaned up and roughed up. I was going to use the old jb weld plastic epoxy. Does anyone have a better idea? seeing how you have to disassemble the saw to get to it I would rather not do it more than once. Also, heat maybe a factor as it is close to where the muffler goes. thanks

 

[Paul Fithian]

Epoxy doesn't play well with heat. Got a picture of what you are trying to repair?

 

[davidwyby]

How about sanding out dirty scratches and bringing shine back?

 

[nenicu]

Super glue and baking soda worked for me on Stihl plastics

 

[nenicu]

Oil pump side on a ms 230

 

[Paul Fithian]

You can polish nylon with a series of finer sand paper and polishing compound like you would for aluminum or painted surface.

If you really want to make it pop, clear coat it.

 

[legdelimber]

Back in the 1970's early 80's, We used to sandpaper/buff out those hazy plastic gauge lenses on motorcycles.
There was some brand of clear liquid floor wax (danged if I recall the brand now) that did a really nice job of finishing things up.
The wax job usually lasted through the summer and then time to do it again.
I do the same thing to those #%&## plastic headlights on my truck nowdays.

 

[Paul Fithian]

Ran a small experiment with two globs of PL Premium. Both cured for a week in air, then one was immersed in a 40:1 gasoline;oil mix for a week.



Cutaway shows they look the same inside after gasoline exposure:


Both globs felt the same, so this little test shows that a gas/oil mix has no affect on PL Premium.

For something like a fuel tank split at the seam, clean and degrease throughougly, open up the split a bit with a thin cutter, and fill with PL Premium. Clamp together and let sit for a few days before testing.

 

[NateSaw]

You can polish nylon with a series of finer sand paper and polishing compound like you would for aluminum or painted surface.

If you really want to make it pop, clear coat it.

I couldn't find a before picture. But these polished up nice... But, the older plastic is different...
This 461 filter cover was pretty scratched up. I was able to grind the scratches off, but it wouldn't polish past 800 grit. So I can only assume there's a difference in fiber content. I did these saws before finding this awesome thread.

 

[MustangMike]

Ran a small experiment with two globs of PL Premium. Both cured for a week in air, then one was immersed in a 40:1 gasoline;oil mix for a week.
View attachment 397111


Cutaway shows they look the same inside after gasoline exposure:
View attachment 397112

Both globs felt the same, so this little test shows that a gas/oil mix has no affect on PL Premium.

For something like a fuel tank split at the seam, clean and degrease throughougly, open up the split a bit with a thin cutter, and fill with PL Premium. Clamp together and let sit for a few days before testing.

Good info! I would also recommend putting a mesh screen over the seam. I have had wood open up after being glued with PL Premium. Not often, but it has happened.

 

[NateSaw]

You can polish nylon with a series of finer sand paper and polishing compound like you would for aluminum or painted surface.

If you really want to make it pop, clear coat it.

View attachment 397115
I couldn't find a before picture. But these polished up nice... But, the older plastic is different...View attachment 397116
... Because this 461 filter cover I used on this 440 was rough, so I sanded the scratches out. But after say 800 grit, it wouldn't take higher. I'm sure it had a different fiber content. And maybe the newer saws use different plastic too. Didn't think to check the numbers as I hadn't found this cool thread yet.

 

[beaglebriar]

Super glue & baking soda is holding up well on this tank. Been a few weeks of on and off use.. zero leakage.