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: Adjustable Angle Plate or Tilting Vice|
I've got, or have had, all varieties and would agree with Jason that the adjustable work table is most likely to be satisfactory for a wide range of work. Often slowest to set up and, out of the box, tilt angle is frequently limited to 45° or less. If I had one like that in Jasons picture as my one and only and had regularly used angles I'd seriously consider making a new support arm with plain drilled holes suitably positioned to get the angle instantly. Unless fitted for a gauge block stack, sine bar style, getting an angle dead nuts can be a pain. Pretty darn close with a protractor is easy tho'.
Bearing in mind that my mill is a Bridgeport and work is frequently 12" to the ft scale, so my rigidity requirements are perhaps somewhat more exacting than those of folk with smaller machines my personal assessment is :-
1) Inexpensive type angle vice with two pivoting side plates. OK as a drilling vice but may well be iffy as a milling vice unless only using very light cuts. Time was that the machining, manufacture and alignment standards were poor. Fair few articles written on how to measure and correct errors. One of the import products that cemented the early reputation of "kit of parts supplied assembled to save printing instructions". Consensus seems to be that once reworked you had a very decent device for a very modest outlay. I wouldn't know, mine hit the scrap bin so hard that it nearly bounced out! I'd hope that, in line with much of the other imported equipment, quality standards have risen since so that they can be used out of the box. However the precision needed to be really good is deceptive and I suspect the market won't accept a commensurate price.
2) Inexpensive angle vice with part circle pivot runners each side and locking screw one side to hold the setting. Drilling only. Which was what mine was got for. Seriously chancing your arm if you expect it to stay in place when milling. Mine came from Northern Tools (remember them) at a very attractive price and is quite accurate with negligible twist between vice jaws and pivot axis. Better than I expected actually. Still comes out for appropriate jobs.
3) Proper pivoting vice with part circle recesses in base and matching runners in under the vice body with two bolts to hold the setting. Mine is a 6" Abwood on a rotating base. Very heavy, crane onto table, and rock solid. Needs a screw jack underneath to adjust it. Lord knows what it cost new. Can't see that quality at import prices but the design is inherently solid. Be advisable to check the alignment of the vice jaws and pivot axes to quantify any variation with movement. Unlikely to be anything that can't be worked around or fettled out.
4) Adjustable angle plate. Mine is a British made one of the style having a more or less semi-circular base with the plate running round it. For my money the most solid type of angle adjustable work support likely to be a accurate at a modest price. Often advisable to bolt a handle on to the plate to help with adjustment.
5) Adjustable work table. Best ratio of carrying capacity to weight. Not something to be overlooked when lifting onto the machine. Simple design means its easily made to decent accuracy at modest price. Not as inherently stiff as no 4 but up for all rational cuts. Major disadvantage is that its not a complete solution out of the box. Need other devices, like Jasons angle plate, to do the actual holding. But you should have such things anyway and, even if you need to get them, they will find plenty of other uses. Although vices are convenient they can be dreadfully limiting. Mine is a double one that tilts in both directions with fittings for gauge block stacks. When you need it there is no substitute but jobs really needing it are best avoided unless well paying.
|Thread: Emco V10P carriage stop|
Looks as if you have a small vertical step at the bottom of the triangular guide on each side. A simple rectangular slot engaging on those vertical steps would probably give sufficient location when fixing a bed stop. Less than elegant tho'. The job would be neater if something fairly close to the triangular section above the vertical steps is cut by whatever means you have and the gap filled with metal loaded filler. Press the filled slot onto a well lubricated section of the bed to get the shape just so. Once its painted the filler won't show.
One advantage of the using filler to get the right shape on the triangular part is that a fairly rough job is actually better than a super smooth machine finish as giving plenty of nooks and crannies for the filler to grab. The good metal loaded fillers tend to be moderately expensive and come in pack far to large for a single small job. JB Weld is easier and cheaper to find and works well provided the layer isn't silly thick. Advisable to put dams of some sort in if using JB Weld as it can slump. I've used duct tape and plasticine for dams in the past. Worked well enough.
Johns drawings show a functional and good looking device.
The bedstop for my Smart & Brown 1024 has the clamp fixings on top of the stop rather than, as is more common, below. Two bolts with square heads same size as the ones on the Dickson tool fixing bolts so the spanner is always to hand. I find this a very convenient set-up.
