|Thread: Why is my silver steel undersize|
Posted by BOB BLACKSHAW on 19/01/2020 10:46:06
I also noted that the 8mm rods from old printers are undersize by .08mm which I've used for axels and made bushes to fit,any reason why?
Maybe because they are 5/16";
7.92mm = 0.3118"
5/16"=0.3125" only 7 tenths of a thou different
Where were the printers made?
Edited By peak4 on 19/01/2020 11:14:43
|Thread: Mobile Phone|
Yes Tesco Mobile used O2 as an airtime provider.
If you go to Google Store and have a look around, there are a number of apps which will tell you which cell site to which your phone is currently registered.
Netmonitor is one such app, but there are others, I can't recommend one over another.
|Thread: Biax Power Scraper|
Posted by John Waller on 17/01/2020 23:34:12
Hi Bill - Thanks very much for your message - always appreciated.
I've already now got two Biax scraper
I realise that, but thought someone else might be interested in adapting it .
I'm not sure I could justify a real one, or the time involved making one, though the Instagram link is interesting.
Just by coincidence, this has just popped up in my inbox.
No intention of buying one myself, but thought it might be of interest.
Arbortech PCH350 Power Chisel
|Thread: Myford super 7|
To help people to help you, and I'm most certainly not one of the experts, it might be useful to post photos of, the setup, the finish, and the tools.
Also tell us what RPM and feed you were running.
"Mild Steel" can come in a whole range of varieties, especially if it's come out of a scrap box, and you've no idea of its origins. Some turns beautifully, the finish on other stuff looks like it's been pebble-dashed.
1 ¼" bar is a reasonably large diameter in some ways on a Myford; does it fit up the bore of your 3 jaw, or were you just using the section of the jaws in front of the chuck body? If the latter, and without tailstock support, particularly on a worn chuck, the finish would likely be compromised.
Don't worry about setbacks for the time being, all will progress well given time. ( I hope anyway as the 8" square plate I've just faced looks appalling. )
|Thread: Drilling holes using pillar drill - work wobbling|
I'd suggest that with your previous drill press, any wobbling through misalignment was taken care of by the quill and chuck wobbling about.
Now you have something more rigid, that's transferred to the end of the drill.
Also, is you 8mm bit new, straight, and ground evenly?
Yes various ways of clamping the vice down, one quick and easy one is the over centre clamp, a bit like half a Mole grip.
Another thought, are you sure about drilling 6mm, and then opening to 8mm; this only allows a 1mm cut on each of the 8mm bit's flutes.
You might have needed to do that with your previous bench drill, but you've got a good machine now, so maybe a smaller pilot hole and then the 8mm.
|Thread: Carbide insert holders|
Posted by old mart on 15/01/2020 20:43:00
Those codes don't make sense to me, as for as the insert designation charts go, there is nothing starting with Z. You could post us some pictures of them, if they are a proprietary insert, you are likely to be out of luck, unless you have the means to make your own holders for them.
Here you go
|Thread: Sent lathe back|
Posted by Neil Wyatt on 15/01/2020 16:56:14
Might be worth beefing up the base board as well, I forsee much flexing when milling otherwise.
The lathe itself is a nice wee machine,some nice articles on accessories by Terry Gorin about four/five years ago in Model Engineer's Workshop.
For a substantial solid baseboard, check out your local kitchen worktop fitter, or ebay for a slab of granite kitchen worktop.
Slow to drill, but OK with a diamond bit, and cuts fine with a dry-cutting diamond angle grinder disk in a hand circular saw, though you do need to make a hole size adaptor for the blade.
That's why you bought a lathe isn't it, for making little bits and bobs as well as models.
Depending on the accuracy you need, it should also allow for sliding a height gauge round the base when setting up/marking out.
|Thread: Myford super 7|
Posted by Steviegtr on 15/01/2020 00:14:36
Thanks for that. I have wired the e-stop to an input you can program. I have set it to cut the inverter instantly. But it only coasts to a stop. No d.c injection. I asked the question as to whether it was possible to make something to stop the chuck unscrewing. Someone said that some of the chucks had a grub screw to lock it on , but not sure exactly what was meant. Pretty good electrically as it was my career but the lathe. Just a learner.
Edited By Steviegtr on 15/01/2020 00:15:16
Personally I've never come across anything on a Super 7, but that doesn't mean to say no-one's done it.
