Holbrook C10 Lathe

[Ueee]

Hi all,
Here are some pics of the lathe as she is.

The electrical problem turned out to be the electrician and not much else. The coil on one of the contacts went and it was replaced by a modern unit. However when the switch box was put back together the main contacts that control the motor speeds was put back in 180 deg out. By fluke it meant that the low speed contacts lined up but none of the rest, and somehow they did not short anything! Once i had worked out what was wrong it was as simple as pulling a split pin out, rotating the contacts around and putting the pin back in.

There are a few issues, the worst by far is the brake jams in the high speed position making it hard to get back to neutral, and the t/s handwheel has been replaced with a stop cock handle at some stage. What the? The T slots in the rear of the cross slide are broken out and the cross slide stops are missing too.

Anyway, she'll get a good clean at this stage. I think i'll need to get some positive rake carbide for her, not enough power or high enough feed rates for the negative rake WNMG's i've come to like. Fantastic finish of HSS though. When you can feed as slow as .0004" per rev you wouldn't expect anything else.

Cheers,
Ew

[welder]

looks like a great lathe there Ueee :oo::o:C

[Stustoys]

Another interesting machine for the collection Ewan.


When you can feed as slow as .0004" per rev you wouldn't expect anything else.
Always in a hurry. Still maybe thats why you get so much done :p


Stuart

[RayG]

Hi Ewan,

Nice acquisition, looks good.. I was going to make a comment about diminishing space, but then I looked in the workshop door here. I'm starting to keep an eye out on Gumtree for a used tardis.

Ray

PS... I'll be in your neighborhood next week... anything you need picked up?

[Techo1]

That brings back memories for me, I used to operate a larger version Holbrook in the TAA machine shop at Essendon Airport, I wish I had taken some pictures of it.

Ewan, does it have a taper turning attachment?

Lex.

[Ueee]

Thanks guys,
The earlier holbrooks all came with a TTA standard, this one is capable of turning 12" length up to a 4" taper on diameter. It is mounted on its own t slot machined into the back of the bed, so it can be moved to any part of the bed or out of the way behind the head. Since the cross slide is a double slide there is no telescopic lead screw, you simple remove the tapered locking pin from the bottom section of the slide and drop it into the TTA slide. This way you still have full use of the cross slide.

Some more investigating last night and i have found a few more interesting features, you can disengage the saddle handwheel for metric threading, so there is no chance of it collecting you whilst you go back and forwards. There are oil pumps on both the apron and QCGB that oil pretty much everything from the cross slides to the change gears and all the internals. It has a quick retract for the cross slide for threading. The one big lack is a reverse for the feed from the apron.

I still want to put the vfd on it, but would really like an analog tacho (yeah its anal i know). Short of making one from scratch i don't seem to be able to fine anything suitable. Any ideas?

Cheers,
Ew

[Anorak Bob]

I still want to put the vfd on it, but would really like an analog tacho (yeah its anal i know). Short of making one from scratch i don't seem to be able to fine anything suitable. Any ideas?

Cheers,
Ew


A few rpm too many but how about a Smith's tacho ? http://www.ebay.com/itm/BSA-TRIUMPH-NORTON-ROYAL-ENFIELD-SMITHS-CHRONOMETRIC-TACHOMETER-/221411469001

BT

[krisfarm]

Ueee,
Sure is a nice solid looking lathe. You might be able to pick up a mechanical tacho with a more appropriate range from a truck wrecker, old diesel ones had a good range for your lathe.
Bob

[eskimo]

looks like the goods eh?

pink is my colour choice...same as RC's..maybe bit more pink

[eskimo]

the modern contactor needs some adjustment...some degrees anticlockwise by the looks of it

[RayG]

Short of making one from scratch i don't seem to be able to fine anything suitable. Any ideas?


Yes... I think I might have just the thing.. I'll dig out some bits and pieces and see if it's what you are looking for..

Ray

[morrisman]

Hi

It's always an exciting and somewhat anxious event, going over a new toy and discovering what is broken or missing :C

Does it have a normal camlock spindle Ewan ? Mike

[Ueee]

Thanks Ray.

Mike, the nose is D1-4, taper I'm not sure on yet. They came with an mt2 sleeve originally but of course I don't have that. I do have a draw bar but no collets, plus the original copper tipped knock out bar.

