Here is a list of all the postings richardandtracy has made in our forums. Click on a thread name to jump to the thread.
|Thread: Second Lathe ?|
But I want to do a cnc conversion on number 2, and it'll be easier to have my original available to make parts on. They are also nearly identical (Warco WMT300 & Clarke 430) so I can share tooling between them.
|Thread: Gear cutting with a shaper?|
It is the pitch circle disc 'C' that is the critical item, not the diameter of wheel D in that design. I had managed to slightly misinterpret the sketch on the first page & was thinking that index latch 'L' was attached to the fixed body of the shaper. It would require fewer parts, less machining and... index wheels 'D' cut to the correct diameter but not risk the possibility of a wire being compressed and not rotating the wheel during any backlash movement of the shaper traverse.
I can now understand why you were so concerned and apologise for any confusion caused.
It is, however, a mighty clever way of machining gears.
As promised yesterday, I have modelled the effects of changing the diameter of the index wheel.
This was modelled with a 65mm diameter blank, aimed for 60mm PCD, 50mm diameter root, 1mm wide tool at the root, tool depth 12mm, 29 degree pressure angle, using 1mm traverse steps for the shaper. Three conditions were considered. On the left, the index wheel diameter was 90mm, in the middle, 60mm and on the right, 30mm. No effort was made to make a real gear wheel proportions as the illustration was made oversize to exaggerate the effects.
As correctly pointed out in previous posts, the index wheel diameter needs to be the same as the PCD.
Hope this helps
Edited By richardandtracy on 14/02/2017 09:09:45
Sorry - run out of time this evening. Been doing it on SolidWorks and got to leave it behind now. Will get a chance to look at it again tomorrow morning. Will try to get something up by lunch, but by the look of it with 4 off steps at 5mm increments on a 60mm wheel with 29 degree cutter angle and assuming 60 dia & 30 dia index wheel, it produces two very different cut shapes. Need to increase the number of steps considerably before can really show the wheel properly.
Don't think so.
Take it to an absurd limit to consider the effect. Assume index wheel half the diameter of the actual wheel. Move the shaper table 1mm over, causing a 1 degree angle change of the index wheel. The gear wheel perimeter rotates by 1 degree because it's linked to the index wheel, but because it's twice the diameter of the index wheel, its perimeter actually moves 2mm (remember, though, the table has only moved the axis of rotation 1mm to one side while the tip of the gear tooth has moved 2mm), meaning much more is cut off the tooth than you would have expected if they were the same diameter - thus forming a much reduced tooth size.
If they are the same size, both the axis of rotation & tooth tip will have moved 1mm. It's not possible for the shape to be the same in both cases.
I'll see if I can draw it up.
Edited By richardandtracy on 13/02/2017 16:04:50
I must admit I am impressed with the simplicity of the idea used in that link.
However, I think it needs one thing pointed out. The diameter of the indexing slot wheel should be the same as the outer diameter of the gear wheel, so that the rack effect of the lateral translation is replicated at the gear wheel to get a perfect form. If there is a diameter error, it would be better to be as shown, with the diameter of the indexing slot being smaller than the wheel. The effect of the indexing wheel diameter error is to alter the effective pressure angle with the smaller index wheel increasing the effective pressure angle & vice versa.
|Thread: Knurling ( Fusion 360 )|
SolidWorks is the system I use. The effort involved in modelling threads & knurls, along with the memory, processor & file size overheads is really not worth it. Just put on a cosmetic texture for the 3D view. On a drawing, such items are not shown, and most of these systems are aimed at making drawings. As Nick says, knurls & threads are not usually machined direct.
|Thread: Crosslide acme thread|
Metric. I see metric.
Can't get me head round this imperial stuff. I have spent my entire working life in engineering (30 years so far). Only time I ever got to do imperial was playing with aeroplanes for 5 years. I shall shut up further on this, as my views on people persisting with imperial will cause this thread to degenerate.
Possibly looking as expensive as £20 for 400mm with a flange nut from China. If you search, can probably get a ballscrew & nut for no more than £30. I'm a tight-wad, but it seems not worth machining yourself at these prices.
|Thread: Water Cooled Spindle Motor|
Mine is just 30 months old, hasn't been used a lot, or as much as I wanted, but the water cooled spindle hasn't felt even warm. I have a 10l water tank from an emulsion paint pot and a small but very noisy pump that came with the thing, and have used car radiator anti-freeze in it. My usage has been machining pen boxes, lithophanes in acrylic, pen threads and small bits in brass & aluminium. It has not seen a great deal of use, the longest being a 2.5hr spell machining a Lithophane with a 200k line program over an area 9" x 12" with 2.75mm plunge. The stepper motors got fairly warm but the spindle was the same at the end as the beginning.
