Here is a list of all the postings Swarf Maker has made in our forums. Click on a thread name to jump to the thread.
|Thread: Colchester Student Mk1 Won't Start|
There seems to be some mis-reading of the circuit diagram going on here. The top set of switch contacts (6 off) in the upper part of the diagram all relate to the Santon switch.
Rotating the switch from 'OFF' to 'ON' just turns on the coolant pump and the contactor has no part in this.
Rotating the switch further additionally applies power to the terminals of the 'Motor Starter' (contactor). A contactor is used here to avoid the switch load on the Santon switch and to provide 'no-volt' release in the event of a power failure. It may also incorporate a means of disconnecting power to the motor if too much current is being taken.
I will leave things at that point rather than confuse the points made above.
As stated in the earlier part of my posting, you can still use F360 for free under a 'Personal' license. Everything will be as it was under the old 'startup' license except for some features that most hobby folk would not have used anyway.
There are some of us though who have been caught out as a consequence of not fitting into the current license structure. For example, I have used F360 to build up a comprehensive library of obsolete parts for a particular marque of motorcycle in the '30's era. This is for the record, not for any commercial purpose as even when a few new parts are made to these drawings, they are one-offs for individuals at their own expense. It's more akin to a museum archive activity.
It has been useful to use the collaboration aspects up until now as some of the contributors are spread around the globe. Some of them also have access to professional CAD software whose files I need to translate.
With a library of many hundreds of parts, assemblies and drawings I have to choose either to continue for free with a few limitations or to pay for the commercial license.
As many of us have in effect been Beta testers for this software which is still evolving, I certainly would not want to pay full price for a license. This special offer is perhaps a worthwhile thing for people like me though, where so much effort has already been invested.
And yes, I do have backups in generic file formats and could migrate to my other CAD packages or indeed another. However, F360 does suit my needs very well and it's ability to back-track the timeline and edit within assemblies is very useful.
I have no wish to promote the product but when Ian asked his question I saw that he was possibly confused by what Autodesk were doing. The reduced price offering, if it were to suit him, is not well advertised and I thought that he should be advised of it.
Ian, Are you quite clear about the new license structure for F360?
The previous 'free' license was confusingly called a 'startup' license because it's primary focus was on startup type businesses. Hobbyists were treated able to use the software under the same banner.
The new license structure separates hobby use - now called a 'Personal' license, from licenses issued to true startup business users.
If you are purely a hobby user then when your existing license comes up for renewal you you can renew with a 'Personal' license which continues to be free. You will however lose a few features such as collaborative working and the ability to import certain commercial file formats. Otherwise there is no difference.
There is a lot of confusion being expressed on the Autodesk F360 forums and Blogs, but that is the essence of the change.
Anybody who is currently operating with the free to use license can, until the end of this month, take up a special low price subscription offer of $310 (whatever that is in GBP +VAT) per annum in perpetuity.
It has taken a lot of effort for me to fully understand these changes (shame on Autodesk) but I think I have it cracked and can point you to various links on the Autodesk site for you to check it out. PM me if needed.
|Thread: A cord of Ash|
In my rural idyll we refer to 'cord wood'. By this is meant a piece of timber that would be included in a cord volume and as such would be approximately 4' long. After stacking that would be cut for 4 fire sized logs - or fewer if you had the Lord of the Manor's fire to feed!
|Thread: Fusion 360 Licence Changes|
In addition to the loss of collaboration facilities you also lose access to 'commercial file' translation - although open-standard file translation is still supported.
For those still confused, don't expect that the exchanges on the F360 forum will clear up much! However, it's still worth getting a word in.
If you choose not to change your licence you will still have access to all of the things that are being removed in the new licence until your current 'startup' licence comes up for renewal.
If you decide to go for a paid version, don't use the links that you are taken to by the banner. Instead, follow the link in a 'Blog' entitled 'New Free Fusion 360 Subscription Types' where a special offer, expiring end of October 2019, is posted.
|Thread: mystery tool|
All together now chaps!
It's a re-seating tool for water taps. The brass bodied kind of tap with a rubber washer.
I would be much more worried about microscopic (or larger) metal particles being rubbed from either meshing gear through any mismatch of tooth form, and then travelling around the engine. With aluminium as one of the gears you need to be alert to microscopic particles becoming embedded in its teeth, and those then forming a lap which wears the mating gear.
Deviation from specification is not always a sound idea unless you have a very firm grasp of the underlying design criteria and the likely consequences of changes.
