Member postings for Ross Lloyd 1

Hi

I have a bunch of cheap lathe tools I got when I started and after buying a single, nice carbide turning tool, I realise how many of my problems were coming from the low quality cheap set of tools I had bought.

I am at the point of needing to do some parting and decided I would buy myself a nice new parting tool. Have you guys got recommendations on what to go for, especially users of the Warco WM250? Will be mostly mild steel I am cutting. As I am rather taken with my new carbide tipped turning tool I am leaning towards that for a parting tool too.

New or used is good, though if the latter any good suggestions on where to look for second hand gear? Best to get one with a holder or not? RDG have some holder type ones for about 45 quid, carbide / index.

Cheers!

Edited By Ross Lloyd 1 on 08/01/2019 17:09:23

Thanks all for the replies, I am going to try the "gradually move the work out of the chuck" method so there is added support first, as this seems most straightforward and Jason's results do seem to speak for themselves. I don't have that style of collet, I have ER32, any reason why the method may not work with that?

Cheers as usual, replies here are always 1st class

Hi

I need to machine a small diameter but large l/d ratio part. My first attempt lead to a bent part I watched some videos on youtube, and the suggestion seems to be to start with a large piece of rigid stock, and then turn the part in "one shot" avoiding multiple passes to size. Now, this seems to be a solution that works well for the experienced lads on their nice expensive professional lathes, but will this work for a beginner on a Warco WM250V?

The setup is as below. 12mm stock in a collet chuck. Turning the first diameter, if its to be in "one shot", is a 4mm depth of cut (12mm down to 4mm), and the second would be 2.5mm (12mm down to 7mm). The aim of this one shot approach is to avoid subsequent cuts that exert sideways pressure on the part and hence bend it. But I am far from convinced that a WM250V is going to have the grunt for a 4mm DOC or that the 4way tool post has anything like the rigidity needed.

I've seen others using a special small diameter turning tool with little support bushings and taking multiple passes. However I am working from the Workshop Practice Series Lathe book, and the author just suggests chucking an appropriate sized piece of material in a 3 jaw and going for it as you would any other piece. As I already saw bending with a collet chuck, I feel like I am missing something.

Do I actually need a special approach for such a part, and if so is a WM250V going to choke with that depth of cut? What kind of tool and speeds might be recommended? Alternately, is there some other way to do this without having to buy / make an accessory?

Here's the video I am going from, see 5:03 for the kind of cut we are talking:

I started a conversation with Joe there (user: TheDroidBay) but I am too much of a newb to understand the reply! 

Edited By Ross Lloyd 1 on 30/12/2018 00:44:42

Thanks all

I ended up kind of wishing I had a drill pad. His approach in the book would have made the subsequent operations much more straightfoward. That said I got to play with my mill a bit more which was nice, I just havent bought a vice yet so made life a bit harder for myself. Still, the part is looking ok so far, very rewarding experience.

Thanks again

Hi

I am working through the Workshop Practice Series, the one on lathework, and the author dropped this interesting bit of info. He suggests, in the absence of an alternate drilling option, to use a "drill pad" on the lathe cross-slide. However when I search google for a 'drill pad' (or alternatives like lathe drill clamp, lathe cross slide drill clamp, lathe drilling attachment), I see devices that are nothing like that shown in the picture:

**LINK**

Now, I have a milling machine I can drill the holes with, but I am intrigued by this. Is there some other name for it? Is it just a clamp of some kind? Or just a milling slide for a lathe with a parallel clamp to hold the piece?

Edited By Ross Lloyd 1 on 17/12/2018 13:58:58

Thanks all for the responses, a lot to chew on there. I went back and gave it another try and added some support from a dead centre, fiddled about with the tool angle and adjusted speeds and feeds and got some OK finishes. Certainly not mirror finish but I am just using a bog standard cheapo turning tool.

I will have a play around with the various shimming methods suggested and see if that helps. I've also come to the conclusion that one or two of my insert tools are wrecked.

Mark, what a good idea, thanks!

Title kind of says it, by how many millimetres / tenths / hundredths does your lathe tooltip need to be off exact centre before the turned finish starts to degrade?

At the moment I just have a piece aluminium sheet offcut to boost my tool height, and its probably off by about half a millimetre. My finish could definitely be better, so will better centring help? I have some shim on the way to try but I just want to get a feel for expected results!

Oh for one of those posh expensive QCTP's with the adjustable dial ....

Cheers!

