Honing a Shihl Cylinder. What's the proper grit?

[Scooterbum]

1/2" or so drill bit, grab some duct tape and a hunk of scotchbrite.Tape the scotchbrite to the bit and wrap it. Run this in and out a few times is all that is needed.
Hones do more damage then good on plated cylinders of any kind.

As far as that you tube video? Ya' think he's tryin' ta' sell hones? Maybe ? Just maybe?

 

[etbrown4]

Question to ZeroJunk: The 6-8 seconds total honing approach, sounds like a better approach to scratched cylinders, than anything longer than that! What type of hone did you use successfully? Flat stones or round? What grit?

Question to russhd1997, one.man.band, rms61moparman, and RTK among others referring to Nikasil: Interested to know if pretty much all Stihl and other best known brands of saws have used Nikasil plating over the last 15-20 years. Is there any way you can tell if it is or isn't Nikasil?

Question to RTK: You mention that it takes a diamond hone to cut a cylinder plated with Nikasil. Curious to learn what effect you or others might possibly have observed from an aluminum oxide hone when lightly applied to Nikasil.

Thanks for all the great contributions! To be continued.......

 

[chopperfreak2k1]

As far as that you tube video? Ya' think he's tryin' ta' sell hones? Maybe ? Just maybe?

i was just gonna say that

 

[blsnelling]

The fine grit ball hones that Baileys sells are VERY handy when trying to save a cylinder. I remove the transfer with acid and wet/dry sandpaper by hand. But there are always scratches left over. The hone does a very nice job of finishing it out. I might add that it takes a LOT more to go through the NiSi than many of you seem to think. I've not done it yet. My process is to submerge the cylinder and hone in my parts washer filled with mineral spirits.

Now, with that said, I do not recommend honing a good cylinder when replacing the rings. On the other hand, I know some guys that port finish every job with a quick hone. It may not be necessary, but I don't think it's near as bad as many of you are making out. JMHO

 

[rupedoggy]

Even JBJ doesn't hone Nikasil cylinders.

Does that stand for Bon Jovi or Jacob "B" Jenks?

 

[Jacob J.]

Does that stand for Bon Jovi or Jacob "B" Jenks?

Either/or, since my middle name is "Badmutha."

I have to admit though, I'm a lot uglier than Mr. Jovi, both physically and spiritually.

 

[Hillbilly Rick]

Even JBJ doesn't hone Nikasil cylinders.

That pic scared the hell outta me, JBJ with a chainsaw:hmm3grin2orange:
I plan on doing my own CS work and this is info I need, thanks for the thread.

 

[ZeroJunk]

Question to ZeroJunk: The 6-8 seconds total honing approach, sounds like a better approach to scratched cylinders, than anything longer than that! What type of hone did you use successfully? Flat stones or round? What grit?

I use the ball hones like in the video. I get the transfer out as best I can with acid. Then I finish it off with the ball hone and then throw the cylinder in the dish washer to clean it up.

I have some saws nearby that I can keep up with that have been used quite extensively and they are still running strong.

 

[etbrown4]

What acid do you use?

Do you know the grit of the ball hone? Thanks

 

[rbmopar]

I don't think there is much doubt that nearly every saw manufacturer hones the final few thousandths prior to final assembly, and assuming that's a fact, what the diff, as long as we only enlarge the bore maybe a quarter thousandth?

I seriously doubt manufacturers "hone" the last "few" thousanths as you state, and I do not accept it as fact. The plating is hardly that thick. The bore is sized accurately before plating, and then the plating is applied very eveny. The final honing they do is a hell of a lot more precise than throwing a ball hone in a drill and hoping for the best. If you are set on honing a cylinder, go for it, no one is going to stop you. If you ruin it just remember EVERYONE told you not hone a good cylinder, and a few use it to save a scored one. There is little or nothing to gain, and much to loose. my 2c

 

[bigmoose]

What is the hardness of the nic coating in the cylinders?If it takes some king of diamond coated cutter to cut it then how does the silocone carbide or aluminum carbide balls of the damage it?I think the ball hones are avaliable in different grits.I dont know about baileys but they are from other suppliers.

 

[RTK]

What is the hardness of the nic coating in the cylinders?If it takes some king of diamond coated cutter to cut it then how does the silocone carbide or aluminum carbide balls of the damage it?I think the ball hones are avaliable in different grits.I dont know about baileys but they are from other suppliers.

You "can" sometimes chip the coatings around the ports with a ball hone, then the cylinder is toast. Since true Nikasil is extremely hard and not worn much by the rings there is no need to hone, it retains much of it's original state, that is the beauty of it.

 

[bigmoose]

I see where that could happen.How do porters avoid this when they cut new ports?Do they bevel the edges of the port?

 

[RTK]

They are very careful

 

[rbmopar]

Here are some pic's of what a ball hone does to a plated two stroke cylinder that someone was trying to "fix". Pretty special stuff by anybody's standards. Will the saw run? Sure. But not as long as if the genius had left the hone in the tool box.


View attachment 212972
View attachment 212973

 

[blsnelling]

A ball hone will not do that if used properly. I have done a fair amount of honing in problem cylinders before, and never had one damaged like that. Is it possible? Absolutely. But it would be incorrect to lead others to believe that this is normal.

 

[ZeroJunk]

As far as honing a damaged cylinder I honed one on a 046 a few years ago until the plating on both sides of the ports was missing for probably an eighth of an inch. Stuck a piston in it and gave it to a friend of mine who sells firewood. He says the saw still runs fantastic. I tried to buy it from him to put a BB in and he won't sell it back to me.

Some of you need to try some of this stuff and report back the resulting disaster.

There is a difference between getting a saw back in operation cheap and making it like new. There is a big difference in cost.

I fix a lot of saws cheap, and I have a driveway warranty. Everybody thinks it is better than junking the saw or paying more than it's worth to have it fixed.

Interestingly enough they seem to hold up fine.

 

[ZeroJunk]

A ball hone will not do that if used properly. I have done a fair amount of honing in problem cylinders before, and never had one damaged like that. Is it possible? Absolutely. But it would be incorrect to lead others to believe that this is normal.

I just saw those photos and I can tell you that yes it will do it, but you have to stay in there a long, long time. Certainly more than anybody with any common sense would unless they were trying to hone out some very deep damage.

 

[blsnelling]

I just saw those photos and I can tell you that yes it will do it, but you have to stay in there a long, long time. Certainly more than anybody with any common sense would unless they were trying to hone out some very deep damage.

Exactly.

 

[blsnelling]

This is the result of a properly honed cylinder. The remain scratches cannot be felt. No bare port edges here.

Here's another.

This one did not clean up as nicely. Since it's below the port, it's still perfectly useable.