Member postings for Clive Foster

Regrettably specification measurements aren't accurate enough to ensure proper functioning.

The fit needs to be very good and tolerances well controlled if the toolholder is to be stable when cutting. Those piston type posts work by pushing the holder outwards so that the two dovetails mate tightly. There is no inherently positve retention against angular tilt. They rely on the friction between the dovetails generated by the piston pushing outwards to stop the holder tilting and the tool tip moving up and down when in cut. The wider the tolerances the more likely you are to get a weak fit. Maker to maker variations are likely to be greater than tolerance banding from one maker.

That style of post is fundamentally weak when compared to something like a Dickson or Multifix which do pull into positive restraint in all planes. The Dickson design is inherently over-constrained with several different ways of getting a solid fit yet mixing and matching inexpensive versions is frequently unsuccessful. The piston types are under-constrained so even more likely to suffer from mix and match problems.

Clive

Mike

Colchester call the drive shaft a spline shaft so its possible that the pinion was driven via a "single tooth spline" broached into the bore to stand proud of the support bushes. Easier to assemble than a loose key but vulnerable to shearing off causing loss of drive.

Clive

Edited By Clive Foster on 21/12/2022 17:08:56

The simple centre square **LINK**

https://www.toolbank.com/0/p/FAICSQUARE38

pre-dates the combination square with V stock like that linked to by Duncan. I imagine that would have been a common way for craftsmen to locate teh centre of a round bar for puching to make a drill starter hole. Back in the day a combination square set would have been seriously expensive. Few ordinary workers could have afforded their own.

I've had mine for 50 years and use it so rarely I've almost forgotten I have it. More likely to grab the Starrett combination set I scrimped & scraped up the price for second and 40 odd years back.

Clive

Russ

Looks as if the simpler circuit diagram of the pair I have is the one for your machine. If its not exactly right it will be very similar.

PM me and I'll send the pdf file over.

Clive

John

Regrettably that diagram is for one of the American DC motor power feed units. Goes with a 6F or 8F system. Seem to be several variants on American machines, most with reliability issues.

Clive

Russ

I have a PDF of one for a machine fitted with a motor and gearbox type power feed that is in two sections. One is essentially similar to the later machines with a big, multi-tap transformer. The other is much simpler version showing a transformer with 6 v output for an optical measurement system and taps for the common work light voltages.

The parts list states transformers provided to customer order. So far as I can see the transformer in the simpler circuit is a simple add on. All the control gear being directly run from the incoming 3 phase, with, apparently, simpler interconnection.

Cleaned up from a scan of a very ratty and foxed n'th generation photo-copy around 30 years ago to help sort a friends Bridgeport. I can't be sure the drawing of the simpler circuit is correct because his had the later style of transformer. Looks OK but .....

If it sounds useful PM me with your E-Mail and I'll shoot it over. Seriously weird colour so lord knows what will happen it you try to print it! Original was cleaned up in MacDraw and its gone through two or three other programs before being PDF'd.

Clives

I like the "optical" type of centre height gauge comprising a sheet of decently thick perspex held vertically up right on a suitable base able to sit on the lathe bed and, if the top is flat, cross-slide.

Using a sharp centre lines can be scribed on both sides directly on the machine so they must be accurate. Needs a bit of thought to arrange a stepped down bridge across the centre of the bed to slide the base on for marking but its not intrinsically difficult. Keep the bridge because its useful for getting the gauge into more places.

With lines bot side of the transparent sheet you can reliably eye up the tool centre height from all sorts of distances. So long as you only see one line you must be looking at it level. Out of level wyou will see two. So if the tool tip alings with one visble line it must be on center.

Sitting a mirror behind at 45° allows you to look down rather than across. Or just use it as a plain line gauge by touching the tip of the tool (gently!) to one side.

A desigg was published in the early days of MEW. I modified it to suit my machine. Mine has grown several sets of lines to suit two machines but it works very well. Blade is thinner than ideal at 5mm, 10 would have been better, but I used what I had. If I ever luck into a suitable off cut of 10 mm perspex sheet I shall rebuild it.

Mine with mirror.

Using the mirror.

On the S&B 1024.

I really should do some better pictures but its hard to photograph transparent things.

If I still used a 4 way tollpost with shims to set tool height something like the dial gauge arrangement Douglas uses would be great. Measure the the height with no shims in and select from your carefully sorted set. No reaon you couldn't do the measurements on the bench using a bare tool.

Clive

The issue with improvised systems will be stability.

The proper thing is made as several sections to help control wobbling around as it goes up. Presumably there is something clever inside the bags to justify the outrageous price.