Just like the poorly named 10EE the C10 will swing 12" over the bed.

Ew

[Steamwhisperer]

Hi Ewan,
fantastic pickup.
Now, let me see if I have this right.
The steam enters the drive mechanism through the steam valve where the tailstock quill used to be and that changes the spindle speed which will then...:doh:

Phil

[PDW]

Hi Ewan,
fantastic pickup.
Now, let me see if I have this right.
The steam enters the drive mechanism through the steam valve where the tailstock quill used to be and that changes the spindle speed which will then...:doh:

Phil

Come on, join the early 20th Century. The steam drives the Tesla turbine which drives the 3 speed newfangled Tesla motor which drives the 19th Century lathe body...

Those Holbrooks are very nice machines, let down IMO by an inadequate spindle bore. But then that's my opinion of my big Monarch, too.

PDW

[Ueee]

Well the lathe is almost back together. Just need to sort out the T/S handwheel, coolant plumbing and then think about the best way of wiring the VFD.

I made up 2 new wicks for the bearings, i bought some wool thread some time ago just for making wicks. Winding them was interesting to say the least, my first few attempts the wool just unwound from the wire once i was done. Phil T, do you have any info on winding wicks?

I have made a few cuts but really need some positive rake carbide. The finish off a shear tool is magical. It doesn't really lack the power to push the negative WMNG inserts but it does lack the feed speed. The highest feed in open gear is .00375" per rev. In back gear it will go to .030" per rev but only with a top speed of 250rpm. Lets face it, they were probably never made to remove lots of material.

I am missing a couple of taper pins, the graduations on the TTA should make it easy enough to get the angle right.

Cheers,
Ew

[Steamwhisperer]

Hi Ewan,
I certainly do. I am. Sure I posted it here somewhere but being out bush camping at the moment it might take me a while to find it. If not I will be home on Wednesday.

Phil

[Bryan]

This looks like a good start: http://www.woodworkforums.com/showthread.php?t=143904&p=1509662#post1509662

[Ueee]

Thanks Bryan, i thought Phil had posted about making them before but couldn't find anything searching for wicks. I had forgotten the term trimmings.

Ew

[Steamwhisperer]

Hi Bryan,
Thanks for that.
Post #321 is the one I was after in whisperings.

Phil

[Ueee]

Hi Bryan,
Thanks for that.
Post #321 is the one I was after in whisperings.

Phil

So to be clear, a wick like the image "D" on page 28, the wired section goes into the hole to be oiled, the "tail" on the right goes into the well and draws up the oil?

It may not look like it but the wells on the C10 are at least 3" deep!
Oops..i thought i had a pic of one, i don't!

Ew

[Steamwhisperer]

Hi Ewan,
You are correct. The tail hangs down into the reservoir. You can make them as long as you like.
The twisted wire part should stop just short of the shaft. This way you will make sure that oil will get in to the bearing and not around the outside.
The trimmings syphon as well as wick so the lower the twisted bit the better the oil delivery by syphon.
Hard to type on the phone so could possibly explain better after Wednesday.

Phil

[Ueee]

Thanks Phil.

I have hooked the vfd up and it is running ok I guess. I had to change a few things as the motor kept searching around but I seem to have that sorted. The biggest issue is the lack of torque at 100hz. At 90 I can drop the high speed clutch and the motor bogs down a little but not much. At 100hz it must drop to about 25% of its speed, even when the clutch is eased in as much as possible. The vfd is saying the 1.5kw motor is pulling just over 4kw when you engage the clutch..... Not sure where to go to now. The only option I can think of is to use the 3 motor speeds still plus the vfd. Or possibly the vfd is at the limits of what it can give the motor. I should hook a meter up and see what it draws without the vfd. I don't have a bigger 415v capable drive to try.

Ew

[texx]

a tractor wrecker that has a lot of very old tractors might be a good place to look for a tacho .

johno

[Ueee]

Thanks Johno.
The more i think about it the more making a digital analogue tacho looks good. That way the reading can be exponential so you can tell 30rpm from 20rpm but still go to 2000. The way the VFD went yesterday though I'm not even sure what to do next. I'm hoping i can catch up with Ray and see what his suggestions are.


https://www.youtube.com/watch?v=kaddlpsdBE4

Ew

[Steamwhisperer]

Hi Ewan,
is that a grease dab in the tailstock for applying grease to the dead centres?

