Here is a list of all the postings Clive Foster has made in our forums. Click on a thread name to jump to the thread.
|Thread: Mystery Lathe tool, any ideas?|
Nooging around Google I found a suggestion that such chucks could be used on drill grinding machines. Sounds plausible as the long jaws should give a decent grip on the drill flutes without being so tight as to damage them. If its bored right through, like mine, and fitted to a hollow spindle there would be no problem in accommodating any drill that would fit. Even with a solid back the drill would need to be quite large before front stick out could become a problem.
Makes me wonder why the preferred form of drill holder for chuck equipped machines, Clarkson, Brierly, Dormer et al was the six jaw scroll type. Effective enough but always expensive.
Mine is generally similar but, I think, a little larger. Logo stamped on the side is a small crown so I guess it was made by Crown. Smaller front plate but same style of Veed jaws with angled grooves. Vee angle is 60 degrees so it holds hexagon and round stock. Whitworth form 6 tpi by 1 3/4" diameter thread approaching 2" long in the back for mounting. No register groove so probably doesn't fit a normal style lathe spindle.
Mine has a mostly hollow "tube bolt" with six external slots screwed into the mounting spindle having a square hole buried at the back. Best guess is 3/8" square. There is a short 1/2" spindle screwed into this mounting bolt which could be used to mount the thing in a drill chuck or collet. No way am I optimistic enough to risk that. This thing is a pretty serious lump.
Square at the back suggests that this could have been used as a tap driver but its very long way behind the jaws for a tap with that size of square. Would maybe need 4" or 5" of plain shaft. Vee angle suggests its made for hexagon stock but if thats the case I cant see any advantage over a normal three jaw. Probably less costly to make with simple screws instead of a scroll but still a proper job not corners cut for minimal price.
|Thread: Steel Machinists Tool Chest|
Big issue when choosing between so many look alike and very similar products is how to assess quality. The inexpensive ones can be fearfully cheap and flimsy. Can't go by price alone as their is a huge variation. Some of the inexpensive ones can be more than acceptable. Others so bad you'd almost have to pay someone to take them away. If you buy mail order you can't inspect them so about the only guide to sturdiness is the weight. I figure you need to be around 2/3 rds or upwards of the weight of the equivalent Snap On to be confident of something decently sturdy.
Doesn't strictly apply in this case as Richard F clearly wants it for small tools but the rated capacity of the drawers, and whole cabinet, from some suppliers can be fearfully small. In the absence of other information if a supplier also offers roll cabinets checking the quoted drawer loading may give an indication of the quality of the rest of the range. All sticker brands tho' which doesn't help. Before buying my used Snap On I looked at some of the stainless roll cabs, presumably similar to those Clogs is considering, and found one whose total rated capacity was rather less than one Snap On drawer. A 56" cabinet I think, memory says rated at about 20 lb per drawer, which would have got me nowhere.
Muzzers Homebase link shows two versions of the style in question. One at £63 and one at £146. The cheap one is about half the weight of the more expensive one. OK its a bit smaller but I'd expect the more expensive one to be significantly sturdier. To me a flimsy tool chest, along with drawers that don't open fully, is one of those fingernails on the blackboard things that would drive me nuts in short order. From what I've seen the £150 to maybe £220 price range is most likely to turn up something Mr Average Home Shop Guy would be happy with.
Ever since the import tool thing went mainstream its been nearly impossible to get a handle on the sensible quality / best price / best value thing. For example maybe a decade back I bought a toolchest of similar style to that under discussion containing a mostly decent set of mechanics tools from Halfords on special offer at essentially the same price as a significantly flimsier empty tool chest of similar size. Basically I swopped a set of tools for three small drawers. The basic Halfords empty tool-chest was definitely not up to standard but this one did me fine until I outgrew it and sold it on. The tool quality was a bit variable and the socket size selection more than a little odd but I still have most of the tools. OK some live in the loaner drawer. Saved me a ton of back'n forth from workshop to garage over the years. Something like this **LINK** but mine had an extra row of small drawers. Also, judging by the reviews, mine was much higher quality in both box and content. As I remember it sticker price was similar making real price maybe double so the stuff should have been better. Really its the sort of bargain you only find by chance and inspection. I just went in for a bottle of screen wash whilst HerLadyship was scoffing a burger at McDonalds next door.
Edited By Clive Foster on 25/03/2017 19:46:24
If the add on side cabinet I bought is typical the US Pro heavy duty range is a cut above Halfords / Machine Mart and not significantly more expensive. This is their version of the 9 drawer toolchest :- **LINK** . Dunno how it compares to Sealey which are similar price. My side chest is clearly not the equal of the 40" Snap On box it hangs on but its by no means out of place.
