 Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me. |
Forum Index : Microcontroller and PC projects : Cutting 3mm threads....
  Page 2 of 3   |
|||||
| Author | Message | ||||
| Bill7300 Senior Member  Joined: 05/08/2014 Location: AustraliaPosts: 159 |
Just to round out the discussion about tapping by hand in the drill press, rather than by attempting to do it under power, even at low speed. Machine taps have already been mentioned. They are the devices intended for use when tapping under power, but they are normally used in dedicated tapping machines or drill presses fitted with special machine tapping heads.From memory, both of those devices automate the backing off process, so it is essentially the same approach as used when hand tapping in a drill press. Bill |
||||
TassyJim Guru  Joined: 07/08/2011 Location: AustraliaPosts: 6283 |
For small taps, I prefer to use a t-bar holder. I find it is easier to hold true.  Jim VK7JH MMedit |
||||
| Paul_L Guru Joined: 03/03/2016 Location: United StatesPosts: 769 |
It looks like the three regulators are on one side of the board and the heat sink is on the other side. Is that correct? Paul in NY |
||||
Grogster Admin Group  Joined: 31/12/2012 Location: New ZealandPosts: 9610 |
Correct. Smoke makes things work. When the smoke gets out, it stops! |
||||
Gizmo Admin Group Joined: 05/06/2004 Location: AustraliaPosts: 5119 |
I hate tapping small holes, especially in aluminium and fine threads. Where possible I use short coarse thread self tapping screws, the type salvaged from discarded appliances. These tend to push the soft aluminium into shape instead of cutting it. Bit of oil helps, and as mentioned above, the initial hole size is key. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
| DaveC166 Regular Member  Joined: 13/09/2012 Location: New ZealandPosts: 44 |
Grogster, I got P&N 3mm starting taps from my local The Toolshed. I also got a ratcheting T-Bar handle from Tradezone for about NZ$30.00 Both companies have branches in Dunedin. Finding a good handle for small taps is not easy, The Tradezone T-bar was about NZ $40.00 . I find T-Bar handles make it relatively simple to cut a straight thread and they are harder to apply excessive force to the tap with the shorter handle, ie you get better feedback when the tap starts to bind |
||||
MicroBlocks Guru Joined: 12/05/2012 Location: ThailandPosts: 2209 |
If you look at the top of a tap there is a small hole or a point. This is used to center it. When i mentioned a drill press i meant to say to use it as a guide! Have a look at this video as it explains it very well. https://www.youtube.com/watch?v=KBrrVnYBPOQ Microblocks. Build with logic. |
||||
| Gizmo Admin Group Joined: 05/06/2004 Location: AustraliaPosts: 5119 |
Clever! The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
bigmik Guru Joined: 20/06/2011 Location: AustraliaPosts: 2950 |
@MicroBlocks, That is an excellent video.. I was going to mention the hole in the top of the tap but I realised a 3mm would not have a hole but the conical point.. The fact the tap wrench has the hole was an eye opener as I never realised that and, as I said, I was in the game for 9.5 years.. You learn something every day.. Note how he backs off to break the swarf shavings!! Kind Regards, Mick Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<< |
||||
| HankR Senior Member Joined: 02/01/2015 Location: United StatesPosts: 209 |
The advice to use a drill press pertains to using it only for alignment, not for powering the tap. Edit: The above was written before I realized there were two more pages of subsequent posts on the topic of threading. |
||||
| HankR Senior Member Joined: 02/01/2015 Location: United StatesPosts: 209 |
That shortfall in tapping technique probably is critical. You can't go too slowly (meaning the slower the better), or back up too much. You can even withdraw the tap completely and blow or flush the chips out and resume tapping. Taking these steps will make all the difference in the world. |
||||
| HankR Senior Member Joined: 02/01/2015 Location: United StatesPosts: 209 |
At no point should the tap feel "tight" in the sense of resisting rotation. Go slow, reverse often, and use plenty of lubrication. |
||||
| Phil23 Guru Joined: 27/03/2016 Location: AustraliaPosts: 1667 |
All that aside; someone's gotta ask, "What is it"? Explore64, Touch screen, Radio thingy with SIM card, other stuff inc speakers & printer connections. |
||||
| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9610 |
It is a replacement security system. This is the new replacement for the old system that was cooked in the October lightning strike from God, which used the old - now obsolete - uALFAT filesystem module that I had a bit of a mission finding temporary replacements for. That system was PICAXE based(28X2) with the filesystem module and a TellyMate chip for B/W video output on a standard TV screen. This one uses the MM+ and a colour touch-screen. Much sexier then the PICAXE system. The old system used a very noisy, big and heavy dot-matrix printer for printing messages. The new one uses a relatively silent thermal printer which is panel-mounted with the LCD to keep things nice and tidy. I have been developing this since December, once we had settled down MOST of the lightning damage - although, we are still fixing up the smaller stuff even now! Looking at the top image, the white module at top-right of the PCB is an ElecFREAKS GSM(Cellphone) module, so the system can send