Alternative to PC based Cnc controllers

Better to provide battens or similar positive support rather than trying to jam in or use glue. Kingspan and foam type insulation sheets seem to compress a bit over time so will fall out if jam fitted even if its almost too tight to shove in. Glue doesn't seem to last more than a few years, say 5 or so, against a condensation prone steel roof. Dunno if cause is the damp getting under, near impossibility of getting roof fully dry before sticking, difficulty of getting full glue line coverage as both roof and sheet aren't super flat or just movement as the roof expands and contracts due to sunlight heating. If it is expansion and contraction might do better with big blobs of silicon rather than glue as being a bit more flexible.

Gotta bite the bullet and re-do my glued on steel insulation in the shop and the jammed in Kingspan between the rafters immediately underneath my new roof. Both done by builder types, with my assistance, disregarding my opinion that the job wouldn't last. No fun in "I told you so" when it means a ton of work for moi to fix.

That said such insulation really makes huge difference. Maybe halves my shop heating bill compared to relying on the 4" of insulation in the walls. Similar effect on heat losses through the house roof. Post extension new roof area pushing double old roof area yet losses through new one are similar to, probably bit less than, old. No regrets from jamming my pedal extremity down and assisting that both be done.

Clive.

John,

Would it were that simple. it's a 35ft x 15ft open sided shed that I've enclosed with a window wall made from pallet timbers & sheet plastic (cost me 2000 screws from Screwfix). It was originally a kennel for a dog breeder (the previous owner of our house), and was never intended to be anything other than an open building of comparatively short life. I replaced the corrugated cardboard & bitumen roof 8 years ago, and now at least it doesn't rain inside even if the condensation drips.

I am planning to move my cnc stuff into a small brick built granary dating to around 1890 when I have finished dry lining it. That will help the roof condensation situation, I agree. However I must disagree about the problem of dewfall inside an unheated building. If the temp reduces such that you get 100% humidity, dewfall cannot fail to occur. We experienced it in the granary last week (9" brick walls + insulated under the slate roof), foggy outside, it cooled off & we got dewfall in the granary as well as all our sheds & outbuildings. Same happened on my parents' farm in Devon, so it's not unique to Kent. Also, if you soak a machine tool at a low temp (say 0C) in an unheated building, then when the ambient air warms, condensation on the equipment is inevitable until the mass warms up. The only way of ensuring dewfall never occurs is to heat the place - not feasible in most workshops, so computer stuff will always be at risk if designed to be inside a house.

Regards,

Richard.

I suggest you don't turn your computers off.

At least you will have plenty of cereal ports.

:0)

Do these controllers support servo motors? encoder inputs? tool changers? 4th axis?

The 990T & TAC-1003T are both "open loop" controls that have Step/direction outputs only & no axis feedback provision. There is one analogue output & one encoder input for the spindle. They have a built-in PLC & come with a "standard interface" PLC program that handles a turret (presumably some sort of standard locally produced turret interface), two speed spindle gearbox switching & other, normally expected, functions.

I did find a PLC manual for the 990T, which showed (at a quick read) almost identical functionality as the Fanuc PMC K/L/M used in the 0 series controls (with which I am familiar), with the same signal addresses used (X for inputs, Y for outputs, F & G for NC/PLC communication, R for freely assignable flags/markers etc.), the same command set & function blocks etc. So pretty much any type of functionality that could be achieved with a Fanuc PLC would appear (at first glance) to be available with these - even the processing times (Level 1 program @ 8 ms) are the same. The bigger problem seems to be limited I/O - I didn't find if the 990T could be expanded, but the TAC-1003T mentions additional modules are available to give an extra 16 inputs & 16 outputs - not a lot in the greater scheme of things, but some of the standard I/O could be re-nominated from the as-supplied PLC program if not required.

From an axis drive point of view, Chinese brusheless servo drives seem to have the option of step/direction control as well as analogue speed control as standard. I got a Bonmet 3Nm brushless drive & motor for a project at work that had this. The drive also has outputs for drive error (loss of steps) and a 1 rotation pulse signal derived from the motor feedback encoder - the control has inputs for each axis for these signals, so the control gets to know from the drive if it has stalled & to give more accurate referencing. A sort of "part closed loop-ish" operation, but not the same as a "normal" closed loop on an industrial control. You could also use one of these controls with normal open loop stepper drives, though these would not have the "lost steps" warning or give as accurate referencing.

Still look like an interesting proposition, though.

Nigel B

BTW, the £17 USB CNC board from Ebay didn't turn up within the estimated delivery time (still hasn't) & was refunded. I have yet to get around to ordering another to have a play.

Jat.

Some feedback for you.

