Where to get 1/8" sheet mild steel laser/water jet cut?

[Ross77]

Very nice work, I'll be your first customer.. I want one

Just an idea but could you make up the thickness with laminations of thinner steel like some transformer chassis's, That way you can find the optimum thickness. Also if it was thin enougth could it then be pressed?

If some one can make the former I'll happilly press you out as many as you need. 10 ton Hydraullic press with foot operated pneumatic pump is very quick.

I relaise the production blade hotrails are much thinner, but remember this is to vibrate the string not pick up the vibratiuons...everything has to be beefed up.

Fair point. dose the tuning not suffer from the pull tho?

[HankMcSpank]

Very nice work, I'll be your first customer.. I want one

You'd be my second - on the strength of those ropey videos alone (which were for nothing more than showing my progress to a related Guitar forum) I've got an Italian chap who's taking a leap of faith & going to buy one off me (only because he's a niche requirement that can't be fulfiulled by existing commercial sustainer offerings!)

It's small beer at the moment (my hourly rate must be about 10p for what I'll be making vs the effort I've put in, but hey, from little acorns blah blah)

Just an idea but could you make up the thickness with laminations of thinner steel like some transformer chassis's, That way you can find the optimum thickness. Also if it was thin enougth could it then be pressed?

That's a reasonable proposal...and I'd considered it - but what's driving me towards 3.2mm more than anything is the availability of pre made Korean ABS 'blade' bobbins with an 1/8" 'blade' slot! (basicallly cutting bobbins on a dodgy homemade CNC takes forever...therefore if I'm ever to sell these in number I need a quicker way). It may well be that I can indeed go thinner, but additionally the blade needs a magnet on the bottom....& I need some amount of physicaly surface bottom area to attach the magnets to. (I don't have the luxury of normal pickup 'depth' to attach a hulking great ceramic magnet to as they do with blade pickups)

If some one can make the former I'll happilly press you out as many as you need. 10 ton Hydraullic press with foot operated pneumatic pump is very quick.

That's a fantastic offer - and I'd have to say a big high five to you all out there, for without one shadow of a doubt, this is the most helpful forum I've ever had the pleasure of being a meber of :clap:

As it goes, I don't know much about formers...how they're made., cost, limitations ...but it's something I'd pondered the other day & need to look into.

Fair point. dose the tuning not suffer from the pull tho?

Surprisingly no - because you're pulling & releasing in sympathy with the string's natural resonance.

Bye for now...

[BillTodd]

but what's driving me towards 3.2mm more than anything is the availability of pre made 'blade' bobbins in korea with an 1/8" 'blade' slot! (basicallly cutting bobbins on a dodgy homemade CNC takes forever

A friend of mine has had some success with 3D printed bobbins in his audio transformers. He had the prototypes made at Shapeways (from 3D models I made for him). Worth a look if you need complex shapes made in plastic as they only charge by weight and material (i.e. cheap-ish).

Bill

[John S]

Hank, Check your PM.

[Ross77]

I'm guessing John has a solution for you but........ Ive just had an idea for a quick fix........

Basically it involves using jigsaw with a fine blade and circle cuting attachment. If you can get the plate already in 55mm wide and say 500mm long then keep cutting blanks off as required. set the raduis to 9.5" to cut the radiused part and then square it off. quick buzz over a bench grinder wheel and job done. :dance:

P.S. how much do they cost?

[HankMcSpank]

Hi Ross,

Thanks for the idea...it's a good 'un!

re having a solution...john was offering to get my part into a larger quote request he was submitting into a laser cutting Co ...but I need more testing with this blade version so will miss that particular landing slot (previous versions have use individual pole pieces)

[Ross77]

Hi Hank
How much of a rush are you in, I'm sure I could make you batch of 10 or 20 next weekend. Ive just drawn the 240mm radius over 55mm width and its only 2mm. So with the band saw I can cut the rectangular blanks and then I'm thinking that with a radius jig mounted on the bench grinder the raduis can be ground, which would also give a nice finish as this will be the visible bit.

[HankMcSpank]

Hi Ross,

I really appreciate your offer of help - but I wouldn't dream of putting anyone to that trouble!

As I explained to John via PM, I'm trying to stay one step ahead (so that when I arrive at a given point I already have the info I need!), so wrt pursuing the blade idea, I realised I'd need a quote to get them made properly. I don't actually need them made immenently, as I'm still very much in the 'proving' phase.

As it goes, after further (heavy) testing over the past 4-5 nights (using a rough 1/8" thick rectangular bit of mild steel) I've found that a 'blade' in a sustainer driver bobbin is sub par vs inividual guitar string 'pole' pieces. This is worrying ...I was just about to place an order for a few hundred blade bobbins from Korea! (presently I cut every bobbin I make on my CNC from acrylic - pain in th @rse!) ...I'm hoping it's just the variant of steel I bought (I wanted black steel ...but couldn't find any in a suitable 'hacksawable' size ....so I bought bright steel, which apparently - and I'm no steel expert - has more carbon in it?). If I place magnets at the bottom of the blade & then touch the other side (top) with a screwdriver, there isn't much magnetic pull - whereas when I do the same using pole pieces (mild steel grub screws) the top of each pole piece has a decent magnetic pull.


Two possible solutions...

1. Try a different grade of steel for the blade.

2. Crank up the strength of the magnets I'm attaching to the bottom of the blade (this would mean putting physically bigger magnet on there...and I don't have much room to do so)

So for now, I'm still, stuck in 'uncertain' land wrt blade type drivers.

I appreciate the offer of help though - many thanks.

[ptjw7uk]

Not sure what you are ultimately trying to accomplish but putting a magnet one side of a steel bar will effectively short out the magnet, so I would not expect to get an awful lot of magnetism on the other side.
If you want the magnetism to pass through as it were they would need to be isolated a bit to channel the effect as in transformer laminations which are effectively insulated on one side such that the magnetic effect is channeled around the laminations and not leaking out the sides.
I think you need more design input.

Peter

[Ross77]

I think Peter has beaten me too it but I was going to suggest using a thinner piece of steel, I dont know much about magnets but maybe a lower mass is required, as I said before the hot rails type of pick up use two thin strips, maybe this isnt a coincedence

Maybe you can create a sandwich of plastic and steel to make up the 3mm width?

Why do you need a blade anyway? is it cosmetic or are there dead spots between the poles?

Anyway good luck