thread chaser taps, which ones to get

I probably would not use em to death but I'd want them to adequately do their job in properly cleaning the threads when I do use em. HF has a set but I am hesitant. What set would you recommend? thank you for your time

I have the craftsman set, it does NF, NC and Metric...

head/main bolt holes would be my main interest. If they are sold seperately maybe I could splurge on some real good ones

Get a bottoming tap for each size and thread pitch,
www.travers.com
www.MSCdirect.com
www.mcmaster.com

Same here, very happy with them. Made in the USA. They don't really cut, they clean and re-shape. So you don't lose metal. I wouldn't trust HF for these. If the sizes are off, or if they shatter in the hole, like most HF stuff is garbage, you just messed up your block.

I have a couple sets of HF tap and die sets. They work fine. I don't use them real often but they are real handy when I need them. If you were going to make your living with them or want to hand them down to your grandchildren, then it would be best to spend the coin and get some more expensive ones. But for the occasional job, they have been well worth it for me.

Agreed. I have used my HF ones often and never a problem.

roll/form taps work well for chasing threads as well, because they "form" or "roll" the threads instead of removing material as regular taps.
something to consider if you only want to buy a couple.
they also come in coarse, fine, and metric.

"Whenever you’re faced with dirty or slightly burred female threads (cylinder head threaded holes in a block, spark plug holes in a head, etc.), you may be tempted to grab an appropriate size cutting tap to clean up the threads. The correct choice is to use a “chaser” tap. A cutting tap is designed to create new threads, whereas a chaser tap is designed to clean, re-form and restore existing threads."

https://www.summitracing.com/parts/...Q7eHL5AIVuSCtBh28YwNjEAQYASABEgKgTPD_BwE

Exactly. That is what you want to use to clean every thread before assembly. And to find out if there is a problem. Taps are to cut threads and I don't want to remove material unless the thread needs repair. But you still will want a complete tap and die set and bottoming taps for other thread repairs. Even a HF set will work and last the rest of your life.

(OK, I'll admit I have a tool fetish. But when I need something, I have it.)

I usually use a tap first time to make sure the holes are tapped to the bottom. When I know the holes are fully tapped, I'll use the thread chasers next time I have to clean out the threads.

Of course, using the right style of tap for the particular job is the best thing to do........technically.

In reality, for most of us that will use the tap one time on a set of threads to clean them up or to make a set of threads, any tap will be better than nothing.

I bought ARP thread chaser taps, a set of 5 course-thread in typical sizes for prepping a block. Don't recall what the cost was, or if I could have sourced the equivalent taps cheaper from a tool supplier like MSC or McMaster-Carr.

Summit sells ARP thread chaser sets and individuals. You may be able to find cheaper on Amazon or elsewhere.

https://www.summitracing.com/search...haser%20&sw=ARP%20Thread%20Chaser%20

I have a set of the cheap Summit ones and have used them effectively. If you are really cheap or just in a fix then just cut a vertical slot or two in the threads of a bolt and use that, you'll get the same result. For the price of the Summit ones, it's probably cheaper just to buy them than make your own....

This^^^. For $10 the summit ones are nice to have. But if you are missing a size, a grade 8 (preferably) bolt and dremel cutoff wheel will create the exact same thing it about one minute.

Good stuff, I am going to follow you guys' advise. Thank you!

ARP pricing is, as usual, beyond belief. Where in the world do they come up with those numbers?

^^^ Agreed, way more than I'd wanna go

If you just want to clean the debris out, grind 3 flats on an old head bolt. That will allow the grease/gunk to come out & doesn't cost anything.

Ive never had anything crusty enough to feel the need to chase or run a tap down anything and its never caused me a problem. I will spend 2-3 hours cleaning a block after the machine work is done and use a good SS brush in all holes. Brake clean each hole and blow them out then after the 2-3 hours do the finial big soapy wash. So myself have never seen the need to chase every thread, hole, ect.

If you just spent $1700 on manchine work on a block Id hope the shop might of done this already if it was needed.

Not unless you tell them to and pay them to do it. Even then they probably wouldn’t do it. You do know that the holes aren’t tapped the whole way to the bottom during manufacturing of a stock block, right?

Before I reply to what I think I should reply,

"You do know that the holes aren’t tapped the whole way to the bottom during manufacturing of a stock block, right?"

