Here is a list of all the postings Alan Wood 4 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Making a superglue chuck adapter for brass wheel|
Clockmaking and Modelmaking - Tools and Techniques by William Smith pages 14 to 20.
Bill refers to Eastman 910 as being the original source of glue which subsequently had a lapsed patent and morphed into other brand names. I assume he came across this and its application while employed as an engineer at Oak Ridge, TN.
Two replies : -
John thanks for your reply - I also use the masking tape and SuperGlue on my CNC table. I agree the blue or green tape has best adhesion. (There is quite a bit about this on John Saunders NYC CNC). I tried it for cutting wheels on an arbor and in this case the wheel and arbor diameters needed to match or it was possible for the wheel to be pressured by the cutting action and would 'tip' and loose adhesion. It was also difficult to not get a rotational moment on the edge of the wheel blank when truing the outer diameter to size. What helped both these was to tap the centre hole in the arbor and physically screw the wheel blank in place with the masking tape and super glue inhibiting the rotational movement when turning to size and the fliping when cutting. Clearly the tapped hole will be smaller than the wheel centre clearance hole so when finishing the wheel hole to size you need to drill deeper into the arbor to allow a machine reamer to achieve size. This is not a problem but needs to be considered.
Of late I have been cutting wheels on the CNC mill using both a fine end mill into the blank held horizontally and also with a conventional wheel cutter in the mill and the blank held vertically in an automated rotary mount in the A axis. Horizontally I have used the SuperGlue and masking tape method but have still used the conventional arbor technique in the A axis. Experiments continue but the results have been very good.
Mark thanks also for your question - nothing magic about sliding rather than winding. I just like to not dither speed wise with the glue sat there on the arbor and also a solid push into place flattens the glue film and the final winding of the tailstock finishes it off. So all about speed of action more than anything. Do 'have a go' and don't worry if you mess up one or two first attempts. It is all about learning (and playing) and the buzz of success when you achieve it. When you are learning there is no such thing as a dumb question only how dumb you are made to feel by the person answering. Feel free to contact me on direct mail if you wish.
Apologies for the size and the generic nature. The side view of the cutter is also generic but if the arbor is larger than the blank you will get the 'thicker' section of the cutter impacting on the arbor.
Hi NDIY, this is a difficult one to describe ...
The cutters will be PP Thornton or similar and the profile of the cutter 'side on' is the shape of the tooth and then it thickens out for strength. If the arbor is larger than the blank the cutting action back and forth across the wheel will see more resistance as it meets more aluminium that it needs to do.
Likewise if the arbor is less than the diameter than the lowest point of the tooth there is no back resistance as the cutter passes through the brass only and providing the arbor is not dramatically less than the tooth depth will still provide good support for the cutting action.
If the arbor to be identical in diameter to the wheel OD so it gives full support, does not resist the cutter more than necessary and given the two metal sandwich will help reduce cutter burrs.
I still tend to keep it just a bit less than the full wheel diameter so I can see what is going on with the rear face of the blank and know that the cutter is going all the way through.
This probably needs a picture to make sense, I'll knock one up and post in a minute.
Chris at ClipSpring gives reference early on in his John Wilding Large Wheel Clock project to the late William Smith from the USA who perhaps did not originate but certainly popularised the use of a SuperGlue arbors in his series of clock making and tooling books.
Bill's books and videos are still available direct from the US and also from a UK outlet. Chris has expanded its use to fixture plates on the milling table to replace vacuum plates and magnetic equivalents. You will notice that in Chris's videos he still uses Bill's special concoction paste for metal polishing.
Bill suggests that standard single applicant SuperGlue goes off better at an air interface. (At the time of his authorship twin pack SuperGlue might not have been readily available). Bill postulates that having the grooves in the end face of the arbor increases the net length of air interface and therefore makes the bond stronger. Once stuck the finished wheel does take some removing and heat while recommended does have the effect of noxious fumes. I note the comment above that the grooves also perhaps allow 'squash distribution' of excess glue into the grooves to give a more flat/even fixing surface between the brass and the aluminium.
To answer the original question by TickTock and with apologies to the Grannies and their eggs : -
The arbor needs to be ideally the same diameter or ideally a bit less than the wheel OD being cut in order to allow the tooth cutter to pass through the brass and into the softer aluminium backing. The arbor's whole purpose is to provide support to the tooth cutting action.
