Search Results for 'zan'

[ZanParticipant @zan]

Tony.

Jeffree talks about changing the voltage which gave a lot more power. What are you running at. And what power does your psu put out?

Edited By Zan on 06/12/2019 16:44:31

[ZanParticipant @zan]

 

Nema 23 and 24 describes only the frame size and has nothing to do with its holding torque . some 23’s have 4.5 Nm while some 24 have only 1.65nm. So get the full details!

23 has a 56 dia flange, 24 has a 60

 

 Edit….. Another point is that if you use a step down pulley  say 2:1 to increase the torque it’s not that simple.  As the speed of a stepper increases, the fall off in torque is very dramatic, so you gain with the gear ratio, but loose on the motor torque itself! 

Edit 2   Just checked on the jeffree blog mentioned earlier, he used only a 1.8 mm type 23.   With a 40 v drive. I will go for something a little more powerful, a 3 or 4, as rthere is little price difference.

 

Edited By Zan on 06/12/2019 16:08:24

Edited By Zan on 06/12/2019 16:16:31

[John Parry 5Participant @johnparry5]

Thanks for the Idea and the Photos Zan. I do like the Student its a nice size. John

[ZanParticipant @zan]

The thin aluminium  guard came with the set from newall  the mounting at the fromnt is slotted for positioning, the small screw end on holds the end of the sensor bar, which is mounted only at the front .  The cover is held in place with small cks “cap” screwsSeems the angle bracket also carries the sensor , it can be seen in both photosSry about the delay went to buy a loco but unfortunately the wheels were loose….. shame, was exactly what I wanted

Edited By Zan on 03/12/2019 17:36:50

[SillyOldDufferModerator @sillyoldduffer]

Posted by Zan on 30/11/2019 21:58:59:

…

” I used a 1024-pules (4096 count) encoder (Omron E6B2-CWZ6C).
Choose an encoder that runs on 5VDC with open-collector outputs.

…

To add to Michael's answer, the CWZ6C is the NPN Open Collector version. If you want PNP Open Collector, buy the CWZ6B. (Can't think of a good reason for buying PNP as the PNP encoder has reduced performance.)

Open Collector is an output convention that expects the attached controller to hold its input line at logic HIGH. This is typically +5Vdc provided by a connecting a high value resistor (>1k) from the input pin to supply. An open collector encoder signals by pulling the input line down to logic LOW by shorting the computer's input pin to ground.

NPN and PNP switch in the opposite sense, thus NPN HIGH is PNP LOW and vice versa. The microcontroller can be programmed to work with either, but, if building a project with someone else's code, easier to follow their instructions!

The same encoder is available in a form that signals by outputting a positive voltage rather pulling the line down to zero. (CWZ3E). Again, the microcontroller can be programmed to work with this convention, but small code and circuit changes would be needed.

Similarly, the CWZ1X signals in RS-422A, which is designed to drive long twisted pair cable – an unnecessary complication in an ELS project.

All the models come in a range of different resolutions making it necessary the check the specification carefully before buying. The lowest is 60 pulses per revolution, the highest 2000. Look for mention on the label or sales literature first for the encoder ID, "E682-CWZ6C" and then find its pulse rate. This will be a number like 1000P/R, 1024P/R or 2000P/R and may not be immediately obvious. The encoder has several makers. I don't think it matters.

Datasheet here

Dave

 

 

Edited By SillyOldDuffer on 01/12/2019 13:07:19

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Roy Vaughn on 01/12/2019 00:05:34:

Michael, I'm not an expert either but clicking on the Ebay link in the encoder line item on the Clough42 web site takes me to something with what looks like an identical spec. Not worth ordering anything else and risking problems for the sake of a couple of weeks in my view. The big ticket item is the stepper motor and controller.

Zan, thanks for the link, looks like very comprehensive description of the mods. For reference in full (sorry I don't know how to make it clickable), it's:

http://www.jeffree.co.uk/pages/ml7-cnc/part-1-files/myfordcncpt1.htm

Roy

.

Cheers, Roy

Here’s your **LINK**

http://www.jeffree.co.uk/pages/ml7-cnc/part-1-files/myfordcncpt1.htm

MichaelG.

[Roy VaughnParticipant @royvaughn26060]

Michael, I'm not an expert either but clicking on the Ebay link in the encoder line item on the Clough42 web site takes me to something with what looks like an identical spec. Not worth ordering anything else and risking problems for the sake of a couple of weeks in my view. The big ticket item is the stepper motor and controller.

Zan, thanks for the link, looks like very comprehensive description of the mods. For reference in full (sorry I don't know how to make it clickable), it's:

http://www.jeffree.co.uk/pages/ml7-cnc/part-1-files/myfordcncpt1.htm

Roy

[ZanParticipant @zan]

That looks just the ticket! And Looking at the spec it looks ok to me, but I’m no expert

But the lead time is terrible it’s very similar to the ones I’m looking at, with 3 weeks projected delivery  but at the moment it can take 10 mins to load a page to view it and others. So I’m in no hurry at the moment.

