Here is a list of all the postings IanH has made in our forums. Click on a thread name to jump to the thread.
|Thread: Looking for a Sharpening Service for End Mills & Slot Drills please|
My last lot cost between £3 and £10 each depending on the size of the cutter. Vat on top I guess.
Raynor Toolservices in Market Drayton raynortoos.co.uk - about once a year I send them a mixed bag of milling cutters with instructions to grind to the next imperial size down and they come back individually boxed up and labelled having been CNC ground.
|Thread: Delapena External Hones|
I recently acquired a pair of Delapena external hones, one small and one large. Some of the stones are in poor shape and I would like to sort them out.
I understand that these tools are no longer made so I am looking for replacement abrasive stones assuming I can remove the existing stones from the holders and glue in replacements.
The stones are numbered 11 to 15-P8-F for the bigger tool and 3 to 6-P8-F for the smaller one. Looking at the Delapena Web site I think F denotes silicon carbide but I can't see anything to decode grit size.
The hones will be used on decent steels, En16, EN24 and case hardened EN36B for example.
The bigger stones are 2" long 3/16" wide and 1/8" thick, the smaller ones are 3/4" long by 0.1" Square.
The existing holders could be modified to suit stones of a different section assuming I can cut the replacement stones to length somehow.
I have emailed Delapena to see if they have any info or suitable stones, but I thought I would ask the forum at the same time as someone is bound to have done this already or will have some good ideas.
|Thread: Laser or water-jet cutter who hold stock of spring or tool steels|
Give these guys a call **LINK** they cut some spring steel steering wheel spokes for me some time ago.
|Thread: DIY tool holder for inserts|
Here is the tool holder finished (probably). It is a bit like a boring head but cruder in that it is set to a gauge rather than having a micrometer screw, also it needs to show a concentric bore on the bottom at all times to allow a pilot to be mounted which locates in the valve guide, hence the horseshoe shape.
The pocket for the insert was machined on the CNC machine. I glued the insert in as suggested, then clocked up the hole in the tool. I moved 3 thou toward the back of the tool holder, and drilled and tapped M3. The result was terrible for some reason and I ended up soft soldering some shims in the pocket to sort it out. Not sure why it went wrong, I suspect the tapping size hole drilling was not stiff enough somehow..... I will try harder next time.
Thanks for these answers, very reassuring to hear. The mounting screw is M3 so it looks like 3 thou offset toward the shoulders should do it.
I am working on a tool holder to mount commercially available inserts to machine multi angle valve seats.
I have made the basic tool holder based around standard Serdi pattern tooling, but have not yet decided on the specific insert type. The two options I am considering will both have a pocket with two shoulders for the insert to locate against. In both cases the inserts are held in with a standard looking countersunk torx screw through the insert
My question is to do with the location of the tapped hole for the screw. I have the impression, based on some of my existing commercial tooling, that the position of the screw may be biased a little toward the shoulders rather than being truly Concentric with the hole in the insert. Nipping the screw up gives the impression of the countersunk part of the screw going home and jamming the insert into the holder.
The question then is, should the screw be biased toward the shoulders or not, and if so, by how much?
|Thread: Moving a Bridgeport|
My Bridgeport came in to my back garden workshop over the house with the help of a 35 Ton crane. The crane operators were fantastic, putting the machine down at the workshop door with tremendous precision.
|Thread: Moving Workshop Equipment|
Having moved my fair share of machines around over the years, the need arose to move a J&S 1212 cylindrical grinder from Flixton near Manchester to Middlewich. Although it is not a particularly big machine, the grinder is probably on the heavy side compared with things I have moved in the past. I briefly considered hiring a trailer and having a go myself with the help of friends, but in the end made contact with Steve at Landylift.
The move was accomplished without drama this morning with Steve’s very professional assistance. As well as being a thoroughly nice guy, Steve is very capable and comes fully equipped with a crane and plenty of lifting gear.
If you are considering moving machinery anytime soon, rather than take any risks to yourself or the machinery, I would thoroughly recommend Landylift.
|Thread: What do you use for heat treatment?|
Just picking up on the stainless foil comment. When idly exploring the idea of building a vacuum heat treatment oven in order to avoid scale, I came across the idea of putting a small piece of (brown) paper in the foil envelope along with the part. The idea is that the paper burns early on in the process and consumes any oxygen that there is in the envelope this avoiding oxidation of your component. The vacuum heat treatment oven didn’t get built.
i have a small gas lab type kiln in my workshop. It has been most useful for silver soldering when you have to silver solder something small onto something very big. With a gas torch it can be a struggle to get the bigger part hot enough without the smaller part getting too hot and killing the flux. Everything comes up to temp together in the oven.
|Thread: Q-cut instructions|
I have a couple of Q cut parting off tools as well. Has anyone identified a source of replacement tips now the Greenwood tools are no longer trading?