The blank arbor should be mounted in the lathe chuck. (Once mounted it is not removed until the wheel is completely finished). After mounting the arbor, the grooves are cut into the end face. There is nothing magical about these but a 2-3mm gap (land) between grooves works OK and the depth can be similar. A rounded end cutter is a good profile to use cutting perpendicular to the arbor front surface. A hole is drilled into the centre of the arbor to be larger than the desired size of the finished hole in the wheel being cut.
Having cut both the grooves and the centre hole the arbor should be faced off. This removes any residual burrs that could 'push' the blank away from the surface and ensures that the face of the wheel blank will be axial to the lathe bed.
The arbor is slowly turned in the chuck and single pack SuperGlue is applied (not too excessively) onto the 'lands'. The chuck is stopped. The oversize wheel blank, having been degreased and having an undersized central hole is held in place by hand on the point of a centre in the tailstock and the tailstock is slid (not wound) to impact the blank onto the arbor face. The tailstock is locked in place and the handwheel wound quickly to apply pressure to the wheel blank against the face of the arbor and then the tailstock adjuster is locked in place. After 5 minutes the wheel will be fixed solidly. Some would recommend having the chuck slowly turning while this placement is done.
The blank is now turned to the specified OD for the wheel being cut. Cuts should not be aggressive as they will be applying a shearing force to the bond.
Once the wheel is cut to size the edge of the wheel is marked with a Sharpie pen or similar and then three adjacent teeth are cut back and forth until the marker inking disappears. This defines the depth of cut and the cutter now needs to be locked at this depth. The remaining teeth can now be cut and once all teeth are finished, the final action is to drill and ream the hole in the blank to size. This ensures concentricity of all processes in the wheel manufacture. (There is an immense feeling of relief when the final tooth is cut and it is the same size as the others ... or alternately the neighbour's garden will receive an aluminum/brass addition for its Gnomes to play with).
Assuming success, the only problem now is getting the newly cut wheel off the arbor and heat or a solvent will be needed for this with due respect to any fumes.
The arbor can be stored for future use but will need an initial facing to clean off the prior use glue and grooves before repeating the process.
Hope that helps TickTock (and any others not yet elevated to Granny status).
|Thread: Vogvivo CNC router - Is anyone using one of these?|
I obtained a CNEST3040T from an EBay second user which seems to have some of the components that are being used on the KX1. I have found the 3040 adequate for PCB milling at 5k rpm and have also run PCBs on my Tormach 440 at similar speeds.
You might want to consider adding limit switches to allow auto homing and also to give protection from overrun within the table and Z limits. I made some modifications to Mach3 that I found on the web to accommodate this and also for a Z height setter.
I use FlatCam to convert the CAD files into G Code.
The biggest issues in running the PCBs are the type of cutter you use and how flat you can grip the board to the mill table so as to avoid variations in depth of cut.
I have done some write ups here on my findings and there are various follow up pages. If you want some more info let me know.
|Thread: Angel Eyes.|
All of the ring lights I have used have had a small enclosure containing a switch mode power supply in series with the power lead. Although specified for 12V operation the ring LEDs are powered from 5V derived from this PSU and this makes them very tolerant to the input voltage from around 10V to 18V.
I repackage the SMPU in a small enclosure with a standard plug top connector to allow easy connection to standard PSUs.
It is also important to choose the largest diameter light you can source to reduce 'chuck shadowing'.
See **LINK** for more details on my versions.
|Thread: Polishing Acetal/Delrin and other plastics|
Slightly relevant but Polywatch is a compound for polishing scratches out of watch faces and is particularly good. It appears to fuse the material over the blemishes. Think it is on Amazon.
|Thread: Milling Machines - Myford vs Sieg|
I agree with Clive on all points. I also have a socket and cheap battery electric driver to make big movements on the Z axis.
This is where I apologise on the basis that I am currently in NZ on holiday so I can't easily get to the serial plate to give you the info on the motor ......
The motor was the standard fit by Myford and when I talked with Newton Tesla on the controller needed they knew the item in question. I believe it was the 1/2 HP version and I have never managed to stall it so it has some grunt. Although it has a belt drive from the motor to the spindle I have never changed the belt position, having used the NT speed controller for all activity. Once again I am red faced in not being able to give you the specifics at this time.
