Member postings for Nick Taylor 2

Indeed. The OP has been incredibly lucky, and had he not been so fortunate the only person to blame would of been himself.

I bought the 0-6 inch micrometer set a few months ago from allendale, approx £160 from memory. I compared them to the top of the range mitutoyo set our mechanical engineer has at work and they all read to within 2/10ths of a thou of each other, very impressed!

I doubt they’ll last 20 years like the mitutoyos but for the ‘home gamer’ I’m sure they’re better than I’ll ever need. I’ve cut to very close tolerances using them and they feel nice to use as well.

They’ve been repeating Scrapheap Challenge recently and I noticed one of the team using a rather tidy looking Myford 254s - not exactly the machine you would think to find on a scrap yard!

I personally used the RDG '20mm' variant, named so as it takes upto 20mm tools. They are better than half the price other brands are work fine for me. You can feel how well they sit on the toolpost when you tighten the cam up.

I would stay away from cheaper 16mm holders - I bought some and you can nearly mark them with your fingernail.

https://www.ebay.co.uk/itm/RDG-TOOLS-T1-HOLDER-20MM-CAPACITY-QUICKCHANGE-TOOLPOST-QUICK-CHANGE-ENGINEERING/371551492707?epid=1157895265&hash=item568231da63:g:U20AAOSwq7JT5N5V

Nick

Another vote for the RDG 'Dickson' tool posts. I use the T1 size on my Chipmaster and have a mixture of original Colchester and new RDG holders and they all fit the Colchester branded Dickson perfectly.

As well as a quick change tool post I would say that a quick change gearbox is also a huge leap forward in usability. Utterly necessary? No of course not, but they mean less time faffing and more time actually enjoying my hobby.

The Dickson design is used with 20hp behind it so I doubt it's going to be a problem for us 'home gamers'. I have the original Colchester tool post on my Chipmaster, that's only 3hp but I've been taking some stonking big cuts in some en19 using the cheap (£22) holders from RDG and it works great.

I also have a wedge style Aloris copy on my super 7 (from arc) and that has really surprised me, it's the small 000 version but is still more than rigid enough. It is as small as I would go on the Myford though.

I think someone worded it very well when they said that the multifix posts were of higher general quality because the design needed high accuracy for it to work at all. They look great but the cost just isn't worth it in my opinion.

Edited By Nick Taylor 2 on 02/09/2017 19:17:51

From your pictures the nut looks exactly like the type fitted to my Chipmaster. I have never removed the screw so can't be 100% but it certinatly appears to be a Chipmaster part

Edit - unfortunately the Colchester yahoo group has been dead for some time, I'm not sure where else to reccomend.

Edited By Nick Taylor 2 on 23/08/2017 14:52:06

2155 would seem to point to it being a metric crossflide feedscrew for a Chipmaster, at least according to my manual. It should be complete with nut. If only it was imperial I would make you an offer!

I've bought 3 from RDG in T1 size last month for the genuine Colchester 3 sided post on my Chipmaster and they all fit perfectly on all 3 positions, could be luck I suppose but not bad for £22.50! The screws aren't as soft as usual either!

Hi Richard - great that you have found the problem!

I'm in the market for something VMC-sized at the moment. Have yet to see any info on the VFD equipped VMCs so will be interested to hear how you get on with it!

Cheers,

Nick

Hi Richard - if it does have a VFD then it's a new model of VMC (not even on the web site yet!), I'm not sure you'll find many people with the same version as yours. The fact that the VMC didn't have any electronics to go wrong has actually been a selling point, especially when you compare it to all the problems people have with the DC motors and speed controllers.

If you could get a picture or the model number of the VFD I'm sure a full manual will be available somewhere. It does sound like an earth leakage fault rather than an over-current fault. This is very common with the cheaper chinese VFDs.

On other forums (mainly DIY CNC forums where lots of the chinese 400hz VFDs are used) people check for this by running the VFD without an earth on the AC input side, obviously you earth the machine independantly for saftey - to be honest Richard unless you are experienced with machine tool electronics I wouldn't try this.

100 thou (0.2 inch from diameter) indeed, sorry that was badly written!

Been having a bit more of a play today and havent seen the motor pull more than 5 amps.

The WNMGs seem to generate very high forces, when I pushed the DOC to 125 thou I got a little chatter thanks to the bell mouthed jaws on the chuck I am using but I am sure they take a lot more from the machine than say a CCMT style neutal/positive insert.

The negative rake on the WNMG is massive and while they do give a nice finish and seem to be able to remove a lot of metal I think when I tool up this lathe I will stick with CCMT style inserts as the minimum DOC on the WNMGs is very high. I use 10mm CCMT tools on the myford so will probably buy some 16mm shank CCMT tools so I can use the same tips on both machines.

