Search found 17464 matches

by Harold_V
Sun Jan 19, 2020 5:16 pm
Forum: General Discussion
Topic: Internal tapered bore
Replies: 8
Views: 219

Re: Internal tapered bore

I strongly suspect the cartridge in question is not of that design, and may, indeed, be a rimfire type cartridge, which was common in those days. It would be of tapered design, but without a neck and shoulder. Such cartridges don't have headspace issues, as they orient on the rim, unlike shouldered ...
by Harold_V
Sun Jan 19, 2020 5:09 pm
Forum: Lathes
Topic: grinding carbide inserts
Replies: 10
Views: 266

Re: grinding carbide inserts

That solution may not be one when the tool is put to use in serious roughing. There's a tremendous amount of heat generated at the cut, which, in turn, heats the holder. That, of course, depends on the machine on which it's used. My Graziano, which isn't necessarily a robust machine (although adequa...
by Harold_V
Sun Jan 19, 2020 2:49 am
Forum: General Discussion
Topic: Internal tapered bore
Replies: 8
Views: 219

Re: Internal tapered bore

The idea of a reamer may be a better choice, as the typical cartridge length versus its diameter is likely to require a bar size that is too limber to work well. It would help if it was made of solid carbide if you have no alternative.

H
by Harold_V
Sun Jan 19, 2020 2:26 am
Forum: Milling Machines
Topic: installing quil on mill drill
Replies: 31
Views: 1895

Re: installing quil on mill drill

I feel you're doing just fine. Your logic is good, and the method by which you're trying to determine the condition of the shaft is good. However, there is another way you can pursue this, assuming there's a reasonable length of shaft. If you place the shaft in a V block, when you rotate it if it's ...
by Harold_V
Sat Jan 18, 2020 5:32 pm
Forum: Milling Machines
Topic: installing quil on mill drill
Replies: 31
Views: 1895

Re: installing quil on mill drill

Assuming you're placing the indicator at the extreme end of the part, I agree that the center is not concentric. If the part is ground, it may have been ground in a centerless grinder, so while it may (or may not) be straight, the center has no relationship to the grinding process. I worked in preci...
by Harold_V
Sat Jan 18, 2020 5:17 pm
Forum: Lathes
Topic: grinding carbide inserts
Replies: 10
Views: 266

Re: grinding carbide inserts

The bottom line on this subject is there is no rule that says you can't sharpen or refashion inserts. So long as you can do the alteration and get them mounted, and they serve your intended purpose, I see no problem, especially if you've made provisions for holding an altered insert. There's also no...
by Harold_V
Sat Jan 18, 2020 2:57 am
Forum: Build Log
Topic: "Catherine", a USA "Sweet Pea" engine build
Replies: 245
Views: 99482

Re: "Catherine", a USA "Sweet Pea" engine build

Instead of dimpling the hole locations, they had them marked with a cross-hair symbol. This made them easier to see, but I think that it made it more difficult to center-punch the holes. In one case the punch wandered a little bit and it was difficult to shift it back. Perhaps it is just my inexper...
by Harold_V
Sat Jan 18, 2020 2:52 am
Forum: General Discussion
Topic: Creating a GROOVE inside a very small TUBE (on the lathe)...
Replies: 9
Views: 277

Re: Creating a GROOVE inside a very small TUBE (on the lathe)...

As your post relates to lathe work, it would be best placed there, but it's not a requirement. It's fine where it is. Dave's advice is spot on. It's not all that hard to hand grind a proper tool, one you'd mount in your tool post. That will allow you full control over where the groove is located, an...
by Harold_V
Sat Jan 18, 2020 2:46 am
Forum: Lathes
Topic: grinding carbide inserts
Replies: 10
Views: 266

Re: grinding carbide inserts

A slow speed diamond wheel isn't necessary. I use a wet 220 grit diamond wheel and have been known to sharpen inserts, especially if I need a given geometry. In general, it's not a good idea, though, as you lose the very thing inserts provide--the ability to change a cutting edge and not lose regist...
by Harold_V
Fri Jan 17, 2020 2:42 am
Forum: Milling Machines
Topic: installing quil on mill drill
Replies: 31
Views: 1895

Re: installing quil on mill drill

It's not difficult to post pictures on the board. They can be hosted on the board, or elsewhere, with a link included in your post. However, considering the likelihood that the source can (and most likely will) go away, you are best served uploading them to the board. If you'd like to do that, it's ...
by Harold_V
Thu Jan 16, 2020 4:39 am
Forum: Live Steam
Topic: Silver Soldering Leaf Springs
Replies: 14
Views: 621

Re: Silver Soldering Leaf Springs

It should be obvious to all that heating any spring material is going to alter its ability to behave as a spring. It is generally just medium to high carbon steel, so it gets annealed by the heat required for silver solder to melt. Any quenching offers the risk of failure due to fracturing upon flex...
by Harold_V
Wed Jan 15, 2020 2:31 am
Forum: General Discussion
Topic: Keeping drilled holes aligned
Replies: 38
Views: 1025

Re: Keeping drilled holes aligned

In response to the ability to locate holes consistently, with precision, for the most part, hole locations were held to ±.005" on the electronic chassis that used to be made when the Sergeant Missile was in the development stage. All holes were drilled on drop spindle mills (think BP, although all o...