Faulty boring head, help needed please

[Alan Waddington 2Participant @alanwaddington2]

Please bear with me, this might turn into a long winded post…………

A good while back i bought a Kuroda KKS UFB 3S auto boring and facing head via fleabay, have only just got around to having a play with it, and couldn't for the life of me work out how it was supposed to operate.

Watched a few videos of people using Wohlhaupters, which are very similar and began to smell a rat.

Anyhow, stripped the thing down this afternoon and I've definitely bought a 'wrong un'. It's been in bits before and bodged, with at least one part missing.

i suppose my first question to those in the know is, do we think it's fixable or have i bought an expensive paper weight.

The main problem is with the buttons that determine the feed rate 'B', the pawls which they operate 'C' and the cylindrical bearings that engage the drive 'A'

There should be two feed rate options selectable .008" or .004" when the appropriate button is pressed it shoves a pawl up inside the main shaft which in turn pushes the cylindrical bearing out of its hole, meshing with the drive ring.

In my example, at least one of the pawls .008" has been messed with by grinding/filing and the cylindrical bearing is missing, so no way is that going to work as is. The other pawl .004" looks unmolested and the drive bearing is present, however when i push/pull the button nothing happens, and looking at the shape of the button end and the pawl shape i can't see how it should/would work.

anyhow enough of my ramblings, a picture or three paint a thousand words.

[Alan Waddington 2Participant @alanwaddington2]

[Chris Evans 6Participant @chrisevans6]

A photo of the head before it was stripped down could be useful. It may be similar to my French made one (can't remember the make) I did strip it once when it malfunctioned but a long time ago as I have owned it for 30+ years.

[Raymond AndersonParticipant @raymondanderson34407]

Kuroda are still in business now called Kuroda Jenatec maybe best to contact them directly,. and hopefully they will be able to help.

[JohnFParticipant @johnf59703]

Alan, try this link they may be able to help

**LINK**

[John HinkleyParticipant @johnhinkley26699]

Alan,

I suppose you've seen this short video on YouTube? If not, it may help understand what the various knobs and twiddly bits are supposed to do. There's no voice-over but the slide movement is visible when viewed closely.

John

[BazyleParticipant @bazyle]

My guess is that the groove at the end of the button (UPA3-31) should engage a lever with the other end ditto for the second button so one going in pushes the other out though I can't see anything appropriate in the Wolhaupter part list. Maybe the owner had problems with assembly or dual engagement and made the modification/ left out one of the parts A.

Part A just looks like a slug of sliver steel.

[BazyleParticipant @bazyle]

Were the pushers C inserted the right way up? Do both sides operate if you use the good bits in each side in turn? Where do the grub screws in the photo fit? Are there wear marks on A or C? Is there an autostop on the other side of the head that pushes the button back out at the end of a cut?

Seems like quite a nice mechanism being continuous as some only advance the slide in jerks. You do need to ensure it is clean of swarf as It doesn't look like it has an overload escape in the design.

Re-reading your post. Does the end of the push rod align with the end of the button circular ring or with the double notch? The notch looks like a detent position but I'm assuming the push rod is supposed to ride up the side of it when you push it in. Then if you pulled it right out the push rod end might catch in the end groove so the original owner might have ground the end off to facilitate removal.

 

Edited By Bazyle on 22/08/2016 16:32:13

[Alan Waddington 2Participant @alanwaddington2]

Thanks for all the replies, much appreciated.

I managed to work out how the feed button mechanism is supposed to work, but elation was short lived…..stripped it down a little further and found one of the small gears is missing some teeth, guess it's had a major crash at some point interestingly enough both the larger ring gears it engages with look in perfect health.

Will try to follow up the kuroda avenue, and see if spares are still available, otherwise it's probably scrap

[BazyleParticipant @bazyle]

Scrap If you get to that point drop me a line.

[David Harris 8Participant @davidharris8]

Hi. Just signed up as I have the same model with the same problem also bought off the e bay. Found this old thread whilst searching for parts. Did you get yours fixed?

[Author]

Posts