Here is a list of all the postings mgnbuk has made in our forums. Click on a thread name to jump to the thread.
|Thread: Scraping a magbase|
I dont even own a set of feeler gauges
Must be the cheapest bit of precision measuring kit going - and readily available pretty well everywhere.
|Thread: Question about Harrison lathe|
A replacement gap piece may well be unobtainable. They are usually fitted and finished along with the bed, with perhaps a scraped surface as well which makes the piece individual.
The gap piece is scraped in, fitted & pinned to the bed casting before the bed formation is milled, heat treated & finish ground.
If anything is available (which, for a lathe of that age from a builder who no longer manufactures, is very unlikely) it would be a part finished casting that would require fitting to your bed casting & then machining through (bed regrind) to get proper alignment. If you were to find the gap piece from another similar model the same would apply.
Could you check back with the people you bought the lathe from to see if the machine's original gap piece is sat under a bench somewhere ?
|Thread: Scraping a magbase|
Have you run a 0.001"/0.0015" feeler gauge around the joint when it is on the surface plate ?
The feeler will enter at the gap & show you where you don't want to be acraping - it is easy to rock a part when bluing it & get a false sense of what is touching. My former fitting colleagues used to thump all four corners of (larger) parts when placed on the plate to feel if a corner was high & not resting on the plate, then work the diagonally opposite corners until the part sat flat in contact. Only then would they start to work on getting alignment & when close to alignment start working on getting a good bed. They always checked around the part as they progressed with a thou (0.001" feeler gauge ("tester" & when getting close would refer to progress on the part as being "tester tight".
Most feeler gauge sets don't include a thou gauge, with thou and a half being the smallest - Starrett sell thou feeler strip, but only in long rolls (used to be arounf £40 a pop).
|Thread: Power Hacksaw Blades|
I'll bet there'll be some on eBay at silly prices.
Depends what you call silly - searching for "power hacksaw blade" gets quite a lot of options from £9-£10 posted. Not too bad a price for a piece of HSS 18-21" long x 0.075" thick delivered ?
|Thread: why does my makita go pop occasionally ?|
If it just occasionally pops the runs OK again it could be a short through a build up of carbon dust around the brush holders. Used to see this quite a lot when DC main spindle motors were in common use - usually the drives would shut down with an overcurrent alarm, but when checked there was no measurable short as the flash over had burned the carbon build up away.
|Thread: Chinese DRO opinions|
Are the covers that fit over the glass scales made from plastic and how do they fit to the scale?
Aluminium angle extrusions on the kit I bought. The extrusions will require drilling to attach to the scale mounting brackets (or to additional brackets mounted on the machine if the scales are mounted directly).
That seller is in China and he has dreadful feedback.
Unless the Chinese have renamed a town Dunstable, the items are shown as shipping from the UK - the quoted delivery date would suggest that is the case.
And 12 negatives in the last 12 monts vs 960 positives is "dreadful" feedback ?
A more pertinant "negative" would be the point in the description that I missed initally - the listing is for 2 nominated scale lengths, with no option to select these. This may or may not be of use to the OP.
is from a UK source, so shouldn't attract import fees.
I bought a 3 axis kit (£224 delivered from UK source) last year - supplied in two cartons (one with individually boxed scales + mounting hardware, the other the readout & mounting arm) whaich came in under a week. Strangely the scales were delivered by Hermes & the readout by ParcelForce on the same day.
Had the whole lot connected up on the bench to check it all functioned (which it did), but still "ongoing" with the fitting to the mill, so no actual usage experience.
Edited By mgnbuk on 15/01/2020 20:29:49
|Thread: angular contact bearing selection|
If we were battling space limitations we used INA ZARF or ZARN bearings ZARF
but not hobbyist friendly prices. You could make up something similar with a drawn cup needle roller bearing for radial support & back to back needle roller thrust bearings either side. This should give a more compact arrangement than angular contact bearings.
|Thread: Clarke CL500M Mill Head|
The Clarke parts list is available here
and the Operating manual here
May help ?
|Thread: angular contact bearing selection|
IIRC "proper" ballscrew support angular contact bearings are a different contact angle to "regular" versions - 40 degrees springs to mind, versus 25 degrees for the standard types. At my last employment we used to specify IBC cartridge bearing units that came in a housing with a flange like these
Similar units of Chinese manufacture are readily available from Ebay & the likes at far more hobbyist friendly prices like these
Be aware that the "fixed" end bearings are the ACs - the "floating" side is just a standard single row ball bearing.
Both flanged bore fitting and flat surface pillow block mounting types are available. At the kind of pices these go for I wouldn't bother trying to make my own.
|Thread: Electric welder at Lidl|
Includes: welding wire, burner nozzle, 4 welding nozzles, welding shield and chipping hammer with wire brush
Can't find a manual for the "B2" variant, but the "A1" appears to be a plasma cutter. The description above appears in the current model description & suggests that this device can be used both as a welder and a plasma cutter. As I have a job for which a plasma cutter would be beneficial, I'll have to have a look at the box in store to confirm the details.
|Thread: Choice between cheap mini milling machines.|
Are you sure it includes the rotary table. Yes, in the pics but not in the description? Are you sure it includes the rotary table. Yes, in the pics but not in the description?
