Crappy-o-La

[graham-xrf]

My word for lesser quality items.
Sure, it was a piece of one of those carbon steel tap and die "sets" you can pick up in DIY stores, or even shopping at ASDA, but it did not have to do much! A basin tap fitting thread anchor. Access was too limited for the over-long zinc-flashed M8 stud, so I decided to re-purpose a Allen head M8 bolt by extending it's threads a cm or so (that's about a half-inch), and cutting it off. Given where it was being used, the donor M8 was to be from Britain's finest stainless. Truthfully, it might have been China finest - I don't really know.

Any-Hoo, the business of die-cutting M8 A2 stainless was always going to be a bit fraught. WD40, the only handy cutting oil. The bolt probably had it's threads rolled on. Whatever.. it was damn tough stuff! Even so, I went slow, 10° or 20° at a time with lots of chips clearing and squirts of WD, and getting a work-out on it.
The hand bars are coarse threaded, and a sloppy fit, and too thin for working up heat on a M8. Still - slowly getting there. The thin bars hurt, so I shoved some small hosepipe over them. Why is it that the dimple-anchor screw has to be re-tightened every minute or so?



So..
The thin bars bend at the root. The housing lets go in a failure mode that can leave one with skinned knuckles, but lucky I had the nitrile gloves. Trying to encourage even a final half-turn and a threads clean-up fractured the other bar collar as well. There did follow, some Anglo-Saxon expressions of a robust and unseemly nature!

Fortunately, I had another "set". ToolZone from the Aldi store center aisle. This set was dedicated to dies in inches, but the die holder is marked 25mm and also 1". The die did "fit", as well as these things ever do.

I know HSS steel is better, and Cobalt is best, but I long for a classier, stronger, more comfortable holder with handles that don't bend at the root before breaking the die!

 

[Nogoingback]

When I needed a die stock, I bought a good quality NOS Greenfield on eBay. Excellent quality, perfect condition,
and cost 12 dollars. All the new stuff looked like junk.

 

[Winegrower]

It's easy enough to make a good die holder, no?

 

[benmychree]

Stainless steel and carbon steel cutting tools are not liable to give satisfaction, to begin with, and a pieced up die stock certainly does not help matters. The choice of WD40 was only slightly better than no lubrication at all, a good oil intended for tapping would have perhaps made a difference.

 

[graham-xrf]

It's easy enough to make a good die holder, no?

The choice goes - "Please fix the bathroom - urgently"!
Find die holder. Find 8mm bolts. Get going on it with new mixer tap set.
Or .. make a nice die holder somehow. Then fix the bathroom.

Interesting though. It set me a-thinkin' how one would make a die holder. Lathe work only.

Stainless steel and carbon steel cutting tools are not liable to give satisfaction, to begin with, and a pieced up die stock certainly does not help matters. The choice of WD40 was only slightly better than no lubrication at all, a good oil intended for tapping would have perhaps made a difference.

You are right. Unfortunately, getting in all the best stuff needed PDQ was not really an option. I had to go with what I had, and I am in the country, shielding from the pestilence anyway. Probably A2 stainless bolt that has been cold worked rolled was going to be a b**** whatever substance the tool was made from.

You do raise a good point about tapping oil and WD40. I think I recall reading WD40 being good for aluminium, but in general, I have to learn what exactly is "tapping oil" anyway, and how does it work? I am sure there is a whole wisdom about which substances suit which metals and tasks. To take an extreme example , a very high pressure breakdown oil like (say) Hypoid EP90 used for car transmissions would likely be a bad choice, (and smelly too)!

Up to now, I have relied on that the plastic bottle says "tapping oil" on the label, but I didn't have any. Everything at my place is in a state of flux - especially the hobby machine stuff. Some oil OK for tapping may be somewhere among the stored stuff. That's OK. With bathroom fixed, attention moves, and I see the cleared land for the outhouse, and the decision is "should it be 16 x 10? Can I push it to 16 x 12? Hmm.. and I start visualizing when I set up the South Bend in there. Bathroom plumbing, junk die holders, tapping oils, etc. is, to be honest, necessary stuff, but nothing I would enjoy.

 

[benmychree]

I have no idea what is available in Britain, but here in the former colonies we have Rapid Tap, TapFree, and TapMagic, to name a few, the latter is my favorite, and it does not smell bad.

 

[graham-xrf]

Not in the shops. Other generic stuff is, of course, available.
Resorting to (UK) eBAy and (UK) Amazon yields 4 oz can of Winbro Tapfree. That's just the can - no oil!
Another is TapFree and AlumTap. 2 cans. Just the cans. No oil. collector's items I suppose.
Amazon yields only 500ml of something called CT-90.

From what I do know of it, one needs something that will break down at the pressure under the cutting edge. Vegetable oils, lard, animal oils, light oils with added surfactants, apparently all do well. A straight hydrocarbon solvent (not allowed anymore), trichlorentylene, it seems is very good when turning, with no good explanation as to why. By now, I would have thought that the mechanism of cutting "oils" in assisting the process, and improving the finish is more known, and not just the recipes of proprietary concoctions.

I know there are homebrew recipes all over the place, and every kind of substance that legions of old timers would swear by. Not that they are needed. Cutting oil is cheap enough. What I find odd is how so little is known - tested fact - unrelated to attempts to market anything. This is one area where genuine rendered snake-oil might actually turn out to be very good!

 

[benmychree]

When I was an apprentice back in the mid 1960s, we used triclor mixed in with cutting oil and sometimes white lead for such purposes, then along came RapidTap, which contained (at that time) triclor, but worked much better than our homemade product. The government banned triclor and then a substitute was offered, which did not work very well, since then these tapping fluids have been improved and work well. I have been able to buy some of the original RapidTap on E Bay, and I do not think it works any better than the newer products. Before we had triclor, they used to use carbon tetrachloride, much more dangerous than triclor.

 

[ericc]

Even the US made tap and die sets at the big box stores seem to be poor quality these days. I have found that almost anything that one buys at garage or estate sales are much better quality. When those run out, there's going to be trouble.

 

[Bi11Hudson]

"Trichloroethane 1,1,1 Tech" vs "Trichloroethelene" The "~ethane" is the one outlawed, several years ago, "~ethelene" last I looked was still being used by gunsmiths. "Last I looked" being the key phrase there I have a small supply of trichloro~ in my shop. I don't use it often and I'm aware of the hazards dangers of using it. And there are several. . . But, except for Mommy EPA, there are some effects that no other solvent has. Except maybe carbon tet, which has also been outlawed.

Iron and its' derivitives, including steels, are porous at the microscopic level. Trichloro has a low enough surface tension(?) to penetrate that microscopic porosity. For use prior to painting, for example, it removes any moisture content from the iron. Yet will not attack a cured varnish on electrical equipment. Paint, on the other hand . . .

It was included in "Tap Magic" at one time for its' ability to penetrate the steel. As well as many other tapping fluids. Tap Magic was my preference. It also worked on brasses and bronzes. Though not as noticeable results as iron, they also are porous. However, it was not to be used on aluminium under any circumstances. Trichloro attacks aluminium turning it into dust. As does any chloronated solvent, for that matter.

I still use the "reformulated" Tap Magic, mostly out of "brand loyalty". And still mix in a little trichloro when what I'm doing is critical. I cannot recommend a replacement though. Because there isn't one. Thanks, Mommy, for making things harder.

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