My Latest Project

[HansiRowe]

Very nice work Alex… it's a beauty!

[alex_holden]

Thanks Hansi!

[SteveS]

I thought an ultra-small miniature with a button on each end. Anglo system with 4 notes.

Edited October 19, 2014 by SteveS

[Geoffrey Crabb]

I thought an ultra-small miniature with a button on each end. Anglo system with 4 notes.

Copied from another Topic.

I suppose, my late brother Neville and I could claim to have made a Nanoature in 1983.

This was a novelty device (I won't call it a concertina) made for a French comedy musical act (not a clown). The requirement being for something 'pocketable' that could replicate the siren of a passing French police car.

The resultant 1.75 " AF square 'device' (See note below) had one button at each end, was 'bisonoric' and double reeded. To provide reasonable sustain of individual notes, a ten fold bellows was fitted.

To provide the necessary doppler effect, the reeds on the right were tuned F# (pull), D# (push) and those on the left F (pull), D (push) . Each pair of the four pairs of reeds fitted were tuned wet to give the characteristic French siren sound.

In use, the right button was held down whilst the bellows was expanded and compressed, the effort being gradually increased to simulate the vehicle approaching. At the appropriate point, the right button was released and the left button then held down, the effort on the bellows being then gradually reduced to simulate the vehicle passing and into the distance.

Note, due to the small bellows components, 2 inches across the flats is the minimum for a hexagonal bellows, until proven wrong

Geoffrey

[Frank Dudgeon]

Alex,

 

Between your marionettes à la planchette and your creative doorbell adornment, I am so impressed by your creativity and crafting skills. I'd tug at my forelock if I still had one.

 

Frank

[Dana Johnson]

Think stainless was a good choice if you want to keep it bright. Lacquering brass just seems to be fighting its natural tendency, better to let it develop a patina, or apply a treatment to hasten the process. One thing I've done which helps in sawing stainless is to coat the back side with bees wax ( just melt it on ) when the blade cuts through, it picks up a little wax which melts from the heat of the blade and lubricates it making it cut better and stay sharp longer. No Stainless alloys are really fun to machine, but for drilling, use cutting oil or lard oil or the afore mentioned bees wax or stick lubricants to lubricate the cutting edge. Use constant downward pressure to keep the bit cutting. ( with quick backing off to remove chips in a deep hole but never dwell at the bottom. If the bit is not getting a decent chip, it work hardens the stainless which can then be very resistant to further cutting and will dull and burn the bit in a flash. If you keep the right machining conditions, you can get a lot of mileage out of a small drill bit, even in stainless. Glad you didn't give up. Well worth the effort.

Dana

[alex_holden]

Thanks Frank and Dana!

 

Regarding drilling the 1mm pilot holes, I think work-hardening was definitely a problem. In hindsight centre-punching may have hardened the surface enough to cause trouble for HSS bits. In the end I switched to solid carbide (re-sharpened PCB drilling bits from eBay). They cut through the stainless fine but they are extremely brittle and have a tendency to catch and snap as they break through the back of the workpiece (I broke three of them that way). I also blunted one by accidentally trying to drill through a fragment of carbide that was stuck in the bottom of a hole.

 

My initial bright idea for lubricating the saw blades was to impregnate the paper template with beeswax furniture polish. Bad idea. It caused two problems: dirt stuck to it (the sawing produced fine black dust), eventually obscuring the lines so badly I couldn't see them properly, and it weakened the glue so the paper tended to come unstuck at any sharp points (most of the mis-shapen points are because I had to cut them blind while a loose bit of paper flapped up and down with the blade).

 

I initially used Vallorbe saw blades, which are supposed to be really good and which have worked fine for me in the past on silver and brass. Unfortunately they don't seem to be hard enough for stainless steel: they often go blunt within a stroke or two. I switched to a different (slightly cheaper but also Swiss) make called 'Razor Brand' and had much more success, though they do still go dull fairly quickly. Once they go dull you have to push harder to get them to cut and that makes them more likely to break. Towards the end as my technique was improving, I was getting about one and a half piercings out of a blade.