The big car jack bags are seriously squidgy in all directions. They rely on the weight of the car and grip of the un-lifted wheels to stop them flexing their way out.

For people lifting I'd be much happier with the airbag in some sort of parallelogram style frame with a seat on top so the airbag just lifts. The frame gives stability.

Clive

Richard

This is how the factory did the limit switch to stop the direct drive, clutchless, versions of the machine at the end or the cut.

Basically an industrial microswitch unit fixed to the main frame with a carrier for the actuating bolt on the pivoting pin the bow and slides ride on. Bolt sits as close to the full radius of the pin as it can. Probably better to fix a longer bracket across the pin so the bolt moves on a bigger arc. Mine is a bit sensitive when it comes to adjustment. Difference between stopping before cutting off and never stoping at all is a very small fraction of a bolt turn. 1/4 BSF thread on mine I think.

Picture is a bit murky 'cos everthing is the same blue-grey oily colour but you should get the idea. Saw bow in parked raised position.

Clive

Edited By Clive Foster on 13/12/2022 16:48:50

+1 for the Brooks design suggested by Brian.

After long consideration it was the one I decided to build but a Clarkson tuned up local at a price it would have been rude to refuse so it never happened.

Incidentally the first few years of MEW coincided with a bumper crop of home build sharpener / T&C grinder designs from various magazines and internet source. I hoovered up about 10 or 12 references around that period to choose from. Its been pretty quiet ever since. I guess the design seam has been pretty much worked out.

Clive

My experience is that sharp, really sharp, adequately solves 90% of drilling problems. Assuming decent quality drills to start with of course. Most of the economy ranges are really for hand drill and the rougher end of pillar drill jobs so wider tolerance bands are fine. You might get a nice one, you might not. Generally the expectation is that such will be broken or bent before blunt becomes an issue.Often the pretty TiN coated ones turn out to have only a thin crust of hard material under the make-up so sharpening isn't possible. Not necessarily a bad thing if the drill is also less brittle. I've seen such cheapies pushed so hard by big guy in a hurry that they are significantly bent and survive.

Even with a conventional point bumping a sharp drill into the work a few times will get you a clean start. But you will have to re-sharpen more often.

Given that both Andrew and I have Clarkson drill sharpeners its interesting to see how different our drill practices are.

Andrew finds that by the time his drills need sharpening they are often in poor enough overall shape that new replacements are appropriate.

Given that the default state of my Clarkson T&C grinder is with the drill sharpener set up any drill whose sharpness is even the slightest bit debatable gets mounted and restored to proper condition. As it's about a minute, on a slow day, between a beady eyed "Hmmn" on picking up the drill to putting something sharp enough to shave with into the machine chuck I see no reason to accept anything beyond the most minor wear. After 10, maybe 20 holes in steel you can feel that the drill has lost its best edge. Still perfectly good for, probably, 'undreds more holes but ....

Clive

Michael

Ordinary cheap diamond dresser about 6" long from one of the usual ME suppliers. Long forgotten which one tho'.

Stout rod clamped in a three way pivoting vice does for a support. Vice similar size and layout to the official Clarkson one but much cheaper. As always in that era, 20 odd years ago, a bit of rework needed to get it just so but nothing major. Only thing I recall was having to re-eningeer around some cheap, nasty and ill installed roll pins. Possibly a 2' version of the Soba Universal, now £130 odd from Chronos, but badge and memory have long faded.

Clive

If you are stuck I can measure components off my "spare" saw that's been waiting for ages to be rebuilt.

That said later versions, like the one I use, are direct drive by two belts via countershaft to get the necessary speed reduction. Controls are a simple push button Direct on Line starter with an industrial rated microswitch in the coil circuit to turn it off at the end of the cut. Last of the older ones on open legs use the same saw bow assembly as the solid base type like the one I use so the castings have provision to operate the microswitch.

Never used one with the clutch mechanism but frankly I don't see any great need for it id the machine has its own motor rather than being driven by line-shaft. My spare was hooked up to a line-shaft running in a trough in the floor. But a late type self contained one turned up at a price too low to refuse about a week after picking the "spare" up.

Clive

Michael

Yes thats right. Angle the dresser so the point can't grab the wheel whatever happens it needs to be just spat or deflected away.

Light touch is the order of the day here.

Those are the only things that actually matter. Plenty of variations in technique to get the best results for a specific job but anything reasonably acceptable will work well enough for folk like us. Albeit more slowly than perfect expert technique. But isn't that always the way for everything.

Just don't burn the tool when grinding. Proof positive of too heavy a hand.