I have little or no trouble with PC's in the workshop environment. Occasionally a keyboard gets some dust or swarf, but are dirt cheap to replace. I prefer a large monitor to the small screens used in the stand alone controllers usually mentioned here. I am very happy with the concept you have come up with. The one thing I would put on the wish list is a touch screen monitor in addition to a conventional keyboard. Keep up the good work.

Bill

I've just indulged in some shameless chequebook engineering. This is a 4-axis controller of a similar type to the lathe controller JS mentioned earlier in this thread. Obviously it's set up for 4-axis CNC milling rather than 2-axis CNC lathe control. This is a kind of self indulgence to make up for spending the last 2 weeks in China and should reduce the time and cost of carriage, as I brought an extra suitcase with me. Total cost for this was pretty much bang on £400, which compares favourably with the cost and ball ache of assembling a PC, BOB, monitor, software, keyboard etc.

Overall, doesn't look too bad. I haven't opened it up to look inside but it claims to have an FPGA for the fast stuff and a 32 bit ARM cored processor and DSP. Also comes with a set of connectors with labelled cable tails. Time will tell how well it works but if not obviously I will blame JS.

I've already started to translate the user manual into something readable. The Chinglish is very strong. If it's a Fanuc clone as I think JS suggested, I may have to download the equivalent Fanuc manual to see if it helps.

Murray

Nowt wrong with that. A definite woohoo, and should keep you out of trouble, and in the workshop, for a while.

Andrew

Murray,

Please let us all know how it works out. That is one of the ones I have on my E-Bay watch list as an option for my new lathe. However, it doesn't seem to have an encoder input, which probably makes it unsuitable.

Regards,

Richard.

Are you sure about that, Richard? This is from the manual I've been cleaning up and digesting recently. There are also quite a few "electronic gear" functions for driving one axis from another, including the spindle.

Do you have the manual? I can send you a copy if you PM me.

Murray

Murray, you are correct because Steve Blackmore has had his threading straight out the box, even done some triple start threads.

Richard, did you miss the bit where it's costs around £400 ?

Wouldn't want you to be financially embarrassed.

John - are these based on the Fanuc controllers? In particular, is the Fanuc post processor the closest to use? I appreciate that you and Steve have the lathe version but presumably requires a similar post.

Also, has Steve posted his experiences anywhere like Madmodder? I'd love to hear how he got on.

Murray

Closest we have come across is the Fanuc 21

The post is pretty generic for lathe except threading on G76 which uses the later Fanuc 2 line build up as opposed to the earlier one line G76

AFAIK Steve hasn't posted about this on forums but will give out any information if needed but he only has the lathe version.

I have loaded code written for Mach 3 that works straight off but there are no threading routines in it. However that same code won't run in Mach 4 which is also supposed to be Fanuc compatible but I know out of the three which two I'd trust.

It's 8 months pocket money, four of which have already been put aside. Could have one this year provided I lay off the beer & cream eggs. Would honestly prefer to pay out for one of these than have to have a PC attached.

Regards,

Richard.

Murray do you have a link to your supplier, Ive been thinking of getting one of these for a while I just never got round to it, however a mate also wants one so I am in the market for two.

Cheers

Shaun

Although I've spent a lot of time out in the Far East, I'm a long way from being any kind of expert in CNC. Obviously I hope that will change in the coming years but in the meantime, there are many more experienced members on this forum. You might call me a CNC pornographer - seen the photos, read the stories and reckon I could put on a good show.

Having said that, I'm very happy to share what I have learnt to date. I know very little of the supplier I bought my controller from other than their geographical location and website. I believe JS knows a lot more about their setup and the general parentage of this controller. From what he says, I may be reasonably safe but time will tell.

I got mine from here. It was delivered to our factory near Shanghai within a few days of ordering and appears to be as described.

Looking forward to getting back home tomorrow. Due to some inexplicable (but hopefully repeatable) alignment of the planets I appear to be on course for 1st Class return journey with Emirates (A380) tomorrow. I am hoping to find a way of making this a habit....

Merry

I'm looking to upgrade my kit, I already have a pretty good 4 axis CNC mill setup at home I just want to get away from the PC keyboard etc.

I'm starting to get to grips with it now, here's somat I made earlier with it.............

For interest I've put a few more images of this in one of my albums

Shaun

Edited By Involute Curve on 15/03/2017 18:27:44

.

I hardly dare look, Shaun ... that is magnificent !!

MichaelG.

Shaun, that looks spectacular.

And seriously uncomfortable for long journeys!

Regards,

Richard

Crikey Shaun, that's really, really sweet!

Shaun

That looks A1!

Would you be willing to send me a few hi-res versions? I'd love to print an update on your article written when it was half-done! I reckon most readers wouldn't begrudge a page or two plus a few words about the machining setup!

Neil