Has anyone ever tried taps of the same size say 3/8-10 but starting with smaller OD and working up till you get to 3/8. just like drilling only using taps. I would think it would make a very good thread but don't know if they can be made that way. Maybe dies too?
Taps
- Thread starter briz
- Start date
briz said:
The taps I have are the same od for the most part, so I don't know if anyone does that or not. Sometimes I bore My holes instead of drilling, but when I drill, I do step drill the hole by starting small and making a few bit changes until I get to the size I want. If I want to create a snug insert, then I use a slightly under size bit before tapping the insert. The opposite for a looser fit, but I like them slightly snug Myself.
Greg
briz said:
No problem, Just wish I could be of more help.
BTW, The best way I have heard to cut wood threads is with the use of a grinder/rotary tool, and actually grind them, rather then tap them. My experience with tapping wood, is that a certain ID works best without any tearout or other issues, and kind of limits the amount of tweaking you can do, as where other materials tap well enough to allow for more ajustments making it easier snug the fit. I would think that the grinding method would also give you more flexibility with wood, as well as cut nicer threads.
Greg
Yup that's the way I'd like to cut them but I don't have change gears on my lathe -- it's one of Chris' with all the bells and whistles but no thread cutting gears. Do you know what this Frog thing is. I thought I heard someone say it cuts threads but I might be way off base. Just never heard of it and if it does will it cut all the threads used for a cue? Thanks a lot for your help.
Brian
Brian
briz said:
One of My lathes is a hightower deluxe also, yes I have heard of the frog, It's basically a small controller to control stepper motion from what I know of. I once asked Chris If he knew anything about them, and if it would be feasable. I believe He mentioned something about the ratio of the gear rack not being exactly suited for the frog, but they do work with the correct ballscrew, so where there is a will, I'm willing to bet there's a way, just depends on what all your willing to go through to fabricate something to get the job done. Hopefully He will see this and can chime in about the issues with using one, as He would know better then I. Apparently It would not be as easy as just a bolt on operation though, and I don't know what all size threads it can be programed to cut even If there was no gear ratio issue.
Greg
Thanks Chris. I went to the frog site and it seems they will no longer be making them due to family things. Said they might still have parts and are thinking of selling the rights for it. Don't know when this happened -- thought you might want to know.
Brian
Brian
Tap Sizes Oversize/Undersize
Taps are available in up to plus or minus .005 inches sizes but most common are plus sizes to compensate for shrinkage due to heat treating or coating. 3 stage precision ground high speed steel hand taps using high performance tapping fluid like Chromatap will give micro finish exact size ( sometimes undersize ) thread. A powdered metal machine tap will give almost as good a thread using high performance tapping fluid and last a lot longer. For soft materials like brass and aluminum roll forming taps ( different tap drill size ) work well with high performance tapping fluid. Generally speaking the better a tapping fluid works the more toxic it is. For an interferance fit thread a straight pipe tap could be used but no oone does this because its non-standard and wear from usage would result in regaular fit thread.
Taps are available in up to plus or minus .005 inches sizes but most common are plus sizes to compensate for shrinkage due to heat treating or coating. 3 stage precision ground high speed steel hand taps using high performance tapping fluid like Chromatap will give micro finish exact size ( sometimes undersize ) thread. A powdered metal machine tap will give almost as good a thread using high performance tapping fluid and last a lot longer. For soft materials like brass and aluminum roll forming taps ( different tap drill size ) work well with high performance tapping fluid. Generally speaking the better a tapping fluid works the more toxic it is. For an interferance fit thread a straight pipe tap could be used but no oone does this because its non-standard and wear from usage would result in regaular fit thread.
Trueheart said:
Thank you very much Trueheart. Sounds like you have a lot of experience in machining. So it sounds like I can order taps undersized and cut up to the size I need in increments. Is that right? But since I'm going into wood, no cutting fluid allowed. I don't think .005 under is enough though. I want the tapped hole to be as true as possible with out any chipped threads. That's why I thought starting with a smaller tap diameter and working up to where I want might do it. Kind of like drilling then boring then reaming. However not being anything near a machinist I'll gratefully accept any knowledge you have. And what did you mean by them shrinking in the heating process. I thought metal expanded when heated. Like I said -I'm no machinist- so I hope you'll be patient with my ignorance. Took a lot of trips to the dictionary for this one.
