Elevating boring table for lathe cross slide.

[Dennis PatakiParticipant @dennispataki22631]

Often enough I use my lathe like a horizontal boring machine. I have a swiveling table I mount to the cross slide, and the piece part is bolted to it

The problem is getting the part set to the correct height. I mess about with shims and spacers, but its a painful and time consuming procedure.

Does anyone know about an elevating boring table that I could mount to my cross slide, secure the piece part to, and then quickly adjust for the correct height?

Such a device would be a real solution to this problem.

[Dennis PatakiParticipant @dennispataki22631]

[GavlarParticipant @gavlar]

A miiling slide?

 

 

 

 

Edited By Gavlar on 06/12/2022 21:45:36

Edited By Gavlar on 06/12/2022 21:46:21

[BazParticipant @baz89810]

I use a vertical slide set parallel to the lathe axis.

[Clive FosterParticipant @clivefoster55965]

Found a reference to an elevating boring table design by Woodson published in PM sometime in 1941. As the reference is Americentric I presume PM refers to Popular Mechanics magazine.

Popular Mechanics can be found for free download in pdf format and on Google books. Depending on your patience and Google-Fu it should be findable.

Clive

[IanTParticipant @iant]

There was a design in ME (or MEW?) where the work was mounted on a hinged work table and the work height adjusted by changing the table's angle. Sorry cannot recall the detail at the moment. But the slide sounds the easiest route if you have a rigid one.

Just a personal preference but I've never been keen on the all swinging and singing Myford type slides. I have a heavy Chinese one which is very solid but it only mounts face-on or parallel to the axis which is all I need.

Regards,

IanT

[peak4Participant @peak4]

I guess it depends on how much headroom you need and the centre height of your lathe.
I have one of these, which might do the job if you have sufficient space; I've not tried it for that purpose though..
https://www.arceurotrade.co.uk/Catalogue/Workholding/Work-Tables/Angled-Work-Table

Bill

[Clive FosterParticipant @clivefoster55965]

Arranging calibrated pure vertical rise and fall from below, rather than via an off set slide running in dovetails, without inducing tilt errors is tricky. Several styles of lab jacks are made that might, potentially, work for you and could be taken as design inspiration.

Commercial double parallelogram style platform lab jacks are generally specified for better than 10 thou per foot tilt. Typically being rather better. Impossibly expensive though. I'd expect a carefully constructed home made version with solid, hing style, pivots running straight across rather than the common commercial 4 arms each end style to do rather better. Lots of work to make.

For small work a large diameter mating pair of threaded cylinders in the centre can work well but getting at things to adjust can be tricky and preventing rotation when screwing up or down needs accurate guides. Travel is inherently limited. Way down the "lab jacks I like to use" list.

A micrometer driven sliding wedge device can give you perhaps 1/2 " / 10 mm of accurate shake and tilt free travel. Inherently bulky, at least 2 inch cube compressed, and more careful work than you might expect to make it. But it is accurate and stable. The lab jacks made in this style by MicroControle were essentially tilt free to interferometric standards. Seriously expensive, hundreds of £ back in the early 1980's.

Objectively lifting from below isn't a practical proposition.

Clive

[Joseph Noci 1Participant @josephnoci1]

Posted by Clive Foster on 06/12/2022 23:24:41:

Found a reference to an elevating boring table design by Woodson published in PM sometime in 1941. As the reference is Americentric I presume PM refers to Popular Mechanics magazine.

Popular Mechanics can be found for free download in pdf format and on Google books. Depending on your patience and Google-Fu it should be findable.

Clive

Referenced in HMEM forums as well

PM Boring table

PM archive here – looked at all 12 -1941 issues and did not find the table….Fun reading though, although PM seemed to be rather War oriented back then…

PM Archive

Maybe MichaelG will find it for us – I am also interested.

[Michael GilliganParticipant @michaelgilligan61133]

I presume post #16 here : **LINK**

https://www.homemodelenginemachinist.com/threads/lathe-boring-tables.1282/

to be the starting-point for that quest

[ and I haven’t even had coffee yet ]

MichaelG.

.

EDIT : may I have breakfast now, please ?
 

https://www.yumpu.com/en/document/view/11358918/boring-and-milling-table-home-model-engine-machinist

Edited By Michael Gilligan on 07/12/2022 07:08:32

[JasonBModerator @jasonb]

The problem with any elevating table is it will rapidly eat up the height between cross slide and lathe ctr line so you won't get the work in.

