The spindle bushings on my coil winder are too small to make larger diameter coils. If someone with a 3D printer can help me, I'd be glad to reimburse you. PM if interested. Sketch not to scale and length will be determined by angle, start and end diameters! No access to CAD so just roughed out the sketch.



If length gets too long the angle can be increased.

 

No takers?
Bump

 

Have you looked for a local public library or Makerspace that gives access to 3D printing?
https://virl.bc.ca/learn/skills/creativity-commons/3d-printing/
https://onlineacademiccommunity.uvic.ca/dsc/how-to-3d-print/

 

Nothing around here. Maybe in Savannah or Jacksonville but they are well over an hour away and I don't drive anymore since I lost the feeling in my lower legs due to neuropathy. Can't feel the pedals now. Maybe I can do the CAD and send it off...

 

I get 3D printing done in China. About $1 for the part and $30 for the shipping. I get extra parts because the shipping is the same for up to 20 parts.

What material? Plastic? Is the hole threaded?

Some of my winding machines have rubber pieces that look much like that. I made them from a rubber stopper.

I did not know I could get tapered stoppers so I made them from non-tapered stoppers. I put them in the drill press and get them spinning. Then remove rubber with sandpaper.

Search the internet for "tapered rubber stopper". I found some with a center hole like the middle one. The center hole can be made larger easy with a drill. It is a little hard to drill a hole where there is not a guide hole.

 

I can do the stl file (required by the 3D printer) and send it to you.
Or I can print two pieces and send it by snail mail.

 

No, the inside bore is not threaded. The material is plastic but somewhat soft but not as soft as rubber. Hadn't thought of rubber stoppers. We hand bored them in the lab with a tool that was a sharpened chromed hollow tube with a T-handle on the other end. It came as a "nesting" set of standard glass tubing sizes. ~6 to the set. Sometimes we needed stoppers with multiple holes and sizes.

@MrChips PM sent.

 

Get two cheap centering tool used to center the base plate in a router.
the bore will be 12.7mm (1/2") but you should be able to get a 7/16" to 1/2" bushing or just a few turns of black electrical tape - I assume you are not spinning more than 1k rpm.

Look at part number 45 in the second image to see the back side. The angle is steeper than what you asked for but I think the flatter cone is better because the two tips will hit each other if your core is thin with large I.D.

https://www.fix.com/parts/router/ri...ETVL2_3ZchvnF3Dvd-ZSUh8R54Mnz7BBoCx0gQAvD_BwE

 

I use rubber because I want good traction between the motor and coil. If the wire is large there is much pull on the wire.
In my case there is a toggle clamp on the shaft to add pressure on the coil.

 

I will get on it today.

 

No router. This is hand turned but the important piece to me is the counter. So, the RPM is very low. Typically using pasteboard or plastic tubing for the form and turning 100+ turns. Right now, I need to do 140 turns on a 40mm tube. I also thread a chuck on the end of the shaft to hold ferrite rods. There is a tightening nut on the shaft that compresses the bushings and the form workpiece to hold them in place. Exact centering is not necessary as it is hand wound as it turns to maintain tension and wire placement.

 

No router. This is hand turned but the important piece to me is the counter. So, the RPM is very low. Typically using pasteboard or plastic tubing for the form and turning 100+ turns. Right now, I need to do 140 turns on a 40mm tube. I also thread a chuck on the end of the shaft to hold ferrite rods. There is a tightening nut on the shaft that compresses the bushings and the form workpiece to hold them in place. Exact centering is not necessary as it is hand wound as it turns to maintain tension and wire placement.

I assumed it was not a router. My point is that a commercial, off the shelf product exists that you can use for your application at $3each. It is called a "centering tool" and is traditionally used to center the face plate of a router. You can use the same part with only slight modifications since the center is 1/2" bore instead of 11mm (7/16"). You'd need two of them to mount nose to nose.

 

Yes, very similar except the bushings I use are shortened in length by not tapering the entire radius. Your link is cheap! The ones I looked at were in the 25USD range each! Good idea except for the bore which can be fixed. The winder shaft only has ~5" of useable space. Anything longer than that either has to be hand done or use a far more expensive winder.

 

Yes, very similar except the bushings I use are shortened in length by not tapering the entire radius. Your link is cheap! The ones I looked at were in the 25USD range each! Good idea except for the bore which can be fixed. The winder shaft only has ~5" of useable space. Anything longer than that either has to be hand done or use a far more expensive winder.

You can append a new shaft to your current setup with a flex connector (I.e. Tyson tubing) so you don't have to perfectly align the shafts. As long as the count remains the same

 

There are also threaded couplers, although this shaft is probably metric. I need a thread gauge to be sure. Already thought about a shaft support like they use for long pieces in a lathe when using the chuck. I'll mod as need arises...

 

Ok, I got the bushings from @MrChips and was not surprised that they were too long for the spindle on my winder. No problem, get out the jeweler's saw and cut them down!


Cut each into 3 pieces and the middle pair perfect for the tube used.

Primary winding on the outside is 30 turns of 26AWG supported with wooden matchstick standoffs. Secondary winding is 140 turns with a tap each 125mm (~10 turns) and then 70 more untapped turns. Plus a few coats of conformal coating to keep it all tidy.

This is where I am headed except will probably use an LM386 amp to work around my hearing losses. I have a few 1N34 germaniums to start with and a 350pF single gang air capacitor (and a few others). More later...