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Tap and die?


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I have a tap and die set that I bought when I was your age. I cannot remember the last time I opened it, and I tap holes all the time. Unless you buy a set from an industrial supplier the taps are going to be junk and chances are you will never use 80% of the taps. Taps are one of the things you should buy as you need them. As Southshore said a broken tap can cost you way more than the cost of a tap. When you buy your taps buy two of the sizes you need and buy the tap drills as well. That way you will not be tempted to continue using it after it is dull or a spare if you break one. Using the wrong sized drill is a good way to break drill bits or have weak threads.

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one of the first tools I bought when I got out of the army was a tap and die set (cheap one) I still have some that are un used I have added to my collection but just adding the one I use. if I were starting out now I'ed just buy the one when I needed to tap a hole I think I'ed get the drill bit and tap as a set along with a die and die stock and I'e look for the hex die and die stock

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When I had my shop I bought a couple of boxes on Ebay from a guy who was getting them from Boeing surplus sales. 5# of taps for $30. They are all high quality USA made spiral point taps. Boeing uses a tap for 6 holes then replaces it.

Buy what you need instead of a set for now. Taps, break, and do wear out fast on some materials. I have taps at work the may go 20 holes before they get too dull to hold tolerance, or surface finish. We use MSC, and a couple of locals. My shop used MSC, J&L, Rutland. Get on their mailing lists as there is always a special running on taps.

I use spiral point taps so I can power them in the mill, or lathe. This design throws the chip to the front, no back n forth to break chips, just feed them one direction.

Spiral flute draw the chips up, and out of the hole. They can also be powered into the hole. harder to remove when they break having spiral flutes.

Fluteless thread froming taps are a powered item, not for hand use.

Coatings. I just use bright,oxide, or whatever is the special that month. For what I do I don't see enough difference in performance to pay extra.

Removing broken taps. I drill them out with solid carbide drills. Takes a couple of minutes in a mill, or lathe. HSS taps drill like butter under sharp carbide. Setup MUST be rigid though. In cast iron through holes I have blown them out with a OA torch, some use plasma cutters now. There was a thread on broken tap removal last year.

Cutting fluid. I use the same cutting oil that the CNC machines use. Tap Magic is good, Jelly Belly had a green water soluble paste that worked good on stainless. In a pinch I have used Brake Kleen,and carb cleaners that have chlorinated solvents. If it is flammable it usually works :D The magic in Tap Magic used to be 1,1,1 Trichlor beautiful tapping fluid IF you can find some, but you need great ventilation to use it. DON"T USE ON ALUMINUM! Makes purple fumes, and welds the tap into the hole. That wasn't fun. Never did get the tap out of that plate. <_< Anything is better than nothing. Copper will just need any oil to avoid galling. I have found that a thicker oil that hangs on the tap some is better than say WD-40. Steel is fairly easy to thread, but stainless can be a beotch to do depending on alloy, and type of material IE; 304, angle, channel, etch. 303 machines like butter. The structural shapes have a hard surface layer that can wreak havoc on a tap.

Drills, and drilling. GOOD quality drill set. Drills come in more than fractional sizes. A complete set is usually 115 drills. 1/16"-1/2" by 64ths. A-Z letter set, and 1-60 number set. They go down to 80 but that is reeeeeeeeealy tiny.

Example;

Tap drill for a 4-40 is a number 43 number drill. Tap drill for a 3/8-16 is a 5/16" fractional, and the tap drill for a 5/16-18 is a letter F drill.

Metric can use close "regular" drills but they do have their own metric tap drills.

Tap drill charts are available, and sometimes given out free.

Drilling steel, nothing special. Stainless needs a steady feed. DO NOT let slip on surface! That will work harden the surface, and you are not getting through it on that side unless you have a better drill. Cutting speed is slower than steel. Brass likes a zero rake edge on the drill (straight up and down) otherwise it likes to grab, and suck the drill into it. Speed is faster than steel. Copper likes good sharp bits with lubrication, otherwise it will gall the chips up. Cuts faster than steel. I drill a lot of copper at work. Cast iron drills very easily nice little flake chips no strings.

Drilling Speed is not a set amount, but a recommendation. There are times when I have to go way below the rated speed, sometimes a lot faster. Just depends on a lot of factors: material grade, rigidity, pilot hole size, type of drill flute, point shape, point angle, etc.. You learn to listen to,watch the chips, and feel the drill working. Matter of fact a lot of machining is done by observation. Knowing what to do to get the desired results when by the book isn't working.

