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: Tom Senior|
Head removal can be a bit tricky, especially if working on your own.
I made a substantial foot with a vertically mounted R8 arbor to assist removal and reinstallation of the head on my Bridgeport.
Well worth making something similar for the Senior using the appropriate taper to match the spindle.
Although intial fitting needs a touch of care to get the foot securely mounted flat to the table the positive, repatable support makes life so much easier. Especially as table feeds can be used to align the head and studs on refitting.
Extra support for the motor is probably desirable. Some sort of simple bridge should do.
|Thread: Broken Verdict DTI|
I guess not saleable means that the part isn't sold to third parties to repair a broken or worn indicator.
Presumably either a fit / tolerance thing or a judgement that if those parts are damaged or worn out the indicator is beyond repair. Either needing too much work or simply cannot be made to work properly again.
Looking at the parts diagrams I can see why they say that. From a commercial viewpoint anything much beyon a simple crystal replacement or similar easy fix probably isn't worth it anyway. I guess by tghe time all is said and done you'd be into £30+ before anything is done.
When I asked about getting a relatively late version tenths thou cylindrical body one fixed they told me that they no longer did parts and that it wouldn't be worth it. Especially as the innards of those had proven a bit problematical in service. I guess squeezing the 10 ths thou mechanics into a cylinder didn't work out too well although the original, 1 thou sensitivity, A.Capp made versions had cylindrical bodies, albeit much shorter, and work fine. Pity as the long body on mine was handy for getting into close quarters. Approaching 2" into a bore.
|Thread: Tom Senior|
First step is to pull it all out and give the bar and clamp a really good clean. Not just wiping but appropriate solvents too.
Counterintuitively roughing up the surface to "key" things doesn't help. Smooth with maximum mating surface area does the trick. Might be worth applying a very thin layer of blue or, probably better, a solvent based felt tip pen mark or two to verify that you have good contact everywhere.
Best to investigate and sort things properly rather than resorting to quick'n dirty shims to fill the gap. Once shimmed you can never go back.
When used in an environment with oils floating around occasionally moved cast iron components seem to get a bit slippy so clamps loose the holding power. Doesn't matter how careful you are to clean the mating components. If the Gremlins so decree it does happen. Takes a fair few years but if you are on the list they will get you.
For me the major disadvantage of synthetic coolants is that this sort of thing happens much faster and much more frequently!
|Thread: Changes to Fusion 360 Terms|
Further to IanTs comment I think if you made an isolated computer running just windows 10 and SolidEdge it will be safe until the hardware dies,
If you print your drawings to pdf the content should be safe whatever happens.
I imagine that, within my lifetime at least (was 66 in July), a Virtual Machine system to run a dedicated Windows10 - Solid Edge community edition will always be possible.
My MacPro runs OS 10-12-6 High Sierra. Solid Edge seems to be fast and responsive using Virtual Box to run Windows 10. But I've only played with it.
However the MacPro sitting under my desk is pretty powerful. Big old lump tho'.
Mid 2010 version with 2.8 GHz Quad-core Intel Xenon and 24 GB memory.
Graphics card is ATI Radeon HD 5770 with 1024 MB memory onboard.
Main drive is 1 terabyte solid state, three more spinning drives adding up to around 3 terabytes in the box too.
I think on a laptop integrated graphics and limited memory may be the most likely issues once a drawing becomes complicated. But how complicated ....
The laptop I'm writing this on is a Mid 2010 MacBook Pro 17", also on 10-12-6. 2.66 GHz Core i7 processor but only 4 GB main memory and 288 MB integrated graphics memory. So lots less oomph. SolidEdge would maybe go OK under BootCamp but the extra load of Virtual Box might be pushing it.
Link to Solid Edge Community Edition :- **LINK**
You will get a coupe of E-Mails a week from Siemens about CNC, CAD & CAM stuff including links to advice article downloads in PDF format. Advice is all seriously above our pay grade but I reckon around one or two a month make interesting reading.
SolidEdge community edition is a free download and essentially the full commercial version with crippled export capabilities to make commercial use impractical.
My view is that this sort of thing is a job for a decent used computer. KVM switch and MacMini on permanent BootCamp into Windows or one of the similar size PC bricks was what I ought to have done rather than going the virtual machine route.
I always found laptop screens too small for CNC. Tool menu bars get in the way. My Mac laptops have always been 17" but that was never enough for easy working. I use a 24" desktop monitor. With VectorWorks that lets me work on a basic A4 size drawing area with all necessary toolbars and menu items visible. Everything I do prints A4 or A3.
