apt subject line terry. At an hour a cylinder, boring sound boring.
glad everyone's vouching your good work, chat to ya later in the week.
Emailed this to ya, but maybe ya learned mates might want to see my new ally tank and seat.
all the best, al
G'Day Mate, hey that looks great! Has it arrived yet? Cheers, Terry.
How much is a "stuffed up"?
An answer in mm is fine.
Is that 0.005 on the bore diameter, depth of cut, or feed per revolution.
What kind of boring tools do you use? On the machines I designed we would use carbide insert boring bars, one for rough, one for finish. Each had an insert designed specifically for the task and Material. Much more then O.005 inches.
Old Machinist taught me bore for straightness, ream for size, hone for finish.
With modern tooling the second and third steps are generally not needed. Although we set up the boneheads in Milwaukee with a hone to finish their connecting rods.
G'Day Mark, I'm not sure if you were asking me or Morini the "stuffed up" question, but if it was directed at me, my first attempt to bore my 70mm Suzuki GS1000 cylinders to 72mm ended up with a sloppy .004" clearance on #1 cylinder.
I know that "a poor tradesman blames his tools", but the "depth of cut" micrometer that came with my boring bar looks like it was used at one time as a hammer, so if you have a good one there that you'd like to sell, or know where I can buy one, please let me know, at the moment I'm using my digital vernier which appears to be very accurate, but a bit tricky, as it doesn't "hold" the tool like the OEM mike does.
.004" is still within spec, but I couldn't bring myself to use them, but recently I scored a set of "almost new" 73mm (1085cc) MTC forged pistons, so when I get time I'll bore the cylinders out to suit them, although I'll stop a few thou short and use my recently aquired Ammco 500 micrometer adjustable 4 stone hone to finish them.
The .005 is depth of cut. The tools are, I believe, carbide inserts sweated onto the tool holder, they hold their edge really well which is good, as I tried to resharpen an old one with a chip taken out of it on my bench grinder, and it was damn near impossible.
I've never tried to ream out a cylinder, but it makes good sense, and I guess in a way the Ammco 4 stone hone is about as close as the average bike shop would get to a reamer anyway? It's a pity it's too big for this engine, I ran it for a couple of passes in the GS1000 cylinder, and was very impressed with the smooth, even finish.
The Ammco hone was in fantastic condition (thank you EBay!) and came in the original steel case with all the accessories, and even had all the original literature, including an advert for a conrod finishing honing machine, which I thought would be a pretty cool old tool, if I can find one?
Oh, and Frank, the 1200 conversion kit for the 883 is so cheap I don't know why you'd bother, but my 17" swing lathe with it's 1 metre bed would likely handle the "roughing" cut's, I've bored a couple of CB750 sleeves in the 3 jaw chuck, then (after shrinking them back into the cylinder block) finished them on the boring bar, which seemed to work quite well. But to be honest, I'd rather start with a 1200 Sporty and buy the 1400 kit anyway............
Cheers, Terry.