Newbie Question on Die Usage/Bolts

[jamison]

Everyone has to start somewhere. I'll be receiving a GearWrench 114 piece Tap and Die set for Christmas due to the combination of low price and variety. I figure once I've saved enough and learned enough to build my own garage and shop, I'll invest in higher quality taps and dies in addition to collecting more variety of sizes in plug/taper/bottom varieties.

However, my question is, where the hell do you find blank bolts with hex heads (no threads)? Google hasn't helped, but maybe I'm just not looking with the proper search terminology for this type of item.

If these aren't available, I imagine dies aren't used terribly much by machinists when compared with taps? You would just be using them on studs and a few random machined piece (not bolts) that you come across which needed threads, right? As far as I know, if you have a lathe, you'd cut threads on that?

Finally, what is a high quality tap and die manufacturer. For example, if you're buying Snap-On tools, you'd by _______ taps and dies.

Any help or insight into specific real-world jobs where dies are used would be greatly appreciated; thanks!

 

[Cheap5.0]

My in law had 40 years of machining work at GM/Ford, he loved his williams tools.

edit: just gave him a call, he said "any kobalt spiral cut or titanium coated set is a nice set".

 

[fourjeepin]

I use them to clean up the threads on a bolt. Or when you need the threaded portion to be longer. I don't use my tap & die often, but they are necessary.

 

[dwp99]

Dies can be used to make threads farther up a bolt or for threading round stock. I've got an old craftsman set of tap and dies that go up to 1/2".

You can check the MSC website for quality tap and dies. http://www1.mscdirect.com/cgi/nnsrhm?cm_re=tpnv-_-home-_-home

 

[Heavy Metal Doctor]

We have taps and dies from 4-40 to 1" NPT for what we do.
I occasionally run into a fab job where I do use a die to cut threads on round stock, but it's pretty rare. Most die usage is for cleaning up damaged threads or for extending the length of the threads up the shank of a bolt for some reason. Taps get used a lot more often for both repair of existing threads and making new mounting holes for just about anything you can imagine.

As to which taps and dies I use: I know there are plenty of other brands a lot cheaper, but we have a SO set up to 1/2" for the shop just for the convenience / warranty. Break a tap - get a replacement for free.
I also have plenty of hardware store stuff - Hanson, I think is he brand they sell. Along with whatever I can source quickly to get a job done - stuff from Grainger mostly.

I have never heard of "bolt blanks" being sold with a head but no threads even when I was around machine shops. I started out as a machinist myself. Even with a lathe, cutting threads with a die after turning the material to the right diameter is faster and easier in most cases than setting up the lathe for cutting the threads.

 

[Trucky]

I've never heard of bolt blanks either... if we need a specialty thread, we make it ourselves. PITA, honestly. I much prefer to thread holes than round stock.

If you're looking at "high quality" taps and dies... you're looking at a lot of money. Honestly, stick with that set for a while. It is not worth going to *the* brands (OSG, Greenfield, etc.) for simple shop usage. For example, a 3/8-16 hand tap (4 flute plug) from OSG will run you 15$, and that is the cheapest you'll probably find. Go up in material, like cobalt, and you're looking at double that, easy.

 

[racingtadpole]

I've never heard of bolt blanks either....

I had a box of M12 bolts at work that were all devoid of thread. Every single one of a box of 100 had no thread. Which means its been through two lots of quality control (at the manufacturer, and at the company that plates them for us). They are now sitting on a shelf in my shed waiting for me to concoct a project where I need to use 12mm solid rivets

LIke everyone else has said, I dont use the dies all that much and when I do its generally for tidying up or making longer.

 

[Jack Burton]

However, my question is, where the hell do you find blank bolts with hex heads (no threads)? Google hasn't helped, but maybe I'm just not looking with the proper search terminology for this type of item.

If these aren't available, I imagine dies aren't used terribly much by machinists when compared with taps? You would just be using them on studs and a few random machined piece (not bolts) that you come across which needed threads, right? As far as I know, if you have a lathe, you'd cut threads on that?

Finally, what is a high quality tap and die manufacturer. For example, if you're buying Snap-On tools, you'd by _______ taps and dies.

Any help or insight into specific real-world jobs where dies are used would be greatly appreciated; thanks!

A hex head blank would be a pain in the *** to thread because there is no easy way to chuck it in a lathe. So you'd have to put it in a vise, file a chamfer, and then go to town by hand.

You could chuck it the opposite way with the head towards the tailstock and cut a lathe-driven thread but you'd be limited to about 1.5" worth of thread without a center on it. Not really worth it.

You are correct that machinists tap a hell of a lot more than they thread simply because bolts are small and easily available while threaded holes are generally part of a larger object.

I have no idea what brands of dies are considered "good" these days. Check out travers.com I'd stick to something American made though. Machinists generally use the round adjustable dies as opposed to the fixed pitch diameter hex pattern dies you see in Sears and such. That's because some threads will occasionally be called out as loose or tight, class 1 and 3 respectively. These are the round dies, with a hex head screw to adjust pitch diameter and a dimple to accept a die handle.

As far as I know, on an average manual machine any stock roughly over 5/8" would be cut with the lead screw. Anything under that would involve a die, low RPMs and practice.

 

[bad_idea]

If you want to spend some money on threading tools, buy a set of thread chasers. Thread chasers are for cleaning existing threads. Using a tap or die to clean threads makes for a sloppier thread because it removes metal as it also cleans the threads. A thread chaser doesn't remove any metal from the threads, so you maintain the same tolerances the piece was manufactured with.

My father recently bought this set and spoke highly of it.

 

[jamison]

If you want to spend some money on threading tools, buy a set of thread chasers. Thread chasers are for cleaning existing threads. Using a tap or die to clean threads makes for a sloppier thread because it removes metal as it also cleans the threads. A thread chaser doesn't remove any metal from the threads, so you maintain the same tolerances the piece was manufactured with.

My father recently bought this set and spoke highly of it.

Yup, I already own that set and haven't used it yet, but I do like it based on inspection alone. My 1987 project Honda actually had screwed up threads on the oil drain plug, so next change I'll be trying to clean that up (haven't checked the sizing, hopefully I have the proper chase tap).

I appreciate everyone helping me out, as it was all very informative information. I'm going to be keeping this set for a long time, but my dream is to build a 100x30 custom detached garage/shop after I save the cash and learn to the point I would properly utilize such a space. That's when I'll be building a machinists playground, with every tap, die, bolt, nut, "consumable", and all other relevant materials you would ever reasonable require for a project.

Basically, a big building with toys for all of my friends and family to enjoy themselves. Thankfully, my career looks like this will be a reality someday, within 10 years or so. When I do it, there will be a thread on this forum documenting the build.