In your opinion whats the significance of that?

Proper torque I’m thinking but what do I know. Just a self taught engine builder here

i agree with pittsburghracer as i have seen/blown out head bolt holes that still have cuttings in them. pull a front pump apart on a 727 and blow out the holes that hold it together but b sure to have goggles or face mask on.

Thank you for your reply and I understand that reply to a point but every arp stud ive ever installed has never had a thread left exposed on the stud and put in hand tight as arp says do not tq the stud in the hole, finger tight and ive seen some people go as far as it will go them just a hair back. But maybe you have encountered holes not drilled/tapped fully.

One thing I have noticed I dont like on some mid 70-s blocks, although my dislike dosent mean its wrong is but you can tell when they drilled and tapped the holes for the main caps in the block and they did it so forcefully it turned the immediate area around the holes black from heat.

I wont drop the shops names because of the bashing ways of the internet but some machine work ive had done by well known mopar shops, ex racers, then machine shop owners that involved areas concerning the mains and caps and such upon align boring and honing, none ever questioned or suggested to tap out more material when I take them a studded block to work on. But I also take them already hot tanked and cleaned blocks.

But I understand why people do it and do so on more crusty core blocks that have been in the elements for a while or are in humid areas.

I bought a set of thread chasers from Jegs many years ago. Have used them on many builds with no problem. Chuck them in my drill on slow speed . No taps ever!!!. There is no reason to use a tap, why would you want to cut metal out of a torque holding surface ?

as a former machinist of 42+yrs, i have done this many, many times on odd size female threads if a chaser is not available, or i needed a job completed without enough time to procure one.
a dremel is nice, but if you don't have one, a hacksaw will, and does, work.
one thing to watch, however, if you don't want to bottom tap your female holes. [yes, that is the proper nomenclature ! i can hear the jokes and comments already.] make SURE your aftermarket bolts or studs do not bottom out on the existing threads. this is especially important for using bolts. even 1/2 a thread can give you false torque readings, plus bad clamping loads.

^^^ are you sayin just to check thread engagement/shank protrusion so the bolt does not go all the way to the bottom (which I certainly see how that would appear to be torqued/tight but not near enough clamping load in a borderline deal. this block was baked clean & looks pristine & what is behind this is in some prior SB builds the head gaskets were not compressed to what felpro says they should compress to (& that is with the std torque amt on the OE head bolts, I forget the #) & that got me thinking that I want to avoid that in this 408 build with .040 cometics that I want to get .040 quench.

For me personally, as a non professional, if the bolt will thread through to the bottom with little resistance, I am good. That usually means with my fingers, not a wrench. If the bolt meets enough resistance that I need a wrench, I will chase the threads until it runs in finger tight. Whether that means with a tap, a thread chaser, or a grade 8 bolt with slots cut doesn't matter much to me. It is usually just the one time. The HF taps and dies have gotten me there for years with no problems. Not bad for the $15 of so I paid for them. If the bolt happens to bottom early, I just throw a washer or two under the head of the bolt. This may not be the professional way to do it, but I have never had an issue doing it this way.

I usually make sure the head bolts will run down all the way without the head gasket or the washers in place. If they will all run down with a small amount of torque without the head gasket and washers, then I feel that they will torque down fine with the head gasket and washers. Just cheaper and easier for me rather than having a bunch of different expensive taps.

Just my

^^^ Dave that is top notch info, thank you!

dave gave great info for sure. as you said, your gaskets were not compressed correctly. that could be caused by either the fastener being a touch too long, or the threads not deep enough by a tick.

Had to use mine today. I was mocking up my heads & rockers to check the pushrods and noticed some of the long head bolts didn't screw in easily. Ran the chaser down every one of those holes and some questionable "stuff" came out. Wondering if water from the leaking head gaskets seeped into them without my realizing it and caused the corrosion.

Agreed, nothing can be assumed/taken for granted.

I've always used taps to clean existing bolt holes, I hadn't heard of or seen a thread chaser until I move to Oregon in 2006
If the existing hole is cut properly the tap shouldn't remove any additional material, correct
As far as what brand to use I have a set of old Craftman, Vermont and several other brands I've bought over the years. The Vermonts seem to break off easier than any others

cut [regular] taps can actually start crooked [it doesn't take much] even if it feels "right", and make the threads oversize.
best to use chasers.