Member postings for Bowber

Well done, it's great watching the machine make such a nice thread isn't it.

The first time I used it was to correct a mistake when I accidentally used an M6 twin start tap I didn't even know I had so I had to create a brass bolt to fit.
I've been looking at jigging up a motorcycle cylinder head to thread mill the exhaust nut thread out to a larger size and make a new flange nut to suit but it didn't need to be done in the end.

Steve

A few years ago I got 2 single point thread mills from America via Ebay for sensible money, I've not looked to see if they are still available though.

They work very well and I use the threading wizard in Mach3, my first one was a twin start M6 brass bolt and it fit perfectly, the great thing about thread milling is you can mess with the mess with the sizing to get a nice fit if it only mating with the one thread.

Steve

Hi all.

I've just moved my Denford Easimill into my new workshop this weekend and to fit it through the door I've had to remove the table and saddle from the knee. So obviously I've given it all a good clean before reassembly but I'm wondering what the spec was for clearance on the gibbs?

​I've adjusted them up to the pint of feeling tight when slid by hand and then backed them off slightly but I've still got about 2 thou of play when I put a DTI on the front of the table about 4" from the centre, most of this is in the saddle (Y axis) I can go slightly tighter but I may get slight binding at the back, the middle and front section has probably been the most used area of the slides so I'd expect this.

The table seems fine and I tend to move my vice and clamping position around to spread the wear but there isn't much room front to back to do this.

I realise there is always a trade off with old machines but it'd be nice to get it within spec if possible, having said that it's now tighter than it was before disassembly.
Also the machine hasn't had a huge amount of use so there should only be a small amount of wear.

Steve

Windows 8 also allows a local account, I've had most windows OS since 98, missed out ME and Vista, and never had a microsoft account yet.

Windows 10 is ok, it's just a bit different to previous versions but the OS is fine. Yes you need to go into the security settings and turn off most of the junk and there is also a keylogger and voice recorder running that is meant to make your use of the Microsoft services more personal (we would call it spying) Just take a bit of time to get used to it and you'll soon be up to speed.

I have my Win 10 laptop running my CNC router via a CNCdrive UC100 usb controller and it runs very well, the old windows XP box before it was very tired.

Steve

A little more general info, apologies if I cover something you already know

For most CNC jobs you may find 2.5D is the best fit, this is just the tool moving on one layer at a time and a lot of CNC machining is just that with 2D CAD drawings of the profiles being used.

Items like the fan blade would need to be drawn in 3D CAD but I'm not sure continuous 4th axis machining would be essential and stepped 4th axis may work fine, however you may get smoother machining from continuous 4th axis.

You can hand code for some 2.5D jobs but importing a 2D CAD drawing of the profiles into a CAM program is usually faster, programs like Fusion 360 has both CAD and CAM in the same program (you also mainly work in 3D) so no import is needed and they also have the advantage of updating the CAM if you alter the part

3D CNC gets more complicated and you generally always need a CAM program to create the toolpath. Most CAM in the hobby range will output these toolpaths as very small linear moves so a large file could have millions of lines of code. Some of the commercial CAM are now taking an allowable error and using that to create a lot of small curves.

Some CAM programs to look into:

Sheetcam - 2.5D CAM, aimed at Hobby use mainly
CAMBAM - 2.5D CAM but some drawing capability, again mainly hobby use but it's a while since I looked at it.
Vectric do a range of programs that are very good and usually are CAD/CAM in the same program.
Meshcam - 3D CAM, indexed 4th axis and mainly linear moves but I think the developer is moving towards including curves.
Fusion 360 - 2.5D & 3D CAD/CAM, very modern comprehensive program but a bit of a learning curve.

These are programs I've used and there are a lot of other programs to try but out of these I've mainly use sheetcam with some use of Meshcam for a few indexed 3D items, I now use Vectric Vcarve for most of my 2.5D cutting and I'm getting used to Fusion 360 and have used its output on my son's 3D printer.

I'm only a hobby user so my experience is limited to machining my own hobby parts so I'm open to correction but I hope I've provided a bit more information on the process.

Steve

I've had a 280V for a few years and once it was set up I can make some nice parts on it, far better than on my old worn Harrison and it runs at the right speed for tipped tooling. The Harrison felt like it was going to take off if I ran it over 800rpm!

Steve

Mines making that squeal they make when the bearings are worn.

The inverter is held in with a couple of screws and with the mess of wires I think I might leave it a bit longer, it's cold in the shed now so:
A, I don't want to spend ages in there and
B, it's warm in the house!

Steve

The cooling fan in my 280 control panel has started making a noise now, it's a computer type fan that blows/sucks air through the inverter.

As some one else noted it's a right rats nest inside the control box and the fan looks like it needs the inverter to be removed so you can get at the screws holding it in.

Steve

It's the fan on the back of the drive motor.