Edited By Nick Taylor 2 on 29/07/2017 18:08:02

Well the machine has been in the shop almost a week now, have been cleaning up, getting it mounted properly and have changed all the oils (variator, gearbox, headstock etc).

Re-wired the existing 3HP motor from star to delta, entered the motor settings (max Amps, poles and RPM etc) into the VFD and it fired up first time!

Nice and quiet and pulls 2.5A at full speed idle (running spindle and gearbox etc but with no cutting). I was enjoying being able to see the current draw on the front of the VFD so I found some EN8 1 inch bar, stuck it in the chuck and made some VERY blue chips for the first time on the new machine!

0.100 thou DOC, 8 thou/rev feed at about 1200RPM using a WNMG insert and the motor was pulling 4A, so still plenty of power to use! Doubt I'll ever need it.

That's exactly the kind of setup I would like to go for, a 4mm2 circuit for the machines/VFDs then a 2.5mm2 ring for secondary single phase things like coolant pumps/radio etc all on a decent standalone feed. Once I have the money in order it will be on my list.

Cheers

Edited By Nick Taylor 2 on 21/07/2017 15:24:42

Out of interest while I had the VFD in work (that's where I got it delivered) I took advantage of an empty EMC lab and powered it up on our conducted emmisions kit. Obviously I had no motor to use on it but I wanted to get an idea of the power and earth leakage overheads.

Initial power up rush current was lowish (less than an amp), however it did pulse approx 15mA down the earth, so on an already busy ring that maybe an issue. Standby current was just under half an amp, so our idea of 90% efficiency might not to too far off.

Edited By Nick Taylor 2 on 20/07/2017 21:42:01

Well I took the plunge and my 2.2kw Huan Yang turned up today! I've tried it quickly with the 1/2hp motor on my super7 and I'm impressed, very low electrical noise compared to my older Mitsubishi which I usually use on the Myford.

The manual isn't as bad as I feared actually, however I do deal with translated data sheets etc at work so maybe I'm immune! What I like about it from the looks of the manual is that the hardware input functions can be changed so you're not tied to the factory setup.

Anyway the machine it is meant for arrives over the weekend (1970s Chipmaster), so I'll be able to get stuck into the config then. I hope to use the lathe's existing Rev/stop/fwd lever l (including the light up handle) as well as the e-stop peddle!

Hi Neil,

That's exactly my point - when we talk about a 2.2kw motor we are obviously talking about the three phase power output of the VFD, which bares little relation to the single phase input current requirment. My question in this thread was to see people's real world experience with running larger motors.

A few of the 2.2kw output inverters I've looked at today quote an input requirement of 40+ amps, granted that is peak, but still not something I would want to run off a bit of flex from a 13amp socket!

Still very tempted to follow Steve and go for a 2.2kw Huan Yang - the cost is hard to ignore!

Cheers,

Hi all, thanks for all the replies!

I'm no idiot and won't be trying to run a pair of 3hp motors off a single socket or anything like that!

Judging from people's experiences and reading as many VFD data sheets as I can it seems 1.5kw output is a sensible limit. Sure, a 2.2kw motor may start and run off load, but I bet it would blow a fuse or two with a heavy cut on.

The spur was installed by the previous owners and seems to be in good safe order, the cable is 4mm and protected by a 13amp fuse at the spur on the ring then each circuit in the garage is fused individually.

Hi Steve, great info - thanks. I was actually looking at the Huan Yang VFDs on ebay, they seem to have a lot more sellers with EU/UK stock now. At under £100 for the 3HP version I am very tempted. Have you had any problems with yours?

Running a better feed to the garage is in the plan, but budget wise it's probably not going to happen until some time next year.

Morning all, it's been a couple of hours since I asked my last stupid question so I thought I better think up another one so people don't think I've been abducted or something.

So... VFD's on 13amp sockets. Running 1/2hp at the moment for the myford with no problems what so ever. I only have a 13amp spur to feed my workshop, not usually a problem as I only use one low power machine at a time, however;

Now I am looking at larger machines that have 2hp and 3hp motors I obviously have a problem as a lot of 2hp or higher VFDs quote a max input current of 16+ amps. Now on other forums you hear of people claiming to run a 3hp machine though a VFD on a standard ring main for years and it has never blown a fuse etc.

But I would like to hear your real world experiences of running larger motors on domestic electrics. I know there is the option of single phase but I think that may be my last option. Just after actually spending some cash and getting the garage rewired. That option is just after winning the lottery.

Many thanks,

Nick