I suspect that when I get to grips with SolidEdge I shall end up going bigger. Got several stuck pixels so monitor is getting past it anyway.
Life is too short for working around undersize screens. My first CAD (sort of) was MacDraw on a Mac SE. CAD on a 9" screen was "challenging". But we used what we had.
Do verify that whatever CAD program you settle on has decent active drawing blow up and fit to screen capability. I've had VectorWorks up past 5,000 times enlargement, and needed it! Also make sure the line joining and object alignment tools are rock solid. If they are not getting things in just the right place is a monumental frustration.
I've always used a trackball. Bigger ball type. Kensington Expert suits me just fine. Silly expensive compared to a mouse but equivalent resolution with a mouse would probably need a yard square mouse pad! The ball just spins for longer moves.
Bottom line is "If you are not comfortable you won't use it.". Better to spend £500 to be a happy driver than £250 to give up in frustration. Or, worse, waste a couple of months trying to get "free" to work and have nothing to show for it. 20/20 hindsight shows I've probably written the book on that.
At least 500 hours to get fully comfortable with exploiting a usefully good program.
Getting to the manage the bits I want to do now stage is much quicker but "Can manage with what I've found out so far. Don't need to know all the clever stuff." Is not a good way to work, Did that for years with VectorWorks and, in retrospect, wasted a colossal amount of time and frustration.
Emgee has it.
In old money terms think of it as £300 or whatever for a drawing board and all the bits. If you just run the CAD program and never connect the PC to the internet after the initial download all the "Windows is different" bits become part of "how to run my electronic drawing board".
Major, major advantage of having a second machine is that you can run a third party, you tube or whatever, tutorial on the Mac whilst learning to drive the program on the PC "drawing board".
I have an older Mac Pro and set up a Windows 10 Virtual Machine using VirtualBox to run the free version of SolidEdge. Its likely that your Mac can run VirtualBox but memory may be an issue. Frankly I'm unsure whether all the faffing about was worth it especially as, by the time all was done, it cost around £200.
But I had to buy Windows10 and made some desirable computer upgrades along the way. A KVM switch to share my big desktop monitor, second keyboard and compact PC might have been better overall.
Don't skimp on the program you choose. Even a simple one takes a fair bit of learning and its a pain to have to switch. Again.
SolidEdge is daunting but it has all the pro bells and whistles.
The 2D part can still be got at separately too. Which is where I shall start. Also verify that there are downloadable books to help you. I found a copyright free one for the 2D part of SolidEdge which is very respectable. Spent £60 on a book for the 3D side tho' as what could be found was old.
Not for the first time I found that trying to be too cheap costs more!
An older version of VectorWorks will run fine on your Mac, if you can find one for "££ not very much" but I don't know about installation. A proper professional program but the mechanical design side hasn't been updated for getting on for 10 years now. The 2D side is solid, 3D more arcane than i want to deal with and £1,000 to upgrade if I change my OS is a rip off. Great thing about the 2D is a very useful library of common bits.
Edited By Clive Foster on 24/10/2020 10:15:55
|Thread: Lidl Portable Bandsaw|
In a practical world how does it compare with the common 6 x 4 horizontal/vertical saw in terms of jobs it can do.
I've had a 6 x 4 for many years but it is now very rarely used, mostly for angle cutting, since I got a Rapidor power hacksaw for stock cutting and 14" Startright vertical bandsaw. One of those would save me space and the portable ability would be handy for out of shop work but I don't want to loose too much capability.
On a side note has anyone considered converting one to a vertical slide type instead of simple pivot. Looks possible.
|Thread: Digital readings|
Indeed. But horses for courses.
The thing about decimal representation is that it matches the decimal number system so its a continuous representation making calculations easy. You just plug the numbers in, do the maths and sort out what it all means afterwards. Scientific folks, like what I was, use the "10 to the power of" scientific notation because it keeps things straight automatically.
But, as Nicholas says, the decimal notation strips the actual measurement unit from the calculation so its easy to loose track of what the numbers mean. Hence the confusion illustrated by steviegtr.
Which can be very dangerous in a more casual situation. Its easily exploited to confuse folk or sell a dishonest conclusion. Objectively most folk can easily visualise the difference between 5, 10, 50 and 100. How about between 10 and 1000. Ummm. OK try 5,000, 5 million and 5 billion. "Well they are all big, the last one is really, really big" is about where most folk check out. Although I'm well able to handle calculation of far, far larger numbers I hit visualisation trouble around the million or so. I've worked with folk who can visualise and truly understand billions. Its rare its hard but the insights can be amazing.
