I've tried not to be long winded here just wanted to describe what was
going on before I asked the next best remedy, any and all suggestions
will be gladly accepted.thanks for bearing with this.
I am interested in adding some new business to my shop doing small
engine cylinder boring and honeing as there are a lot of cycle and lawn
shops waiting up to two weeks to have them done since the local machine
shop only does small cylinders when they have enough to fill a days
worth of work. I am familiar with the engine related aspects of
clearances and measuring. I don't have experience machining cast iron
liners though and know not to bother with nikasil ones. I have an enco
13" gap bed lathe and enco mill with 5" quill plunge with r8 shank
10x54 on the table. Chatter marks and varying spirals are what I get
with either machine. I have used an offset boring head in the mill with
both brazed carbides and hss tool inserted and locked through type bar.
On the lathe I have bolted to faceplate and bored with hss through bar
type boring bar with about the same results.
Even taking a light cut at 1 thou on the radius per cut still had light
patterns requiring about 6 thou on the diameter worh of honing to make
marks realy dissapear.
Both of these though are with bars atleast 5 inches long on the junk
cylinder I was test cutting and only supported on the tool holding end.
I am guessing this springing is what is giving the patterns?
It was suggested I use the lathe and make a bar supported at both ends
with the cutter passing through the cylinder mounted to the crossslide.
This seemed like a better idea being supported at both ends, but would
need to be about 18 to 24" long since it would need to be twice the
overall height/length of the workpiece for the cutter to pass through.
Had thought of using an angle plate with a hole bored through the center
would make it easy to hold the work and easy to get perpindicular to
the ways and only slightly difficult to center them once the faceplate
Would this give me enough support using say a 1.25 bar since some of the
cylinders I would do are as small as 1.5 in maybe less?
Is overall machine rigidiy a problem ? I have been told the asain
machines and r8 shank just arent sturdy enough. True?
I have also had my eye out for a 16 " southbend since another job I have
been doing tapers on would go much nicer on it... if the supported
boring bar is a better option just needing a sturdier tool.
Or should I just come off the change and get a van norman or kwik way
bar and be done with it? This also becomes a prob b/c van norman 944
doesn't go small enough, kwik way bars look like I would need both a
fws2 and an fr model to cover the range I guess to see.
18 years ago