Tap handles. I have a set of Starrett 2 jaw tee handles that I really like. At times the old flat tap handles work better for a given situation. The tees have a center on the top for a tapping guide to enter. I use them when tapping in the lathe, or mill. Depending on the size of the tap, or material I usually just chuck up the tap, and power it through. I use the tap handles for bottoming, taper, and other nonpower type taps.

Dies. They can be square, round, adjustable, and hexagonal. You will need a die stock to fit whatever shape you go with, or like me you have all of the above. Adjustables are nice for some applications.

Long winded, but I did use paragraphs at least :P

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Biggun that's some spheil, it near wore me out just reading it. :D

Would you please be so kind as to e-mail it to me as I would like to re-format slightly, print and stick it up as a tutorial above the drill presses in the shop, if thats ok with you of course! B)

Thanks Ian

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One thing that hasn't been mentioned is that there are different types of taps. They all work better than the standard gun tap for the job the were designed; for example a spiral bottoming tap pulls the chips up and out of the hole like a drill. keep this in mind also

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another thing you might find handy is a screw checker both metric and inch ...comes in handy if your not sure of the size or if its a fine thread or coarse http://www.generaltools.com/Products/Quick-Check-Screw-Gage__714.aspx
http://handtoolsmadeinusa.hotfridayshopping.com/metric-screw-checker-8mm-to-14mm-made-in-usa/
also a thread pitch gage

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Another red flag is is junko die cast wrenches and die holders. I've had cheap sets where the steel ain't too bad in the taps and dies, but the wrenches and holders were crap, savings: 0..............mb
Also, I've found that sense I converted all my RH taps and dies to LH I no longer pop the buttons off my shirts with the wrenches...........Believe it or forget it

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A quick thanks to BIGGUNDOCTOR for the quick overveiw on the different TYPES of taps as this is very important much of the time and figures in greatly when it comes to tap types and tap failure. Much has been mentioned here to get you started well and I would only recommened that you get a hold of a Machinest Handbook(as new an edition as possible) for a little Lite reading. once you learn how to sort through all the info available in it you will have a lifetime guide to nearly every situation concerned with tap and die, drilling, machining, screws, nut, bolts, metal properties, etc,etc,etc, though never discount the aspect of good quality advice and instruction from others with experience. Wes

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Out on Long Island There are lots of small machine shops. I have bought a number of took chests over the years It is a holdover from when Grumman aircraft used to do most of its manufacturing here. If you go even further back there was Fairchild Republic aircraft was here. Most of them got their starts working for one of these two company's. Sadly not lots of large forging equipment to be found around here though.

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A Machinery Handbook is a must have, and there are some used copies out there. Check out some used book stores. A new one will set you back around $75 last I looked, but it is the machinist's Bible. The Kennedy machinist chest has a drawer in the middle that is designed to hold the MH, that is how important that book is.

I picked up a chest with a 3 drawer riser from a guy who was retiring. He told me that the other guys looking at it were tool dealers, and he would rather sell it to someone who was going to use the tools. He even included some he made while he was at CalTech. The last radio telescope filter he worked on had an opening punched into it that was 80x90 microns, and the engineers were working on an adjustable shutter for it :blink: That is the chest I currently have at work. It took both of us to haul that little chest to my truck it was so full. No taps, etc, but full of indicators, mics,and small hand tools. Paid $550 for both. I took and inventory at home, and came up with over $6,000 if bought new through the major dealers like MSC. There are tons of good used tools on the market. I was picking up good mics, and indicators (Starrett, Brown and Sharpe, Tesa, etc) at auctions for $10-$25 ea. basically 10 cents on the dollar. Hit some machine shop auctions,and you can walk away with some great deals if you do your homework.

The Starrett triangular (3 blade sets) thread pitch gage is a nice one. The cheap ones can be tough to use as they are not that precise in their thread forms.

Ianinsa-inbound.

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Now that it appears everyone is finished forwarding knowledge, let me list some items I can part with to donate to the situation. I have some brand new boxes of taps I was planning on using when I started my own machine shop and that idea has been put aside for some time now and doesn’t look like it will spawn.

I can donate 3 taps of every size of the following: 4-40 unc 6-32 unc 8-32 unc 10-32 UNF 1/4-20 unc 5/16-18 unc 3/8-16unc 1/2-13unc. Threading dies I have very few of.