In the imperial system no one is going to confuse an inch with a yard or 1/4" with 19/64 ths. If anyone starts on about 7 miles, 600 yards, 2 ft, 3 and 21/32 nds inches the immediate reaction is "Shaddup Plonker, call it 7 and a third miles." or, more likely about 7 1/2. But I've seen truly serious money, £100 million plus, vanish down a rabbit hole chasing a vehicle mounted system sold fundamentally on a (theoretical) nanometre level ranging ability. Which was meaningless in context.
Folk talk casually about thous and tenths thous but who really appreciates how big they are. OK, OK the 1 thou feeler gauge is the really thin one that breaks almost as soon as you look at it. Now how about tenths thous ...
Sometimes there are reasons for apparently inappropriate units. Aircraft altimeters read feet because the important bit is when they are close to the ground. 50,000 or 50,001 ft matters not at all, 1 ft or 3 ft or 15 ft is important. Little bump, bigger bump or "what did you break this time!".
The aircraft altitude thing is a good example of how folk fail to visualise large numbers. Next you are sat next to Mr or Ms Nervous Flyer and Captain Speaking says "We are flying at a our cruising altitude of 35,000 ft" mutter "Gosh, thats nearly 7 miles up.". Makes Daz and the blue whitener look positively amateur. Folk know what 7 miles is. For me its the distance to the next town over. 35,000 ft is just numbers.
Edited By Clive Foster on 22/10/2020 10:09:31
Edited By Clive Foster on 22/10/2020 10:18:42
|Thread: TurboCAD Layers & Dimensions - Help Please|
I suspect you need a flow chart of how the layer behaviours work and what the correct order of operations is to get specific behaviour.
Things like line colours having all layers and just this layer variants of the command are something you'd expect in a CAD program making sophisticated use of layers.
The difference will be defined by the order of operations and where in your setting up process you make the command. TurboCAD and I didn't get on and parted a goodly while ago but it seems to have very robust protection against single layer changes propagating back to the default level. But not so good at stopping single layer effects from bleeding into another single layer. Sounds like the way you work is trying to exploit a layer to layer bleeding effect rather than doing things the proper way.
A flow chart should help you sort out where the demarkations between default, all layers, just this layer and don't do it in this order because it doesn't actually do what it appears to do.
But personally i've always felt that TurboCAD has an intrinsic tendency to be too clever for its own interface making some things stupidly difficult until you have the Road to Damascus moment. First time through the paper and print size setting thing reduced me to incoherent fury!
|Thread: Car says catalyser is blocked|
Lower gears don't really do it if the DPF system is well clogged. Need to get the motor under decent load and decent revs simultaneously to clear it.
Light footed drivers like me can get the DPF system into trouble even with a theoretically appropriate mix of fast motorway runs. I long ago mastered the art of getting cars with SU carbs settled nicely at motorway / open road cruising speeds with the throttle backed right off. Still applicable to moderating the thirsty Rover / Buick V8 in my P38 Range Rover!
|Thread: Experiences with cordless drills|
Its arguable that the ordianry home shop / DIY person needs better than inexpensive bottom of the range battery kit as such should be better able to cope with infrequent use. In our hands age out is more likely than wear out.
A better breed of machine should look after its batteries better than a made to a low price device. This was especially so with NiCad batteries. Modern lithium batteries are more tolerant of sitting around but better breed charges do look after the batteries better.
Round about the time Screwfix started selling their own brand Embreur(?) tools a friend of a friend switched to those for onsite building work. He reckoned that good breeds, professional DeWalt, Makita et al weren't value for money as they would get broken or nicked long before batteries or drill wore out. The cheaper ones he treated as throw aways. New ones every few months.
I went Makita NiCad for my home kit, special offer price of course, and never regretted it. A friend who went the lower end route, Screwfix in house or similar, ended up spending more than the difference on batteries which rarely managed a year.
I've done the open the pack up and fit new NiCad cells thing on my old Makita battery packs. Marginally worth it. Once.
I've since gone all Makita 18 volt sharing four batteries between hammer drill, 1/4 hex impact driver, twin battery hedge cutter, twin battery strimmer and 1/2" drive heavy duty impact wrench. 18 months in and "Quality remains long after the price is forgotten" seems to apply. Works for me. The big Makita 1/2 drive impact wrench is a total beast!
Never understood why all the cordless drills have such crappy chucks that self loosen when using hammer action.
|Thread: Car says catalyser is blocked|
Technically its the expansion ration not the compression ratio that is varied as its an externally blown engine operating at near constant peak pressure. But trying to think about whats actually going on in pressure terms on the inlet and compression side makes my head hurt! In some ways the set up is effectively very steam enginey notch up et al wise.
