What 'decent' Milling machine?

[JohnHaine]

I have a little Denford and it's excellent for what I want to do. A Triac would be nice as it's bigger, about the size of my VMB, but I don't have room for it. Unless you are very particular I'd have thought a Triac would be a good buy. When I got my Novamill I was thinking of converting an X1 or buying a KX1, but the Denford knocks those small machines into a cocked hat, it's just in a different league. A Bridgeport is great, but takes up lots of room, and is very very heavy! I would guess that with a Triac you would get the same accuracy as a Bridgy but won't be able to shave off metal as the same rate.

As for what it's worth, things are worth what people will pay. This particular one is not in an auction but you could try making an offer. I think eBay gives you a facility to see previous deals on similar items, so you could see what's been paid in the past? The price looks a bit high to me but I've seen some high prices for Denfords on eBay.

[Chaz]

I have a little Denford and it's excellent for what I want to do. A Triac would be nice as it's bigger, about the size of my VMB, but I don't have room for it. Unless you are very particular I'd have thought a Triac would be a good buy. When I got my Novamill I was thinking of converting an X1 or buying a KX1, but the Denford knocks those small machines into a cocked hat, it's just in a different league. A Bridgeport is great, but takes up lots of room, and is very very heavy! I would guess that with a Triac you would get the same accuracy as a Bridgy but won't be able to shave off metal as the same rate.

As for what it's worth, things are worth what people will pay. This particular one is not in an auction but you could try making an offer. I think eBay gives you a facility to see previous deals on similar items, so you could see what's been paid in the past? The price looks a bit high to me but I've seen some high prices for Denfords on eBay.

So I found a Denford Traic PC, dont know much about the control system. What will the cost be to convert to Mach3? How much of the electronics is reusable?

[Jess]

So I found a Denford Traic PC, dont know much about the control system. What will the cost be to convert to Mach3? How much of the electronics is reusable?

I think quite a bit technically is. Denford have been pretty good at providing documentation and so forth. So, in principle, you can probably wire a breakout board to those drives, if they're working.

However, the electronics are often pretty old and basic. Most of the conversions I've seen seem to replace everything, except perhaps the motors and maybe the transformer.

Personally, I'd budget for replacing all of the electronics.

[Chaz]

I think quite a bit technically is. Denford have been pretty good at providing documentation and so forth. So, in principle, you can probably wire a breakout board to those drives, if they're working.

However, the electronics are often pretty old and basic. Most of the conversions I've seen seem to replace everything, except perhaps the motors and maybe the transformer.

Personally, I'd budget for replacing all of the electronics.

Thanks, including motors?

[Jess]

I think if the motors are working (at a guess, they probably are), then I think they'll be just fine.

I'd emphasise the 'budget for' though; worst case, you might have to fork out, but obviously, every penny you don't fork out, is a penny you can spend on your vices (and clamps, endmills etc.,)

The problem with the stock electronics is that it's basic (eg., the drivers are probably only half-stepping etc.,) and conservative (voltages are lower than necessary etc.,). So, it's not going to run as smoothly or as quickly as it otherwise could.

Having said that, it's also quality stuff; so it's often worth flogging the bits you don't need on eBay, especially if they're working - last I looked the motion control and driver boards seemed to fetch a decent price.

On my very small Denford, I've only replaced the stepper drives and DC supply (the original was part of the original drive board). I've been able to keep the door latches, e-stop, various relays, spindle control board, transformer etc., The main reason I replaced the drive board was actually that it was a real pain to interface to. After a couple of months of 'is it the drive or is it the BOB or is it my wiring' hassle, I broke down, bought a Gecko and had the machine working (with LinuxCNC) in a couple of days.

[Chaz]

I think if the motors are working (at a guess, they probably are), then I think they'll be just fine.

I'd emphasise the 'budget for' though; worst case, you might have to fork out, but obviously, every penny you don't fork out, is a penny you can spend on your vices (and clamps, endmills etc.,)

The problem with the stock electronics is that it's basic (eg., the drivers are probably only half-stepping etc.,) and conservative (voltages are lower than necessary etc.,). So, it's not going to run as smoothly or as quickly as it otherwise could.

Having said that, it's also quality stuff; so it's often worth flogging the bits you don't need on eBay, especially if they're working - last I looked the motion control and driver boards seemed to fetch a decent price.