Richards link gives mostly Kennedy products which are close to real (not the lower end import versions) Snap On quality and getting on for similar price. Inappropriately costly new for Home Shop Guy but worth keeping an eye on E-Bay / Gumtree for good condition used.
|Thread: Air compressers|
Is there an automatic unloader valve fitted?
Some years ago I had an Atlas Copco KE2 Vee twin compressor with unloader valves in both cylinder heads fed by a spring loaded pressure release valve fitted to the tank. When the tank got up to pressure this valve would open feeding air to the unloader valves opening them so no pressure could build up in the cylinders. This set-up was intended to be used if you were using lots of air letting the compressor run continuously rather than lots of short start - stop cycles. Very important on a single phase motor as these can only cope with a limited number of start - stop cycles per hour without risking burning out the start winding. My valve was adjustable so you could set the operating pressure.
Had to clean up the valve innards a two or three times when contamination stopped it sealing properly. Air leakage was sufficient to open the unloaders before it got up to pressure. Small bleed hole in the system to let pressure out so the unloaders would close once tank pressure had dropped enough to close the main valve. This would block, or partially block, on a fairly regular basis driving the system nuts. I suspect my main valve never quite sealed properly so there was always a small leak through the system which probably didn't help.
On a small compressor the pressure release valve in the starter can leak enough to stop it coming up to pressure. In my experience this is only applies to compressors with less than 5 cu ft / min delivery.
|Thread: Tyzack hand pillar drill|
Is it the enclosed gearbox version or the exposed bevel gear version?
Exposed gear one has a bevel gear on the main drill shaft and two bevels on the handle drive, one large one small. There are two bearing holes for the handle spindle. Put the handle spindle in one hole to engage the large bevel with the gear on the shaft for high speed. Use the other one for low speed. Usually a a wire spting clip passing through a hole in the casting and engaging in a groove in the handle shaft to keep things in place.Not sure if Tyzack actually sold this type under their own name.
Enclosed gearbox type has two square shafts sticking out the side with fit the drive handle. One is high speed, top I think, the other is low speed. usually top one is high speed. Drill shaft is driven by a bevel. Low speed drives bevel direct from the handle, high speed via a step up gear train. There was a thread including pictures some time back.
These drills have an automatic screw feed driven by the inertial drag of the flywheel on top. If the thumb screw is close to the top its probably the drag adjuster which sets feed power. Cant remember whether more drag is for more or less feed.
Both types are same as equivalent "gut buster" large hand drill types. Probably used same components.
Edited By Clive Foster on 23/03/2017 08:48:56
|Thread: Twin start threads|
Did you make sure that the backlash was properly taken out of the system when switching things round. Seems to me that with such a fine thread it might be possible to have enough backlash in the gears to let you effectively reconnect one tooth out which would offset the second thread enough to leave a flat between the two starts.
Some years since I did one so no longer fully up to speed without the machine in front of me. usually my hands remember better than my brain for this sort of thing.
Think I'd go back to the pen with a bigger simulated workpiece and set a coarser thread then try the effect of deliberate errors. Like what a happens if I set up one tooth wrong. Maybe wrap a piece of paper round the inner cardboard tube left when the kitchen roll is used up for a simulated workpiece.
Yup. Its bringing thread dial rotation in that gets folk mixed up.
Rule for two starts is :-
180° rotation of the work without longitudinal shift of the tool tip along the bed
1/2 pitch longitudinal shift of the tool tip without rotating the workpiece.
Thread dial rotation actually measures longitudinal shift. Effectively the thread dial is a big, coarsely calibrated dial caliper. Need an absolutely clear understanding of that and how things tie together in practice if you want to use the thread dial to set multiple starts. Matin Cleeve goes into some detail on this concept in his book "Screwcutting in the Lathe". Sent me straight to the aspirin bottle! I mark the gears or chock the 4 jaw chuck as the effects of both are easily visualised.
Edited By Clive Foster on 20/03/2017 16:06:12
|Thread: Plastic for gears|
Tufnol is excellent if you use the right grade in the correct grain orientation. Allegedly stronger and better able to cope with shock loads than delrin or nylon. But ideally needs proper attention to lubrication for long life. Delrin and nylon are, up to a point, happy run dry if kept clean.
Chocolate fireguard time if you use wrong grade and / or wrong grain orientation with Tufnol.
|Thread: Balancing a pulley|
Seriously consider Micheal's suggestion changing over to poly-vee drive. Carving new poly-vee pulleys from solid isn't unreasonably difficult if you don't want to buy. Pulleys don't need to be very big. I had a Pollard Corona 100A drill, probably of similar size to your Jet, with 1 HP motor which used a poly Vee belt about 1/2" wide. Maybe 5 grooves on the pulleys. About something under 3" long overall for a 5 step stack. Worked very well. Poly-vee pulleys are easily made if you have an adjustable bed stop on the lathe or a fixed stop with a suitable set of different thickness blocks to step out the groove spacings.