Thats a very interesting link Duncan. I'd not realised how closely related the work of Timoney and Wallace was.
I cant figure out how to read it either.
I do have photocopies of 3 papers presented to the Institute of Mechanical Engineers on Professors Timoney and Wallaces work which I could scan and E-Mail if you want to see them. PM me your E-Mail if you want them.
Its disappointing how much valuable work foundered on re-tooling costs.
Concerning the Italian Tune Up I was told that this was actually official poilicy withe the Tilling Stevens / Roots TS3 opposed piston diesels.
A late acquaintance used to service these engines and once complained to a factory rep about the need for regular decarbonising. Which was a fair bit of work on those. He was told to take it the vehicle out for half an hour and "thrash the living daylights out of it". Smokescreen time but the engines ran very well afterwards.
Being a two stroke the TS3 needed to be revved to keep it throat clear but most lorry and bus drivers were reluctant to do this and tended to drive it short shifting, Gardener style, and ride the torque curve. Which worked fine as the TS3 was very powerful for its size and era but clogged things up. That said with lorry / bus chassis design and brakes state of the art in those days an Italian Tune Up or revving it out every time on ordinary roads might have been a touch exciting.
From an engineering standpoint I always think it a pity that the work of Professors Timoney and Wallace on improving the efficiency of these engines was never followed up. Timoney put the shaft carrying the bell cranks connecting the pistons to the underslung crankshaft on eccentric bearings. By turning the eccentrics with a lever the effective stroke of the pistons could be varied. A spring and hydraulic damper connected the two levers dynamically self adjusted so the engine to run at near constant peak combustion pressure. At full throttle the stroke would shorten so mean BMEP would rise giving more power at the cost of efficiency. At part throttle it would lengthen improving efficiency. Given that most of the time a vehicle engine runs of part throttle fuel consumption overall fuel burn would be somewhat reduced. Allegedly 20%+ savings. Probably more as a smaller engine could be used to get the same peak power.
Wallace took a leaf out of the Napier book using the engine as a partial gas generator with a turbine driven by the exhaust connected to the drive shaft via differential gearing. Differential so that the engine didn't try to back drive the turbine. Cycle efficiency improvements of 50% or more are possible with this sort of thing. Obviously best suited to constant loads like generators.
Mid 1960's control systems weren't really up for handing such complexity but the possibilities with modern controls are tempting. The Timoney constant peak pressure system is very good for pollution control.
|Thread: Highlighting Index Lines|
Key to success seems to be getting things absolutely clean right down to the bottom of the line and having sufficient depth of line to work with.
Rules in particular seem to pick up a surprising amount of crud over the years which can be hard to shift. Job for a retired toothbrush and decent solvent I've found. But check the handle in the solvent first. Way back I had one try to dissolve!
Never found anything that worked on the shallow lines found on some relatively modern equipment. Martins comment about black-it and skim makes me wonder if thats the sort of process used on modern shallow lines. The dials on my S&B 1024 show no evidene of actually being etched in the first place. Just thin black lines.
Edited By Clive Foster on 18/10/2020 13:07:25
Edited By Clive Foster on 18/10/2020 13:07:50
|Thread: Diamond Like Carbon|
That direct engine combustion feedback through a quartz window system sounds really interesting. But I'd lay odds on it being something that initially worked well at the demo level before deviating into a quagmire of complexity to make it work properly all, rather than most of the time.
My field was more on the low temperature end of things involving target detection and identification. The combustion aspects, with suitably loud sound effects, were handled by other folks.
New gears for my Commander gearbox were never going to be economically viable. I did ask Quaife after Norton had shut down but the minimum order quantity and cost were way out of my pocket. I doubt if there are more than 500 rotaries out there and most of those will never cover enough miles to kill the gearboxes. Nortons answer was going to be F1 type motor with Yamaha gear cluster. Plenty strong enough but my Norton box with coated innards has a much nicer change that the Yamaha box on my GTS which is the same cluster as the F1. Norton clutch is far nicer too than the Yamaha version which is very light switch in action.
Given the marginal lubrication under racing conditions I'm surprised that Nortons didn't use DLC on the rotary engine main shafts, rollers et al to increase the time between replacement.
50 hp through a C15 type gearbox is impressive.
I learned the Castro R trick via a friend from a man trying to keep a seriously tuned Vincent sprinter from destroying Burman gearboxes. In a gearbox the best thing about R its ability to carry high loads whilst maintaining a relatively thick oil film. So it tends not to squeeze out sideways so easily if a shaft deflects.