|Thread: Single point tool to cut an internal 5/8-10 LH ACME thread|
Carmex do a miniature 10 tip ACME insert, I had a quick look but couldn’t spot a specification stating how small a thread you could cut but 5/8” is not so small. I use Carmex miniature and sub miniature threading tools for normal threads and they are pretty tiny.
|Thread: What is it|
I found it illustrated in the Vintage Motorcyclists Workshop - it would appear to be for cleaning valve guides and could be had as part of a set of wire brushes.
|Thread: Seal selection|
i remember at the time a discussion with the folk at Luminition about the size of the chopper. I recall that the leading edge puts power on the coil and it is the training adage that triggers the spark. The width of the chopper then determines the dwell angle and the duration that the coil is powered up. Too long a dwell angle could lead to the coil overheating. The Morgan engine is pretty slow revving by comparison with modern stuff so a small dwell angle would be fine. We decided to start with the chopper shown in the photo and then reduce it if we hit problems. It never got changed!
the electronic magneto has a 180 degree dwell angle, even more extreme. The reason for trying 180 degrees was that if it worked, we could reverse the direction of rotation of the magneto with the same 180 degree ring magnet. Reducing the dwell (bringing the N and S poles of the ring magnet close together) would mean that the ring magnet would have to be turned upside down if the mag was to run backwards. I ran the mag on the lathe at low revs for half a day in the warm workshop to see if it did overheat - it seemed fine so we are road testing with the 180 degree dwell.
I converted my own 1933 coil ignition Morgan to electronic ignition something like 20 years ago. The set up I used was from Luminition and was based on a kit provided for Moto Guzzi motorcycles. The through beam infra red units fit neatly to the contact breaker housing, I made one IR unit fixed and arranged for a bit of adjustment on the other to fine tune the timing on No 2.
The magneto contact breaker housing is smaller and I suspect you would struggle to get the hard wired Luminition through beam units in. If there was a PC board mounted equivalent through beam unit it would be a nice solution. Do you know of a suitable component?
There is a cover for the bevel gears and oil pump drive, here is a close up. You can also see the mag end cover in place.
There are plenty of magnetos around where the defunct magneto becomes simply a housing for a set of points. You then you have coils, or a double ended coil tucked away somewhere under the bonnet. The original magneto HT leads are either removed or tucked away somewhere, and the working HT leads from the coil(s) emerge from under the bonnet. This works but loses something in terms of authenticity.
The objective of this project was to develop a magneto that was indistinguishable from the original instrument. This means that the magneto HT leads must be real. The unit must be completely self contained, there can be nothing mounted remotely, and you can only have one wire (the original only has an earth wire) going to the magneto. The original cable advance/retard control must operate as normal. An extra rule I added in was that the double ended coil/wasted spark approach would not be used - it has been associated with carb fires on these engines.
So we have two separate coils inside the magneto body, the secondaries essentially hard wired to the HT pickups - so no distributor and no carbon brushes. There is also a PC board tucked away inside the magneto body with two more or less independent ignition circuits. A relatively small diameter shaft driven by the standard bevel gear passes between the coils and through a hole in the centre of the main PC board. The shaft terminates in the points housing.
The single wire is used to provide 12 volts from the ignition circuit.
Inside the points housing is a dummy cam ring which provides a mounting for the trigger PC board. The manual advance retard control engages with the dummy cam ring in the normal way. The trigger board provides mounting for two Hall sensors, one for each circuit. Each sensor has an associated LED indicator light to allow you to time the magneto. The Hall sensors are mounted on the PC board, separated by an angle chosen to suit the V angle of the engine. On the end of the shaft is a taper on which is mounted a component with a ring magnet that presents N and S poles to the Hall sensors.
To time the magneto, you mount it on the engine without worrying about timing, you just engage the bevel gears. You set the manual adv/retard to max advance and then turn the engine to the appropriate firing point for No 1 cylinder. You then rotate the ring magnet until it just fires No 1 (the LED indicator facilitates this). You nip the ring magnet holder up on its taper, fit the cover and then drive off 😃.
Happy to have a chat about your set up - send me a pm If you would like to have a natter.
The mag will be lucky to see 3000 rpm on this sidevalve, and would most likely only see it momentarily before something catastrophic happened 😬, but some or the more exciting ohv engines will rev up to 6000 rpm and even a bit beyond. A rev limiter can be programmed into the mag if required to look after the engine.
The electronic mag is designed to run clockwise or anti-clockwise, and by changing the discrete timing board mounted in a dummy cam ring, it can handle different engine types with different V angles.
Just for interest, here is the magneto on the test car, a 1930 Family Morgan 3 wheeler. Yet to fit the cover over the bevel gear drive and fit the points cover.
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