Where do we go from here
Where do we go from here: As most of you folks know, much of the Machine shop work is very repetitive from day to day. I’ve been thinking about what kind of page arraignment that would retain your interest. I’ve decided to continue taking snapshots as I go through my daily work and see what you folks think about this kind of layout. Please send your suggestions.
Boring & Honing, Straight & Round: If the Cylinder boring bar isn't adjusted smooth and close the final bore may not turn out round. Most every operator agrees that when possible, the cylinder should be mounted upside down when tightened in the fixture. When the tool bit hits some of the porting the bar may Jump slightly and cause an interrupted cut. An inaccurate bore from an interrupted cut is almost impossible to straighten out with a cylinder hone.
A tip for Hone stone storage: I always remove and replace the hone stones in the same location, Every Time.
A simple storage rack can be made out of a 2x6 board.
It’s a good practice to check the bar for “Run Out” & “Flex” every few month’s.
If your machine makes a “Familiar Chatter” sound, your bar may be out of adjustment or the Tool Cutting angle may be incorrect.
Any Machine Shop which works on small engine cylinders MUST have a set of Expanding mandrels. In the Old Days, K.O. Lee brand was the only name in town. Fast forward 25 years & high quality import brands are available for more economical prices.
I’m finishing up the 390 Husky cylinder next week. In this illustration we didn’t have a large enough mandrel to mount up this cylinder. Instead, a 3 jaw chuck at the base and a live pipe center at the top enables us to FUDGE a mounting for a light counter bore.
In case your wondering what ever happened to the V-6 Mercury block, I GAVE UP.
The crack in the cylinder ended up too close to the Exhaust & Transfer ports. Since there is so much money involved in this project, we decided not to continue. If it were a simple single cylinder engine, we may have finished it up.
Back to the 390cc Husky Cylinder.
The top & bottom are cut to size. Double checking the new sleeve in the head pocket. You can see how profound the acid etch port markings are. There's no excuse for missing port alignment.
Since all of our port machining is done by hand, A simple J-Head vertical mill works just fine.
On a good day, all of the ports can be cut and polished smooth in around 45 minutes. This kind of work is very time consuming. I’m pretty sure that most of us do this kind of work because we love the process, not because of it’s high profitability
One of the next projects is installing DH Boost porting in a Mac Kart engine. Dale Herbrandson is in his 70's now. The DH Reed valves were the beginning of Reed Valves on Motorcycles. I'd like to keep some of the history alive.
I put the reeds on this 440cc twin back in the Middle 70's. Dale helped me start my business, I'm forever grateful to know him.
Ran out of picture space again.
Next Week
"Old Dog"
JT