I will be back home in a few weeks so I can update you then. One of my close friends is house sitting so I could get him to fill in the details if you are keen. You could also ring Howard at myford-lathes and tell him I sent you (01225 812155 or 07753 610420).
Looking around I can see the one you might be considering and this is in green livery suggesting an earlier model. Tony's site (lathes.co.uk) gives a run down of the differences.
I have no experience of Sieg products having only read comments on the forum and elsewhere so I cannot objectively compare the two options you are considering.
Sorry that is all a bit woolly but hope it might help.
I have a VMB in the blue colour scheme that I bought from Howard at myford-lathes.com. It had a 3 phase motor and I fitted a CL300 single phase to 3 phase speed controller. This works very well.
The VMB is an old but sturdy design with good XYZ limits It has a R8 taper and you can get all manner of tooling to suit. I generally use an ER25 collet sleeve as standard.
I have fitted basic Chinese scales to XY and Z with a simple readout display.
It is lovely reliable machine and if you can get one that is clean and not too expensive it will serve you well. I have to say that it now sits along side a Tormach CNC but they are mutually beneficial and complimentary in what they get asked to do.
There are some more details on my blog www.altrish.co.uk. If you want some more help send me a PM otherwise message via the blog email.
|Thread: Fusion 360 Licence Changes|
See the following support document on renewal as a hobbyist/non-commercial
Even if you have an existing account you still have to follow the 'See if I qualify' path.
|Thread: Bushing for clock arbor|
No offence Michael, you just seem to be respected as being the go to reference source for all things web.
David, you might want to get to know a Preacher.
This is a device with three sharp prongs. Regard it as being a three pronged punch. You place one prong exactly in the location of where the arbor should be sitting and then orient the device to allow the other two to sit somewhere on the clock plate and then give it a sharp tap. This will leave two reference dimples that you can refer back to in order to verify your new arbor hole is in the correct position. The three prongs are usually set to have a uneven spacing so you cannot get the orientation wrong. You can knock one of these up in no time.
If the hole you are working on is really adrift you can use the Preacher to set the two references and then drill the arbor hole out completely oversize and plug it with a piece of brass. You then replace the Preacher in position and tap it gently once again to get a new centre in the plug to re-drill the arbor hole in the correct position. If you put a slight taper on the drill out hole with a reamer/broach then the plug can be tapered to match. The taper needs to be from the inside of the plate so the plug is being 'pushed' deeper into the taper by the arbor (in practice it doesn't move). Use a graver to get the taper on the plug. Overall it is quite satisfying process to do.
You will find that finishing of the plugged hole can be done to completely remove any witness marks that this remedial work has been done. Clearly you don't want to mark the plate surface when removing the excess of the plug that with even the best skills will initially be sitting proud. It helps if you have a piece of 35mm camera negative, punch a similar size hole in it to the plug and then glue it to the plate surface to sit around the plug. This will protect the plate until you get the plug pretty much flush.
I am sure Michael will be able to find you lots of references to Preachers and the process I have outlined.
|Thread: Trip to New Zealand|
Thanks to everyone who has posted and sent PMs all of which are very much appreciated and the sort of info that we were looking for (the royal 'we' there but perhaps slightly dissimilar aims and interests for the trip).
We are booked to visit NZ (North and South) later in the year and would appreciate comments / recommendations from any readers in country. Particularly interested in locations with an engineering bias, model rail etc
Rather than clog the forum please contact via PM.
|Thread: Deburring small items after parting off|
I got the impression that someone of Joe's depth of mechanical and electronic ability was not asking for a tutorial on how it could be done but instead having the vision to share a simple way of deburring small pieces for those needing a quick fix solution. It is elegant in its simplicity.
Thank you Joe, the idea is much appreciated. Please don't be another to follow the TTFN route.
|Thread: Total cost + import for Tormach PCNC 440, and alternatives?|
Importing a Tormach to UK is straightforward using ACC Worldwide in Kent who are the preferred agent used by Tormach. They arrange everything and you can track your delivery all the way to your doorstep.
Tormach products are not CE approved but this is not an issue if you are going to use it for your own non commercial use.
The 440 is a 120V AC product and you will need a transformer which is not a problem with many potential suppliers. I use one from RS product.
