Topics

1

Show"N"Tell ( What you have made with your CNC machine.) / cutting MDF and Plywood

« on: December 06, 2015, 05:06:03 PM »

Heelo guys,

Simple question. I am basically profile cutting 6mm and 3mm plywood and 3mm MDF with Scrappy my home made CNC, I am cutting with 2mm 4 flute tungsten carbide end mills at 500mm/min, 1mm depth per cut @20,000rpm on KRESS. The problem is I am getting through them at a rate of knots, they are getting hot and snapping off, is there a good quality bit that will last longer than 10 minutes.

Stewart

2

Show"N"Tell ( Your Machines) / Scrappy does his first cut!!!!!!!

« on: September 24, 2015, 06:07:02 AM »

After nearly 2 years (maybe more) Scrappy (sorry Tweakie......... ) has cut for the first time. OK it was only a 50mm square out of 4mm plywood, but we did it and it cut it nicely, square and true, not bad for a complete novice.
As his name suggests, Scrappy is made out of scrap bits off old machines from work, with a few parts made by a local machine shop. He has a Kress FME 1050 machine head and the drivers are off an old labelling machine, modified to run off a PC via a breakout board (a UC100 motion controller is in the post) to improve the steppers performance, cutting footprint is not huge but it should suffice X = 360, Y = 390 and Z = 120.
I now have to work on a simple but effective method of clamping/securing sheets of plywood to the bed after I have given the bed a skim when my larger end mills arrive. I couldn't take a video of the first cut as my hands were busy hovering over the E-stop and main isolator just in case!!!!!!
I have noticed though that on start up the Y axis ticks and moves a step, this is caused by the breakout boards on board relay clicking in and out for a few minutes??? (cheapo Chinese unit, my fault I know), after a few minutes that stops and the Y axis is silent, also when jogging the X axis I can hear it ticking during its movement, this seems to only happen when its jogging and no other time. Teething problems associated with cheap and untested units, hopefully I shall be investing in some proper microstepper drives from CNC4YOU in the not to distant future as I can only full step at the moment and Scrappy becomes very, very noisy when the Y axis is slowing down to negotiate a curve.
Apart from these minor faults we are up and running, I shall try to get some video of Scrappy in full motion soon, thanks for your help in getting me this far.

Stewart

3

Building or Buying a Wood routing table.. Beginnners guide.. / Future upgrade of first build

« on: August 04, 2015, 05:16:25 PM »

Hi all,

I have built a router/milling machine basically out of scrap parts, with a few bits made via a friend. Now I have had it running dry as I have no cutting head at the moment and am waiting to buy a Kress 1050 head, once in my hands I can get cutting. It is going to be used mainly to cut plywood and MDF with the odd bit of Aluminium work, nothing big though. Now in the video you can see it moves fairly slowly compared to many others, this is down to using M16 X 2 pitch screwed rod for the leadscrew, the stepper for the Y axis is a VEXTA PH299-4.6 and the steppers for X and Z are VEXTA PH268-1.6, again these use M16 x 2 pitch screwed rod for the leadscrew, the drivers for the motors are what was used when they belonged to the labelling machine originally so data for them is non existant but they work, this is conected via a cheapo BOB to my PC running XP.
Now during testing and setting up I can get it running faster than the video shows but it stalls if I push it past 1300 in MACH3 motor tuning, on investigation the data for the motors show the torque at less than 1Nm (0.883 to be precise) not sure about the 299 motor though as I can find no data for it, but am presuming this too will be on the low side on the torque front. So this got me looking into improvements and a load more questions than answers. The upshot is would it be better to use 16mm x 5 pitch ballscrews for all axis's? Change all the motors to a NEMA23 Hi torque motors (4Nm)? And have 2 motors run the Y axis instead of 1 running 2 belts as I have at the moment. This will obviously require new drivers and a new power supply, with the amount of different manafacturers and suppliers I am getting baffled by the complexcity of choices, can someone please point me in the right direction, cost is the limiting factor as I can't afford the likes of GEKKO drives but don't want to buy stuff that's not going to last 10 minutes......................ideal world, cheap but reliable and UK if possible.

Video of my machine...................https://www.youtube.com/watch?v=nG2lSQl4IQ0

Many thanks in advance

Stewart

4

General Mach Discussion / windows 7 confusion clarification please

« on: July 18, 2015, 10:17:26 PM »

Hi all, I have a home made CNC running on an old XP machine and it runs ok.

I have been given an oldish Dell Optiplex 780 and would like it to run my CNC, I formatted all the old stuff it and installed Windows7 32bit OS, installed Mach3, plugged it all in and....................nothing? Double checked all pin configurations etc and they matched what I had on the old XP machine. Put the old XP PC back on and away it went. Now reading through all the relevant threads here it only states that Mach3 will NOT run on a 64bit OS, now after digging around on the Dell website I have found the documention for the Dell unit and the processor is a 64bit unit. My question is, is it the OS or the processor that needs to be 32bit???
The main reason for changing the PC from XP to 7 is so I can easily network to my office PC were all my AutoCad and CamBam files are and my sons PC (Windows8.1).

Sorry for asking another question on a long and painful subject.

Thanks in advance for your help and support.

Stewart