NEMES Monthly Meeting
Photos and video by Errol Groff
Our speaker scheduled for this evening was our own Rollie Gaucher. Rollie is a craftsman of wide renown, his Bentley rotary aircraft engine is as fine an example of the model makers art that you will find.
Our meetings usually start off with brief announcements followed by "show and tell" time. This month one of our guests was Cody Robinson, a student at H.H. Ellis Technical High School in Danielson, CT. Cody had come with me (Errol Groff, his shop instructor) to the meeting. I had him bring along some of his blacksmithing work which he has recently been working on. He didn't know I was going to volunteer him to "show and tell" but he handled the situation with grace.
This is the first attempt at video of this length and there is a lot of learning yet to be done. Please have patience!
That is Cody talking about his work. Video of the meeting start and Cody's talk.
Photos of the usual suspects
Alan Bugbee spoke about the refrigerator magnets he bought to entertain his grandkids.
Dick Boucher and Frank Dorion (R) Frank talks about his quest for a binocular microscope.
Rollie Gaucher started his talk with some information about the forging and machining of two frames for the F-22 fighter plane. He followed with an information filled talk on the finer points of lapping in the home machine shop.
F-22 Segment Rollie's Lapping Talk Part 1 Rollie's Lapping Talk Part 2
These are big files, that is the nature of video clips. The quality is not so great as there is not so great lighting in the meeting hall. Fine for most purposes but not for a video camera, my camera is supposedly good in low light but there has to be more than we have in the hall. You will hear some squeaking in the audio on some tracks, that is the low rent tripod head squeaking as it gets moved. Well, this was a first time out at recording meetings and I hope that things will improve. Still, if you weren't there it is better than nothing.
For more information about lapping go HERE
17 February 2008
I took a ride up to Rollie's shop today and took photos of the laps he was using during his talk at the February meeting.
This rather massive lap uses a taper insert. There is a shoulder in the bore of the lap and the tapered part of the screw bears on the shoulder spreading the lap to adjust for size. The slits were made by first drilling cross holes through the lap. Then, breaking a bandsaw blade and feeding it through one of the holes, re-welding the blade, cutting the slot. Break the blade, feed through the next hole and repeat as necessary.
Laps don't have to be pretty to be effective.
These laps are very simple. A cut in the stock then use a small wedge tapped into the end of the lap.
(L) The retaining ring and the lap inserts.
(C) Retaining ring placed on the crankshaft with one insert in place.
(R and R) Retaining ring and both inserts in place on the crankshaft. The arrow points to the set screw which a. captures the inserts and prevents them from spinning in the retaining ring and b. provides a means of adjusting the laps for sizing the journal
On these laps the slits were made with a slitting saw on the mill Arrows point to the adjusting screws. You would want to use a fine thread screw to obtain a better level of adjustment.
A variety of insert laps. The retaining ring has a set screw which allows for adjustment of the lap. The ring is hand held and allows the operator to "feel" the cutting action of the lapping compound.
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