Edited By Clive Foster on 23/04/2018 15:33:54
|Thread: Compressor Oil|
Essentially its an older relatively low additive oil formulated for engines that spend significant periods stopped and have widely varying load / speed ranges. So it has a decent amount of anti-corrosion and anti-condensation properties. For all practical purposes anything up to, but not including, SM works just fine on older automotive engines made when earlier designations were current.
420 is the viscosity. presumably in Saybolt SUS rating at 100°F as nothing else I've found makes anything approaching sense. Straight SAE 30 covers about 380 to 600 SUS at 100°F so presumably would be a modern equivalent. Basic hydraulic oils are popular for this sort of relatively undemanding application but do make sure you have decent amounts of anti-corrosion and anti-condensation in the specification. If going the hydraulic oil route note that ISO grades are specified at 40 °C so are closely comparable to SUS at 100°F although the numbering is quite different.
One thing to be careful about compressor oils is "off-duty" cycle. Many compressor oils are formulated for industrial devices that run most of the time. Some oils can be unhappy if left to stand for long periods. The special oils for Hydrovane compressors are a case in point where its important that the beast be got up to temperature when run so as to drive out any condensation.
Personally I just shoved a decent brand SAE 30 automotive oil in my Atlas Copco KE 2 with an oil change when I thought about it, probably every 3 or 4 years. The Atlas wasn't new when I got it 40 odd years ago but its been going fine on that sort of service regime ever since. I've sold it 4 times and taken it back 3 times so far when the current owner decided to copy me and go Hydrovane for peace and quiet in the shop. Perhaps I'll look at the valves next time it comes back. Or perhaps not!
|Thread: Care of Slip Gauges|
Seems like Starrett M-1 oil is the right stuff but seems to be unobtanium in the UK. Does anyone know a source at reasonable price?
Apparently white spirit is the UK equivalent to the American mineral spirit advised for cleaning purposes. But which brand of white spirit to use. Seem to be considerable variations between them. Some of the more economical offerings appear to be a bit dubious from the residue aspect and, probably, chemistry too.
|Thread: Worm Gear Drive : What do they mean by that ?|
Well it is Edmunds economy range so maybe they just used the helical rack out of the small rack and pinion drive stages **LINK** . The meshed a special screw to it and figured out a fancy name that sounded a lot more meaningful than it really is. They are an American company after all. Such naming issues has always been a monumentally irritating American habit. (Knee Action suspension or Pic-O-Matic Gearbox anybody!)
Those in the above link to are basically microscope focus drive systems so the pitch is almost guaranteed to be weird. Allegedly due to the space constraints on rack and pinion for acceptable helix angle but I suspect the guy who fed me that line was trying to be clever and really hadn't a clue.
Pretty much irrelevant anyway as you'd never use graduations on any job that suited that sort of lower end kit. Dunno if Edmunds have gotten their quality up since my working days (pre 2004) but back then I'd not touch any of their mechanical stuff with a barge, let alone the pole. Optics purchases were usually desperation items when Mr Project Manager refused to pay attention!
Wormscrew and racknut,which I think is the correct terminology, is hardy perennial in alternative to leadscrew drive systems.
One of the optical lab equipment stage makers had a section in its catalogue explaining the relative advantages of micrometer, leadscrew and racknut drives as they made all three types. Unfortunately I left that catalogue behind when made redundant so don't have the details or even recall the firm. Old so certainly binned by the twit with a Phd who took over. MIght just as well have taken it with me. My guess-recollection is that it was said to give better stability and higher axial load capability than a comparably accurate leadscrew. Especially in vertical applications. Probably the only compact type with acceptable performance if you have to use things with a vertical push up, i.e. knob at bottom, arrangement. Bad practice but sometimes inevitable.
Uncalibrated movement probably isn't an issue for that type of device. Although pretty much all my really precise gear had calibrations, good ones too, it frequently surprised me how rarely I exploited the calibrations. Usually worked by educated twist of the knob to zero out fringes, maximise detector response or best image quality.