 

I'm planning to make at least one more of these by hand to build on what I've learned.

Edited October 20, 2014 by alex_holden

[Rod]

Alex, You are obviously having a lot of fun with this project. I hesitate to mention that the piercing on the steel ends of my Anglo, whilst clearly based upon traditional design, were apparently totally achieved by routing. No doubt this would be considered unacceptable to a purist but to my eye it is just as effective and attractive. The ends were finally chrome plated and look very smart. A router will of course always leave rounded profiles but I guess a router of suffient precision would have the ability to reduce these to be barely visible to the naked eye ? (Perhaps another alternative is acid etching. ?)

[alex_holden]

Thanks Rod, another possibility which I definitely intend to try at some point is CNC laser cutting. I believe it should be possible to achieve good results with reasonably sharp inside corners (the beam diameter is something like 10 thou). I've no idea what it's likely to cost though. The point of this project for me was to learn the skills involved in designing and cutting metal ends by hand.

[DDF]

Alex,I find using cobalt drills(not coated) with some cutting fluid works well for stainless.David.

[alex_holden]

I'll give cobalt a try, thanks.

[HansiRowe]

Hey Alex… why stop with the front door bell…! One of these could be your next project!!

 

"The 33 houses in the clearance area comprised six blocks. Five were hexagonal in plan, a shape which was responsible for their being popularity (but unofficially) known in the locality as “Concertina Cottages.”

 

 

 

[Chris Ghent]

Slow speed is essential...

[Bill Crossland]

While I admire anyone who has the patience and strength of wrist to tackle the making of new ends, as Alex says, laser cutting is far easier.... The attached picture shows a nickel silver Jeffries pattern replacement end after cutting and before the crimp and polish, together with a door bell blank in thin stainless. The drawing takes a couple of hours, the cut less than a minute....the technical drawing for the ends is the harder part, but nothing like as stressful on body parts as sawing.....

 

The Jeffries end will go onto an instrument shortly, the door bell will languish in the concertina workshop forever.....

[Don Taylor]

I'm with Bill on using a laser cutter, but I can understand the satisfaction of DIY.

 

But look at this: https://www.youtube.com/watch?v=PlF_oXvbu4s

 

Anyway, I have been restoring boats for a while and that involves a lot of drilling into stainless steel. A few things I have picked up along the way:

 

I only use sharp cobalt bits.

 

I use a cutting/cooling fluid or wax. I prefer the wax as it is easier to apply.

 

Drill a test hole first to make sure that your set-up is correct.

 

Use a drill press at its slowest speed, sadly the smallest presses often run too fast. You can only get sufficient, steady pressure and keep the drill bit at 90 degrees to the surface with a drill press. When using small bits ( <1/8") I often break bits if drilling by hand, bigger bits are not so bad.

 

Use a vice or a clamp. I really like using a machinists vice because you can position your work piece accurately.

 

Press hard while drilling most of the hole, but when you are almost through reduce the pressure for the last bit so that you do not force the drill bit through a half drilled hole. The bit will stick in the hole and stop the drill press or break the bit - or fling your work piece at you if you are trying to hold it in place with your hand.

 

A drill bit works like a planer, not a grinder. So, like a planer, it has to be really sharp. If everything is set up correctly then the bit will easily and quickly drill through stainless and the swarf should come out as a long spiral. It it does not spiral out then something is wrong - too fast, not enough pressure or the bit is too blunt. Do not press on as you will work harden the stainless and then you will have a devil of a time, and use up some drill bits, making your hole. If your drilling rig is set up correctly then the s/s wont get hot because you are slicing the metal away, not grinding it. Your drill bits will last longer.