Looks like the main bits will cost. the order of £100

Edited By Zan on 30/11/2019 22:46:56

[Michael GilliganParticipant @michaelgilligan61133]

Sorry, Zan … Clumsy arthritic old fingers

I’ve fixed the link now.

MichaelG.

[ZanParticipant @zan]

The encoders from U.K. seem to be expensive or lacking in data  information pre sale . I want one with a z output for syncing so it mabe a China hobby, but clough42 says I also can’t find a 1024 here, most are 600p/r

” I used a 1024-pules (4096 count) encoder (Omron E6B2-CWZ6C).
Choose an encoder that runs on 5VDC with open-collector outputs.

so does anybody know if this is an npn or pnp device? Or doesn’t it matter ?

The led n key board. Ebay.  Look for …….  

8 bit digital led tube tm1638 key display module for a real arduino te 289 ab.

Price £4.71. From Edinburgh 3 day delivery

Edited By Zan on 30/11/2019 22:07:13

[ZanParticipant @zan]

 

I will be mounting the motor at the tailstock end Drawings available from Jeffrey.co.uk. Just select the below n google it ……Im not sure doing the modification to the leadscrew bracket or putting the thrust bearings in will be really required as I intend to leave the gearbox in position. At some time in the distant future, the electronics may fail and all the units will be obsolete. I may buy a second processor and led&key board and program both when the whole system is up and running

Myford ML-7 lathe CNC conversion – Part 1: Leadscrew

 

david, any rotary encoder will only be fitted to a servo motor, otherwise the clough42 system is open loop if a stepper is used.  The encoder in the system is for synchronising the leadscrew and spindle, it’s mounted at the headstock

i am also considering adding a separate arduino system to stop the saddle ar two exact points, at the start an end of its movement and linked to the encoder z to give spindle sync.  This will be similar in principal to the meek and cleve leadscrew dog clutch system

 

Edited By Zan on 29/11/2019 09:48:19

Edited By Zan on 29/11/2019 10:02:54

[ZanParticipant @zan]

Pekkka, I had forgotten about that git hub list. Thanks!

Phil. That seems better than waiting from a China delivery for the encoder, but the one I have found on eBay is a bit light on specification

You can change the pulse count because clough42 gives the information in the video about getting the software he rings two important bits of data, the no of pulses and the tpi ( pitch in metric I seem to remember). Only viewed it once

Ah… there’s two postings unseen on this page!

just got got to get all the components before I really start

 

Edited By Zan on 28/11/2019 18:24:46

[PekkaNFParticipant @pekkanf]

Zan,

You may want to have look on GitHub Wiki component list: – lathe spesic parts

https://github.com/clough42/electronic-leadscrew/wiki/Stuff-You'll-Need

And watch episode Lathe Electronic Leadscrew Part 15

" I used a 1024-pules (4096 count) encoder (Omron E6B2-CWZ6C).
Choose an encoder that runs on 5VDC with open-collector outputs. "

[Roger ClarkParticipant @rogerclark]

Hi Zan, I've got a E6B2-CWZ6C from newworld-201 on Ebay, ordered on 11/11/19, arrived on 22/11/19 so good service from China. Haven't tested it yet .

[ZanParticipant @zan]

Time to get the encoder, but a couple of important questions…..

1). Does it need to be incremental or absolute

2). pnp, npn,  or open collector *2 output., which I think is best as it gives A and B with not A and Not B which I think will give the 4 times count so that a nominal 1000 pulse can be increased close to the cough42 ( 4092(?). The exact pulse count is set within the setup of the software

I will be ordering from China which has a long lead time, or the cost is at least 4 times greater

 

edit.. syntax

Edited By Zan on 27/11/2019 13:40:59

[ZanParticipant @zan]

Here’s my dead simple tailstock measuring device.

sorry it’s upside down.

Uses a simple terry clip, a bit of case binding steel strip as it’s springy and a 4 ba bolt with 3 nuts. Just file a notch and a point in the strip. The ruler enables both metric and imperial by just rotating the lot. Normally stored in the lathe tool drawer . I like to think the resolution is as good as I can mark out with a rule and scribing block, so very good!

one day I will machine a placement for a pair of pillars to get rid of the spring in the ruler .  I would love to find a ruler which is graduated from the right or even mount the plastic digital calliper I bought years ago but this solution is so simple and there’s more interesting things to do! The tape gets sticky and needles replacing every 3-4 years…..  in use just move the point to a suitable starting place and work to the depth you need.  So so simple, but nothing like the highly elegant solution Graham Meek will provide us with!

Edited By Zan on 25/11/2019 15:04:53

Edited By JasonB on 25/11/2019 15:06:04

[ZanParticipant @zan]

I have been following this thread with amusement. While the extent of the knowledge of some posters in many of the threads  is amazingly fantastic it just proves that at times advice can be contrary to just having a good look at all purchased kit just to see what the actual limitations of usage are, to check for problems and at the same time check its accuracy . My type 2 vice won’t be modified for a while as it is semi permanently mounted on a squared sub plate push fitted into to a central trough to give immediate positioning along or across the table as recommended by Marcus Bowman in his recent cnc book. The only reason to remove it will be for the rare use on its edge. The sub plate can get gouged as much as it wants without any problem.