Victoria used a similar system for the Y axis drive on some of their P, U and V series machines. Arranged to have pretty much 100% wormscrew and racknut engagement through the whole travel. Presumably the theory was that uneven wear would be minimised. Didn't seem to have worked out like that on the one I had to help make a new racknut for. About a foot of phosphor bronze bar cleaned up to a precise rectangle to match the slot in the casting with about 1/3 radius of a thread cut on the business side. Went banana in about 6 directions when unclamped! We got it straight. Eventually!
|Thread: Obtaining flat bronze bar|
If my experiences are typical you will need to take account of the stresses locked into the phosphor bronze bar when it was made. If there are significant locked in stresses and substantial amounts of metal are removed in a non-symmetric manner the part may twist considerably when released from the clamps after cutting to shape. Getting it back to the desired shape generally requires perseverance, creativity and verbal encouragement. Problem is best avoided in the first place by appropriate technique.
Hopefully someone here with more experience than I can advise as to best technique.
Used off the shelf PB bar to make a rack like "quarter nut" about 12" long for the Y travel on a Victoria milling machine. Twisted considerably in about 6 different directions when unclamped. Think demented banana with serious tummy ache! Straightening without destroying the screw thread accuracy was an adventure! Seems to me that your basic shapes, albeit without the thread to complicate matters, will be somewhat similar so there may be a risk of the same sort of issue.
|Thread: Bridgeport Plug|
Agree with V8Eng that its almost certainly a Niphan connector. Old style sealed joint rough duty connector. Very, very expensive new these days. Far as I know you have to order direct from the maker. I suspect there is a minimum order charge and minimum quantity requirement too.
Might be worth asking Sorted Machine Sales **LINK** as they sometimes have second hand parts.
|Thread: Bridgeport Turret Mill series 1 X axis power feed|
The Bridgeport-Mill Yahoo group **LINK** has a pretty comprehensive set of data on the Erskine boards in the member files including a typical circuit diagram and typical component lists. Members only access so you will need to sign-up. Which may take a day or three depending on how grumpy Yahoo is feeling when you ask to join!
Sorted Machine Sales do an exchange service **LINK** . Base price is £109 but VAT and delivery to go on top.
Unless you are an electronics person with reasonable experience and some knowledge of older style motor control electronics its probably best to bite the bullet and splash nearly £150 on a known good, properly sorted unit. I have some electronics expertise and ought to be able to fix one but, after a quick look, decided that life was too short for DIY.
|Thread: drill / mill table load|
Although milling in an ordinary pillar drill is generally considered an unsatisfactory, even dangerous process, the Fobco is designed to be capable of light milling.
Fobco bottom spindle bearings are an pre-loaded angular contact pair of the style common in milling machines and are well up to the loads. The screw on cap spindle is intended to take morse taper collets of similar style to those used by Myford giving both good grip on the cutters and minimal projection.
Its not proper milling machine tho'. Performance is limited by the relatively small diameter quill which is inevitably less stiff than that on a proper milling machine. The fine downed arrangement is little rudimentary and not as positive as that on a proper mill. I would hesitate to use one without the fine downed for milling duties. Although things will certainly work from the cutting perspective getting exactly the right depth of cut may be challenging.
It is what it is and certainly well up to handle appropriate sized milling cutters. In my view its best suited for jobs like spot facing, smoothing out faces and cutting flat bottomed slots or recesses where decent surface geometry and finish are the aim rather than precise depths. The pillar drill style depth stop is entirely adequate for jobs where 10 or 20 thou absolute error is fine. You'd need to work much harder to do significantly better on a routine basis. No substitute for fine downfeed really.
Were I intending to try more serious milling work I'd look into arranging a much more positive depth stop with integrated "display on a stick" depth reading device. I'd be unsurprised to discover that thou' or better depth accuracies could be achieved by working to a stop in this manner. Certainly the essentially similar arrangement I made for my square column Chester Lux style mill could achieve such accuracy. Making an accurate vertical cut on a Fobco would probably only be possible by setting the depth stop first. I found such work was doable but something of a faff on my mill but I'll not claim that my particular depth stop and readout system was the best that could be produced but it worked adequately with a fine down feed.
Extra table support is essential. Bottle jacks can creep and ordinary automotive scissors units are flimsy. Old style bevel gear driven vertical screw jack would probably be the most secure. Come up fairly regular on E-Bay or boot fairs. Ideally you'd want a finer screw thread.