A conventional grub screw doesn't seem a good move though as It would possibly throw the chuck off line with respect to the spindle register.
I do use mine for screw cutting in reverse, and have even used it for turning short tapers in reverse.
Some folks are prepared to risk it by just tightening the chuck well down on the register, but that doesn't really appeal.
I only had short workpieces to do, so I used a drawbar through the spindle with a knurled knob on the left hand end. My 4 jaw has a slightly smaller through hole in the backplate than through the throat in the chuck. I just added a washer and screwed it to the drawbar.
For the 3 jaw, there is a slight gap behind the chuck but in front of the backplate. That allowed be to use a washer with two sides guillotined off, and the edges thinned down, such that I could fit it in the gap without separating chuck from backplate; this again was screwed to a drawbar.
It worked fine for me, with no danger of the chuck rolling across the floor.
The reason for turning a taper on the back of the workpiece was thhat I'd already used a boring tool to turn an internal taper in a Quorn spindle, and wanted to make a batch of arbours with the topslide at the same setting.
Hence turn internal taper with a very small boring tool in the conventional manner, and then swap to a larger tool, and turn the external taper on the arbours with a bigger boring tool and the lathe running in reverse.
Conventionally, to turn the external tapers on the arbours, I would have had to hold the thinner end in the chuck and use normal turning tool, but doing it this way made it easier to cut the thinner diameter, turn down and thread the end of it, and also cut the taper without removing the workpiece from the chuck, hence maintaining concentricity.
Edited By peak4 on 15/01/2020 01:47:43
Depending on the inverter, it's possible to wire up an emergency stop as well as the switch that cuts the input power.
I'd investigate how it works for use on a lathe with a screw on chuck.
I've both a Myford and a Warco 1330, the latter having a D1-4 camlock, so it's safe to run in either direction.
The Warco also has a foot brake, which as well as tripping the motor, also stops the spindle dead.
One thing I have for the Warco is a spindle adaptor, so I can use Myford screw on chucks with the larger lathe.
For obvious reasons, I don't use the brake when I've got a Myford chuck on the Warco.
If need be, when using high speeds, put a wedge under the brake to stop it operating.
|Thread: Carbide insert holders|
Double check the sizes, but I guess something like this.
|Thread: Bottled Gas Suppliers|
Posted by Bazyle on 12/01/2020 20:50:07
The SGS site doesn't give prices "contact agent" minefield, so some prices from users would be interesting. There is an agent within 3 miles of me though. They sell propylene - is that hotter than propane? might help Dave above.
There's a reasonable precis at The Welder's Warehouse on that one.
|Thread: Welder Inrush Current|
Dave, I'll double check, but I think the D16 is a Schneider
Neil, I did think about that whilst I was typing up my original query. Why I never considered it before, I'll never know.
I do have a couple of long 2.5mm extensions, so I might re-purpose my 110v one of those to 16A connectors and see what that does. It's quite long so it might do; just a shame it would overheat if I left it on the reel.
Anything will have to wait a day or two though as I'm otherwise engaged tomorrow.
Posted by Ian McVickers on 12/01/2020 19:59:47
Try a D20. This will supply a higher inrush current.
Unfortunately, I don't think it's quite that simple.
A "C" curve nominally trips @ 5-10 times rated inrush current, whereas a "D" trips @ 10-20
Not happy about the idea of upping the house end of the garage supply to a higher rating, as there's then the danger of tripping the house board completely.
Hence my problem, that a D20 at the workshop end will trip at about the same current as the C40 at the house end.
I need the MCB equivalent of a slow blow fuse at the garage end's 16A supply.
|Thread: Bottled Gas Suppliers|
Depending of your application, you could try the glass bead artists method of heating stuff.
I've never tried oxy-acetylene welding, and for the amount I'd do, cant's justify renting/buying bottles.
I do occasionally want to heat things up a bit more locally than with a normal larger propane torch.
To that end, as I'd already got torches, flash arrestors etc, I picked up a second hand medical oxygen concentrator
OK it doesn't supply 100% pure oxygen, but works at over 90% @ 4 litres flow, and seems to work OK for me.
Mine came off Gumtree, but Tufnell Glass are one supplier; I've never used them myself.
Edited By peak4 on 12/01/2020 19:47:05
|Thread: Welder Inrush Current|
A general query about welders/transformers and MCBs in the workshop.
I have a stick welder which trips the MCB when powered up, I think due to the quick saturation/inrush current.