Seller's description has terminology issues, but I read it as including everything as shown in the pictures :
"Warco minor Mill/Drill, 1hp motor 240V. good condition, comes with stand which can be unbolted and some extra bits. Clamping kit, vice, some cutters, drill chuck, no drill bits, rotary dividing vice, tool holder."
Andrew - if that is too big, then the smaller bench top machines are really your only option & you will have to operate within their power / rigidity limts, both of which will be a lot lower than a modest "Minor" type mill/drill.
If you can find one, an Emco FB2 bench mill (or clone - various sellers sold Taiwanese or PRC copies a few years ago) is a better bet than the modern variants IMO. Still a 120kg machine though. I have a clone ("Ajax" base & table with a "Denford" column & head) & won't be changing it any time soon. I wouldn't bother with a Chester Champion - which I looked to buy before the FB2 came up. Similar base & table design to the FB2, but inferior head & column design, with less rigidity & poor speed range.
Finding the right mix of fit for space, fit for purpose & fit for pocket isn't easy - good luck !
(sorry for the mix of text size & font - can't seem to find away to edit it)
Edited By mgnbuk on 04/01/2020 16:25:29
Edited By JasonB on 04/01/2020 16:44:32
What you need is a second hand Warco (or equivalent Minor mill-drill.
One on ebay at the moment item number: 303431719522. Includes Autolock chuck, vice & rotary table and currently no bids at £200 start price.
|Thread: What Did You Do Today 2019|
Spent most of the weekend sorting out in the garage to make room for my Denford Triac 200, then dismantling the machine and getting in home - brought about by having to move it from the storage location it has resided in for the last 12 or so years. Just the stand to get home now, which can live outside for the time being. As an ex-industrial machine in rather grubby condition it needed to come apart for a clean & check over before getting a new PC + stepper motor control system added, so no extra work done getting it out this way.
Forgotton how awful rancid coolant and old oil smell & still picking swarf out of my hands, but the precision bits are now in my garage. I weighed the bits out of interest & found that the heaviest casting - the column - is 59kg, so no wonder I was puffing a bit carrying it to and from the car. Probably going to feel that over the next couple of days ! The basic structure of the machine, excluding the counterbalance weight, comes to around 210kgs - quite a lot for a compact 600x200 table, 320mm x 150mm x 320mm XYZ travels machine.
As a result of the tidy-up, I now have a bit more room to move around the garage than before the arrival of the Triac, but not enough to work on it. Something from the "projects I will probably never get a around to" collection will have to go next year to make more room. I do seem to do "acquiring" rather better than "disposing" though.
|Thread: Bandsaw woes.|
What pitch blade were you using ? Wider cuts require a coarser pitch blade to prevent the gullets getting clogged - clogged gullets give rise to a wandering blade.
If you can't fit a blade with a coarser pitch, reducing the feedrate to the point that the gullets don't clog will also help prevent the blade from wandering. On the bandsaws at work we had similar problems (600mm deep cuts in graphite) & enlisted the assistance of the blade manufacturers. The blades were changed to the coarsest we could get (2 / 3 TPI vari-pitch) & reducing the feedrates to the point that the gullets didn't get filled largely solved the problem. That on top of ensuring the blade tension was correct (the saw blade rep used a tension gauge to determine that, on our machines, correct tension was with the adjuster as tight as we could get it) & that the moving guide was set close to the block.
|Thread: What is it|
Possibly a tacho generator ? Colour & painted on markings look like those seen on military equipment, so maybe a TG from an engine to drive a tachometer remotely on an instrument panel. If you have a DC meter, try connecting to the terminals & spin the shaft to see if it generates a small voltage - the voltage will be proportional to the speed.
I've used similar looking devices for speed feedback on machine tool spindle motors - usually 60v/1000rpm in that application. No real current available, though - the windings are optimised to provide an accurate voltage with low ripple.
|Thread: Another "What is it"|
NPL refers to the National Physics Laboratory - the go to place for anything to do with measuring, based I seem to remember around Glasgow.
NPL is in Teddington. The National Engineering Laboratory was / is based at East Kilbride outside Glasgow.
|Thread: Unsolicited email from SOLIDWORKS|
You can get personal access (non commercial use) to Solidworks Education Premium for $40 year.
How ? Join the Experimental Aircraft Association (www.eaa.org), where it is one of the membership benefits. Needs a pretty capable PC to run it, though.
|Thread: Why mostly manual cars in UK|
I’d hate to see the repair bill for a modern auto box though.
You probably wouldn't, as increasingly manufacturers are not making parts available to repair them, just supplying complete new gearboxes. In the case of the CVT gearbox on the Toyota Avensis I had that was £4500 + fitting costs around 5 years ago. I had requested (twice) that they change the gearbox oil, but on each occasion the dealer (who had quoted a price to do this) subsequently declined, saying that Toyota said the gearbox was "sealed for life" & didn't require an oil change. When the gearbox bearings started whining at around 80k miles, I was then told about the "no parts" policy. A local auto gerabox specialist had managed to source Chinese made pattern parts to repair a similarly affected Avensis private hire car, but he was still looking at £1500 for the repair. So the Avensis went & I won't buy another Toyota.
The torque converter auto Kia Carens that replaced it did 75k miles without a problem - hopefully the 7 speed DCT Hyundai that has recently replaced the Kia will be as trouble free. The DCT has a different "feel" to the conventional auto, but I am enjoying putting around 10 litres a week less in the tank (mid-50s average, compared to mid-40s on the Kia. Both turbo diesels).
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