cuinrearview
Red saw lover
I get asked from time to time about the tools I use to revive scored cylinders. I've cleaned a lot of them now and have had a fair amount of success. When I'm at home I use the flex motor and a mandrel, but occasionally I'll bring one in to work to do on break. I've used a split mandrel in the past and it works great, but when I'm here I just tape a strip of paper to the mandrel and wind it on tight.
Most guys go coarser but I start with 240 grit and end with 500. I spin slowly with little pressure. Let the grit do the work. Here's the 42mm 346 jug I did yesterday.
I'll spin for four or five seconds, then tear the end off of the strip to expose fresh paper. After the strip in the pic above we got to here.
You can still see some aluminum on there. This is the point where I will switch to 500. It seems like the last bit is always near the port. With power tools this is a dangerous point. It would be pretty easy to sand through the plating near the opening. Hand sanding now is the safest way to go. Once you think you're done, spin some red scotchbrite in there.
Any remaining transfer you may have missed will really stick out after the pad is spun in there.
There's still a couple of small spots just below the port. A little more hand sanding with the 500 and another round of scotchbrite and she's ready for service.
Make sure to bathe thoroughly with soap and water. Any leftover grit or scotchbrite dust doesn't play nice with new pistons.
Most dealer shops will not re-use a scored cylinder, so they can be a cheap source for jugs to practice on. Some plating is removed doing this, but it's real hard stuff and applied relatively thinly to the casting. I've not noticed a difference in ring end gap from cleaning a jug up. It is a good idea to check your port champhers afterword, I've seen some rough spots even from the factory. Running around the ports with some 500 grit by hand usually smooths them out.
I mainly work on saws from the 90's and newer. Some things I've observed: Stihl plating is thicker but softer. It's real easy to make a nice finish on them. I've never went through the plating on a Stihl jug. I've had terrible luck with three series Husqvarna jugs with removable transfer covers(359, 350, and 372XT). The plating is hard but very very thin. Hand sanding may be the answer here. Other Husky jugs like the one above don't look quite as nice as Stihls inside when finished, but they both run well. Dolmar plating on the 5100 and 5105 jugs is pretty tough, but I've went through around the port on a couple. Use caution. I hope this helps somebody.
Most guys go coarser but I start with 240 grit and end with 500. I spin slowly with little pressure. Let the grit do the work. Here's the 42mm 346 jug I did yesterday.
I'll spin for four or five seconds, then tear the end off of the strip to expose fresh paper. After the strip in the pic above we got to here.
You can still see some aluminum on there. This is the point where I will switch to 500. It seems like the last bit is always near the port. With power tools this is a dangerous point. It would be pretty easy to sand through the plating near the opening. Hand sanding now is the safest way to go. Once you think you're done, spin some red scotchbrite in there.
Any remaining transfer you may have missed will really stick out after the pad is spun in there.
There's still a couple of small spots just below the port. A little more hand sanding with the 500 and another round of scotchbrite and she's ready for service.
Make sure to bathe thoroughly with soap and water. Any leftover grit or scotchbrite dust doesn't play nice with new pistons.
Most dealer shops will not re-use a scored cylinder, so they can be a cheap source for jugs to practice on. Some plating is removed doing this, but it's real hard stuff and applied relatively thinly to the casting. I've not noticed a difference in ring end gap from cleaning a jug up. It is a good idea to check your port champhers afterword, I've seen some rough spots even from the factory. Running around the ports with some 500 grit by hand usually smooths them out.
I mainly work on saws from the 90's and newer. Some things I've observed: Stihl plating is thicker but softer. It's real easy to make a nice finish on them. I've never went through the plating on a Stihl jug. I've had terrible luck with three series Husqvarna jugs with removable transfer covers(359, 350, and 372XT). The plating is hard but very very thin. Hand sanding may be the answer here. Other Husky jugs like the one above don't look quite as nice as Stihls inside when finished, but they both run well. Dolmar plating on the 5100 and 5105 jugs is pretty tough, but I've went through around the port on a couple. Use caution. I hope this helps somebody.
