Here is a list of all the postings Steve Withnell has made in our forums. Click on a thread name to jump to the thread.
|Thread: Where have all the Mondeo's gone|
And he only had one house - how times change!
|Thread: Help choosing a smartphone|
Just been through this myself. I've seperated the problem into two parts - the phone and the service contract. Three are charging me £12 a month for 12GB of data + unlimited text and calls. So stopped using the house phone for outbound calls. See how much you spend on outbound calls to get the overall cost difference. I 've had the phone for a couple months or so and no matter how hard I use the phone, I haven't managed to use 5GB in a month, so 12GB is equivalent to "unlimited" in my case!
Next problem is then the phone itself. Samsung are fantastic phones, my wife has had them for along time. However, the latest Samsung is £750!!! Not happening. We now have three different Motorola phones in the family and all are good. They are built by Lenovo who have a good reputation. Two of the three were bought as special offers from Carphone Warehouse, service is great and they are easy to deal with. The third was bought from an online outfit offering the phone Moto X4 as the sharpest price, but rapidly turned into a nightmare which took weeks to sort out.
Reading your post, sounds like the X4 (with its 3 cameras and all metal case) is too big and heavy - albeit fantastic value for money. Take a look at a Motorola G5Plus, still big but lighter and it will give you a starting point. It's the right sort of processor and memory capacity to provide at least say 3 years usage before obsolence kills it.
|Thread: When is 9mm not 9mm?|
Another combination to watch for is 1/4" and 6mm in brass and copper round bars. The last two suppliers I've used off eBay don't differentiate between the two sizes...When I asked why they had shipped 1/4inch instead of 6mm, it was because they had 1/4inch in stock...
|Thread: Private Messages|
Mystery solved! I thought my account had been hacked when all these PM's started turning up...
Happy New Year!
|Thread: Myford ML10 headstock bearing play|
The runout on my first lathe was nearly 0.1" and would still make perfectly good parts! Really bad runout will still deliver round parts From a novice point of view (which I will always be at this game), knowing how your machines perform is more important than seeking perfection (which you will never achieve) in them.
Don't buy a collet chuck to make the runout go away - most turned parts are produced in either a 3 or 4 jaw chuck with only a few specialist jobs needing a collet chuck. I have all three - but 75% of jobs are done in the three jaw. 20% are maybe done in the 4-Jaw. A few are done on the face plate. Doesn't leave a lot of jobs that NEED a collet chuck.
I'm definitely with Jim and Hopper on this one.
A more important check might be to see if it is actually turning parallel, rather than taper and work on reducing any taper. This is easy to do - just stick 100mm of 25mm steel bar in the chuck and take a light skim over it's length and see it the start and end diameters are the same. If not - someone in the group who knows the ML10 better than me will advise next steps!
Happy New Year
|Thread: Using a fly cutter|
My first lesson using a flycutter was that the typical ones sold on eBay don't have anywhere near enough rigidity or mass for anything only the lightest of work. I 'made' one one by bolting 25mm square bar (with a piece of 10mm silver steel as a cutter) to the 250mm face plate on my lathe and used that to face off some large chunks off ally. I don't think the finish would have been as good on the mill.
|Thread: What's the strangest project you've ever seen in an old ME or MEW?|
Pretty sure the old Field Marshall was a 12 bore sized cartridge...Dad had one for a short time, think it went for scrap!
|Thread: Which lathe|
Get a C3 and start turning! My critieria for my lathe was it had to be the heaviest I could find that would fit on the bench and be new Chinese. Makes perfectly good stuff. Mind you, I don't get tool room jobs from NASA that often
Crazy decision making criteria, but no regrets at all and it's done a quite few jobs now over the ten years I've had it.
|Thread: Metalworking files - Guidance required please|
I wouldn't buy a set to be honest. I do have a set and pretty much 95% of the time just use the flat No.2. I don't think I've ever used the rat tail. An exception is the CK branded needle files, I use most of them, though again, the round file doesn't get used much.
|Thread: Lathe unwanted taper|
Bit of a tangent - when I was a kid 10 or 11, Grandad asked me if I had a testube I didn't want. I gave him one to make a level - he knocked a hole in the end of the tube and fastened it to a long length of hose pipe. By filling the pipe at one end until water appeared in the test tube he could establish a level over a long distance.
|Thread: How long does it take you to make stuff?|
Years, but I get there in the end...
The very best work I've seen is about infinite patience and the worst was rushed. So long as you are enjoying the process, how long it takes doesn't really matter?
|Thread: Spurious Accuracy|
Oh well, I'd better ditch my '10ths' clock then...
|Thread: Which milling cutters first?|
One answer would be "Milling: A Complete Course", by Harold Hall. 10mm end mills would get you started quite nicely.
|Thread: Milling - How to get a good finishing cut?|
Cheers Marcus. I've been asked to make another one of these, so I'll work out the machining as above. I've seen a few single flute cutters around from China, but may stick to a decent slot drill. My mill is flat out at 2,000, so will have to make do at that too!
All done - next step is to see if it performs!. I ended up polishing the sides with the flat of a file, I still had some noticeable ripples in the walls. More practice is probably in order.
My technique is to machine out the cavity a little too deep than skim the top to size, so the bottom of the cavity is parallel to the top of the walls. I could machine a through slot, but I'd still be left with the key issue of getting a nice finish to the side walls and I'd have 16 holes to drill and tap rather than 8 and two lids to make! So all trade offs as ever.
Edited By Steve Withnell on 27/10/2017 18:58:14
Interdigital Digita Filters - I've made a few at 1.3GHz and this is the first I've attempted for 3.4GHz. I thought with less metal to remove it would be easier, but I've also a lot less 'elbow room' with this one. I shall break out some turps! (I've been working with Parafin and Neatcut, but the Neatcut ends up in sticky mess).
I keep avoiding sending Ketan a wedge for a KX1, which would be ideal for this application The 22mm is not critical because the resonators are tunable. The depth of the case affects the impedance and bandwidth of the filter (etc). The cleaner the finish the better the overall performance.
I've milled a cavity in some Aluminium plate 22mm wide x 56mm long and 15mm deep. The corner radius is 2mm. I need to take a couple of finishing cuts, whats the best technique to get very best finish? Clue - 22mm is a quarter wavelength
I've obviously got a long series 4mm cutter, which is a standard helix carbide type and the only other cutter I have is a 5mm high helix version (which would obviously leave a bit of cleaning up for the corner radius. The depth of the cavity is the critical dimension.
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