Brian
> When you look at the shank of any brand new tap,there is a fit class designation on it. The standard for these is the letter H or L,for High limit or Low limit. This is usually right behind the letter G,for Ground Thread. These standards have been in place for years,and haven't changed. For all UN-C or UN-F taps under 1" fractional or machine screw size,the range for L1 thru H6 is .0005 undersized to .0030 oversize. This assumes that you are using ready-made taps from a hardware store or industrial supplier,as opposed to having a custom tap service like Widell make them to your specs. In a case where a undersized tap might be desirable to achieve a tight fight such as the threads that hold a brass insert,it would probably be just as easy to machine a slightly oversized insert,and use the standard H3 tap for 7/16-11 or 14. The reference for this information is the 27th edition Machinery's Handbook,which will teach you things you never knew about screw threads,taps,grinding procedures for tools,things you must know to safely operate the machines that make cues as well as procedures used in the process. Tommy D.
Tommy-D said:
Thank you Tommy-D. I think I know what you're talking about. I do have Machinery's Handbook but I think it's the 26th edition. I bought it quite a while a go and need to brush off the dust and get back into it. It's a great book and I was really into it but you know how things come up in life and side track you. Thanks again for you're help.
Brian
> Other than expanded math coverage,and a nice section on CNC,there really isn't much difference between the 27th edition I bought last July and the copy my grandfather gave me which was printed in 1951,the 14th edition. As far as feeds/speeds for various woods,the actual cuemakers here would be a better source for that info than me,along with the other stuff you mentioned. I gave the info on taps because I try to share what little I do know in return for learning things from others here,and because I aced the test on taps and tapping procedures. I had to,because I wasn't allowed to use one until I did,my instructor makes sure you know what you are doing before you take a chance on hurting yourself. Hopefully,someone else will chime in here,I am curious to see exactly what the proper feeds/speeds are for woods. In the little I have done,I have noticed that maple tends to shred when using regular brazed carbide or indexable insert tools,and actually got better results on my machine with impeccably sharp HSS tools. Without this info we both seek,one of us might assume the cutting speed/feed rate for soft aluminum would be ok for bacote for example,and get a rather nasty surprise when the feed is engaged. Until this info is discussed here,I'd honestly be scared to try it. Tommy D.
Tommy-D said:
I think you're right about the HSS Tom. I had a friend who knew a lot more about this tell me for wood to use very sharp HSS and fast speed. They're not very expensive and sharpen easily. Thanks again for the info.
PS--- Steve Prefontaine was one of the greatest natural talents that ever ran. He just went out there and did it, a shame his potential was cut short.
Brian
Last edited:
Tapping Wood and Soft Metal
Hello Brian
Tapping 101 ( I Am Tool and Die Maker by Trade )
> For wood and general low volume use hand taps are best.
>Hand taps come in three taper designations taper, plug, and bottoming and should be used in that order to thread hole to bottom.
>For the best thread the tap is fully ground and polished, made in North America or Europe of High Speed Steel and this is also most expensive tap. Atlas Billiards sells these as do industrial wholesalers. Long taps are referred to as nut taps and cost extra.
>I use Bostic Top Coat on the tap for lubrication when tapping wood but you must be completely sure the Top Coat is completely dry or it will transfer to the wood and act as a glue release agent. Anything you do NOT want glue or finish to stick to can be coated with Top Coat.
> In wood a smaller tap drill size should be used than metal. The softer the wood the smaller the tap drill size. In metal tap drill sizes 75% of full thread depth is achieved.
>Choose as small a tap handle as is comfortable as this will give you best feel and make it less likely you break the tap.
>Hand Taps must be advanced 3/4 turn the backed off 3/8 turn ( roughly )to clear chip or threads will rip out. In metal you can hear and feel the chip snap off. If the tap is getting hot you are tapping too aggressively. In wood you may have to retap several days later as wood may swell as compression of tapping is released.
>Machine taps thread in directly like a screw but should be guided by a machine ( hense name Machine Tap ) like drill press or lathe tailstock. Usually too aggressive for wood. Machine taps specially made for aluminum ( cutting anngles are greater ) are best choice to tap wood if you want to try a machine tap.
>For soft metals like brass and aluminum taps called roll forming taps are best. Roll forming taps do not cut threads they sqeeze the metal into shape thus giving a stronger cold worked thread. They also generate a lot of pressure while threading and will distort thin walled objects like tubing. No use in wood as wood will rebound from roll forming compression except possibly, big maybe, have not tried, use at own risk, may result in long term cracking problems, to glue in threaded pins with polyurathane glue.
>The Machinery Handbook contains detailed information on all threads but unless you are a machinist or tool and die maker will only put you in information overload and confuse you. Best is get a tap manufacturers hand book from your industrial supplier. Dormer makes top quality taps and the best handbooks.
>When metal is heat treated sometimes it shrinks others times it grows depending on the reaction with the atmosphere and quenching medium and it always distorts in varying degrees so oversize taps are often used on tool steel items. The threads cut are oversize in every way so are a looser sloppier fit.
>Did you hear about the guy who swore and cursed and wished he were dead when he finaly discovered it was a left hand thread?
