Member postings for GoCreate

Andrew, is your refractometer something like this one?

**LINK**

Thanks

Nige

Hi

What does the abbreviation ELS stand for?

Brilliant work!

Thanks

Nige

Edited By tractionengine42 on 16/12/2017 10:54:58

Hi Graeme W

There is no mixing nozzle as such, the coolant simply drips into the air flow. The original block that came with the mist coolant effectively becomes a tee block, it's not necessary to start with a mist coolant.(I bought the mist coolant because it had the regulating valve at a very economical cost, but in the end that valve was ineffective).

All the tubing is all 4 mm o/d, the outlet nozzle is 4 mm o/d brass tube.

I have attached a rough schematic below. I considered a few much more elaborate arrangements, this very simple arrangement is working very much to my satisfaction, I wanted to have a very low coolant consumption, just enough to lubricate the cutter.

Hope this helps and good luck with your set up.

Nige

Edit - The coolant exits the brass tube nozzle in droplets with no misting. 

Edited By tractionengine42 on 13/12/2017 10:55:21

Hi.

Converted a cheap mist coolant system into a 'mist busting' pressurised system for my cnc mill.

I used a water supply filter casing as the pressurised coolant tank, so far it's works very well, the coolant flow can be adjusted from zero to a dribble (and faster). It was necessary to add an additional regulating valve in the coolant supply line, the regulating valve supplied with the standard mist coolant assembly didn't work very well.

The photo below shows the set up, the centre outlet from the tank supplies the coolant to the nozzle and the far right connection the air to the nozzle. It's not necessary to have a water trap on the inlet regulator, it's just what I had to hand. The top connection on the nozzle assembly is the coolant supply.

Nige

Hi Micheal W, cutting that vee shape was an opportunity to use my Elliott Omnimill using a vee shaped cutter in the horizontal spindle arbour. So that cutter that came with the mill has found at least one use.

Nige

Edited By tractionengine42 on 28/11/2017 22:49:03

Hi Jamie

I've sent you a PM.

Nige

Hi

Today I completed this tool which I believe is called a finger plate. No drawings just based upon what I can remember seeing from time to time.

I wanted a quick simple project with some nice milling and turning. This is a tool I have wanted for some time to help hold small parts for drilling and linishing etc. I think it should be useful.

A cross drilling feature is included with 2 aluminium bronze bushes to suit 2 sizes of spot drills I use, 3mm @ 5mm.

All materials from the scrap box and sizes determined by the size of the piece I used for the base block about 3" x 4". I think these tools are usually made much smaller.

Nige

Hi

Soaking it in penetrating/release oil a few hours may help.

Nige

Hi

Tools using inserts with a plain straight hole don't use screws for clamping, they have an internal and/or external clamp arrangement where a screw acts on a lever and the lever clamps the insert.

I would imagine the leading manufactures will have some information on their websites.

Nige

Edited By tractionengine42 on 18/09/2017 16:13:50

Hi

I think the idea is that you take a number of incremental cuts. After taking the first cut the cam blank should be rotated a few degrees and a second cut taken, then repeated for a third cut, forth cut and so on untill the full cam profile is complete. This will leave the cam with a number of facets which will need to be blended using a file, emery paper and or stone.

Your first cam looks right for the first cut, it needs setting up in the fixture again and several more cuts rotating the cam on the fixture a few degrees each time.

Nige

As a Northumbrian a part that is within a Midgy's nif naf is good enough most of the time.

Hi Andrew

You can download an o ring guide here **LINK**

You can determine the pressure that the seal has to take by Jack max load / piston area.

The clearance between the piston and cylinder is termed the extrusion gap, this should be within specified limits for the seal to function reliably. If the extrusion gap is to big for the pressure applied the seal could extrude through the gap. My guess is your application is low pressure though.

A quality 70 shore hardness o ring will easily take more more than 1000 psi. Backup rings are used for higher pressures, these effectively increase resistance to seal extrusion.

I think using an o ring will provide a much safer and reliable jack. If the cylinder is steel then a bronze piston would be preferable. The finish on the cylinder bore needs to be a smooth finish with no scoring.

Nige

PS presumably you will need to put a seal between a metal piston and the piston rod.