On my very small Denford, I've only replaced the stepper drives and DC supply (the original was part of the original drive board). I've been able to keep the door latches, e-stop, various relays, spindle control board, transformer etc., The main reason I replaced the drive board was actually that it was a real pain to interface to. After a couple of months of 'is it the drive or is it the BOB or is it my wiring' hassle, I broke down, bought a Gecko and had the machine working (with LinuxCNC) in a couple of days.

Thanks. Sounds reasonable. Does anyone have quick numbers for the cost to do this? Considering there is a converted (Mach3) Triac on Ebay for £3250, how much cheaper should I get this to make it worth while?

[Jess]

Someone might have better numbers if they look for the actual specifications/cheaper suppliers/use a slightly larger envelope for calculations, but I'd guess you can probably easily spend £500-£800 converting one depending on the parts you use even if you're 'just' replacing the stepper drives and you've got a few of the things you'll need.

These aren't recommendations as I've not personally used these - I'm just using the prices as a guide:

Geckodrive G213V drives (80V, 7A digital step drives) are $166 each, and an Ethernet Smoothstepper is $180. So, three drives and motion control board run to $678; once you get it shipped and Customs and Excise take their chunk of flesh for Duty and VAT, you might as well assume that that figure is already in GBP. Alternatively, you can get 80V, 5.6A drivers from Zapp Automation (a UK supplier) for £84 each, which with the smoothstepper and shipping sounds like it comes out to about £450.

On top of that, you might need breakout boards and you'll definitely need various cables, wires, mounting brackets, a mounting plate for all the gear and many, many cups of tea. So, yes, it's very easy to spend more than you meant to getting it working, so it's definitely worth doing some proper working out.

It gets rather difficult comparing the value of Triac models; one might have an automatic tool changer, another might be fully enclosed, another might be 13 years newer etc., If we're comparing against the one on eBay with the lurid guards, then that seems to have a coolant system installed. These are all potentially useful, but their value to you will vary depending on what you're doing (and some are easier to retrofit than others!)

What power supply does a Triac mill require BTW? If it's more than you can get from a standard 13A mains plug, you could get a nasty shock in the form of a bill for installing one of those circular sockets (unless you're lucky enough to already have the right one).

[Chaz]

Wondering if this is the same mill?

http://www.mycncuk.com/threads/1605-Denford-Triac-Mill

Seems a lot might be reusable. So budget for a cheap retrofit? Budget for going servo versus stepper? Info welcome, many thanks.

[JAZZCNC]

So I found a Denford Traic PC, dont know much about the control system. What will the cost be to convert to Mach3? How much of the electronics is reusable?

Depends on how old and what's inside.? Often if converting your better just replacing control and the drives with modern stuff. You'll have a far better performing machine.

The AC Transformer can be re-used but often the Caps and Bridge rectifier are on one of the boards your removing so you'll need to make a little board with new caps etc or use another PSU.
For this reason I prefer to use a new often higher voltage toroidal supply has the steppers are often well under performing. Along with smaller Switch mode PSU for Relays etc to save messing around with differant size Caps etc for differant DC voltages required. The stock transformer gives several AC voltages.

The Spindle speed controller can be re-used but you'll need Controller or BOB that can provide 0-10V signal.

The Contactors and Relays can often be reused, as can most of the other bit's n bobs inside.!

Not difficult to do but Not something I'd encourage anyone who as NO experience to take on.!!

[Chaz]

Depends on how old and what's inside.? Often if converting your better just replacing control and the drives with modern stuff. You'll have a far better performing machine.

The AC Transformer can be re-used but often the Caps and Bridge rectifier are on one of the boards your removing so you'll need to make a little board with new caps etc or use another PSU.
For this reason I prefer to use a new often higher voltage toroidal supply has the steppers are often well under performing. Along with smaller Switch mode PSU for Relays etc to save messing around with differant size Caps etc for differant DC voltages required. The stock transformer gives several AC voltages.

The Spindle speed controller can be re-used but you'll need Controller or BOB that can provide 0-10V signal.

The Contactors and Relays can often be reused, as can most of the other bit's n bobs inside.!

Not difficult to do but Not something I'd encourage anyone who as NO experience to take on.!!

Thanks. Understood. I'm happy to do the electronics, sounds like a perfect match for a lot of new kit.

Trying to find some details of the spindle etc to see if it matches what I need in terms of speed / power.