I made one up step by step from a set of disks. Started with a solid bar a bit larger than the smallest pulley. Bored and keyed it to match the shaft. Made the smallest pulley first. Then turned the rest of the bar down to make a mandrel and pushed the disks on one at a time so I was always working on the largest disk. Fixed things together with loctite backed up by small counter sunk socked head screws. Each disk had 4 holes through it running parallel to the bore. Two clearance and countersunk for the screws. Two tapped for the screws holding the next disk.
Sounds like more work but its a defined job. I often find that starting over with something that can jus be made and will work is quicker than trying to sort a defective part or assembly.
Trying to fix an unbalanced, cast, multistep Vee pulley could turn out to be a truly miserable experience. The length means that not only do you have to deal with simple radial imbalance you may also have imbalance along the length of the pulley. Basic radial balance is relatively easily achieved by simple axle on a knife edge or free running bearings et al using the principle illustrated in Michael's posing tool link. But this may not be enough as there could still be compensating imbalances at opposite ends of the pulley so it will still vibrate. Not easily sorted even if you have the gear.
Way back I had to balance up some rotating devices of similar dimensions to your pulleys but less heavy that were intrinsically unbalanced in this manner. Had the use of a simple turbocharger rotor balancing machine with electronic readouts of imbalance but it still took ages and much verbal encouragement. As I recall matters the process was less than intuitive in that adjustments that seemed to be the right way to go about things didn't work out as expected.
Edited By Clive Foster on 20/03/2017 10:32:07
Edited By Clive Foster on 20/03/2017 10:35:13
Edited By Clive Foster on 20/03/2017 10:35:57
|Thread: Oscillating saws|
As another non woodworker except in extremis I entirely agree with how useful those saws are.
The Japanese style handsaws from Lidl are worth a punt too. Cut on the pull rather than push stroke and are very controllable for finer work. Razor sharp too.
Been putting off making some micrometer boxes for years but between those, the oscillating saw and the big Startrite bandsaw I indulged in a couple or three years back I might just get round to it.
|Thread: Induction motor vs older style?|
Induction motor is the older style, whether single or three phase. The real deal, if decently made capable of running for many years with minimal or no attention. Inherently single speed so needs belts, gears or other form of speed changing drive to cover a wide range of drill sizes. Belt or gear drive means proper step up in torque to cope with larger drills.
Non induction in this context usually means DC motor with electronic speed control to cover the needs of different drill sizes. Power drops off with revs so less ooph for bigger drills. Not good. In this context non-induction usually means inexpensive motor plus inexpensive electronics to meet the price demanded by the marketing guys. Chance of magic smoke escape after a relatively short life is high. Especially as the inherent lower power at lower revs makes it likely that the machine will be overloaded on a regular basis.
DC drives can be very good and very durable. But not at that price.
That SIP drill looks to have an induction motor on the back so probably a small three phase unit with inverter control. Price is just about high enough. With only a 550 W, 2/3 rds HP, motor will be decidedly wimpy on bigger drills.
Edited By Clive Foster on 12/03/2017 17:55:19
|Thread: Lathe line boring|
Tool size is an issue with between centres boring bar stiffness as the cut out for the tool clearly reduces stiffness. I've seen 10:1 plus tool diameter (assuming round tooling) quoted as a reasonable length diameter ratio for essentially zero deflection on our sizes of job. So 1 1/4 " bar for 5" deep hole with 1/4" tooling. As Neil says stiffness goes up rapidly with diameter so the formula fails when you get to big stuff like yours. Stiff enough is stiff enough 1 1/4 bar should be plenty for you. I've seen designs where the cutter mounting area has been enlarged to help ensure secure mounting and clamping of the cutter with the main bar being smaller to give a bit more room for measurement.
Cutter at an angle as per Geo. H Thomas makes setting easier and provides more support for the tool. If I ever need a big one I shall use thick wall tubing for the main bar with a lump fixed in the centre to hold the tool. Got a couple of foot of nice 1" diameter by 1/4" wall steel just right for the job in stock.
I have a long 1" diameter single ended boring bar and do need to start thinking about deflection beyond around 3 or 4 inches. Tool tip shape makes a big difference. Too much tip radius will increase push out forces considerably. Boring bar supported from both ends is effectively twice as stiff.