Phil

[Ueee]

Hi Phil,
Sure is, I'm sure I missed more than just that little feature too!

Ew

[Steamwhisperer]

Hi Phil,
Sure is, I'm sure I missed more than just that little feature too!

Ew

Hmmm very classy lathe then.
Loved the video tour as well.

Phil

[Michael G]

is that a grease dab in the tailstock for applying grease to the dead centres?


Sure is

But hasn't everyone's lathe got one of those? (Mine has) :U

Michael

[morrisman]

Is your middle name Stirling Moss , the way you were flicking thru those gears , like driving a rally car

[Stustoys]

Hi Ewan,

Not exactly sure what motor/VSD you are using but why not use the three motor speeds?

Stuart

p.s. nvm I see now...... I'm working on something like that ATM. I think it can be made to work though slower than factory. depends how much trouble you want to go to.

[Steamwhisperer]

But hasn't everyone's lathe got one of those? (Mine has) :U

Michael

Hi Michael,
everytime I go out and look at my lathe now, it seems so inadequate lol.

Phil

[PDW]

Hi Michael,
everytime I go out and look at my lathe now, it seems so inadequate lol.

Phil

Never mind, you just go and pat the nice Colchester you've got at work and appreciate the quality of a real machine....

PDW

[Michael G]

Everytime I go out and look at my lathe now, it seems so inadequate lol.

Hmm. I see your problem. Here are some pictures. Perhaps you could print one out, tape it over your tailstock and pretend... :U

311506 311507 311508

Michael
(sorry - couldn't resist)

[RayG]

I'm hoping i can catch up with Ray and see what his suggestions are.


Hi Ew, The trip up your way is next week, probably Tuesday.... I have a circuit board that has provision for a tacho that I'll bring up and you can see if it will work on the lathe.

I started on this a few years back and it got shelved for other projects, but seems like a good time to roll it out... I like 270 degree analog displays for tacho's

http://www.backsaw.net/pics/cnc/DSCN1653.JPG

The lcd and the 4 pots on the upper right are for a ( yet to completed ) feed and speed calculator, that eventually would feed the speed reference to the vfd..

Ray

[jhovel]

Hi Ray,
when you eventually finish the calculator part of it and the control for the VFD, can you consider coding for a lathe option? One that would allow entering a starting and finishing diameter and vary the spindle speed to maintain the set surface speed? I'm not quite sure how you could feed in the current diameter along the way, mind you, but I can't imagine that to be a big hurdle for you :U
Maybe an input from the DRO scale?

On my lathe - with soon-to-be fitted stepper drive to the y-axis (as well as lead screw), the controller might tell your processor where the cutting tool is.....
Now that would be something really interesting!

[Ueee]

Hmm. I see your problem. Here are some pictures. Perhaps you could print one out, tape it over your tailstock and pretend... :U

311506 311507 311508

Michael
(sorry - couldn't resist)


You call that a dab? THIS is a dab! I hope that little thing doesn't make your lathe feel inadequate.....

[Ueee]

I made up a 1/2" tapered mandrel today so i could true up the T/S handwheel bush and fit it to another handwheel i happened to have.

311531311532311533

I also took a few cuts on some some unknown 40mm bar as well, not a bad finish from a standard CCMT insert.....:D

311530

Thanks for digging that out Ray, sure looks interesting.

Ew

[RayG]

Hi Ray,
when you eventually finish the calculator part of it and the control for the VFD, can you consider coding for a lathe option? One that would allow entering a starting and finishing diameter and vary the spindle speed to maintain the set surface speed? I'm not quite sure how you could feed in the current diameter along the way, mind you, but I can't imagine that to be a big hurdle for you :U
Maybe an input from the DRO scale?

On my lathe - with soon-to-be fitted stepper drive to the y-axis (as well as lead screw), the controller might tell your processor where the cutting tool is.....
Now that would be something really interesting!

Hi Joe,

That pcb was designed to be part of the cnc conversion, the vfd reference switching is auto-off-manual.. in the manual position the vfd reference comes from the pot, while in the auto position the vfd reference comes from an external source, so a seperate processor could be used to change the spindle speed with diameter. At some point in that upgrade process, it becomes a cnc conversion..

Ray

PS... Ewan, do you want me to bring some hi-rake CC inserts?