As colin said careful free hand dressing generally gives a more open wheel for tool sharpening. Which is why I normally dress free hand. But ultimately I'd trust my gentle hand grip over anything solid.

Clive

The important thing is that the dressing diamond point trails the wheel rotation and that it held lightly so that if something does go wrong the point is pushed away from the wheel rather than digging in which can fracture the wheel.

I've seen it said that mounting the dresser above centre-line can improve the point trailing geometry. Personally I think that niceties of technique don't make much difference for the ordinary parallel dressing I mostly do.

Generally Clarkson wheel guards are on the skimpy side so exploding wheels are very dangerous. Mine is the very early type with a simple bent steel strip. More likely to be hopeful than effective in a emergency. I scaled out and drew up diagrams for a reasonable replica of the latest type which made a nice ecercise in my teach yourself MIG welding course. If the welding had been cosmetically better I might well have written it up for MEW. Ugly maybe but plenty effective though.

T&C grinder wheels tend to be less robust that the grey wheels commonly found on bench griders which are designed in the expectation of being attacked with star wheel dressers. They are also specified to put up with agressive use by folk less than sympathetic to the stresses involved in heavy grinding.

Clive

Andrew

Figure 10 of the patent shows the device configured for ordinary straight slotting with a fixed tool held in a slotted, cylindrical, 'lantern" / "American" style tool post. The tool post also holds the two slides in alignment but has no provision to release the tool pressure on the return stroke, as a clapper box does, so the tool will drag on the return stroke.

Which will work but is not ideal.

As shown the arrangement also forces the tool tip to divine its support at rather greater distance from the holder than is the case with a Bridgeport E and similar clapper box equipped heads. Dealing with relatively long, somewhat slender tools is regrettably common when cutting keyways or splines in smaller bores so minimising tool length is a desirable attribute of a machine intended to regularly do such jobs.

Seems to me that, as designed and patented, the ability to do ordinary slotting is to meet an occasional need rather than regular work. So a relatively inexpensive but objectively imperfect design would be satisfactory. I'm a little surprised that an accessory clapper box type tool holder along the lines of the Bridgeport E head was not offered as an accessory for folk needing to regularily do internal slots. I guess it would have been too expensive for too small a market given that the machine is specifically aimed at the punch forming market where the need for ordinary slotting would be rare. The basic device is clearly going to be rather more expensive than an ordinary slotting head so getting one to do significant amounts of ordinary slotting work would not be economic.

Jan

If you contemplate doing ordinary internal slotting and vertical shaping up to a sharp shoulder I think it might well be worth the effort to make a clapper box style tool holder along the lines of that fitted to the Bridgeport E head. Not a vastly complex project. Basically an accurate U section base with a close fitted pin and inline tool holder held on by a shouldered bolt fitting the holes that lock the slides together.

I've found a few more references to show you the tooling a Bridgeport E uses.

Photos at the end of this thread :- **LINK**

https://www.practicalmachinist.com/forum/threads/bridgeport-shaping-attachment-tools.155587/

Catalogue picture of the Bridgeport set along with show off specimen jobs on page 8 here :- **LINK**

http://manuals.chudov.com/Bridgeport/attachments-cat-30.pdf

More pictures of Bridgeport tooling here :- **LINK**

https://www.hobby-machinist.com/threads/bridgeport-shaper-head-cutters-help-identifying.67069/

Just about possible to infer dimensions of the Bridgeport set from the drawings on this page :- **LINK**

http://manuals.chudov.com/Bridgeport/Shaper-Attachment/pg3.jpg

If you don't fancy doing a clapper box there is no reason why you couldn't make up a solid carrier extending down to the end of the ram drilled on the end to take that style of tool. Without a clapper box pivot the tools will drag on the return stroke and will quickly loose their sharp edge on harder material such as steel. On softer materials they are likely to pick up and adversely affect the finish.

But they will work.

Folk like us rarely need to do more than one or two slots at a time so even a short sharp edge lifetime should suffice.

Clive

Edited By Clive Foster on 10/12/2022 19:12:23

Jan

If you are using the radius capability you will need a short piece of tool steel held directly in the rotating shaft as shown in the patent drawings. I imagine the slot matches a (then?) standard imperial size so it can be relatively securely held by the grub screw.

For simple slotting I guess some sort of offset holder will be needed to put the holding shaft rotating axis in a similar position relative to the tool tip as the common clapper box system. On a normal shaper the clapper box pivot is significantly behind the tool tip position. Maybe up to a couple of inches on my Elliot 10M depending on tool size. I'm not familiar with vertical slotters but I imagine the geometry is similar.

