Hiow to mount bobbin to shaft?

[ReWind]

Hey fellas. Long time listener, first time caller here. First, thanks to everyone for the existence of this forum. I've picked up a bit of knowledge here already.

I've been working on a winding machine and have come to a sticking point. I have a turning shaft that's about .64" wide (with a flat spot for set screws if needed) that I need to mount my bobbins to. I'm having a little trouble finding a prefabricated part (or combination of parts) that I can use as a "base plate" for the bobbins. I see some of you have nice machined aluminum discs, but I don't have the tools to make one of those at my disposal.

I could use an adapter shaft coupling to convert the shaft size if I can find something suitable to couple to it. I have thought about using a large collar mounted to the very end of the shaft to make a large flat surface to fix the bobbin to but I have not found one with a very large OD.

I'm looking for some ways that I might mount a bobbin to my machine's shaft without custom machining a part?

Thanks so much!

[ReWind]

Guitar pick up tooling mandrel for CNC Winding Machine | eBay

Something like the above link would work, but it's awfully expensive for a mount that can only do one pickup type.

[David King]

So you have a .640 shaft? That's not a very common drill size. I'd cut a 3-6"disc of plywood and drill a 5/8" (.625") hole through it and enlarge that carefully with Dremel tool (sanding drum is good for this). Get it on straight and epoxy it to your shaft with PC7. If you want to make it removable just put a little car wax on the shaft first.
If you have a tablesaw you can mount the disc on that and true it first with a sanding stick with the blade guard removed.

[kayakerca]

Hey fellas. Long time listener, first time caller here. First, thanks to everyone for the existence of this forum. I've picked up a bit of knowledge here already.

I've been working on a winding machine and have come to a sticking point. I have a turning shaft that's about .64" wide (with a flat spot for set screws if needed) that I need to mount my bobbins to. I'm having a little trouble finding a prefabricated part (or combination of parts) that I can use as a "base plate" for the bobbins. I see some of you have nice machined aluminum discs, but I don't have the tools to make one of those at my disposal.

I could use an adapter shaft coupling to convert the shaft size if I can find something suitable to couple to it. I have thought about using a large collar mounted to the very end of the shaft to make a large flat surface to fix the bobbin to but I have not found one with a very large OD.

I'm looking for some ways that I might mount a bobbin to my machine's shaft without custom machining a part?

Thanks so much!

Have you considered cutting a 4" acrylic or hardboard disk and mounting it the shaft collar similar to the technique detailed in Jason Lollar's pickup winder book? The shaft on my winder in progress is .625 (5/8") and the shaft collar is 1/4" thick. There was plenty of room to drill and tap the face of the shaft collar to accept 3 6-32 machine screws to secure the bobbin faceplate to the shaft collar. When my faceplate mount was complete it was only .004" off true without any shimming. You can drill a small hole (with a small countersink) through dead centre of the faceplate to accommodate a 1-1/2" 4-40 machine screw that you can mount Strat and Tele bobbins to through the centre hole in their flatwork and secure with a caul and a nut. For other bobbins such as a P-90, you could drill 2 holes that line up with the hole spacing in the bobbin and mount in a similar fashion.

Here's a picture of my winder in progress at an earlier stage where you can see the mount plate setup a bit.



Anyway, this is along the lines of the (garage style) Jason Lollar winder and not a CNC machine type precision winder setup.

[ReWind]

Fantastic ideas! Thanks to both of you. I was thinking about an acrylic disc. If I can find one pre-made, I can take care of the center hole and screws for mounting various bobbins.

Do you think it's possible to drill and tap an acrylic disc to accept a set screw to lock the disc to the shaft? If not, I will do as suggested with mounting it to the side face of a collar.

Thanks again. I really appreciate the help!

[kayakerca]

Fantastic ideas! Thanks to both of you. I was thinking about an acrylic disc. If I can find one pre-made, I can take care of the center hole and screws for mounting various bobbins.

Do you think it's possible to drill and tap an acrylic disc to accept a set screw to lock the disc to the shaft? If not, I will do as suggested with mounting it to the side face of a collar.

Thanks again. I really appreciate the help!

I'm not sure what you are asking for the drill and tap of the acrylic for a set screw. Are asking if you could drill it from the outside edge, in 2" to the shaft? Can't see that working very well. Yes you can tap acrylic, but it would strip in short order would be my guess. I would use threaded inserts, either 6-32 or 4-40 to hold a screw into the acrylic. Here is an example of acrylic circles from ebay, I actually picked some up at a local shop that sells plastics.

acrylic circle 1 4 | eBay

[ReWind]

Ya, that's exactly what I meant, tapping in from the side of the acrylic. Stripping was my fear too. Probably easier to mount to a metal collar. eBay wins again! Thanks.