Thanks gents nice to know nothing is wildly out of the ordinary

Thanks for the replies guys, on closer inspection it appears the mill just has an oil leak. I had assumed it was an open design due to the constant dripping, but when I filled it via the port and then looked up inside with a torch, I could see there is a thin ally panel that is screwed onto the sump and the oil is leaking around the side. I had a similar issue when the lathe was delivered, all the oil in the apron had leaked out of the drain plug. Looks like I will have to get up in there with some teflon tape as well.

Sigh warco, why do your machines have such a phobia of oil

Edited By Ross Lloyd 1 on 28/09/2018 12:48:04

Hi

Yesterday I was messing about learning to use an edge finder, so was not actually doing any cutting, but the spindle was doing around 1500 rpm. I noticed after about 6 or 7 minutes that the chuck felt warm despite no cutting taking place, and when I felt the body of the mill it was very warm to the touch from the drill chuck all the way to the top of the plastic motor cover.

Does this sound par for the course? With no load I would expect a smaller current draw and so less heat. There is a ton of oil inside the head, so much so that occasionally a little drips out on the table. It is an open design and you can just squirt the oil onto the gears.

The mill is a WM18, and I have had it since May. I had some electrical problems with it which were resolved with a new controller board, but given past performance I want to ensure this level of heat is to be expected.

Mill is finally fixed! Looks like it was a dodgy board, that somehow also cooked the main control pot that has a good 120VDC running through it. When I replaced the board the first time, something went bang presumably due to the now dodgy pot, leaving some choice scorch marks on the new board.

Warco kindly sent out a very helpful gent who changed the pot and the board, and the mill is now performing better than it did when new.

Have shown the pictures to an electrical engineer friend and when I mentioned the 180V likely to be in those tabs, he pointed out that the "swarf" may actually be tracking damage as the fault moved through the aluminium backing. The initiator then may have been the misaligned rubber strip, which was placed too low on the two thyristors. The plastic shoulder that insulates the screw from the tab had also partially melted.

Interesting info, thank you for sharing it. The board number in the Wm18 is JD-014, which appears to be the same one used by the grizzlys.

EDIT: Thats what's on the board at least. A sticker on the heat sink mounting plate reads "DC MOTOR SPEED CONTROL - Model: JYMC-220B-I"

Edited By Ross Lloyd 1 on 13/08/2018 21:48:23

Many thanks Dave, I will add that to the shopping list!

Cheers

Ross

Hi chaps, just an update. Spoke to warco today and they are sending out a replacement board tomorrow first thing It falls to the customer to replace 'simple' components like boards, so I have removed the board ahead of it arriving. Warco said I could keep the old one. If that doesn't work they will send someone out.

Here's the culprit. Looks like a few factory attempts at drilling went awry, and the swarf embedded itself in and made its way through the insulating tape (I checked and the tape is not electrically conductive, though may be thermally so. Top pic shows the mosfets in situ on left, note the insulating grommets keeping the bolts from touching the mosfet tab. Bottom shows the worn-through tape and chewed up drill holes after removing.

NOTE: Warco suggested I open the box to remove the board and said I could dispose of it.

May be worth checking if you own this or similar mill, especially if you don't have an RCD capable of tripping on earth leakage.

Hi John

If the board was ok, wouldn't you expect to see voltage at the motor terminals? When measuring across the screw terminals there was no voltage at all. As the terminals are connected directly to the controller, I would expect to at least see a voltage across them even if the motor was faulty?

Cheers

Ross

Thanks Nige, I thought it might be something along those lines. I am quite happy to replace myself, always good to learn what the insides of any machine are like.

Hi

Just wondering if anyone else has come across this? Ive had the mill only a few months (WM18 from Warco) and from the start it had a bit of a strange tendency to 'hunt', with sudden spikes in speed generally when you first turned it on and began to dial up to machining speed. I let it go for whatever reason.

I started it up today to do some drilling, and all of a sudden the effect was much worse, speed jumping up then down. It did this three times and then all the lights went out and the mill went off. It had tripped the earth leakage fault protection back in the house.

Now the mill does not work at all. The box powers up, I can hear the transformer running. I have checked all three fuses (plug and the two in the base of the control box), the blue light up display illuminates and the LCD works. The spindle and gearbox all turn freely.

After measuring with a multimeter, there is zero voltage on the motor (you can access the screw terminals to the brushes by taking a cover off) even with power on and rpms turned up, so it looks like something has shorted to earth inside the controller, given that it was the earth leakage trip that went and none of the other fuses blew in the mill.

Ahead of contacting Warco on Monday, any clues as to what might have gone and likely resolution? The mill is well within warranty. Do warco just send a new part or does someone come out to fix it?

Cheers

Ross

Unfortunately communication on this has gone dead so it is unlikely that they will be sold.