Somewhere in one of my books there is a discussion of the engineering reasons for this arrangement.

The simple grub screw appears much less secure than the hefty bolt usually found on shaper tool posts.

I imagine tooling of similar shape to that used on the Bridgeport E head would be needed. As the E head is relatively common in home shop enviroments some information can be gleaned from the internet. Here are some nice pictures of the E head clearly showing how the clapper box is arranged **LINK**

https://www.ukworkshop.co.uk/threads/bridgeport-e-head-or-shaper-head-help.136483/

Its clear that the actual tool tip is offset relative to the clapper box pivot. I imagine that a dog leg tool holder could be made to replicate that geometry. Round shank with a flat on the tool to take a grub screw worked for Bridgeport so should be fine on yours. The real Victoria tooling is probably different but geometry must have been similar.

Clive

Andrew

I don't think that particular style of shaper / slotter would be very good at cutting internal keyways. The geometrical limitations of a rotating tool carrier rather than a clapper box would seem to seriously limit its useful stroke.

Jan

I had another go at reading the patent.

It seems that the important part about the radius cutting capability comes at the end of the (approximately) 200 word sentence describing claim 1 :-

"responsive to said continued movement of said driving member to rotate said tool holder in a direction forwardly and away from the workpiece to make an arcuate cut."

Translated into more normal English "the tool rotates away from the main, straight, cut as it comes to the end of the stroke."

Sharpening the tool is going to be tricky because, unless I've completely mis-construed the geometry, the tool is horizontal during the initial straight cut with the lower face leading. So the sharp edge is on the bottom. When the tool swings away from the straight cut there needs to be enough clearance behind the cutting edge to avoid the curved face being cut.

Essentially the same problem as getting enough bottom clearance on a boring tool in a small hole.

The result would seem to be, by shaper standards, a rather weak tool.

Clive

Edited By Clive Foster on 09/12/2022 22:58:33

Once you have translated the patent description of operation language, seems to be a rule that such descriptions shall be totally incomprehensible, its fairly obvious what's going on.

Designed for making punches comprising a stout shaped projection to make a hole extending from a larger parent bar.

When you have the thing set to slotting mode it runs as a normal slotter with the tool cutting on the downstroke and angling back on the upstroke to drag over the work without cutting. Just like a normal shaper.

Ordinarily shaper and slotting tools use a clapper box to permit this angle away from the work with a pivot a bit above the tool holder.

The device described in the patent appears to have the tool fixed in a simple rotating shaft running in trunnions. Which behaves in pretty much the same way as a clapper box when in slotting mode. Not the normal way of doing things as a clapper box has a much more advantageous distribution of forces enabling much heavier cuts to be taken.

The radius mode is especially suitable for making punches. It produces a curve blending the working part of the punch with the parent material. A sharp corner or roughly formed join is a stress raiser making the puch weaker and likely to break.

In radius mode the main part of the punch being made is cut using a straight downwards stroke, just as in slotting mode. The cam rotates the toolholder rotates during the last part of the stroke taking the tool away from the work leaving a radius at the end where the shaped punch joins the parent bar. Having the tool in a rotating shaft carried in trunnions lets the tool swing through 90° giving a clean radius between the punch and parent material. The actual radius being set by the projection of the tool tip relative to the centre of the trunnions in which the carrier shaft rotates.

The rotating shaft appears to take a standard piece of square tool steel. Lord knows what the thing you have is intended to do.

The diagrams in the patent are pretty good so it ought to be possible to figure out the relative orientations of parts.

The design isn't quite as clever as it seems because there are some severe restrictions on work size and shapes if the beast is to work as designed. In particular cuts have to be quite light or the tool will be forced out of cut. Significantly less versatile than the standard breed but what it does do it does well.

Clive

Edited By Clive Foster on 09/12/2022 20:00:00

It's a single phase motor with capacitor odds are its something wrong with the centrifugal starter winding switch gear inside or a wiring connection issue with the capacitor. If its fairly new the capacitor should be fine but sometime you do get infant mortality where one just dies at not very old.

Test is to get the spindle spinning and see if it picks up and goes when you hit start.

Sometimes its a contactor coil issue. Taking current but not enough to operate it. Not unknown when someone has done a three phase to single phase conversion on an old machine without noticing the contactor coil is 440 volts. Which shouldn't apply here unless someone has changed the contactor without checking coil voltages. I have seen one where the innards weren't lined up and there was enough mechanical ressistance to top the contactor working. Not quite tight enough screws let things shift over the years.

Clive

Edited By Clive Foster on 09/12/2022 12:45:47