The #10 is a fine thread because the 10-24 coarse thread has a small root diameter for the thread size and when tapping strong materials like steel, the coarse thread can be more prone to breakage. So when I design things made out of steel, I choose the fine thread for #10 screws.

I also have two extra T-handle tap wrenches in good shape that will cover the above size ranges. These tap wrenches can be used up to the 1/2” size and are good for starting the taps straight.

I have an entry level machine shop textbook left from my years of teaching so I will put that in along with its work book. It’s written by a capable author and easy to read for self educating. I’ll put in a Starrett tap drill fraction decimal reference card so you can quickly identify the proper drill sizes for the taps. That should set you up ok for tapping once you get your drills if you don’t already have them.

We’re a little busy here so it will be next week before the package can be taken to the UPS port. I’ll have it sent to the Custer farm address listed on the web and put to your attention. If there is another address you prefer, PM me and let me know. You owe me nothing in return because so much to do with blacksmithing is expensive and overcharging is something you don’t do. Good luck! Regards, Spears.

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We’re a little busy here so it will be next week before the package can be taken to the UPS port. I’ll have it sent to the Custer farm address listed on the web and put to your attention. If there is another address you prefer, PM me and let me know. You owe me nothing in return because so much to do with blacksmithing is expensive and overcharging is something you don’t do. Good luck! Regards, Spears.



Seeing as how it`ll be a bit before you get that flat rate box out we should just send our contributions to you so you can fill that box properly right? :D
Where`d you find the address?I got some larger taps and a few dies as well as a die stock I can do without.
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It was easier to write than "@$%&@*# Bolt remover". :blink:


He's a good Christan boy don't ruin him. I spent 6 years in Christan school It only took one summer in a steel shop to ruin me.

Btw one way to get out broken bolts is to plug weld a nut to the top of the busted stud. The heat of the weld helps to loosen it up. some times if there is anything to grab you can just twist them out with a with a vise grip.
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There are two things I never go cheap on that is taps and chisels! I like taps and dies made by Hanson. They are strong and hold a edge well. I would buy just the sizes you are going to use most often at first, then expand as you need them this will spread the cost out over time. So it won't seem so bad. As for lube, I like sticky oil for taps and dies. I would buy cutting oil at a place that treads pipe or in a pinch I'll use chainsaw bar oil. Remember to back off the tap or die as you are cutting and clean the chips off, this will save you lots of broken taps. Also there are different styles of taps( first cut, second cut, bottom and gun..ect) know what you need when you order them. Hope this helped. TC

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I have one of these It is super handy. http://store.huot-store.com/tool-storage/product/13590.html You can find them used on Ebay from time to time.

That is a really nice organizer. I use the cheaper alternative- tap & drill stand at the bottom of this page: http://www.mcmaster.com/#tap-organizing-stands/=alfnzj
It holds drills and taps from 1/2" down to some teeny sizes I never use. For each size, it holds NF taps and tap drills on one side, NC taps & tap drills on the other, and nominal size drills down the middle.

I agree with buying good quality taps & drills, and would say that good drills are even more important than good taps. One thing I didn't hear mentioned is a drill sharpener... that's something I couldn't live without. Even top quality drills need to be sharpened when you use them in a lot.

One other tool that's probably out of scope of this discussion but I'll mention because I love it so much, is a Bosch tapper http://www.amazon.com/Bosch-1462VS-3-8-inch-Tapper/dp/B00181LECS
I can't remember where I got mine- one of the blacksmith supply houses, years ago. It has a clutch just like a tapping head on a drill press... goes through holes really fast without breaking taps.
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He's a good Christan boy don't ruin him. I spent 6 years in Christan school It only took one summer in a steel shop to ruin me.

Btw one way to get out broken bolts is to plug weld a nut to the top of the busted stud. The heat of the weld helps to loosen it up. some times if there is anything to grab you can just twist them out with a with a vise grip.

Brownells sells broken tap extractors http://www.brownells.com/.aspx/pid=15612/Product/BROKEN_TAP_EXTRACTOR
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He's a good Christan boy don't ruin him. I spent 6 years in Christan school It only took one summer in a steel shop to ruin me.

Btw one way to get out broken bolts is to plug weld a nut to the top of the busted stud. The heat of the weld helps to loosen it up. some times if there is anything to grab you can just twist them out with a with a vise grip.


I spent 30 years in steel shops and now I live on a christan school campus trying to unruin me. I hope it doesn't take another 30 years. :huh:
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