The cooling fan has it's own motor to keep the drive motor cool while running slowly, mine does it sometimes after a heavy cut causes vibration. Probably caused by cheap bearings with too much clearance.

Steve

I haven't been on here for a while due to work and lack of time but the first thing I see when I come on here is the age old argument about is this or that cheating. Seems to me that the OP is having a good laugh at the moment.

My opinion for what it's worth is that CNC is not cheating.

Let me explain with an example.

My dad has no formal training in engineering at all, he just bought a lathe years ago to help make motorcycle bits, he's a bit of a perfectionist and does take advise where he can get it so over the years (and a few machine upgrades) he's made 100's of parts for motorcycles and bicycles.
He cares little about feeds and speeds and just uses his lathe and mill with the experience gained over the years and can make very nice parts. Ask him what surface speed he used or feed and he'll look at you like you're daft though. I've seen him 4 flute carbide cutters on Aluminium and make it work.
He does have some idea what he's doing but the long and short is that he's used to his lathe and tools and how they work.

If I was to present him with a CNC lathe and mill he's be stuffed and there would be broken cutters and crashed tools flying along with the language, so he would have to start learning about speeds and feeds and correct tool usage, chip clearance etc, so in other words he would have to relearn a skill he thinks he already has plus how to draw the parts on a computer and then calculate the speeds and feeds, pick the correct cutter, and account for swarf clearance and waste material dropout issues in closed pockets. Once you've clicked the go button you have to have everything right.

So after completing the machining of a part with the INTENDED results he would have gained new skills and learned a lot more about the theory behind machining materials, that is NOT cheating.

Steve

Sorry, bit slow in answering.

PC is Windows 7 pro 64bit, laptop is windows 10 64bit

My mill is setup with homing switches in series, zero plate, Estop and the normal stepper pinouts. I don't use limit switches but no reason they wouldn't work.
I also have a USB Xbox controller setup.

Mill works smoothly and doesn't seem to have any problems and the Estop and homing switches work fine.

Originally I left the motor tuning as was but I've since retuned it.
I've now got another UC100 for my router as the PC that was running it was 16 years old and windows 2000, nothing wrong while it was running but it's started having boot problems which indicate the hard drive is failing so I intend using the laptop as the main control for that.

Steve

All very confusing but I didn't bother, I just used a new 64 bit computer and a UC100 usb controller.

http://cncdrive.com/UC100.html

There is a UK reseller https://www.cnc4you.co.uk/Motion-Control/UC100-USB-Motion-Controller

Seems expensive but in the long run much better and you can use any pc you want after that, I have my laptop setup with Mach 3 as well as the dedicated pc (laptop is a backup)
Easy to setup and you don't have to alter any settings as the UC100 connects direct to your breakout board and has the same pin out as the parallel cable.

Steve

We used to make our own blades at work and the main failure was incorrect annealing of the weld, after that it was badly ground welds jamming.

Steve

Power feeds are something that while not needed is very useful and gives a much better finish, the same with DRO's, they are not needed but once you have them and learn how to use them you miss them on a machine that doesn't have them.
Want to work in metric, easy just switch it over, then back to imperial when you want.

Steve

The current inverter versions of these lathes use a separate cooling fan that comes on with the power to the lathe.

My 280V uses a 1.5kw motor and only uses 1 belt, I'm not sure how long the belt will last as it's only a small section but it seems to handle large diameter work without slip so far.

Steve

Hi

The normal way is to remove the govoner and use the throttle like a normal engine would so you have to rig a direct cable or rod connection to the throttle butterfly. You can usually leave most of the parts connected and add a couple of closing springs.

You'll need a parallel shaft but you can use the taper shafts at a push, and look on ebay for centrifugal clutches, there are a few, then belt or chain drive to the wheels.
Or as Mark said make a slipper clutch which actually works far better than you'd think.

Just to add a bit of background, I race lawnmowers and we do a genuine 45+ off road with no suspension so we're doing this sort of thing all the time.
The main thing is to make a safe kart to fit the motor to and it's a good idea to add a lanyard cutout.

Steve

I think it's more the amount of packaging and yet the bottle is on an outside edge with no benefit from the packaging

£D has a lot of uses and you generally get less mistakes in your drawings created from a 3D object.

In industry it's also good to add the ISO view into the drawings so the manufacturer has a good idea of how the part is meant to look.

However for hobby use it's not as relevant unless your using 3 axis CNC with raster machining (each cut is a slice from the model) and 2D is usually more than adequate.
Even with CNC I find myself doing most of the code by hand or with the wizards in Mach3
It can help some people visualize how they would make a part but I usually have the machining sequence sorted in my head the second I look at the part.

Steve

We used to add coloured tape to the bars, however there was always some numpty who would cut off the end with the colour code!
And if you came back into the shop grasping the end with the colour code on you didn't do it again!

Steve