Hi all,

For some of the dimensions where I don't have proper taps, I've long kept a set of screws/bolts with a notch cut through the threads to clean out grimy and mildly damaged threads.
Considering the entirely marginal cost, they've worked OK.
But I'm thinking of buying some proper taps. Steel-on-steel cleanup performance kinda sucks.

Current considerations:

-derailer hanger thread, M10x1.0
-Square taper crank bolt, M8x1.0

I'm figuring these to be so close to normal that cost-per-use doesn't get prohibitive even for my mainly own-use purpose.

Wasn't planning on going for BB shell taps, but maybe a set of pedal taps.

I'd be glad to take recommendations on other taps as well as where to get them (a pre-Ebay search question...)

Cheers,

Maybe an M8x1.0mm die for nutted bottom bracket spindles. I assume you already have the standard M5x0.8 mm, M6x1.0 mm, etc. taps.

Park Tool sells a tap for the derailleur hanger thread and others, have a look. I don't how well they are priced or quality but Park is typically good stuff.

Have you had trouble with the threads inside of square tapers? I don't think I've EVER seen one of those threads messed up...?

McMaster Carr is a good source for quality taps in nearly every size. There's nothing "bike specific" about most metric taps. If cost is a concern, Enco, Travers, and many other tool suppliers are probably less expensive than the Park brand, and you can select from high speed steel, cobalt, and coated versions, along with a variety of grinds, including "bottoming" taps, and even a selection of thread engagement levels.

Take a look at "www.use-enco.com".

Yep. I have pedal taps and a derailleur hanger tap. None see much use but they are there when I need them. Can't recall where I bought them but I didn't pay much. I'm just cleaning up existing threads, not cutting new ones. If I ever had a square taper bottom bracket with mangled threads, I'd probably just replace it.

You'll have a more difficult time finding an (inexpensive) small tap handle that is centered, not the taps. Even Hanson (Irwin branded) taps are fine for occasional use, barring exotic materials such as case-hardened steel. If you can find an older General tap handle, they're good quality...the new ones are iffy, sometimes concentric, sometimes not.

In the US, Triumph makes very good taps, though finding a distributor for the metric ones can be difficult. I would personally plan to have at least an M5x0.8 (which needs a small handle), M6x1.0, and an M10x1.0 (which both need a larger handle). Between those three sizes, you'll cover 90% of threading issues on a bike. Bottom bracket/pedal taps are more or less specific to the bicycle industry, due to the reverse threading on opposite sides (so, Var, Unior, Park, are pretty much the only companies selling them).

Remember to liberally oil the taps before use, or periodically during heavy use.

I can count on one hand the number of times a die has come in handy in a shop environment, as most male threaded parts are usually toasted by the time I see them. For personal use, I can see their appeal.

I wouldn't bother with either an 8 x 1 tap or die. BB spindles are hardened steel, and you'll just ruin your tap or die on them.

Well, yeah.

A relative of mine asked if I could put together a beater bike for him, so I pulled a frameset from the boneyard. It was missing one crank bolt.

"Can't let it go like that" I thought, and tried to insert one. Stopped rapidly, took too much force. Brought out one of my notched "cleaner" bolts. It too took a lot of force, and not much came out. But it flattened the thread profile on the "cleaner" bolt.

If it comes down to the same money, I'd rather buy a tap than another BB. Get this beater bike on its merry way.

For a really good full set of metric taps, find an older Craftsman set on eBay. With Amercan made taps. These are far superior to any of the Hanson taps, (that are rebranded by many companies, and are now made in China) and the whole used set won't cost much. New Craftsman taps, (along with many other products of their's), are now all Chicom garbage. If you break one of the older Craftsman taps, replace it with a Greenlee from McMaster Carr.

I have derailleur hanger and pedal taps. Both have been useful multiple times. I've never encountered a need for another tap.

The ones I have are for RD hanger, cage and eyelet threads, and drop out adjuster screws.

One of the better sources for taps and dies with both high quality and diversity of sizes is Victor Machinery - Metalworking tools and supplies. Unlike the Park tool
pedal taps which are carbon steel (more brittle and easily broken than high speed steel) they sell what amount to pedal taps in
HSS for ~$40 for both (R = $15, L = $25). They also have dies for these as well. For those concerned the vast majority of
Victornets taps are US sourced. For really odd ball threads, they will have taps. As noted by others, bike metric threads are
all standard, however the English threadings are all 'non-standard' eg French RD hanger thread 10mmx 26TPI.

Granted, for cleanup of threads carbon steel is fine and 9/16 taps are really hard to break, never the less, HSS taps normally
sell for 30-50% more than carbon steel for the same size and carbon steel taps are meant for clean up only. Craftsman tap/die
sets were almost always carbon steel.

I find I use an M5 x 0.8 on occasion to clean up water bottle bosses and some braze on barrel adjusters are that size.

The tap will snap since they are made of a hard brittle steel. Even if it doesn't the hardened spindle will quickly dull them. That's probably why your bolt would work better for these situations. Square taper BB spindles are pretty cheap and even the cartridge BBs are only 20$ and last a heck of a long time. Our local co-op has a tap and die set but they don't bother tapping spindles or cutting the threads on the ends of nutted ones.

I'd buy a couple of m5 x 0.8 maybe a bottoming one too.

buy a good sized tin of cutting oil . as well .. use generously.

thread cutting is very much, 1 tiny step forward, 2 steps (clear the chips) back.


Pedal taps are quite exclusive to the bike Biz .. Rh & Lh thread pair. 9/16 x 20.

>sch: I really don't know the composition of the older Craftsman taps I recommended, but I've used them for 20+ years for auto related fabrication work, (cutting new threads), and I've never broken one. Whatever metallurgy they used, they are very durable. New Craftsman stuff is different; and MUCH lower quality. Other than these, I use Snap-on taps, and I've broken plenty of those.

They are NOT bike specific at all though.

Everyone seems to be assuming that the Park taps are heavily marked up. However I just checked and all their taps are <$12 each on Amazon. Meanwhile McMaster has an M10x1.0mm General Purpose tap for $20, and of course it's up to you to make sure you get the right size, thread pitch, and style. So Park is not a bad deal in this case. Maybe the more expensive ones will last longer or cut better threads in a new hole (or maybe not), but most users are probably just chasing existing threads anyway. And it's guaranteed that you didn't accidentally order the wrong thread pitch (or whatever), because they don't sell anything with the wrong thread pitch.

That is interesting, just did an Amazon search myself and lowest price for Park pedal tap set I see is $44. (??) Victornet has HSS 10x1 for $6.20
My Craftsmen sets, metric and English, date from the early '70s and are carbon steel and still work fine. Had to get my 10x1 from SnapON
in that time frame though (US made HSS) for well under $10, needed it to tap out the hanger on my PX10 for a Suntour RD.