Edited By Clive Foster on 12/04/2018 10:05:14
|Thread: Argon gas|
I know of fire extinguisher CO2 being used by a pretty skilled welder as a field expedient. Said his set up was somewhat tricky and not something for the lesser skilled to attempt. Considerably harder to get good results than with the pub gas he usually used for his own work. Told me not to even think about it.
Never met anyone who could clearly explain when feed heaters were needed on the ordinary range of jobs in reasonably habitable conditions. Always figured that such were frequently just a precautionary measure to ensure there would absolutely not be any freezing problems.
Really you have to consider the target audience for normal workshop use of the technique. Most folk considering using fire extinguisher CO2 will most likely be working hard to make 5p fill in for £5. Odds are limited experience . With equipment not of the best. Either old, inexpensive or both. Wire feed issues pretty much guaranteed either way.
Such folk really need as much as possible to work by the book and exhibit the classic faults for trouble shooting. Gas source problems from a home brew set-up really won't be helpful. Especially if the difference between workable and serious trouble is something obvious to the experienced man but easily overlooked by the neophyte. Unfortunately all too common on You-Tube "worked for me" videos.
Making clear, unambiguous, easy to follow beginner / inexperienced viewer friendly videos is Hard. Very Hard.
If you are really light user those daft 1 Kg re-fillable bottles from Sealey may be worth considering. About 1/2 cubic metre at atmospheric pressure if my calculations are right. Allegedly 3 hours worth. About £20.00 a refill. Priced to look good against the disposables which are half as much for over twice the money.
Murray gets a better deal at 10 hours and over per year but fits'n starts folk like me loose out on the rental. Must be 3 or 4 years since I last fired up the MIG. OK I burned through three or four 1 Kg bottles but still well ahead. Really helps having a first class inverter stick welder so MIG is strictly for the really thin stuff.
Allegedly you can get a, presumably empty, 1 Kg bottle off Amazon for £12 ish which makes it possibly worth while. Full prices are over £70 which is plain daft considering they are basically just a re-painted baby CO2 fire extinguisher.
Now the pub landlord route has been closed off I'm surprised there aren't more folk up in the peanut gallery advocating shoving an adapter and regulator on the output of a common 2 Kg or 5 KG CO2 extinguisher. As such can be found at around £30 for 2 Kg and £80 for 5KG outright purchase it certainly looks attractive for the very light user. Especially on You-Tube. Leaving aside the fact that most hobby MIG wire feed rates generally aren't really stable enough for easy welding on pure CO2 there are all sorts of potential issues glossed over, like regulator freezing. I know it can be got to work, sort of ish, but no way would I try.
|Thread: New workshop building advice.|
Concerning the proposed roof layout consider integrating your workshop roof into the main garage roof giving a continuous fall. Probably need to put a slight bend in the fall and loose a bit of height at the far wall. Less than ideal but should you have roof problems in the under gutter region they will be a major, expensive, PIA to fix post build.
Its also possible to put a gutter or similar drainage between two roof sections.
Best to talk to good builder with relevant experience.
What you are proposing with the single skin brickwork isn't vastly dissimilar to the low side of my timber frame workshop which is about a foot above ground level. Need daylight to check but as I recall matters there are only two courses of brick above the slab with the DPM between as in your diagram.
However I have serious concrete under my floor. Bricks were laid all round first on normal foundations as required then back filled with concrete. About a foot with mesh re-enforcement, then a polystyrene insulation layer with 6" more concrete on top and, finally, the waterproof, green finished, chipboard under-flooring sheets used as is for the floor surface.
Noise shouldn't be an issue. I have 4 x 2 framing with OSB both sides. Fibreglass insulation between the OSB and painted shiplap outside. Proper house type double glazed windows. Anything short of an angle grinder or similarly seriously loud equipment is essentially inaudible outside.
|Thread: How to paint aluminium|
Another disadvantage of wire wool is ferrous metal surface contamination which is known to reduce paint adhesion to aluminium even if otherwise properly prepared and effectively etch primed. Pretty much impossible to stop microscopic particle common off the wire wool and becoming embedded in the alloy surface or reforming oxide layer.
|Thread: calculation for nod on milling machine|
Assuming you have holes in the shims for the bolts to go through.
Ratio of the shims to your measured error is the same as the ratio of the measurement diameter to the bolt spacing.
Measured 0.17 mm error in 200 mm so if bolts are 100 mm apart you need 0.085 mm / 3.3 thou of shims.