I think when you get one of these, having to get a VFD is what makes it pricy. The spindles are what, £90-100 on their own or £180 inc vfd: **LINK**
A VFD will have to bought anyway, and from Arc etc the price is a fair bit higher.
Can't advise beyond saying in about 30hrs on my machine, I've had no problems.
|Thread: 1.5mm milling cutters|
How about 10 for £6.50?
**LINK** Depends on material. These work OK on plastic & non ferrous. Must run fast though.
|Thread: Water Cooled Spindle Motor|
The question has to be: What do you want to do with it & what power?
I have a watercooled 3 phase 800W spindle with VFD. It's good for engraving & routing & light milling cuts in aluminium & brass. It was the one that came with my Chinese 6040 router/engraver. I plan on adding a 300W DC spindle to my cnc lathe as an engraving tool when using it as an X,Z,A machine.
The VFD I have interfered with my cnc PC - a plastic cased Dell with metal spray RFI shielding inside. I tried shielded cable & putting the VFD behind steel blocks, but still got occasional glitches. When that Dell PC died, I used a metal case PC and all the RFI problems magically disappeared, so be aware of this possibility.
As for runout etc, very difficult to disentangle spindle movement & machine deflection. The bearing life of the Chinese ones is supposed to be 600hrs @ 20000 rpm, better than most hand-held routers, but not sure how that would relate to your machine time.
I have used mine with 0.5mm dia cutters and also 16mm dia cutters. Never had a worry with that part of the CNC. Mostly used to cut wood, brass, acrylic & casting wax.
|Thread: Converting German metal grades to UK|
My local stockist does this pdf chart:
The new BS EN 10277 numbers are basically the German DIN numbers.
|Thread: cutting left hand thread|
The photos are in my album. The yellow box gear train is the Clarke 430, the one with a green box is the Warco. To clarify things a little, I have outlined the gear spider (where hidden by the gears) in white. I hope this shows what you need to be able to cut LH threads.
I was wrong in my first post that the second slot is perpendicular to the first, it isn't, instead it's at about 45 degrees. It is a right old fiddle to get all the gears to mesh with a LH drive idler in there, you need about 6 hands, and there's barely room for 2.
I'll add 2 bad ones tomorrow morning. To get better photos, I'll have to take the drive gears off to see the plates, and given there's no power to the shed where the Clarke is at the moment, and I can only get there after dark.. I will try to get it sorted tomorrow evening, but it's not going to be perfect!
|Thread: What Did You Do Today (2017)|
My horse fell over & got grumpy with me after I connected front left to rear right...
Edited By richardandtracy on 07/02/2017 21:40:21
|Thread: cutting left hand thread|
I have a CL430 and a Warco WMT300, so can compare these 'identical' machines.
On neither of them is there a tumbler to reverse the chuck relative to the power feed. On neither of them is there a screw on chuck. So one helpful thing and one worry disposed of from people who know lathes, but unfortunately not these specific ones.
In the belt box, where you put the gears - see fig 14 in the Clarke Manual on page 15, where it says 'gear train', you will find on the Clarke a slotted piece of metal with a straight slot and the curved slot visible in fig 14. The straight slot is where a single shaft for two reduction spur gears can be attached. This is, unfortunately a problem, as you need to put an idler gear between the first or last gear and the reduction pair, which needs a second slot perpendicular to the main straight one. Sorry, not describing it well. The Warco I have has the facility to put in an idler. If you want me to, I can get a photo of each to show the shape difference so you could make a plate that enables an idler to be used.
If I didn't make it clear, at the moment the Clarke cannot cut LH threads. But it can be made to.
Edited By richardandtracy on 07/02/2017 14:17:12
Edited By richardandtracy on 07/02/2017 14:24:03
|Thread: Hello, I have no idea what I am doing|
When I saw the title of the thread, I thought 'I resemble that statement'. Not just with model engineering, either, more as a whole life experience.
|Thread: tool misuse/abuse|
And plumbers, I'm sure they have all sorts of sizes to make sure you HAVE to use the wrong tool.
|Thread: Beginners lathe|
What can I say? When I was in your position, I got a Warco not a Peatol/Taig... I have done a great deal or work on my Warco, and at no point have I felt that the lathe has let me down. It's always me that's the weak link in the chain.
If you are going to have a workshop of any sort, I think there is no need to put much emphasis on portability. Only rate this need highly if you are going to have to use an office/dining room/kitchen and pack everything away afterwards.
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