Due to the US hike in import duties of products from China the prices have risen on the Tormach products. You can find my spreadsheet with the latest prices list costs of all the Tormach mills and accessories on my blog via this link.
The sheet gives you a full landed costing into UK and you can change the F/X to current market rate. There are quite a few other posts on the blog relating to the Tormach use. Note that as yet there is no 4th axis facility on the 440 but it is road mapped and there are other ways to address this should it be a requirement.
I bought and imported a 440 around 3 years ago and have not had any problems with it. The key aspects that swayed me were their PathPilot software which is excellent to use and the depth of support on my lack of CNC knowledge both direct from Tormach and from the many forums. PathPilot is addressed directly from Fusion 360 which in turn has integrated CAM and does not cost you anything as a private non commercial user.
I would be more than happy to demonstrate the machine to you or others on receipt of a PM request. I am in the Newbury area of UK.
Edited By Alan Wood 4 on 25/06/2019 09:19:34
|Thread: Feeds and Speeds! 0.4mm milling cutters...|
Attached image are two examples of the Think & Tinker bits.
Left hand one is their 15 degree 2 flute tapered stub ZrN coated and right hand one is 60 degree mechanical etching bit.
Both have 5 thou tips.
Sorry about the image but was struggling at this magnification.
I prefer the left hand one as the taper is so slight that it eliminates width of track variations on my vacuum table.
Joe clearly has much more experience than me on the subject. I have seen his set up first hand.
My business life (W&D) also revolved round RF comms where we used a LPKF machine for PCB prototyping on Rogers substrates including brass backed.
Having spent some time evolving my pcb milling process here are a few comments.
I use FlatCam to create the CNC code from Gerber and Excellon files out of GSpark. FlatCam was the first program I tried and it does everything I need without looking further. It allows default start up and shut down GCodes to be embedded in the export code to the mill (in my case a Tormach PCNC440).
I run at 10,000 rpm (maximum possible on the 440) and at 150mm per minute with a 5.1 thou cutter. While I ramp and spiral in when cutting metal I rarely have the real estate on my pcbs to allow this luxury. I dive straight in and cut and it has not been an issue.
I found that tapered engraving bits to be fine providing the pcb material could be clamped flat. If the material is not flat then variations in cut depth result which in turn leads to a wider cut through the copper (think about the geometry). I tried 10 degree cutters to minimise this and found them to be very fragile. If tracking is wide this may not be an issue.
I subsequently found proper fine milling bits from Think & Tinker that which are parallel for the first section and then taper up. They can be supplied with collars so collet mounting is repeatable. They are expensive but are good if you need to go to fine detail.
I tried various clamping methods for the pcb material to try to eliminate the bow. Single sided board is the worst as having the copper on one side causes a 'surface tension' style bowing from the laminating process. In the end I solved this by designing and making a simple vacuum table which runs off the 'hoover', This was an amazing success for a finger in the air idea. The Fusion 360 file is available if anyone who wants to try it.
The vacuum table while solving the clamping does mean it is not prudent to drill holes all the way through the pcb and potentially damage the vacuum table surface and or damage the carbide pcb drills. I therefore drill to almost break through and then go round the board afterwards with my high speed bench drill. With the centres already spotted it is a quick process.
One option that could be used but not tried as yet is to put 'gaffa' tape or similar on the pcb back side to provide a finite spacer and allow some additional depth for through drilling.
Finally I use mist coolant (via a Fog Buster) when milling the boards. This is the same as I use for metal machining (Qualichem Xtreme 250C). It helps the finish, protects the tool and also damps down the dust.
The finish straight off the mill is sometimes not too pretty but after a gentle rub over with fine wet and dry looks excellent. With a 5 thou tip I can cut very fine SMD tracking.
After the wet and dry, while the board has a bright clean untarnished finish, rub over with flux paste and then run a wide bit hot soldering iron quickly over the tracking while feeding fine solder to it. Once you have got the knack you can get a good tinned finish. Clean the flux residue off afterwards with thinners and then wash with Swarfega or similar hand cleaner to get a bright finish on the tin (yes I know it sounds weird but try it).
There is a lot more detailed waffle and pictures of my experiments at Woody's Workshop.
I hope that helps someone somewhere to get a working result.
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