Edited By tractionengine42 on 14/09/2017 07:24:07

Hi

There's some very good videos concerning Chinese laser engravers/cutters on this channel, very comprehensive and informative, well worth a look.

https://www.youtube.com/user/SarbarMultimedia

https://www.youtube.com/user/SarbarMultimedia

Nige

Edited By tractionengine42 on 05/09/2017 12:26:49

Hi

I believe you can use most bench grinders, you need to select pigtails that match the grinder shaft dia, usually 1/2" on small grinders and mop diameter/width that match the grinder power rating.

You can find recommendations for mop sizes relative to the grinder power rating here. I've no connection other than being a customer.

Nigel

Hi Robin

You could make a steel shank and silver solder a piece of 2.5mm HSS or carbide drill shank to it. If your going deeper than 1.25mm then grind some side clearance.

Some HSS drills do have a soft shank though, so a good quality drill will be needed. The temperature of silver soldering HSS won't effect the HSS hardness much.

As illustrated below.

Nigel

Hi

The electrical noise problem appears to be solved!

I had been running everything from the same socket via a multi point extension cable. After plugging the motor controller into a separate socket (still on the ring same ring main) everything is working fine. just spend an hour doing engraving with the high speed head and no problems at all.

So today is a good day and very happy with my new CNC mill build, fingers crossed trouble free running continues.

I will still make improvements by adding suppression filters etc. to be on the safe side.

So the lesson is don't run VFD's etc from the same electrical socket as sensitive electronic equipment. Allot of lessons learnt here about electrical noise and suppression.

Thanks again for your thoughts and suggestions.

Cheers, Nigel

Hi

Thanks again for your help and suggestions.

David - I have the standard (low speed) head and a high speed head, both ramp up and down on stop and start.

Martin - My control system is close to the motor so this may not have been a good idea. The photo below shows the set up for both low and high speed spindles. The cable to the high speed motor is shielded but not to the low speed motor.

​

I have ordered suppression filters and shielded USB cable.

Originally I ran the high speed motor a few times off the machine away from the control box with no problems but that seems to have been luck.

The current situation is that the UC300 almost always disconnects when either the high speed head or low speed head starts otherwise it will disconnect when the motor stops.

I tried starting the UC300 and Mach 3 with the motors already running, the system ran g code for a short while then the UC300 disconnected. On a couple of occasions the UC300 disconnected with the system running idle (no motors or gcode running).

I removed the UC300 from the control box and placed it 4 feet away from the motors (which meant running a long DB25 cable (shielded) between the UC300 and breakout board in the control box. The results were exactly the same, the UC300 disconnected when the motors start and/or stop. This being the case I'm not sure moving the whole control unit away from the mill will help.

As Said I am waiting for some suppression filters and shielded USB cables to arrive. Adding a powered USB hub has been suggested to remove any possible USB power supply problems.

I think I could spend my hours and GBP chasing my tail, I'm wondering if I should ditch the (expensive) UC300 and just use the computer printer port (I did this before when converting a Sherline mill to CNC and rarely had any problems). The other option is to go with the dedicated cnc controllers now available where no marrying of computers, software and controllers is necessary, I do like Mach 3 though.

Again any thoughts or suggestions appreciated.

Cheers, Nigel

Thanks Gents for your thoughts and ideas, I have very little electrical knowledge so suggestions are a great help.

The problem occurs only and precisely when I stop and start the motor which at present I am doing manually, not via Mach 3.

OK, as a first attempt to solve the problem I will use a separate independent power supply to the UC300 controller. I also like the idea of adding a snubber across the relay contacts. (I did wonder if it would be worth changing the stop/start relay for a solid state device, this could be a bit of a challenge for me though).

I like the idea of including a USB opto isolator, but as these seem quite expensive I will try the above first. As it will do no harm and is of low cost I will also add an EMI filter to the motor controller supply and use a shielded USB cable.

BTW, I have a separate high speed head using a different motor and motor controller. I've just been trying this one out and so far have had no issues. So that's encouraging.

Much appreciated, I will let you know how I get on.

Cheers, Nigel

Edit - BTW the drivers for the UC300 are up to date.

Edited By tractionengine42 on 21/04/2017 22:53:18

Edited By tractionengine42 on 21/04/2017 20:13:58

Hi Steve

I don't think squirting oil though the annular gap mentioned would be very effective in getting the oil where it's needed. Chain saw oil is tacky, this could be used on assembly and should keep the surfaces wetted, then don't worry about it, re-lubricate once a year or so.

I will be using chainsaw oil on my main exposed drive gears, because it's tacky it shouldn't fling around to much or run off to quickly.

Nigel