Edited By Clive Foster on 02/04/2018 22:38:06
|Thread: Trying to find some D1-3 back plates|
As far as pin threads for DIY are concerned perm one from 7/16" UNF, 7/16" BSF, 10mm x 1 or 10mm x1.25.
RDG usually have them around the £20 - £25 mark for a set of three would make sense to buy at that price if you only needed one set. Getting spendy for four though. However other common suspect suppliers want around £20 each!. Allegedly not that tricky to do but needs a decent jig and proper set-up to machine the cut out. When I looked into it, for D1-5 pins which are hard to find, plan A was to screw the cylindrical blank into a suitable chunk of metal held in the milling vice so all the cut outs were timed the same relative to the thread.
Main issue with making backplate is getting the taper depth relative to the flat back just so. Tolerances are pretty tight for Home Shop Guy. My plan was to make a gauge with an over length taper and measuring reference flange a suitable distance from where the backplate surface ought to be. Idea was to start off with an over thick bang for the backplate and machine the taper a bit too deep. Comparing the measured distance between the gauge flange on a known good backplate with the part made one would tell you how much to face off the backplate rear surface for proper fit. Ought to work provided the gauge were presented dead in line. I imagine pushing on a centre hole in the rear of the gauge with a dead centre in the tailstock should ensure alignment.
A plausible alternative would be to make the taper in a separate plain diameter part loctited into a matching bore in the home made backplate. Pushing the taper carrier into place with everything assembled onto the machine ought to get the longitudinal position right.
One thing I never did figure out was how to ensure that the tapped holes in the backplate for the studs had the threads in correct rotational tolerance. Thought that if the threads started at different angles the cut-outs could end up at the wrong distances from the back so the locks could never all pull up. Never figured the geometry out though so perhaps a 1 thread pitch error isn't enough to take the camlock out of the 1/4 turn safe range.
Gloster Tooling shows semi finished 120 mm ones for £44. Dunno about tax and postage. Only dealings I've had with Gloster were for 5C collets which were decent quality and value.
Rotagrip site doesn't give me prices for semi finished ones. Bought a semi finished D1-4 for a PB chuck from them many (15+?) years ago which has been fine. Not cheapest, about 1/3 rd price of official PB one, but decent value from folk I trusted after previous dealings. Bottom price feeding on tooling those days could be very, very risky.
Surprised that Warco supplied you with some that flat out did not fit.
|Thread: Bridgeport Series 1 Varidisc Head Bushes/Bearings|
General recommendation is a high strength cyanoacrylate with a suitable primer to modify the Delrin surface and promote adhesion. For example :- **LINK** .
I've done well enough using ordinary cyanoacrylates and high strength loctite to retain simple bushes after lightly abrading the Delrin surface first. My shop made Delrin replacements for the turquoise "moulded in place" Varidisk bushings appear to be holding in there just fine. 6 years and counting! I doubt that it would be strong enough to hold a stressed joint though.
Maybe this stuff **LINK**. is the real deal. Says its for Delrin on the blurb. But being an epoxy I wonder if the joint line may be too thick for Varidisk bush retention.
Edited By Clive Foster on 27/03/2018 09:28:39
|Thread: Couple of things at Lidl|
I have one of the electric impact guns. It is good value and pretty effective but in practice the specifications seem to be a bit optimistic. Somewhat bulky and I'm not completely sold on under car with 240 V electrics but a proper pro level windy impact gun is approaching ten times the price. Doubt if there is much to choose between it and the Machine Mart et al DIY windy gun offerings.
I doubt if it will shift anything needing much more than about 250 Nm / 180 ft lb to undo. Maybe clean dry oiled threads just tightened up but filthy dirty under the car. Nope. My rule of thumb is to expect that under the motor may take double what it was done up to. Had to resort to the 6 ft scaffold pole with 3/4 drive short extension welded on crossways to deal with something brake related under friend Mikes VW Touareg. But it zipped out the impossible to see, foot or so inside, top rear damper bolts on my P38 out so fast that I thought the socket had cammed off. Book says torqued to 92 ft lb, and they certainly weren't playing ball with the standard 1/2" breaker bar. With EAS wiring and air suspension pipes in very close proximity thats one bolt you really need to be certain of good socket & drive alignment when tackling.
Edited By Clive Foster on 26/03/2018 10:02:26
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