Packing and shimming should not be long an painfull. Establish the exact ctr height of your spindle above the cross slide. Then it's just a bit of maths to work out how high any packing needs to be, so make that up with parallels finally tuned with a couple of feeler gauges.

Clamp the work to the cross slide rather than loose rigidity using a vertical slide and you can usually mount larger work to cross slide that than you could a vertical slide.

 

Edited By JasonB on 07/12/2022 07:31:37

[Michael GilliganParticipant @michaelgilligan61133]

See my previous post:

Hard copy of magazine is on ebay: **LINK**

https://www.ebay.com/itm/194432948884

Listing includes a photo of the contents page.

Q.E.D.

MichaelG.

[JasonBModerator @jasonb]

The myford that the OP has already has the "starting point" as it has a slotted cross slide which is what that thread was about.

If you put say a 1" thick sub-table onto the Myford and then add some way to elevate it and a way to bolt it to the existiing cross slide you sill soon run out of usable height.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by JasonB on 07/12/2022 07:25:12:

The myford that the OP has already has the "starting point" as it has a slotted cross slide which is what that thread was about.

[…]

.

True … but it’s not what the Woodson article was about

MichaelG.

.

Edited By Michael Gilligan on 07/12/2022 07:36:19

[Alan JacksonParticipant @alanjackson47790]

This will do all you require

http://www.lathes.co.uk/stepperhead/

Alan

Edited By Alan Jackson on 07/12/2022 10:09:36

[Clive FosterParticipant @clivefoster55965]

Agree with Jason that packing and shimming for a "one set-up" job needn't be a major pain.

If thats the way you need to work best to get yourself properly organised with a drilled and tapped sub table and a nice stack of calibrated spacers and shims so you can easily build up to the right height. The packs of colour coded plastic shim sheets are great for the final, fine setting, bit.

Most of us have a blind spot when it comes to getting organised at the shimming and packing side of things. We'd far rather do the sort'n swear search though all the odd bit trying to find something that will work rather than spend time equivalent to a couple or three search settings figuring out what a comprehensive set covering everything needs to be. Then finding what you have before buying what you need. Not forgetting a box to keep it in with a nice label describing the contents along with the will-power not to use the bits for something else!

Straight from the "Do as I say, Not do as I do." handbook. I don't want to consider how much valuable hobby time I've wasted over the years on such search missions. Probably months. But have I learned. Nope!

Much harder if you have to adjust the height without disturbing settings. I imagine a sub-table with four stout pillars beneath running in sufficiently long close fitting guides so it can be slid up and down without loosing registration could be engineered. Either rough lift (screws) and change shims before clamping back down or a pair of micrometer driven sliding wedges. Possible, almost certainly inelegant and will consume more space than you'd like. Considerable work too as it has to be right. I suspect plain wedges would bind, MicroControle used needle rollers between the wedges on their optical lab device. One reason for the heart attack price.

Big thank you to Micheal for finding that elevating table design.

Clive

[HopperParticipant @hopper]

What's wrong with using a Myford vertical milling slide? It is designed for doing exactly what you want to do. You can measure the elevation to the nearest thou with a turn of the handle and its graduated collar.

Get the fixed vertical slide, as it is much more rigid than the double-swivel type. The fixed slide can be pivoted in one direction by the way you mount it on the cross slide so there is still that versatility.

You can clamp the job directly to the T slots on the vertical slide, or hold small jobs in the Myford vice made for the job.

 

 

 

Edited By Hopper on 07/12/2022 12:18:22

Edited By Hopper on 07/12/2022 12:24:23

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Hopper on 07/12/2022 12:17:19:

What's wrong with using a Myford vertical milling slide? It is designed for doing exactly what you want to do. You can measure the elevation to the nearest thou with a turn of the handle and its graduated collar.

Get the fixed vertical slide, as it is much more rigid than the double-swivel type. The fixed slide can be pivoted in one direction by the way you mount it on the cross slide so there is still that versatility.

[…]

.

Not knowing exactly what Dennis wants to do … I can’t presume to answer on his behalf

[quote] Does anyone know about an elevating boring table that I could mount to my cross slide, secure the piece part to, and then quickly adjust for the correct height? [/quote]

But Mr Woodson’s device [even scaled-down] would perhaps handle bigger workpieces than the Myford vertical slide.

MichaelG.

[Dennis PatakiParticipant @dennispataki22631]

Thank you all for your replies.

My lathe is a 6" CL height (12" swing) Atlas Craftsman. My T slotted cross slide is home made, measures 4" wide X 12" long, surface ground to .900" thick, made from 1020 Hrs. It really works a treat. I've been using it almost daily for at least 30 years.