Solutions are often so simple as has just been proven!

Edited By Zan on 25/11/2019 14:30:42

[ZanParticipant @zan]

As the owner of a 3” waggon I can say go for a 4”. I cannot leave my engine for more than 5-10 mins or the fire will die or water level will be too much or little. I get very jealous of the 4” wagons, where they can be left for a quite long period and even going to the bar to get a pint and the chip shop in one session without the danger of the above problems

trailer? Mine is 6’x 3’-6“ x 4’ high and is rammed full with kit , driving trolley, coal , tools , lighting up kit, dirty clothing etc. They are essential or you need a substantial van so that is not anything to consider

a lot of found components can be easily adapted for a 4”, diff, small car wheels etc. This depends on the level of accuracy you aspire towards.

3” in comparison are rather delicate and also it’s very difficult to clean in the cab as space is very very tight

 

edit…. in addition  you sit in a 4”, much more fun than sitting on the smaller 3”  go for . When I started building mine it was a big engine.  Now it’s the baby at almost all the rallies I go to

 

Edited By Zan on 22/11/2019 20:51:45

Edited By Zan on 22/11/2019 20:55:37

[Robin GrahamParticipant @robingraham42208]

Posted by Martin Kyte on 20/11/2019 11:38:23:

Posted by Robin Graham on 20/11/2019 00:52:37:

Thanks for replies. Looking at David's (impressive!) range of DIY boring tools, and taking Zan's advice that zero rake works OK I made a tool (from silver steel) with zero rake. My need was for a 12mm blind hole 15mm deep with a flat bottom – so it is pretty slender. But it worked!

I notice that my first cuts gave a slightly conical bore, with the narrow end towards the headstock. After taking numerous spring cuts I ended up with a parallel bore, but I don't understand this behaviour. How does the tool know where it is?

Robin

If there is not much clearence between the wall of the bore and the shank of the tool you get swarf build up which can 'spring' the tool in a little and reduce the cut. It will get worse the deeper the bore because there is more swarf about.

regards Martin

Thanks Martin – that makes sense. My insert tool holders have through coolant, I guess that's why I haven't noticed this phenomenon before. Should have thought of that – my one-track mind was too focused on tool geometry!

Robin

[Martin KyteParticipant @martinkyte99762]

Posted by Robin Graham on 20/11/2019 00:52:37:

Thanks for replies. Looking at David's (impressive!) range of DIY boring tools, and taking Zan's advice that zero rake works OK I made a tool (from silver steel) with zero rake. My need was for a 12mm blind hole 15mm deep with a flat bottom – so it is pretty slender. But it worked!

I notice that my first cuts gave a slightly conical bore, with the narrow end towards the headstock. After taking numerous spring cuts I ended up with a parallel bore, but I don't understand this behaviour. How does the tool know where it is?

Robin

If there is not much clearence between the wall of the bore and the shank of the tool you get swarf build up which can 'spring' the tool in a little and reduce the cut. It will get worse the deeper the bore because there is more swarf about.

regards Martin

[Robin GrahamParticipant @robingraham42208]

Thanks for replies. Looking at David's (impressive!) range of DIY boring tools, and taking Zan's advice that zero rake works OK I made a tool (from silver steel) with zero rake. My need was for a 12mm blind hole 15mm deep with a flat bottom – so it is pretty slender. But it worked!

I notice that my first cuts gave a slightly conical bore, with the narrow end towards the headstock. After taking numerous spring cuts I ended up with a parallel bore, but I don't understand this behaviour. How does the tool know where it is?

Robin

[dcostaParticipant @dcosta]

Hello Phil,

I agree with Zan. Please do so.

Dias Costa

[Phil GrantParticipant @philgrant54580]

Posted by Zan on 18/11/2019 19:27:21:

Hi phil

Thanks , goods received. Looks good

Edited By Zan on 18/11/2019 19:30:55

Glad they arrived OK.

Little Top hats to sit on the buttons are a good idea, the natural spring back of the switch will be enough, I don't think you'll need any springs or foam.

Phil

[egaParticipant @ega]

Zan:

Good tip about the penny washers!

[ZanParticipant @zan]

Inserted tools tend to be mounted high with the tip angled down enabling a larger dia bar or the ability to be used in a smaller bore. Same difference. In addition, the tips have small rake angles seen easily by examining one. This means they would foul the bore unless it was very large. Without this they would be very delicate.

Hss tools cut differently and can have a little  rake, Too much will weaken the tool but they can also be set a little above centre height to enable better clearance, which unlike an external tool will improve things

in addition some think it is just a matter of dropping the height of the bar then rotating it upwards to put the tool back on centre height. This is a recipe fir disaster as the tool again will foul

i use a set of penny washers, bored at 3 then 5 mm intervals up to 30 mm . Each has a line scribed by the tool across it to indicate the centre line. It’s then very easy to see which tool will be suitable for a particular bore before it goes onto the machine the clearance of the tool or lack of it will be obvious

hss tools will bore quite well without any top rake

 

oops typos

Edited By Zan on 18/11/2019 23:50:16