NEMES Monthly Meeting

February 2008

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!

DSC03304.jpg (121430 bytes) That is Cody talking about his work.    Video of the meeting start and Cody's talk.

DSC03299.jpg (104911 bytes)  DSC03300.jpg (87089 bytes)  DSC03301.jpg (74062 bytes)  DSC03302.jpg (195449 bytes)  DSC03303.jpg (112075 bytes) 

Photos of the usual suspects

 DSC03305.jpg (78052 bytes)  Alan Bugbee spoke about the refrigerator magnets he bought to entertain his grandkids.  

DSC03306.jpg (94100 bytes)  Dick Boucher and Frank Dorion (R) Frank talks about his quest for a binocular microscope.

  DSC03308.jpg (95172 bytes)  DSC03307.jpg (69925 bytes)  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.  

DSC03355.jpg (58070 bytes)  DSC03357.jpg (105053 bytes)  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.

DSC03356.jpg (146835 bytes)  Laps don't have to be pretty to be effective.

DSC03358.jpg (123597 bytes)  These laps are very simple.  A cut in the stock then use a small wedge tapped into the end of the lap.

DSC03360.jpg (105784 bytes)  DSC03362.jpg (79157 bytes)  DSC03363.jpg (73724 bytes)  DSC03364.jpg (83897 bytes)

(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

DSC03365.jpg (83219 bytes)   DSC03366.jpg (80691 bytes)  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. 

DSC03367.jpg (84074 bytes)  

DSC03368.jpg (129845 bytes)  DSC03369.jpg (139884 bytes)  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.


Return to NEMES homepage