With a hole that size there is room to run the tailstock quill out a bit into the bore. So the bar can be less than double the bore length making the system stiffer. Puts cutter closer to the support too which also helps. Disadvantage of running the tailstock quill into the bore is less space to get the measuring gear in.
|Thread: Oxygen for Map gas|
You will need to change the regulator to match current readily avaliable small oxygen cylinders. Doesn't look much more to get a pair so you have the option of using small thread MAPP cylinders too should those be less costly. Of course with Rothenberg et al using CGA 600 form MAPP and other gases they are readily available. CGA 600 adapters all seem to be for fuel cylinders not oxygen.
|Thread: Editing posts after a certain time|
Idea is probably to ensure that relatively long delayed edits don't destroy the conversation flow of a thread. Editing really should be to cover the oops "can't spell", "incomprehensible phasing" or "finger trouble" issues. Real errors of fact, link or simple mis-understanding should be dealt with by a later posting recognising and correcting the error. Allowing much later edits could be considered as encouraging making yourself look clever with 20/20 hindsight.
Personally I don't see such as a problem. Folk here aren't that precious.
Hafta say I find it annoying to have spelling and finger trouble issues enshrined forever. Like starts for stops on a recent thread! Reckon there are more than a few folk who'd not mind excising a "humorous" comment that seemed OK at the time but embarrassingly less so a day or two later. Fair few instances where what would be fine spoken face to face comes over far too strongly in written form. Emotionally forums are close to mates chatting in the pub so its easy to overlook that its a written format whose style and content is best kept close to that of a letter. Whether formal or informal.
|Thread: Nut & Bolt Sizes.|
Time to upgrade your sorting strategy.
Start by downloading a copy of the (nearly) all threads in order of size listing originally due to Andy Pugh and further refined by Ian Wright and Micheal Jones.
A PDF version arranged to print out on A4 here **LINK**.
Then roughly sort into suitable piles over a range of sizes. Maybe really tiny, up to 1/4 - 6mm, then up to 1/2 - 12 mm and a final pile for bigger ones. Pick over the piles and group out "looks the same" by eye. Now you are ready to start measuring. Set your thread gauges with a suitable selection of leaves pointing out and have at it. Odds are your looks the same sorting will have been good enough that one measurement covers a whole bunch of bolts.
Nuts you have to sort by size over flats then try a fit.
Should be all over by Christmas!
|Thread: lathe identification|
Probably not. The Pittler seems to achieve everything with two rotational and one linear movement in additional to the usual along the bed shifts. Your ball turning tool approach would need to be top slide mounted and have two rotational and three linear movements as well as the along the bed shift. Once you start getting into asymmetric and ovoid shapes life becomes difficult without tilt. As I understand it the Pittler is inherently capable of producing such.
Need to consider the actual manufacture of the machine too. Accurate slides are harder than pivots. Especially in those days. So the Pittler way is less costly to make than Neil's equivalent. Yet still eye watering expensive. Dials is a bit of a red herring as they weren't the thing then. Again very expensive until rotary embossing and similar tools able to do them by simple rolling were developed. For accurate rotational setting a degree disk and vernier may well have been easier to produce. Ruling engines being established technology even then.
No getting away from highly skilled operators tho'.
Impressive indeed. Herr Pittler must have had a truly amazing ability to visualise not only the solid geometry of shapes but also their production by usefully simple manipulation of the tool approach angle. Previously I'd always thought that the rotating slide carrier capability of the Pittler was pretty much an exercise in being different for different's sake in an era before a generally satisfactory standard engineering metal turning lathe configuration had evolved.
That article makes it clear that the Pittler is more heir to the Ornamental Turning Lathe approach rather than the standard lathe whose evolution is clearly much more directly from the simple pole lathe. Ornamental turning is based on clever tool positioning to create complex shapes and the Pittler clearly follows the same reasoning. Albeit in the more robust form required for machined engineering components.
The skill and care needed in set-up to produce accurate work must have been considerable. Especially if another identical batch of components were needed later after the settings had been changed to do other jobs. Calculation of the settings can't have been trivial either in a world without calculators, log table or slide rules. Objectively a blind ally i machine tool evolution but an impressive one.
Fairly obvious how you get the 200 operations claim. Basically every class of shape counts as an operation. Neil's skepticism aside I think its a valid viewpoint as doing the more complex things on a conventional machine would need a raft of attachments and considerable numbers of accessories for said attachments. Or a CNC. Wonder how a Pittler style CNC would go.
Inherent tool height adjustment too. No shims or expensive QC systems needed.
Trapezoidal bed, twin bevel gear leadscrew reverse and too clever by half worm drive change wheel equivalent system.
Can only be a Pittler. Model B is 3" centre height, Model C is 5" version.
|Thread: Oscillating saws|
Main point when it comes to blade life is not to overheat them. Running too fast in a deep cut kills blades in short order. Especially in wood. Short "stroke" and fine teeth means you have to take care to clear the blade frequently. Its tempting just to push in but, as I found out, thats not the way to get long blade life. Effective at making smoke tho'.
Mine is a Makita which seems good. About £100 delivered, with case, from Lawson HIS at the moment.
Edited By Clive Foster on 11/03/2017 15:29:32
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