Denford Triac VMC with ATC Conversion / Fix

[i2i]

for a stepper fitted machine, that has 400 steps per rev, and the gear reduction is 2.5:1, with the 5mm pitch you get 200 steps per unit in metric. For a 2:1 gear reduction it should be 160 steps per unit. All you have to do now is equate that to the steps per rev your motor has.

steps per rev / ( ballscrew pitch/gear reduction ) = steps per unit

If you have a bit of backlash check the angular contact bearings at the pulley end of each ballscrew, they may need adjusting.

Ps. don't forget to fold the tab washer flat to adjust the nut.

[Chaz]

for a stepper fitted machine, that has 400 steps per rev, and the gear reduction is 2.5:1, with the 5mm pitch you get 200 steps per unit in metric. For a 2:1 gear reduction it should be 160 steps per unit. All you have to do now is equate that to the steps per rev your motor has.

steps per rev / ( ballscrew pitch/gear reduction ) = steps per unit

If you have a bit of backlash check the angular contact bearings at the pulley end of each ballscrew, they may need adjusting.

Ps. don't forget to fold the tab washer flat to adjust the nut.

Thanks, so based on my pulleys being 12 / 24 (motor end / ballscrew end), 5mm screws, using 725 steps for damn near 100% accuracy, what do you believe the steps per rev is on the current IRT 1306 drives via the simulated encoder outputs?

[Chaz]

I have a favour to ask, not sure if anyone can help or suggest someone that can.

I bought a replacement drive from a vendor. Before I bought the drive, I asked if it can work with my current CS Labs and Mach 3 setup. I was told that it would.

Once the drive was installed, it was apparent that it would not work, not unless additional electronics was added as it does not output a suitable differential encoder output.

I attempted to get the drive refunded. The seller rejected this. Eventually he agreed that the drive doesnt work as I need and offered a partial refund. This was then upped later but not 100% as I requested.

Distance selling rules allow me to return the device however as this was a seller from EU (Finland), there is a clause that states that I can return only if the device / item has not been used.

I ended up raising a dispute with Paypal and forwarded them all the email correspondence that highlights that the vendor has accepted that the drive cannot output differential encoder outputs as needed (without building some custom circuitry).

Paypal have now come back and asked that I make contact with 'an expert' who can verify this. This is their request.

"Please obtain a document from an unbiased third-party, such as a dealer, repair shop, appraiser, or another individual or organisation that's qualified in the area of the item in question (other than yourself), which details the extent of the damage or clearly explains how the item received significantly differs from the item that was advertised.

This document must be on a letterhead that includes the name, address, and phone number of the individual, business, or organisation so that we may contact them if necessary."

I spoke to them at length this morning as I dont think this is reasonable. Why should someone, who has no role in this, assist me (at their cost and time).

I told them that the emails confirm what the seller had indicated. I was then told that emails could be altered. They offered a new option which was even more complex.

So, my question is, is there anyone that is either on this site or falls under the category of 'unbiased third party etc' that is willing to look at the info and put something in a letter than I can send to Paypal for the refund?

If not, Ill reluctantly accept the part refund offer that I had and cut my losses on this.

Thanks

[Chaz]

Looking at his email, it looks like he left it up to you to read through the specification sheet to see if it will work or not.
Looking at the details on the encoder output, this is very poor and not even a connector accessible form the outside of the box, so will require going into the driver and connecting to the ABZ, but this is only 3.3V and also very unacceptable to esd and electrical noise.
If is was just a single ended encoder output with a good 5V signal and a connector on the outside of the box, then this would not be a problem, by connecting a standard board to convert from single ended to differential.
If you want me to put something on paper i can do.
It makes absolutely no sense to have a good driver like this being limited by no differential encoder output.

Thanks. Agreed. I like the drive, its nice kit. I love the open source idea but its not what I needed.
It feels like I bought a car with an Aircon and then when it doesn't work, I get told to have some pipes and gas installed to make it work.

Appreciate if you can draft something up for me and sent it across.

Many thanks.

[Gary]

emailed you back.

[Chaz]

emailed you back.

Thanks, appreciated.

[Chaz]

Quick update time.

Machine is running but I need to do more tweaking. Need to recheck the PID control but generally fairly happy. Taken most of the backlash out both mechanically and with Mach 3.

Needed to move the mill but no method available. The engine hoist I bought isnt wide enough. Got an idea to buy some heavy duty castor wheels. Tried to fit them but the metal I wanted to put them on was too flimsy. Came up with a good plan, had some 20mm Alu plate for something else but milled myself 4 plates to basically mate the wheels to the load bearing beams, using the original shafts.

Some pics below, the CNC has now been moved to the location I wanted it in the garage. Last pic is of a new X plate but I ended up having a problem with it, so it wont be used.

[Chaz]

I wanted to thank a few people that have made this conversion possible. Its not 100% complete but mostly there. Still need to get ATC working and build a new control panel.

JazzCNC
i2i
Gary from Zapp (please support him)

There have been others too but I would not have completed this conversion without their help.

Many thanks.

[robertpearce4]

Hi Chaz,

I have just acquired 1/2 of a TRIAC VMC today so will follow your threads with interest. The Miller was going for scrap. Unfortunately I don't have the controller or a schematic but do have the monitor/PC, not that I think it of much use on its own. I have to decide if the miller is worth the time of effort to "upgrade". Even with the latest electronics/controllers its not as simple as plug and play. I agree its heavier than it looks. The C of G is not where you expect it either. The lifting eye on the top gives the game away.

[m_c]

Hi Chaz,

I have just acquired 1/2 of a TRIAC VMC today so will follow your threads with interest. The Miller was going for scrap. Unfortunately I don't have the controller or a schematic but do have the monitor/PC, not that I think it of much use on its own. I have to decide if the miller is worth the time of effort to "upgrade". Even with the latest electronics/controllers its not as simple as plug and play. I agree its heavier than it looks. The C of G is not where you expect it either. The lifting eye on the top gives the game away.

I noticed your post over on the Denford forum earlier.
Without the control box, there will be a lot more wiring needed done, but there's nothing insurmountable if you really want to get the machine running.
From the photos you posted over on the Denford forum, you've got a BT30 spindle (it's got an 8 position tool changer), and stepper motors.
Ultimately to get it running, you'd need 3 stepper drivers (plus suitable power supply), a spindle drive, some form of controller, and lots of relays.

If you do decide not to keep it, I'd be interested. I've got a BT35 spindle version, but would quite like a BT30 version as toolholders are far easier to get, so I could swap the required bits.