When we moved over to Buxton, I had a new garage/workshop built, with single phase supply fed off the house dis board via a suitable armoured cable. (Can't remember now, I think 10mm².) My builder is also a qualified sparky, and all wiring is correctly tested, recorded, and registered.
The house end of the cable is terminated in a C40 breaker in a spare non-ELCB position on the normal domestic board.
It terminates at the garage end on a new 12 way dis board with ELCB protection supplied at this end, so I don't trip anything in the house.
Amongst the facilities in there, I have a dedicated 16A socket to run a 110v transformer. Originally I bought an ex -WD 1.5 KW torroidal one, but the fast saturation was enough to trip a D16 breaker, I didn't want to go to anything higher as I don't want to trip the breaker in the house board.
I duly replaced it with a 2KW conventional transformer running off a C16 and all now OK with that side of things. The chap I bought the torroidal one off demonstrated it at his house; it ran fine off his D16, but it was much further away and a far older install. My cable runs are quite short and have good low impedance(s) all round.
I later picked up an older oil cooled stick welder, with the intention of running that off another dedicated 16Amp socket. The (different) seller ran it off an MCB, rather than a fuse, again I believe a D16, but said that he just needed to power it up initially at one end of the current adjustment, and then after the transformer had saturated, he could weld at all of the available ranges without a problem. He ran it in his other workshop via a fused outlet.
Unfortunately, at my workshop it trips a D16 breaker on power up. I'm again wary of going too high, as I don't want to risk tripping the C40 at the house end.
The 16Amp sockets are each fed with 2.5mm² twin and earth, radially to dedicated MCBs, so the cable should be good for 20A
I guess I could try a C20; I'm the only user working in there at the time, so wouldn't actually be welding simultaneously whilst running a 110v grinder etc.
I'm aware I'd have to consider the 3HP compressor kicking in whilst I'm welding.
I'm confident that the welder isn't actually faulty, as I've had a play with a megger, so I think it's purely a speed of saturation problem, with a large inrush current causing the tripping; I suspect it would be fine running off proper old fashioned 16A fuse wire.
I have a smaller 140A SIP stick welder, and a 140A Cebora MIG which work fine in the same workshop off a conventional 13A ring main fed from a B20
Does anyone have any useful suggestions please?
I know we have folks on here who actually do/did workshop/industrial electrics for a living, so experience is better than me studying the trip curves of various MCBs.
I also appreciate that it's not good for the MCBs to keep tripping them, so I've limited my experiments thus far.
I know you can get a slow starter for electric motors, but for welders???
|Thread: magic 127 TOOTH ?|
Broadly speaking, the length of the metre (meter) hasn't changed, unlike the inch, though the means of defining it has been updated over the years.
Perhaps the best explanation I've seen is HERE
Sorry to the folks over the pond, but it seems the US inch is actually metric.
|Thread: Magnetic chucks|
Posted by KWIL on 10/01/2020 15:56:20
! I think I will pass on that one, thanks for the offer to haggle.
There's a couple on ebay at the moment, one of which is in Hampshire, so maybe saving on the postage.
For small workpieces, I surround them with M12 thick repair washers; seem to hold well enough and with light cuts, things stay in place OK.
|Thread: Electric welder at Lidl|
Posted by Ian Parkin on 10/01/2020 17:40:40
Well those photos are of a plasma cutter
There's a couple of videos available showing the use of the item in the photo ( a couple are of the A1 model, rather than B2)
I guess I'll have to keep tabs on Lidl's website and see what arrives on the shelves.
Unfortunately since moving away from Sheffield, my nearest store is in Leek.
I'll have to think about whether I could use an un-welder.
|Thread: Magnetic chucks|
I guess it depends on cost really; there's a couple on ebay at the moment to give you a guide.
I have one on a Myford backplate and do use it occasionally, mainly for thinning or truing washers (or at least things that shape anyway).
Mine came a few years ago for £40.
I also bought a Meddings high speed drill, where the previous owner (a well respected model engineer) added a backplate to an imported one so it could be used as a table. Handy for making repeat parts, as the vice can easily be positioned and locked down with something else as a workpiece stop/locator. Say a 1-2-3 block with a threaded stud sticking out.
The genuine Eclipse one is thinner and has more holding power than the Chinese import one. I'd be very careful using the imported on on a lathe.
Edited By peak4 on 10/01/2020 12:27:42