Almost making a Wohlhaupter UPA-4 SK30 shank 

Thanks! I made it as short as possible. I’d like to have made the bar bigger but the spindle can only clamp 1/2” so that’s my limit there unfortunately

Yeah I made some assumptions and found out the hard way this time. Thanks for watching!

Yeah I have a different tool post on the compound slide. The multifix is mounted to a solid block that I can change out quickly in place of the compound.

I didn’t think to support the rim, thanks for the suggestion! When milling the slots I put the part on the side to have it contact the bottom of the vise, but if I put a parallel under it I could indeed clamp the part in the middle

Thanks Jason, I felt like I'd let others learn from my mistakes. Next one will be better for sure!

​@@ED_TMaybe add a radius where the taper meets the flange and add a radius where the taper turns into the round drawbar end, it will help againta cracking

No problem Jerry, I still haven't found a tougher insert. The workpiece was likely 55+ HRC when I used the inserts. When I re-make this adapter I'll machine it after it's tempered back significantly and more common inserts should work. That will also solve the distortion problem I had now

Glad you enjoyed the video!

I haven’t used it yet but I have no doubt

Me too man, me too

I don’t know if the differential screw is the same size for the larger boring heads, it might be larger. Drilling in the hardened shank might be possible but tapping it sounds like a lot of trouble. Good luck!

Thanks for the insight, the manual mentioned cutting tapers. In my case it’s a bridgeport with 3 feed selections. I’ll have a look what angles it can do with those

@@ED_T If your UPA4 has 4 possible feed rates (like mine has) then, combined with the 3 quill feed rates, that's 12 possible tapers. In an ideal world they would include 7/24, MT3, MT4 and 8 degrees for ER collets. But I bet they don't...

I believe the way it works on mine is that each one of the 12 buttons on the feed ring represent something like 0.02mm feed per revolution. So if all buttons were pressed the slide would advance 12 times 0.02mm per revolution. That would mean 12 different feed rates. I’m not 100% on what the feed rates of the auto quill feed has exactly but it would presumably be mixing metric and imperial feed rates which might result in some funny angles. Something else that might be interesting is to mount a stepper motor to the sensitive feed wheel of the quill with an encoder on the spindle, then the feedrate can be whatever you want and by extension whatever angle you want. Either way, I prefer doing tapers in the lathe where I can use my grinder which I can indicate.

@@ED_T On mine the buttons are in pairs (but are in the top face). They are actually linked by little gears, so pressing one pops up the partner. (mad!). So I have 8 buttons and 4 feed rates. What I have only just realised is that to turn off the feed you need to balance all the buttons in mid-position. If you fully depress all "leading" buttons is feeds one way, and if you fully depress all the "trailing" buttons it feeds the other way. So it is even more mad than I thought. Mine also has a rapid return screw, with a hex socket. In another fit of over-engineering there are three balls which release the lock on this screw automatically when you insert the hex key. It looks like you have the same lower section as mine, but the feed ring is different, so probably also have the tiny locking balls.

The wohlhaupter design was originally aimed at being used on lathe spindle to do boring mill work by placing the part on the cross slide with various mill table attachments that were popular back in the day, but you could probably use the sync taper on some gear feed drills too. Hence why they are so abundant with Morse taper shanks but rarely a stock steep taper

The 16mm reduction is part of an existing shank I was copying and it worked quite well as a relief area for the grinding wheel. Cones can be turned accurately but I prefer grinding them. If you look at commercial holders they are all ground, not turned. I will have to figure out something for tempering to be able to reach those temperatures somewhat consistently

@@ED_T I know that all the holders you can buy are ground, and if you have a good cylindrical grinding machine, it's also easier. We also had a Studer cylindrical grinding machine in my department, but we still turned hardened parts often enough. Very often with CBN inserts, which are very expensive. But of course the spindle bearing and the guides of the lathe have to be in good condition. At the moment I can't think of a device that can hold 500-600 degrees reasonably accurately for an hour. Apart from perhaps trying to maintain the temperature with a measuring device and the appropriate gas setting, or you could go to a small workshop that has a hardening oven. I would definitely avoid the sharp inner corners of the 17 mm diameter.

Are you talking Farenheight or Celcius ?

@@Andrew_Fernie Celsius

Yeah I've read the manual how to do angles with the Wohlhaupter but I'm not sure how well that will work in my Bridgeport. The Tree heads are really cool but whenever I need to mill a large taper I usually use the rotary table and tilt the milling head. Thanks for sharing your experience!

Such a bloody shame that draw thread piece broke off. After all that work, especially having to make the blank a second time. It would have been nice to see where the heat treatment distortion fouled it up, as you machined everything to size after heat treating it. That has me really confused. So next time a new oven to get the part up to temperature in a more even way, and would you consider making the oven an electric one? Also would an oil quench be better for less distortion purposes? Given the size of the piece of material those things need to be considered think. And of course if you are going to temper it this time an electric oven is far easier to control the way it heats to the max temp you want, AND let's the heat soak into the metal for as long as you want it to. Gas heating to my mind is just far too unpredictable. Good luck with the next attempt, and please bring us along for the ride again! Cheers from the UK

Hello Paul, thanks for your question! I've just checked in my drawer and I have a couple dozen different kinds of inserts that I've collected over the years. Some I use more than others of course but I can't break down all of them in a comment here unfortunately. In this video I've showed one with a very specific use case for hardened materials. Whenever there's something unconventional about tools that I use I try to remember to show it but that doesn't always happen. What I can tell you right now is that name brand inserts and holders are much better than the no name import stuff. Look up the feeds, speeds, depth of cut and application material for whatever insert you end up with and you should be good. Best regards from Belgium 🇧🇪

Hi thanks and great to hear back from you 🇦🇺🍻

I don't have the means of cementing steel myself at the moment

I just use basic stones meant for handheld die grinders, locally in the store I buy them for about 2-3 EUR per piece. They have a 6mm shank which I glued into an arbor with a larger diameter for better rigidity. It's very basic but it seems to work.

@@ED_T thx!

I don’t doubt that to be the case, but I can’t easily get my hands on any alloy I want since I’m not a business. As far as steels go I have easy access to mild steel, C45k and 42CrMo4. Other alloys would need to happen by chance. For next time I do want to build a small tempering oven first and temper the part before final machining. That way I can do the slots and holes after the warping too so they line up better.

Hello!

In short, English is not my first language and I’m much better at writing it than speaking it spontaneously. In the future I may start talking though, it depends on how I’m feeling

Yes 😁

In that system this steel would be 1.0503