Member postings for Steve Withnell

Started drawing my version - thing I can't work out is how to establish the centre for the 0.125inch radius? The valley and 'flat' on the tooth I can work out, but finding the centre is defeating me!

Regards

Steve

Thanks Jason, helpful as ever.

Much appreciated.

Steve

Where can I get hold of meccano chain wheel drawings in .dxf format ?

I have an old radio that using rubber drive belts for part of the tuning mechanism and they perish very quickly, as they get cooked by the valves.

Meccano chain drives would look neat and be a long lasting solution.

TIA

Steve

I started off using acidified copper sulphate solution, mainly because I was learning from books that came out of the Ark's library. Then got converted to a big fat black Sharpie and never needed anything else for marking out.

Just 'block sender' and delete, really not worth messing with. You can track the issuing mail server (sometimes) and eMail a complaint, but I think those 'abuse' mail addresses just point at a delete folder.

Regards

Steve

Thanks for the kind offer, but I am after quantity. I can manage with 1mm pitch, it's just that 0.75 or .5 would make for a better job.

regards

Steve

Looks they have good stuff - but only 1mm pitch in Brass (£1.95 each, so should be good!).

I look to them in future.

Regards

Steve

Struggling to find 6mm metric fine crews in brass. Looking for cheese head 25mm - 50mm long.

None of the usual suspects appears to stock these - anyone know of a specialist supplier somewhere?

Steve

Andy, this is how I added a DRO to the Minor. The DRO is simple type from Arceurotrade. Then I just took a piece of aluminium plate and bored a hole in it to be a slide fit over the spindle assembly. There is a caphead screw out of sight which acts as a locking screw to stop the plate swivelling.

The plate is then useful for hanging clocks off...but you lose the depth stop which I miss very rarely.

I drilled and tapped a hole for a mounting plate in the mill casting to hang the DRO off.

I have a graph somewhere of the the DRO readout plotted against the manual readout off the fine feed, apart from a stiction/backlash problem the graph wanders about all over the place!

Warco Minor? I cut these bevel gears on mine and machined the cams for the Nemett four stroke. So the machine does work. You must put a DRO on the Z or it will drive you nuts!

If it was in bubble wrap inside a 75mm tube and a metre long, it can't have been that bent! If Parcelforce managed to bend it without damaging the tube, then they must have had a touch of the Yuri Geller going on!

Steve

I don't like manual backups of anything, because they get forgotten and the media lost. I have a load of USB sticks. Somewhere.

Cloud storage is often free depending on storage requirements and fully automated and 'always on'.

If you are like me and can't quite make the move to moving the electronic copy of my life onto some remote hard drive, then you can buy a NAS drive and have the 'cloud' copy tucked away in the house. I use 'Allways Sync' so that hard drive always contains upto date copies of work from any of my devices. The weakness in that plan, is that I make manual copies of the remote drive onto a portable hard disk once a quarter and then lock that away, off network.

Manual sticks I only ever use for file transfer - typically from the Laptop that generates gcode to the PC in the workshop that runs mach3, though I am tempted to put the workshop PC onto the network and get rid of those sticks altogether, because the temptation then is to alter the drawings on the stick, which then don't match the 'Final' versions on the laptop.

The irony is that I first got involved connecting cnc machines to ethernet to eliminate paper tapes in 1983/4 so I'm a bit behind at home!

I notice that the Axminster versions of the KX1 and KX3 have Ethernet interfaces, I guess that is yet another version of controller board. Anyone know which one?

Regards

Steve

Thanks Jason, I calculated manually 3032 rpm and 156 mm/minute which is a bit more aggressive, but I can see that I've been a bit optimistic with the "feed inches per revolution" value. If I back it off to where it should be I get your numbers. I'll go and run with that, see how it works out!

Regards

Steve

I've been puzzling over the feed rates when drilling with a CNC. I found this table, but it doesn't link to material type. How do I calculate feed rates when drilling?

A specific would be drilling 3mm holes in EN3 square bar as opposed to drilling 3mm holes in aluminium. How do I go about calculating the feedrate in those different materials.  If I use that data, then I get to 150mm/minute in mild steel - is that about right?

Table:
 

Recommended Feeds of Various Diameter Drills

Diameter of Drill - Inches Feed Inches per Revolution

Under 1/8 001 to .003

1/8 to 1/4 .002 to .006

1/4 to 1/2 .004 to .010

1/2 to 1 inch .007 to .015

Edited By Steve Withnell on 18/07/2020 17:07:42

I still have my Warco minor and won't part with it. If you fit a DRO to the Z-axis and think through the machining process when setting up it's perfectly sound. It's also a very good co-ordinate drilling machine. One benefit is that it runs slow enough to cut gears (I've used mine to cut small bevel gears) and run slitting saws.

Good workhorse!

I agree, tilting the work during setup is a better option.

Thanks Dave.

I've been using Eagle and that's full on too, but just about got that sorted. I'm struggling at the minute to move from 2D (Vectric Cut2D which is dead simple) to 3D packages.

Steve

Hi Martin, what thread sizes did Mamod use for the boiler fittings? (Whistle, valve, drain). Dad has a couple or three engines with the various bits missing.

Steve

F360 is pretty expensive - Although I have an Autodesk Eagle licence, which it claims entitles me to F360 free as well, it wants confirmation I'm a student at an approved college? I'm clearly going down the wrong path of internet links...

How long does it take (devoted hours) to get reasonably proficient at producing simple 3D models in F360? I want to be able to (as an example) machine camshafts on my KX1 using a rotary table as the fourth axis and engrave labels round the circumference of a round bar.

Regards

Steve

When I started out wth the KX1, I downloaded an 'app' onto my phone called speeds and feeds. If I bang in Andrew's numbers for an uncoated 3 flute HSS cutter, 0.4 DOC, then it gives a feedrate of 130mm/min roughing and 65mm/min finishing.

In practice what I do for a first time cutter/material is to load the finishing number, then wind up the feedrate overide keeping an eye on finish. I find that I don't break cutters (I've been using 0.5mm - 3mm in the last round of jobs) with this approach. Once I've 'learned' a good number, I then bake that number into future jobs for that cutter/material combination.

One good trick for breaking a lot of small cutters is to inadvertantly set the tool offset wrong on a cutter change and then keep changing the feedrate to solve the problem. Oops.

Steve