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Black Forest
10-17-2011, 02:01 PM
I made this today. I used a MT5 taper with a 34mm diameter shaft. The die holder was made from a piece of 56mm hydraulic ram rod.

I looked for a design to copy but didn't find any so I just built what I thought would work.

So any suggestions as how to improve it would be welcome!

I thought about making it out of Brass and engraving it but I had no time!!!!!!!!

http://www.youtube.com/watch?v=DkL4fQIie1o

Davidhcnc
10-17-2011, 02:50 PM
That is good.

How about a travel stop on the lathe bed for the tailstock. Shove the tail up to the bed stop and then your automatic thing will take over.

dockrat
10-17-2011, 03:47 PM
That looks great and works slick but hey, I made mine out of brass. :p I plan on engraving it next week :D

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1390Medium.jpg

Rich Carlstedt
10-18-2011, 07:03 PM
Great idea .
Thanks
Rich

Black Forest
10-19-2011, 12:27 AM
It is not my idea. I saw a picture of a tapping rig posted by JTeirs and made it from what I saw. I changed it a little bit but the idea is not mine!

I have no original idea's!

DFMiller
10-19-2011, 01:32 AM
Ernie,
You do like brass. ;-)
Nice job.
Dave

Ian B
10-19-2011, 03:10 AM
BF,

Nice piece of kit!

I saw that you also have a similar design of tap holder - could you have combined the 2 designs into one unit, by just having one sliding head for dies, one for taps? Or maybe hold the tap chuck in the dieholder? Just a thought.

Ian

J Tiers
10-19-2011, 08:34 AM
It is not my idea. I saw a picture of a tapping rig posted by JTeirs and made it from what I saw. I changed it a little bit but the idea is not mine!

I have no original idea's!


And I got MINE from a book, slightly modified to make it easier to manufacture.

Someone else had apparently posted here a similar device as well, although I don't recall that one.

RussZHC
10-19-2011, 11:18 AM
Just throw this in "here":

http://www.hemingwaykits.com/acatalog/Floating_Reamer_Holder.html

a similar idea w different application...I don't have talent you all do, so this could be the route I go ;)

good to include video, danke.

Black Forest
10-19-2011, 11:52 AM
Now I have to figure out how to make the pin jump ahead when I reach depth so all I have to do is reverse the spindle so I won't have to crank the tailstock ahead to pick up the pin again.

I have draw a few ways to do it but they are quite complicated.

Anyone got any ideas how to make it so you only have to reverse the spindle.

Sir John posted in another thread about one way roller clutch bearing.........

I am not sure how they work or what the concept is actually.

Black Forest
10-19-2011, 11:54 AM
I just realized on DockRat's die holder he used the tool holder to stop the die holder from turning.

Not sure I like that idea much.....Dockrat make a new one! And don't make it out of Brass.

Westline
10-19-2011, 07:54 PM
Now I have to figure out how to make the pin jump ahead when I reach depth so all I have to do is reverse the spindle so I won't have to crank the tailstock ahead to pick up the pin again.

I have draw a few ways to do it but they are quite complicated.

Anyone got any ideas how to make it so you only have to reverse the spindle.


How about just adding a second pin without a screw lock on it you can just slide in by hand to catch the stop on the head for reversing.
You just have to drill a extra hole in the collar and make a close fitting pin.

Westline

Black Forest
10-20-2011, 01:00 AM
I had thought of adding a second spring loaded pin that is held back by the end of the block on the die holder. Then I realized that I don't need to spring load the second pin. It just needs to be far enough away from the first pin so I can set it to a longer length than the pin that stops the die holder from spinning. Then all I have to do is reverse the spindle and it will pick up the second pin on the way backwards. That will make it simple to adust for the length of threads.


Great minds think alike. Westline good idea!

Black Forest
10-20-2011, 06:27 AM
You all thought if you broke my camcorder you would be spared looking at my video's!!!! Now you have to look at lesser quality video's taken with my cell phone!

