Well, Harry, here goes: #1--What materials were used in full sized practice and WHY cannot the same material be used in our models? I'm using ground Stainless in mine and if I have to replace it after several years, I can do that. #2--WHY must the inside of a pump bore be lapped instead of just a good bored or reamed finish? Isn't the rings/packing job to take up any small irregularities in the finish of the bore? Just the rambling thoughts of a total newbie. Al Messer --- Harry Wade <hww@xxxxxxxx> wrote: > There is always the "other" ME list where of > late the conversations > have centered around such compelling subjects as > manure, bovine and > chicken, among others. Fascinating reading. :-) > I've been quiet because > I've been busy handling life, juggling the care of > unwell and aging parents > with a full work schedule and deadlines. It's just > that time of life. > Workshop-wise I've been getting a little > done but what little I've > been able to do has been taking me closer toward the > material wall - that > point at which I can no longer make substantial > additional progress without > biting the bullet and buying some expensive > materials. At that point we > pause, . . take a couple of deep breaths, . . and > pull out the checkbook. > It's a good time to pause though because there are > some design and material > selection choices to be made, and best not made in > haste. > I have a couple of questions for the list > though, now that we are > at it, about axle water pumps. > #1 - I know that for some years Monel has > been recommended or > specified as the ram material because it is less > susceptible to galling > than stainless and I wondered if anyone is or has > used it and what your > results were. I can't seem to find it in a ground > finish at any price (see > checkbook above) so would turn and grind my own from > oversize stock. > #2 - I have bored (not reamed) my pump body > (.500" diam x 2.5") and > would like to put a lapped finish to it. I have a > 1/2" split brass lap but > I can't afford to buy a series of lapping compunds > at $$ per grit. Any > suggestions as to how to proceed? It may very well > be that for a one-off I > would come off better sending this out to a > commercial lapper. > > > Regards, > Harry Wade > Nashville Tennessee > > MODEL ENGINEERING DISCUSSION LIST. > > To UNSUBSCRIBE from this list, send a blank email > to, > modeleng-request@xxxxxxxxxxxxx with the word > "unsubscribe" in the subject line. > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.