 

When drilling bigger holes, use a step approach. Start with a sharp 1/8" and drill a complete hole, the step up with successively larger sizes of bit until you get to the size you want. If you use this approach then your larger bits do not have to be so perfectly sharp as you are not asking them to to work so hard. The small bit does have to be sharp. I buy packs of 12 1/8" bits and discard a bit as soon as it shows signs of not cutting easily. I can sharpen larger bits, but I have never managed to sharpen a 1/8" bit, or smaller, enough to drill stainless.

 

Somebody mentioned using router bits to cut shapes. I have never tried that, but good router bits are expensive and I think that they are only intended for wood? I would try a machinists end mill which is designed for this job. http://en.wikipedia.org/wiki/End_mill, but I am a bit leary about holding the metal being cut because there is a lot of power in a drill press motor.

 

It goes without saying that very good eye protection is needed for this kind of work.

[alex_holden]

Thanks for that Don. I haven't yet tried Cobalt bits. I've drilled 2mm (about 5/64") holes in stainless steel with sharp HSS bits without much trouble. The difference this time was that the holes were only 1mm diameter (slightly over 1/32"). At that size the bits are very delicate, and you can't apply much force before they deflect and break. The solid carbide bits are harder and better able to cut through work-hardened stainless without going blunt (I suspect centre-punching before drilling hardened it), but they are much more brittle than HSS. The slightest catch as they break through the back of the work and they shatter like glass. They are normally used with CNC drilling machines that lower the bit into the work at a constant rate.

 

I also have trouble hand-sharpening bits smaller than about 1/8". I had a go with the 1mm HSS bits but the results were hopeless.

 

Interestingly the point of a fluted twist drill doesn't actually cut the metal, it rubs and pushes it outwards until it reaches the cutting edges.

 

(BTW I drilled 40 holes with the 1mm carbide bits and broke three of them in the process.)

Edited October 21, 2014 by alex_holden

[Geoff Wooff]

I drill a lot of small holes (1.2mm) during the making of my instruments (Uilleann Pipes) and have found that my biggest culprit for drill bit breakage was wear in the rack and pinion of my drill presses. As the drill bit starts to break through the far side of the hole the weight of the quill shaft and chuck acts to speed up the downward movement as it takes up the slack, the drill bit bites too hard and I spend time and effort extracting the broken fragments from a nearly finished part.

 

These cheaper Asian made machines are very variable and the last time I bought one I searched through all the local tool shops untill I found a display model that had no slack in the rack and purchased it " no I don't want a shinny new one in a box... I'll take this one , thankyou!" Needless to say the slack bagan to appear after only a few months!

 

I now have a small "model makers" drill press ( by Proxxon) which has greatly reduced bit breakage.

 

Alex, are you intending to use Stainless Steel for the Ends of a Concertina ? I can see that material's usefullness as a Door Bell suround but I'm not sure I like the idea of using it on an instrument, though I notice that Wim Wakker uses it for his metal covered Buttons.

Edited October 22, 2014 by Geoff Wooff

[alex_holden]

I'm currently using a Minicraft drill in a stand like this one:

http://www.naturecoast.com/hobby/mb540.htm

 

The biggest problem with it is the return springs on the stand are too strong, so it's difficult to feel how much pressure you are applying to the bit. I have used it to drill many 0.6mm holes in sterling silver for cut-coin jewellery work, but that is really tricky (if you see the bit start bowing, you are pushing too hard!). I don't think I have ever managed to drill a hole smaller than 0.6mm with it because the chuck/bearings have too much runout. It's far from ideal but it's what I have available right now.

 

I do have a better quality sensitive drill press in storage waiting for when I am able to set up my permanent concertina-making workshop. It's a vintage machine that is designed to be driven by a round leather belt, so I'm thinking of hooking it up to a variable speed sewing machine motor.

 

For instrument ends I'm planning to use nickel silver. The bell push is stainless steel for weather-resistance.