The operation I am doing is boring and tapping the side of a pump housing for either 1/2 or 3/4" pipe threads. I have an Atlas vertical slide and a home made 4 X 7" boring table for it, but using a vertical slide for this operation won't work; no surface to mount that is 90* to my tapped hole, and more importantly, not enough rigidity.

I scrolled through the posts, and haven't yet found the Woodson article in Popular Science magazine. I am sure with more effort I will find it.

So far, I think the tilting angle plate will be the best solution, unless the Woodson article has ideas I haven't considered.

Thanks again to all who replied.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Dennis Pataki on 07/12/2022 20:56:47:

[…]

I scrolled through the posts, and haven't yet found the Woodson article in Popular Science magazine. I am sure with more effort I will find it.

[…]

The link I provided has viewable pages of the entire article

… no need to register or sign-in

MichaelG.

.

Once more … 

https://www.yumpu.com/en/document/view/11358918/boring-and-milling-table-home-model-engine-machinist

Edited By Michael Gilligan on 07/12/2022 21:10:39

[Michael GilliganParticipant @michaelgilligan61133]

The four screen-shots that I have just taken on the iPad would be plenty good enough to work from.

MichaelG.

[Clive FosterParticipant @clivefoster55965]

Agree with Michael that screen shots from his link would be good enough to work from.

There may well be stability issues due to overhang with a larger version sized for the 12" swing Atlas that Dennis has.

I'm tempted to use it as a starting point for one to fit my Pratt & Whitney Model B which is even bigger. if the customer job I'd need it for materialises I shall turn the design through 90° so the adjuster is at the front or back and arrange shim carrier supports onto the saddle wings. Rather than relying on the elevating screw and column for stability under load I shall drive it down onto shim-stacks to set the height and bolt it in place. The screw merely being a convenient way to lift the table for adjustments.

I shall be dealing with a 5 inch or so diameter hole with appropriately sized tooling so it's has to be stable. Hopefully the customer will be scared off by the quote but if he insists I want some nice tooling out of the deal as well as useful amounts of cash.

Clive

[HopperParticipant @hopper]

Yes it looks a bit unstable cantilevered out from the round column like that, rather like the table on a drill press. But some jacking screws at each corner could soon sort that.

[IanTParticipant @iant]

Not sure if this is useful to you (unless you know someone with a horizontal mill at your local ME society) but you can bore between centres on a Horizontal without too much effort.

Obviously you can use a boring head too but that might not have the reach required. I have a photo of this operation somewhere but can't put my hands on it at the moment. Needs a special 'centre' (or holder) made for the other end of the overarm and careful setting up. Not a proper Horizontal borer of course but usable for really large/awkward parts.

Regards,

IanT

[Clive FosterParticipant @clivefoster55965]

Picking up on Hoppers comment about screw jacks and running with it I wonder if having the boring table simply jacked up and down guided by stout columns attached to a fixed under plate might be a better way.

The 6" Atlas Craftsman Dennis uses has much more room above the cross slide than the usual run of Model Engineer home workshop lathes we are used to. Look at the lower pictures here to see :- **LINK**

http://www.lathes.co.uk/atlas/page4.html

It would seem feasible to attach a stout square or rectangular plate to the cross-slide with a cylindrical column at each corner with the boring table proper running up and down it. I guess something in the 1" to 1 1/2" diameter range would work for the columns. Maximum stability would need some sort of locking arrangement to securely lock the table to the columns after setting. Something a simple as a slot and pinch bolt in the side of a guide hole should do.

Simplest way to lift things would be a fine thread bolt close to each column. Turns counting would get you close to even adjustment. Add a hole for a depth micrometer, vernier or digital gauge to measure things would let you set each corner just so. It would seem best to have some way of locking the table down onto the jack before clamping up the pinch bots or whatever. Probably such provision is essential if downwards adjustment is to be reliable.

Plenty of ways to refine the idea or modify to suit components on hand and/or economical to purchase. Putting a fine thread on the guide columns with suitably calibrated lift nuts for direct setting sounds attractive. However such will be hard to engineer if absolutely positive setting is needed and clamping the boring table to the column after setting for maximum stability difficult.

In my working days I built a large system of this ilk using the Thor Labs 2" column / rod system and aluminium breadboards with simple screwed rods for jacks. The carriers riding on the column acted as guide bushes and, being something over 3" long, made the whole thing incredibly stable.

Clive

Edited By Clive Foster on 08/12/2022 13:52:08

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