Bending Bent Cylinder Fins

[Gvsu141]

I have a nice running 2150 that has some seriously bent cylinder fins on the OEM 45mm cylinder. Saw runs great, and it doesn't seem to impact operation.

Is there any chance at bending these back? I was thinking about heating them up good with a torch and giving it a shot. This saw is getting the 346xp treatment, but I want to use this cylinder for another saw. This 45mm runs pretty strong.

 

[ammoaddict]

Dang. You weren't kidding about seriously bent. How in the heck did they do that?

 

[Junk Meister]

I visualize those fins about the same as a bent brass antenna on the old cars. I read that the cylinders are aluminum so they can be welded. ( they bend one way break the other way) just need to be aware heat can mess up the Plating in the cylinder bore. IF the top hat fits with the bent fins I would try to resist the "OCD" impulse to straighten the fins. I will watch this tread for a chance to glean more insight.

 

[Gvsu141]

Dang. You weren't kidding about seriously bent. How in the heck did they do that?

I have no idea. You would never know by looking at it. It cleaned up nice. It just had a popped out AV mount screw when I got it.

 

[Gvsu141]

( they bend one way break the other way) just need to be aware heat can mess up the Plating in the cylinder bore. IF the top hat fits with the bent fins I would try to resist the "OCD" impulse to straighten the fins.

That's my fear also. I may just have to use as-is, as the bore is mint. I have a 350 that is in OK shape with an aftermarket cylinder I was going to throw this on, likely to sell.

 

[srcarr52]

Heat them up, don't try to bend them cold as they'll snap right off.

 

[drf256]

I’d leave ‘em alone. Better there than not at all.

 

[Junk Meister]

Heat them up, don't try to bend them cold as they'll snap right off.

Thanks to the O.P. for this thread.
Thanks for the insight . Is there a temp range and or procedure to heat this Like heat only the fin to be tweaked , heat all of the cylinder then flex the fin? melting/heat stick for what temp? I have a 2186 needing some help but my bent fin is on the opposite side and the cover doesn't have much to set on. I think you posted that the cylinders were Aluminum not magnesium (some time ago). The 2186 is apart in the box for now.

 

[beaglebriar]

Impressive that they bent that far without snapping. I’ve never been that lucky.

 

[hacskaroly]

Is there a temp range and or procedure to heat this Like heat only the fin to be tweaked

Do you have or can you get a hold of a junk cylinder? If so, then you can heat and bend all you want to see how it goes and what all happens without screwing up your working (but bent) cylinder. If you don't have a test cylinder handy, ask a friend if you can borrow their saw...

 

[Gvsu141]

Do you have or can you get a hold of a junk cylinder?

I may just do this. I have a crappy aftermarket one I could play with. It will be a week or two before I can get to it though

 

[srcarr52]

I’d leave ‘em alone. Better there than not at all.

I'm with doc here, that top fin already has a crack formed in it.

 

[drf256]

I'm with doc here, that top fin already has a crack formed in it.

Bingo. You know there’s no way it’s gonna stay on there solid. Loominum don’t like bending.

 

[Boomer2230]

Just leave it or it's going to snap if you heat it and try and bend it back.

That probably got dropped when hot and bent it to begin with.

Once you bend a cast aluminum, it becomes brittle.
You would almost have to get it really hot. Almost to its melting point for it to work right.

 

[300whisper]

Don't ever bend you cooling fins. Ever!

 

[SEGARE]

Leave them alone. As is, they are providing some measure of heat transfer and cooling.

 

[David Young]

Lee vumm

They are still functional if they are missing they are not.

Either a tree or more likely a run over.