[David King]

Acrylic actually holds threads just fine but as Jim says the 2" hole depth from the rim will not work. You can glue a smaller acrylic disc to the larger one to use as a collar. Again your main problem is the .640" shaft size, can you cut the shaft shorter -back to where it's a more standard size? Either that or take it to someone with a lathe who can turn it down to an even 5/8".
I can machine a custom collar for you that's got a .640 hole in it if that's your only way forward, just send me a PM but double check those dimensions first...

[ReWind]

I've ordered two 5" x 1/4" acrylic discs (in case I screw one up or just decide I need another) from eBay and some of the two piece collars below from McMaster. The shaft on this machine measures 0.639 on the caliper (weird, I know). Just a hair over 16mm, NOT measured on the flat side. I think with the flat side allowing a little slack, the 16mm collar should fit and give me enough meat on the sides to affix the disc to. If not, I can possibly use an 18mm collar and a gasket of some sort or turn the shaft down on a lathe as you suggest.

[kayakerca]

Acrylic actually holds threads just fine but as Jim says the 2" hole depth from the rim will not work. You can glue a smaller acrylic disc to the larger one to use as a collar. Again your main problem is the .640" shaft size, can you cut the shaft shorter -back to where it's a more standard size? Either that or take it to someone with a lathe who can turn it down to an even 5/8".
I can machine a custom collar for you that's got a .640 hole in it if that's your only way forward, just send me a PM but double check those dimensions first...

Machining to 5/8" seems like a lot of work when a 5/8" mandrel is only $18.00.

G5547 Bench Mandrels - 5/8", Bronze Bearing

With this inexpensive mandrel, you can use a stock 5/8" shaft collar which easily drills and taps for 6-32 machine screws to hold the faceplate. The problem with glue the faceplate to the shaft collar (either acrylic or a metal one) is that you cannot shim between the collar and faceplate if it does not run true enough.

David, I'm honestly am impressed that you have the tools for that type of work. My cool tools top out at General International floor standing drill press with a 6" travel.

[big_teee]

Machining to 5/8" seems like a lot of work when a 5/8" mandrel is only $18.00.

G5547 Bench Mandrels - 5/8", Bronze Bearing

With this inexpensive mandrel, you can use a stock 5/8" shaft collar which easily drills and taps for 6-32 machine screws to hold the faceplate. The problem with glue the faceplate to the shaft collar (either acrylic or a metal one) is that you cannot shim between the collar and faceplate if it does not run true enough.

David, I'm honestly am impressed that you have the tools for that type of work. My cool tools top out at General International floor standing drill press with a 6" travel.

Are you using the Grizzly Spindle Assembly?
I like the looks of the 1/2" all Ball Bearing Job.
Does everything in the Picture come on it?
B_T

[kayakerca]

Are you using the Grizzly Spindle Assembly?
I like the looks of the 1/2" all Ball Bearing Job.
Does everything in the Picture come on it?
B_T

The picture in my first post is the 5/8" mandrel I bought from Grizzly. It comes with everything you see in the picture in the link (including the 2 5/8" shaft collars), but it is not the ball bearing unit it is a sleeve type bearing. Left hand thread on one end and right hand thread on the other. I have cut off both ends at this point. The 1/2" model is $15.95.

G5546 Bench Mandrels - 1/2", Bronze Bearing

I think either is a pretty good deal.

[big_teee]

The picture in my first post is the 5/8" mandrel I bought from Grizzly. It comes with everything you see in the picture in the link (including the 2 5/8" shaft collars), but it is not the ball bearing unit it is a sleeve type bearing. Left hand thread on one end and right hand thread on the other. I have cut off both ends at this point. The 1/2" model is $15.95.

G5546 Bench Mandrels - 1/2", Bronze Bearing

I think either is a pretty good deal.

G5548 Bench Mandrels - 1/2", Ball Bearing
This is the one I was talking about.
Not a bad deal.
T

[kayakerca]

G5548 Bench Mandrels - 1/2", Ball Bearing
This is the one I was talking about.
Not a bad deal.
T

Agreed.

[ReWind]

Well, the 16MM collar mounted to the shaft fits and should work well! I should have the acrylic discs any day now.

I've realized while taking this winding machine apart yesterday that the main shaft's bearings are in terrible condition (I thought the resistance I felt was just due to the gearing, but with all gears disengaged, the shaft doesn't exactly spin freely). I might have to figure out how to pull the bearing casings and replace those as well. ...and as a result maybe replace the shaft itself, as it seems to be a non-standard size. Geez. Kinda tempting to just start over with one of those mandrels above, but the housing, counter, and gears are all in great shape. I'll have to see how it goes trying to pull the bearings and find replacements.