>Any questions glad to answer.
>Seasons greetings and a happy new year.
briz said:
Hello Brian
Tapping 101 ( I Am Tool and Die Maker by Trade )
> For wood and general low volume use hand taps are best.
>Hand taps come in three taper designations taper, plug, and bottoming and should be used in that order to thread hole to bottom.
>For the best thread the tap is fully ground and polished, made in North America or Europe of High Speed Steel and this is also most expensive tap. Atlas Billiards sells these as do industrial wholesalers. Long taps are referred to as nut taps and cost extra.
>I use Bostic Top Coat on the tap for lubrication when tapping wood but you must be completely sure the Top Coat is completely dry or it will transfer to the wood and act as a glue release agent. Anything you do NOT want glue or finish to stick to can be coated with Top Coat.
> In wood a smaller tap drill size should be used than metal. The softer the wood the smaller the tap drill size. In metal tap drill sizes 75% of full thread depth is achieved.
>Choose as small a tap handle as is comfortable as this will give you best feel and make it less likely you break the tap.
>Hand Taps must be advanced 3/4 turn the backed off 3/8 turn ( roughly )to clear chip or threads will rip out. In metal you can hear and feel the chip snap off. If the tap is getting hot you are tapping too aggressively. In wood you may have to retap several days later as wood may swell as compression of tapping is released.
>Machine taps thread in directly like a screw but should be guided by a machine ( hense name Machine Tap ) like drill press or lathe tailstock. Usually too aggressive for wood. Machine taps specially made for aluminum ( cutting anngles are greater ) are best choice to tap wood if you want to try a machine tap.
>For soft metals like brass and aluminum taps called roll forming taps are best. Roll forming taps do not cut threads they sqeeze the metal into shape thus giving a stronger cold worked thread. They also generate a lot of pressure while threading and will distort thin walled objects like tubing. No use in wood as wood will rebound from roll forming compression except possibly, big maybe, have not tried, use at own risk, may result in long term cracking problems, to glue in threaded pins with polyurathane glue.
>The Machinery Handbook contains detailed information on all threads but unless you are a machinist or tool and die maker will only put you in information overload and confuse you. Best is get a tap manufacturers hand book from your industrial supplier. Dormer makes top quality taps and the best handbooks.
>When metal is heat treated sometimes it shrinks others times it grows depending on the reaction with the atmosphere and quenching medium and it always distorts in varying degrees so oversize taps are often used on tool steel items. The threads cut are oversize in every way so are a looser sloppier fit.
>Did you hear about the guy who swore and cursed and wished he were dead when he finaly discovered it was a left hand thread?
>Any questions glad to answer.
>Seasons greetings and a happy new year.
Great Info
Merry Christmas and Happy New Year to you too Trueheart.
Really great info TH. Thank you much for your time and expertise. As I think I mentioned I haven't been doing any of this for some time and knew little to begin with but the way you explain things gets me itching to get a place to start again. Have a good one.
Brian
Trueheart said:
Merry Christmas and Happy New Year to you too Trueheart.
Really great info TH. Thank you much for your time and expertise. As I think I mentioned I haven't been doing any of this for some time and knew little to begin with but the way you explain things gets me itching to get a place to start again. Have a good one.
Brian
taps
You're getting some good advice,but I hope if you're doing cue work, you don't use hand taps, in a hand held handle. THE most important thing about making or repairing cues is that the joint screws MUST be drilled & taped exactly in the center, of the end of the cue. THAT CANNOT BE DONE WITH HAND TAPPING TECHNIQUES. You must drill & tap with the tap chucked up, in the tailstock. You can use a combination of threading with the lathe turning & finishing the thread by turning the headstock by hand, til you get to the bottom of the hole or turning it all of the way to the bottom, by rotating the headstock with your hand hand...JER
You're getting some good advice,but I hope if you're doing cue work, you don't use hand taps, in a hand held handle. THE most important thing about making or repairing cues is that the joint screws MUST be drilled & taped exactly in the center, of the end of the cue. THAT CANNOT BE DONE WITH HAND TAPPING TECHNIQUES. You must drill & tap with the tap chucked up, in the tailstock. You can use a combination of threading with the lathe turning & finishing the thread by turning the headstock by hand, til you get to the bottom of the hole or turning it all of the way to the bottom, by rotating the headstock with your hand hand...JER
BLACKHEARTCUES said:
Hi Jer,
Thanks for the info. It's been a while since I've done any tapping and you're right--- that's the way I did it with the tap in the tailstock and turning the headstock. They didn't come out to bad at all. When I get a place to really work and have the money I'll get a metal lathe so I can grind them--- saves a whole lot on the arms. Have a Merry Christmas and Happy New Year.
Brian