[Ueee]

PS... Ewan, do you want me to bring some hi-rake CC inserts?

That would be much appreciated. I was tossing up whether to get some or some cermets. It would be nice to try a CCGT just to see how they go. There are far to many insert choices out there, the ones i have are Iscar CCMT09T04-14 http://www.iscar.com/eCatalog/Family.aspx?fnum=35&mapp=IS&app=20&GFSTYP=M

Ew

[Steamwhisperer]

Hmm. I see your problem. Here are some pictures. Perhaps you could print one out, tape it over your tailstock and pretend... :U

311506 311507 311508

Michael
(sorry - couldn't resist)


You call that a dab? THIS is a dab! I hope that little thing doesn't make your lathe feel inadequate.....

Couldn't resist! pffft, you guys couldn't wait. :D
I may just have to go out to the shed today and drill a hole in my tailstock then machine up a dab and never use it. :oo:

Phil

[harty69]

Nice one Ueee

welcome to the holbrook club

cheers
Harty

[Ueee]

Thanks Harty. Seems like a nice little club to be in:U

I spent the day re-wiring the switch board with new Telemecanique contactors. The main power contactor had already been replaced (that was the crooked one Eskimo pointed out) and the insulation on the coil was gone on the coolant one. The fwd/rev ones were ok, if a bit noisy but i figured since i had some new ones i may as well use them. The problem with the old coils is they double as the transformer for the display lights. Not something that is an off the shelf part unfortunately.....

Anyone after getting the board out i pulled off what i didn't need, re wired what i needed to and added some DIN rail for mounting the contactors on. After testing I put it back in tonight and it all works except the coolant pump is running all the time. I *think* i know why but i ran out of time his evening.

I am just waiting on an interlock to arrive, and i have left the old thermal overload unit in as i don't have a new one.

Damn its easy when you have a wiring diagram...(sorry Stu:q)

Ew

[thorens]

Thanks Harty. Seems like a nice little club to be in:U

I spent the day re-wiring the switch board with new Telemecanique contactors. The main power contactor had already been replaced (that was the crooked one Eskimo pointed out) and the insulation on the coil was gone on the coolant one. The fwd/rev ones were ok, if a bit noisy but i figured since i had some new ones i may as well use them. The problem with the old coils is they double as the transformer for the display lights. Not something that is an off the shelf part unfortunately.....

Anyone after getting the board out i pulled off what i didn't need, re wired what i needed to and added some DIN rail for mounting the contactors on. After testing I put it back in tonight and it all works except the coolant pump is running all the time. I *think* i know why but i ran out of time his evening.

I am just waiting on an interlock to arrive, and i have left the old thermal overload unit in as i don't have a new one.

Damn its easy when you have a wiring diagram...(sorry Stu:q)

Ew


you done a good job there Ewan , with all one color wiring like that is hard to work with even for electrician
Peter

[Ueee]

One of the worst faults is that you can't get a 5 cent piece to fall over when taking a cut (I think that's about 500rpm).


313575

How are you going to use it to shake the bubbles out of two pack mixes if it doesn't vibrate?


I just couldn't resist.....
313772
2000 RPM .010" DOC. Actually the hardest part was finding a 5c piece that would stand on its edge full stop. Presumably once they have been in circulation for a while the edges get knocked around and start to round over.

The problem with the coolant pump wiring was as i thought and it is working as it should now. Now i just need to get the coolant plumbing sorted and make some adjustable feet and level her. Mind you just sitting on the floor she is cutting a taper of only .004mm over 100mm.

Ew

[harty69]

I just couldn't resist.....
313772
2000 RPM .010" DOC. Actually the hardest part was finding a 5c piece that would stand on its edge full stop. Presumably once they have been in circulation for a while the edges get knocked around and start to round over.


me either
313784
and its a holbrook so i dont think ueee will mind me posting this here
1000rpm .100 DOC and yes their hard to get to stand up in the first place

cheers
Harty

[Bryan]

Harty if you have yours running why haven't we heard about it? Start a thread or at least an entry in 'show us your lathe'?

[RayG]

I just couldn't resist.....
313772
2000 RPM .010" DOC.

Ew

Nice... I tried to stand a coffee cup on the CQ6250.... it rattled off the headstock almost straight away.. :)

Ray