TXT messages to cellphones if needed. Below that, the blue WizNet module is a network serial-port, which is connected to the MM+ console, so that remote admin becomes possible. To the right of that at the top is a small relay(yellow dot on it), and this is a latch controlling power to the network module. If selected within the menus, this latch switches power to the network module to enable it, and I can remote-in to the console via an internet connection. As part of the normal startup procedure, this latch is switched OFF if it is on, so when I am finished, I can just issue a run command, and the network connection will be lost(as the latch will get switched off), and the program will re-run locally. Keeping the network module powered off prevents any network IP sniffing programs from discovering it is there. Naturally, it is still discoverable while I am using remote access, but having the network module powered down normally, makes the chances of anything finding it there extremely remote, as they would have to happen to look for it while I happened to be using remote access. Blah, blah, blah.... Below the latch, is a small stereo audio amplifier for connecting to speakers for WAV file playback - alert tones or WAV files, voice prompts. Not for music.  This system has been through four different designs, as each time I finish the damn thing, the developers here release the next MM+ chip with go-faster stripes! When matherp announced the MMX, I had just about finished designing the board for this one, so I uttered two words at that point, the second of which was: "It!" With the exception of high-quality WAV playback and the new I2S audio codec support, the standard MM+ with the latest firmware supporting WAV playback will do the job beautifully.  Smoke makes things work. When the smoke gets out, it stops! |
||||
Bryan1 Guru Joined: 22/02/2006 Location: AustraliaPosts: 1483 |
Hi Grogster, Only just seen this thread and it's already 3 pages  A few weeks ago I did a job for a mate building his still and drilled and tapped 24 M3 threads in copper. Drilled the holes in my mill to a 65mm pcd and just used a larger drill to chamfer each end of the holes. Chamferring the hole gives the tap a good chance to start rather than no chamfer on the hole. I do have about hald a dozen of those tee wrenchs form a very small one for doing BA taps all the way upto large ones for doing 1/2". Now with a tee wrench it should have a centre hole at the end of the shaft and that can be used as a centering aid. For using in a drill press just get a tap or such that has a tapered point and put that in the chuck. With the work clampd to the drill press bed put the tap in the hole then apply very light pressure so the tap is sitting square to the hole. Now with one hand on the drill press arm and the other turn the tee wrench while keeping light pressure will ensure a square tapped hole is achieved. As far as tapping fluid for ali I just use trefolex but I have seen at work guys cutting ali just rub a white wax on cutting disks. So just stabbing the tap in a candle should be enough for tapping. Now as far as breaking the swarf a general rule for small taps, 3 turns on the first run then break, do 1 turn and break until the depth is required. Cheers Bryan |
||||
| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9610 |
Hi Bryan.  Yes, the length of this thread  has surprised me too. Who would have thought it would get so much attention. I figured a few posts from a few members, but there you go.Thanks for your advice. Smoke makes things work. When the smoke gets out, it stops! |
||||
redrok Senior Member Joined: 15/09/2014 Location: United StatesPosts: 209 |
Hi Grogster; Yes, I have a brighter idea. Don't use "Thread CUTTING Taps". Use "Thread FORMING Taps". Thread Forming Taps don't actually cut the metal. They form or displace the metal to form the thread. They look kind of like a screw thread that is deformed to a somewhat triangular cross section. See: Formdrill Balax Cold forming technology And many others. The biggest advantage is the tap is much stronger than cutting taps. There is more meat in the tap. they don't have the chip capture volume that cutting taps need. Also, the thread is stronger as they somewhat resemble "Rolled" threads. The drill is not the same size though. redrok AD0TJ |
||||
palcal Guru Joined: 12/10/2011 Location: AustraliaPosts: 1993 |
Very interesting indeed, I must say I have never heard of them. A bit like cutting a thread with a self tapping screw. I had a look on Hare & Forbes website (The largest machinery house in Oz) and they don't stock them, so I sent them an email with a link to this thread. It will be interesting to read their response. Paul. "It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all" |
||||
| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9610 |
I've never heard of them either. MOST interesting. Perhaps something not so widely available down Australia/New Zealand way? Would be very interested to hear from other members about those ones. I have not got around to ordering my tap sets yet, so now is the time to throw this idea around. Smoke makes things work. When the smoke gets out, it stops! |
||||
| Bill7300 Senior Member Joined: 05/08/2014 Location: AustraliaPosts: 159 |
Aviation A&N standard bolts are all roll formed threads. Bill Bill |
||||
| Page 2 of 3 |
|||||
 Print this page |
 |
The Back Shed's forum code is written, and hosted, in Australia. | © JAQ Software 2025 |