Your leaving the forum would be a significant loss to the helpful and well thought through contributions to solving the problems of others. At least stay online for a while to monitor the evolution of the forum. There are many of us who would not wish the forum to degenerate to the level of the lowest common denominator as seems to happen in so many other aspects of our modern society.
|Thread: Mystery Bamford engine|
Pat, looking at your photos you are going to have to dismantle the armature in order to disconnect the old capacitor (condenser). If that is not done it is likely to be a pointless exercise in mounting a 'Brightspark' capacitor at the points plate. You need to follow the 'complete works' chapter on the Brightspark website in order to repair the magneto that you are working on. Any defects in the old capacitor, other than a complete open circuit, will continue to influence the working of the magneto. Even if the capacitor is currently open circuit, it may well re-establish a connection and hence a fault condition, when in service.
I hope that you followed the advice to provide magnetic 'keepers' for the magneto body before removing the armature.
Pat, as you will have now seen, the capacitor (condenser) is contained within the brass body at the contact breaker end of the armature. The centre screw that I said yesterday should not be insulated, actually screws into the body of the condenser. As a consequence you need to retain some of its physical presence - if not its electrical connections. The Brightspark tutorial is good but you need to be very careful removing the slip ring when dismantling the armature. The HT wire from the armature coil usually becomes corroded where it enters the slip ring so clean it well when putting things back together. The wire is just a push fit into the hole and establishing a good contact is a bit hit and miss.
For the WICO style of rotating magnet magneto Martin Perman is correct in that the capacitor (condenser) is mounted in an easily accessible position. The magneto currently in place on this engine would appear to be a rotating coil magneto and with those it is common practice (but not universal) to embed the capacitor in the armature.
The capacitor is embedded within the armature. Unfortunately it can only be accessed by a complete strip-down of the magneto.
Edited By Swarf Maker on 26/06/2019 01:00:14
The resistance that you measure when the points are open is that of the primary coil on the armature. That is as it should be. If there were an open circuit that would be a fault condition!
The fact that there is resistance present is not a positive test however. Shorted turns on the primary coil of the armature will not show up. Also the capacitor is connected across the points and thus across the coil as well. These capacitors are paper/foil/mica constructions and sometimes (but rarely) fail showing a low resistance. More likely is that dampness and corrosion degrades the connections between foil layers and their capacitance value falls dramatically. This failure mode often occurs when a damp/degraded capacitor is exercised after a long period out of service and is the most likely cause of your symptoms. You started with a strong spark, the energy of which the capacitor couldn't cope, and then the capacitor failed, spoiling the tuned circuit and hence reducing the spark.
All repairable/replaceable but not for zero outlay.
That screw is not meant to be insulated. It forms one of the connections to the inner workings of the armature.
|Thread: Where to begin?|
Yes, F360 files can be stored locally. A recent upgrade also means that you can export them to 11 other CAD file formats for use in other programmes.
You can also import quite a wide range of file formats as well. Both import and export translation require you to be connected to the internet and the computational power is then provided by 'the other end'.
I often use the simple QCAD Pro software to generate dxf files and then import them to F360 to start the creation of a 3D model. I also use TurboCAD 2016 Pro Platinum for some of the things that it does best, like gear and thread generation. Files are then transferred to F360 in either dwg or STEP format.
|Thread: Dual speed motor on Hardinge HLV-H - Fast not working|
Before you get too far into the internal working it would be worth rotating the phase connections to the lathe. Under some conditions the generated phases from the converter will drop in voltage and any contactors will drop out until the voltage comes back up and then the motor current draw causes the voltage to drop once again. A self perpetuating 'fault' condition with associated cacophony!
Move all 3 input phase wires round in the same direction once and try again. If that doesn't work then continue to move the wires round one further step in the same direction. If one of these setups works then all well and good. If none do, then a deeper investigation is required.
|Thread: Rulers - my pet peeve|
Rather like the specification of an
"8X( Vintage Stainless Steel Ruler Rule Scale Machinist Tools 20CM Z9N8)"
on ebay at the moment:- " The measurement allowed error is +/- 1-3cm "
I think I could make most things fit within that sort of tolerance!
|Thread: For discussing the merits of alternative 3D CAD programs.|
As a bye-the-bye on CAD, I use QCAD Pro for straight-forward quick 2D drawings. These sometimes get imported (dxf files) into Fusion 360 as the basis for 3D models.
Fusion360 is now my preferred 3D modeling software. The 2D drawing generation from the 3D model is adequate for most purposes and the whole package has great utility, and I really love the timeline features of F360 that make changes and error correction a breeze.
Because F360 is still evolving there are some features that are lacking. For drafting where F360 has shortfalls I use TurboCAD Pro Platinum. Both 3D modeling and 2D drawing generation are fully featured but a bit more hard work.
Saving TurboCAD files as DWG allows the work to be easily uploaded to F360 so the best of all worlds. Similarly the DXF 2D sketches from QCAD can be imported into both T'CAD and F360.
Put 'Paul the CAD' into your browsers search engine. UK agent for all versions of TurboCAD.
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