Here is the new improved version of the releasing die holder. The solution was quite simple. Just add another pin and have it stick out longer that the depth pin.

http://i853.photobucket.com/albums/ab91/burnandreturn/th_Video-0002.jpg (http://s853.photobucket.com/albums/ab91/burnandreturn/?action=view&current=Video-0002.mp4)

Westline
10-20-2011, 08:09 AM
Ok that settles it your a German import, I have been to Germany and none of them works this fast.
Good job I will be copying that..
Makes my 4 hour attempt to retread a roller this morning make me seem like a snail machinst.
Again great job.

Westline

Sorry for the edit my iphone suffers from early post syndrome.

rowbare
10-20-2011, 08:44 AM
That will work as long as you don't get distracted at the wrong time. Otherwise you will tap to the length of the second pin.

bob

Black Forest
10-20-2011, 08:49 AM
I don't know about anyone else but I pay pretty close attention when I have the chuck turning! Not different than turning to a shoulder.

techonehundred
10-20-2011, 10:26 AM
That looks really good, the only thing I can see is that you only have about 3/4 turn to get the spindle stopped before it catches on the return pin. One thought that I had was to mount a return pin on the die holder that has a screw in the middle and spring loaded so that it will rotate swing away and allow the catch to pass when it is threading and the lathe is moving forward and then a stop so that it will catch and reverse off the die when the lathe is moving in reverse. Another words, a form of a ratchet.

Black Forest
10-20-2011, 12:57 PM
That is a good idea with the second pin mounted on the die holder.

If you watch the video again I stopped and reversed the spindle in under 1/4 turn. It is only a matter of how fast you want to thread. I think at 40 or 50 rpm it is no problem with my particular lathe. It will reverse practically instantly at low rpm's.

J Tiers
10-20-2011, 07:49 PM
Yeah..... you want to make the reversal right sharpish if you use that system.

The original book one had a pin and catch arrangement that didn't engage unless you retracted the holder a bit.

So you advanced the holder, let it tap to depth, then after it was "free", you reversed the spindle and pulled the holder BACK a bit to engage the "reverse-out" mechanism and un-thread the tap.

I don't like the automatic catch mostly because I use the holder to speed up threading.... so I don't want to go slow. The original was for screw machines, and would have been set to run rather fast, probably, since cycle time is money on those machines.

Black Forest
10-21-2011, 12:18 AM
How fast do you either tap or use a die to cut threads?

J Tiers
10-21-2011, 08:45 AM
I don't have speed calibrations on the machine, but I'd reckon at least three or 4 times faster than what I saw on the video.

Rustybolt
10-21-2011, 09:35 AM
http://www.brown-sharpe.com/60.php

There's a drawing of a B&S acorn die holder. The principle is the same.
If I remember correctly on a screw machine reverse was twice the speed of the feed.

Black Forest
10-21-2011, 09:51 AM
I did a quick drawing to get an idea of how to build the stop so it would not be so critical to get it stopped before one full revolution happened.

Basically for you old farts that are too slow to reverse in time!

Esentially the bronze collored leg moves out of the way everytime the die holder rotates. As the die holder gets pulled off the pin and starts to spin with the spindle the leg is pushed out of the way for every revolution. When the spindle is reversed the leg comes up against the block and the die holder reverses. Of course the bronze colored leg is spring loaded. The blue pin is stationary but adjustable in length to allow the desired length of thread cut.

http://i853.photobucket.com/albums/ab91/burnandreturn/jpg.jpg

Black Forest
10-21-2011, 12:54 PM
I tried it today running at 100 rpm. Was no problem to thead at that speed.

dockrat
10-21-2011, 01:54 PM
BF, Don't bother me, I'm polishing brass :D But now that you have my attention, you have one more step to go. You need to make it capable to hold both round dies and hex chaser dies.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1580Medium.jpg

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1581Medium.jpg

Black Forest
10-21-2011, 02:08 PM
That is ugly!

I don't have any hex dies. Tomorrow I will make different size die holders to go in the end of what I have. Right now I can only thread with 45mm diameter dies.

Throw that brass crap out and use steel. Be a real man!