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Scnell Gelb, thanks for the video connection. I watched it a few times and then read through the comments made by people and thought about some things that were left out of the video. The presentation of the video could have been better. I have numbered a few points that could be made to improve or explain to the layman about the process used. While looking at some of the tooling it was evident to me a lot of time and thought had gone into this idea. A person who isn't a machinist cannot visualize how these pieces are used. It was plain to me the first time i saw it but then again after 45 years of machining i know a thing or two and certainly understand how it looks "rough and ready" I'm not here to defend the company providing that service but merely making an attempt to explain to the "Layman/Person in the street" why some things look odd or out of place.
I try to present my views to the Non Machinist people so as not to over complicate the description.
If i was to explain all this in Machinist's language it would boggle people's mind. How may people understand these terms that we use on a daily basis: T.I.R. Eccentricity, Ovality, Chatter, Transition Fit, Interference Fit, Clearance Fit, Tolerance, Spfm, Feed/Rev. Parallelism, Top Rake Angle,and Side Rake Angle, Front Clearance, Side Clearance, Rigidity, Overhang and even more that i won't go into. ALL of these terms are applicable to the video.
1 The video showed the tooling in a box and chips all over the bearings and cutter.
The bearings are sealed brgs. so no debris can get in them.
2 Cutting chips/swarf all over the tooling.
This was probably taken AFTER the work had been done.
3 Method of alignment of jig to original bore was not shown.
In the box was a large turned slug which would fit into the bore of the alignment jig and also into the bore in the engine case for precise alignment and then the jig would be locked down in place.
4 The arbor used to mount the cutter on is heavy duty and the locking bolt at the cutter end is the correct type used with arbors.
5 The narration could have explained more about the process to set peoples mind at rest.
The cutter used is a modified Face Mill made from HSS (High Speed Steel)and has a lead ground on the front to reduce chatter. The cutter will give a good finish but over time will dull but it is easily replaced after a regrind. Normally two cutters would be used., a roughing cutter then a finish one but maybe they didn't show that part or didn't feel a finish cutter was needed.
6 The removal of the snap ring using a screwdriver and a pry bar.
Should have been done with the correct snap ring pliers and not with a screwdriver and a pry bar.
7 No explanation of how they were going to "fill in the gap" between the case and the flange.
The replacement flange has to be made to fit the bore with the same tolerance as factory. Some people were suggesting JB Weld being used to fill the gap.
My method of machining the bore would use a Right Angle Head with a variable speed drive and a Boring and Facing Head to mount a boring bar in. This setup is then permanently fixed onto a precision tool slide with 7" of travel that can feed the tool into the bore. All of these parts are then attached to a custom made angle bracket which will span the full height and width of the engine where it mates against the gearbox.
This is all rather long winded but at least explain some of the different ways to achieve the same results.
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