Minipulse Plus Rev My time has come!

[mushaba]

After some quallity time with Autocad and my cnc i finally have the coil cores made from PE plastic..My concern at this moment is that the core is 2,5mm thick not 0,7-1,5mm as instructions,i couldnt find at local market PE this thin...Hope it all works out well

[dbanner]

Brilliant work. The shield for these coils maybe better by painting the walls of the coil housing.

[mushaba]

Something is wrong




I've started winding at inner slot,3 out 3 in,after 5 full turns i entered again from the slot i began,moved 4 upper slots and so..

[kt315]

read my comments https://www.geotech1.com/forums/show...l-for-baracuda
you must do A TRANSFER STEP after every one layer.

[mushaba]

read my comments https://www.geotech1.com/forums/show...l-for-baracuda
you must do A TRANSFER STEP after every one layer.

Sorry,my bad,i did not transfer 1 slot every 5 turns...grrrrrrrrrrrrrrrrr...I hope it worth it

[mushaba]

Brilliant work. The shield for these coils maybe better by painting the walls of the coil housing.

Brilliant was the guy who designed it originally,im just a "copier"...Turns out that design it to cad and make 3 of them was good because unwound the mistaken ones is hopeless....If my PTFE comes in time i will make a nice "vacum" formed housing,as for the shield as i said before i must be doing something wrong because everytime i try to shield i loose detection depth.

[mushaba]

The "failed" one i can use it as AM radio antenna

[kt315]

Sorry,my bad,i did not transfer 1 slot every 5 turns...grrrrrrrrrrrrrrrrr...I hope it worth it

also, big mistake people are filling the coil by epoxy. DO NOT DO SAME -!
do a layer above by a rope diameter 3-5mm with a step 5-10mm . after that do 2-3 layers of skotch standart tape.
internal area with the winding has to be isolated (airy) and epoxy does not have to fill in it.
do shielding, graphite aerosole, layer inside your housing. melt a naked thin wire (i use silver covererd wire)
in surface of your graphite layer. you have to connect ground wire of the cable to it on end of job before finish epoxy filling.

[mushaba]

It is my first time to such complex coil build,didn't notice little crucial detail such the one slot moving after 5 turns each time...At 25 turn I still moved one slot forward,instructions said front or back...ETFE cable 0.64mm I think.Im going to test it on Saturday,hope I nailed it!

[dbanner]

That looks really good. Now you know why I stay away from such coils.

[mushaba]

That looks really good. Now you know why I stay away from such coils.

Yes, indeed dbanner!But desperate times requires desperate measures....Can you suggest me a good spec monocoil?

[godigit1]

Hi Mushaba,
Nice job on the coil and forms. Your Idea about the flat coil and using your mill to make a form is very interisting. I was wanting a desktop mill for some carbon fibre work but havent sprung for it yet.
I would think a wire width spacing would be good for your form and maybe two sided where the wire wraps around the inner or outer diameter and the wires line up in between the opposing wire layer.
Ive played with a few flat coils but they werent too good due to wire type next one will be DD. A form like your thinking would be perfect.

[green]

Flat spiral and flat basket I posted awhile back. Coil capacitance less than 1foot of lead wire. Don't seem to need spacing between wire wraps to reduce coil capacitance. Maybe another reason to space wraps?

[mushaba]

Hi Mushaba,
Nice job on the coil and forms. Your Idea about the flat coil and using your mill to make a form is very interisting. I was wanting a desktop mill for some carbon fibre work but havent sprung for it yet.
I would think a wire width spacing would be good for your form and maybe two sided where the wire wraps around the inner or outer diameter and the wires line up in between the opposing wire layer.
Ive played with a few flat coils but they werent too good due to wire type next one will be DD. A form like your thinking would be perfect.

Hi godigit1,thanks for your reply!I was blessed in my life with lot of workspace,that gave me the comfort to collect tools year by year and make a workshop for my hobbies!Except the electronics which is my main job I'm a machinist wannabe,I have a lots of tools about turning paralleling drilling and welding..The cnc mill came due to electronics need for prototyping,it's a good way to assemble a pcb and if is all good you print it professionally,lots of pcb manufactures with great price.I would suggest if you are thinking about building a cnc Just do it as Michael Jordan said,it will give you a lot of "freedom" and flexibility..The mechanical and the electronic parts now days costs few hundrends,learn a cad program and you are ready to go!
Today a friend send me a copy of Inside The Metal Detector,man all the knowledge in there!!!I will try to read it before I decide about a spiral,it's good to experiment but is better to construct something with correct design if you know the physics behind that...As I understand the time that the coil "diggests" the spikes from the mosfets is how fast the coil is...The flat spiral should reduce capacitance due to wire spacing but what is the formula to decide what spacing should use?If you have anything I'm mind I will happily construct and test it.I am missing a good working coil to have as base to test my current MPP project and Mirage and Delta Pulse to come...But I must have a base and a correct coil is the thing I need right now.

[mushaba]

Flat spiral and flat basket I posted awhile back. Coil capacitance less than 1foot of lead wire. Don't seem to need spacing between wire wraps to reduce coil capacitance. Maybe another reason to space wraps?

Thanks green for your reply!
So spacing between the wraps won't reduce capacitance?Did the coil you show work well?