Agree wth Ian B that the late 70's, 80's, and 90's were a good time in R&D. A lot of the basis for modern electro optics and engineering refinements surfaced in that era and were polished into usefulness. As, probably, one of the first people to actually demonstrate "imaging" use of a CDD detector I found the speed with which it went from "total crap but if we are creative.." to "more than useful pictures" status quite amazing.
As a sometime professional in the thermal imaging, target detection, target stealthing et al world my initial involvement with DLC coatings was in research projects to improve the life of IR and multispectral transmission windows in harsh environments around mid 1980s to mid 1990s. Especially mutispectral ones which tend to be rather soft and suffer badly from rain impacts in aircraft use. Normal IR windows and lenses covering the 8 to 14 micron bands were not so much of a problem as the materials are closer to glass in hardness. But even glass could use a helping hand.
Expensive back then. Dropping one of the big 12 inch (or more) germanium front elements for IR telescopes on TICM and the like would not have been a good idea. Maybe pushing £20,000 a pop for one experimental element after coating. Worth it I guess to nudge the optical diffraction limits and physical transmission limits and get the absolute best out of a tuned up TICM 2.
On the mechanical side I got Oerlikon-Balzers to coat the innards of my Norton Commander gearbox hoping to finally cure the endemic hardening spall failure of the third and fourth gear pairs. Stretching the old Triumph four speed cluster designed for maybe 30-35 soft tuned twin hp to take 90 odd aggressive rotary ones was maybe a touch optimistic. Especially after lengthening the mainshaft to make room for a fifth gear. Predictably the thing bends under load, the ruler straight power curve and relentless torque of the rotary probably don't help, which is less than good for gears. Norton factory issue SAE 140 gear oil was never going to cut it over significantly more than 50,000 miles. My first try was Castrol R which seemed good for at least 100,000 miles. Coating + R should be a cure. At £800 odd I certainly hope so. I may not live long enough to find out!
The idea of gold plating pistons to reflect IR sounds a touch off to me. When it comes to reflecting IR smooth and shiny is fine but at combustion temperatures there is a good deal of visible in the mix which needs a polish. I'd expect the gain to be more from carbon not sticking helping keep the surface smooth. Of course carbon black, which effectively is what is deposited inside an engine, comes about as close as any easily gotten material can be to a perfect black body over combustion emission wavebands. It absorbs nearly everything that hits it, warms up and re-radiates. I'm surprised you only lost 80°C off valve head temperatures and, I guess, 40°C off the piston crown. I saw claims that at least double that should be possible with appropriate coatings. And got to check the maths.
But the field was always rife with over-optimistic speculation and misinterpretation. I'd like a quid for every time I had to explain that you can't reflect cold. If you want to be malicious you can do a really pretty lab demo tho'.
Edited By Clive Foster on 15/10/2020 13:30:21
Edited By Clive Foster on 15/10/2020 13:30:42
|Thread: Milling vice recommendation|
As ever when constrained by budget its worth looking at what you loose out on when comparing the affordable reality with the high end "if I win the lottery". Stretching the £s too far to meet a specification at low price often doesn't work out too well, as I know to my cost.
Blows your budget to smithereens by £100 and may well be too large for the SX3 but, if you need a wide opening, the Vertex VJ400 from Rotagrip **LINK** is an excellent vice and the three nut positions give full depth opening right out to 180 mm making it very versatile indeed.
Most vices have essentially square capacity where opening = jaw width.
I'm very glad I saved up for a pair to put on m Bridgeport. Basically a hydraulic vice made affordable by using a screw instead of hydraulics. Same thing is made with hydraulics at over double the price.
I've always had doubts about the Kurt angle lock anti rise system and clones thereof. Suspect most of the Kurt advantages are due to quality manufacture not the geometry. Seems to me that to be properly effective the pull down tongue should be pretty much under the jaw face not some way back. But Chick is the only design whose kinematics I fully approve of.
Realistically if wide opening capability is going to be important you may well be better off getting a smaller vice for vice work and learning to be creative when clamping to the table. I find that for much of my work a smaller vice would have been fine but, working 12" to the foot scale, the wide capability is often used.
|Thread: Bridgeport feed control lever|
Time to take it all down, clean, inspect and carefully re-assemble.
Hopefully just crud build up due to under-use. As Tony says normally the system snaps out quickly and positively. It also responds well to adjustment if in proper order.
Don't forget about the doubled up grub screws used to ensure that some things stay locked up tight. If the bush that the manual feed lever runs in has managed to unlock, or never been porperly locked up, and shifted sideways a touch it can upset the overload clutch action.
Generally a strip and clean is good for a decade of proper operation. So do it nce, do it rigt and just use it.
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