Cleaning Up Scored Cylinder???

[Patrick1903]

Why would one sand transfer off when acid removes it without sanding?

Why would one use acid when they could sand off transfer?

 

[Bob Hedgecutter]

Why would one use acid when they could sand off transfer?

Why would one run a saw long enough and lean enough for transfer to occur?

You are heading down a chicken and egg tunnel- just agree that if there is transfer and it can be cleaned off- clean it all off by WHICHEVER means suit you before reusing that cylinder.

 

[bwalker]

Why would one use acid when they could sand off transfer?

Because it's easier on the plating. Remember nicisil is silicone carbide particles bonded by a nickel substrate. Nickle is pretty soft.

 

[Patrick1903]

Why would one run a saw long enough and lean enough for transfer to occur?

You are heading down a chicken and egg tunnel- just agree that if there is transfer and it can be cleaned off- clean it all off by WHICHEVER means suit you before reusing that cylinder.

It seems like many people really like to use acid, others have had some bad experiences and no longer use it, and others have never tried because it’s harder to work with and/or they don’t have it in their shop, garage, etc. Mostly just asking the counter to the previous question that was asked. Always interesting to hear/see peoples experiences.

 

[Patrick1903]

Because it's easier on the plating. Remember nicisil is silicone carbide particles bonded by a nickel substrate. Nickle is pretty soft.

Gotcha. I have seen/heard that it’s hard to damage the plating by sanding. I suppose that’s what most people who sand it away hang their hat on.

 

[bwalker]

Gotcha. I have seen/heard that it’s hard to damage the plating by sanding. I suppose that’s what most people who sand it away hang their hat on.

Sanding is easier, that's why most guys use that method.

 

[Mad Professor]

Sanding is easier, that's why most guys use tgat method.

I see results from impatient sanders who use 50-80-120 grits and their crosshatch are almost as bad as scores.

 

[djg james]

I usually split a dowel rod on one end and chuck in my drill. I then put scotchbrite in the split dowel and use the drill to polish the bore. Spray a little pb nutblaster on the scotchbrite and let it rip. Lot safer than the acid and will leave the bore polished shiny. Then replace the scotchbright with a piece of 360 grit emory cloth and hit the cyl again, just enough to leave a nice cross hatch pattern.

I've got a cylinder that will need the same, why the cross-hatched pattern? Don't you want the inside completely smooth?

 

[bwalker]

I see results from impatient sanders who use 50-80-120 grits and their crosshatch are almost as bad as scores.

At face value it seems to me that sanding would remove more than just the aluminum transfer. Do I know this for sure? NOPE. And I am not chomping at the bit to find out. It just seems to me like a hack way to go about it.

 

[bwalker]

I've got a cylinder that will need the same, why the cross-hatched pattern? Don't you want the inside completely smooth?

A proper cross hatch pattern aides in seating rings.
I will do this very lightly with a ball type hone and a light spray oil like Kroil or PB blaster. I have been doing this for years with all sorts of Nikisil cylinders from 50-500cc+.

 

[cookies]

Acid is far less physical effort and you only need a couple table spoons of the hardware store diluted version of muriatic acid, a small hand full of Q tips, bucket of water for dunking the cylinder in, a small wire brush, gloves and eye glasses. Some guys like flapper wheels or ribbon sand paper on their rotary grinder because it is very fast and others like using abrasives by hand.
I prefer starting with acid because it will show cylinder scoring that does and does not go all the way through the plating. I like the fact it removes the aluminum without using abrasives and exposes holes in the plating. On a rare cylinder with high likeliness of liner damage I would likely use abrasives instead. I do not like being tied to one method for anything involving repairs, there are just too many variables in the real world.

 

[bwalker]

Acid is far less physical effort and you only need a couple table spoons of the hardware store diluted version of muriatic acid, a small hand full of Q tips, bucket of water for dunking the cylinder in, a small wire brush, gloves and eye glasses. Some guys like flapper wheels or ribbon sand paper on their rotary grinder because it is very fast and others like using abrasives by hand.
I prefer starting with acid because it will show cylinder scoring that does and does not go all the way through the plating. I like the fact it removes the aluminum without using abrasives and exposes holes in the plating. On a rare cylinder with high likeliness of liner damage I would likely use abrasives instead. I do not like being tied to one method for anything involving repairs, there are just too many variables in the real world.

Curious why you would use abrasives on a rare cylinder?

 

[DennisCA]

I guess perhaps if you use acid on a cylinder with liner damager, it will eat the aluminum under the liner making the repair job impossible or at least very difficult?

 

[cookies]

Curious why you would use abrasives on a rare cylinder?

Because acid could potentially get under the plating undermining it where it is thin or worn through.

 

[bwalker]

Because acid could potentially get under the plating undermining it where it is thin or worn through.

Makes sense.

 

[DennisCA]

What happens next? I mean, you sanded it off and find the lining is damaged, what then? Can it be ignored if it's small enough, or is it replating time?

 

[bwalker]

What happens next? I mean, you sanded it off and find the lining is damaged, what then? Can it be ignored if it's small enough, or is it replating time?

IMO, no. Sooner rather than latter you will break a piston skirt with a worn cylinder like that.
I believe one of the plating companies will replate saw cylinders.

 

[Mad Professor]

Because acid could potentially get under the plating undermining it where it is thin or worn through.

Just where there is holes/scores through the plating will acid eat underlying aluminum. IMHO if cyl is that bad it won't go on one of my saws or one I'd sell.

You can put grease on any obvious/suspected defects prior to treating with acid. The acid will not get under the grease, same for port edges.

 

[seagiant]

Hi,
Well, got the Saw back together.

Started it up and it ran for about 10 sec. and shut down and would not start.

Took a compression reading and it was 150.

Noticed a scrapping noise while pulling starter.

Took the Cylinder back off to see if it was the piston or cylinder, both good.

Sound is coming from inside the engine while crankshaft rotates???

I guess a bearing check is next...

Well I will know how to completely strip down an ECHO anyway!

 

[Aknutter]

Possible circlip came undone...hmm?