Looking for 5 people for group purchese of replacement PC Engine CD middle gears!

Yeah, there are little bubbles. You think he made a cast from a good middle gear? Do those even exist?

 

Since he is from Japan, I would think it's easy for him to track down a good middle gear to cast from. Ideally it makes more sense to cast an original pristine part. But I suppose if it's necessary, a replica of a replica is better than none.

 

I could pick up a replica, but a broken gear would do fine as long as it can be accurately measured with a micrometer (height, diameter, shaft bore etc.)

Mine won't be cast, they'd be properly manufactured.

I should really get myself a PC Engine and CD-ROM... then I could just measure the (hopefully) good one!

 

Use a small digital vernier caliper. I was reading the Machinery's Handbook to brush up on the gear lingo. I'm interested in generating a proper mechanical drawing for this gear but I don't have the CD-Rom to make the measurement. It's not enough to measure middle gear by itself. Some reference measurements need to made on the pinion gear on the motor, its shaft and the middle gear's too.

 

Here's a photo of the other gear I have:


Do you think it would still be useful?
Properly manufactured gears sound awesome! I don't like your chances of getting a good middle gear if you brought a CD-ROM2 of your own, I've heard they all have this problem.

 

Yes, I think you should save it. It can be handy in making measurement of the width of the tooth and perhaps the the root diameter since most caliper may not reach between the teeth of a complete intact gear. Do you have scanner to scan both side of the gear? If you do, scan it with a good steel rule if you got one.



As you can see from the diagram, there are many critical dimensions needed to create a proper gear. The pressure angle and the pitch diameter are critical to ensure proper mesh and smooth operation. I know the gear is small and some of these things might seem inconsequential but to do it right you got to do the due diligence.

 

A scanner? Like, the thing for a PC that you can make copies of papers with?

 

Yes, sometime flatbed scanner is useful for scanning a flat profile at 1:1 scale. Using a photo camera can distort perspective. The JPEG can be imported into a CAD program as an underlay for tracing. When you include a steel rule in the scan, it helps on scaling the JPEG within the program if necessary.

 

Oh, cool! I think I'll just send it to retro (if he thinks it's useful) though, he sounds like he knows what he's doing

 

Exactly what I do

As long as the gear will go together (reasonably) as it would have been (as in there's nothing missing on the inside), then it shouldn't matter if a few teeth are missing - that would indeed suffice, then.

 

Yeah, as long as the outer diameters, thickness, the number of teeth on each side are known, you really just need one good tooth from each to do circular patterning on CAD.

 

It's what you see in the photo basically If you think it'll be useful, send me your address!

Out of curiosity, how do you make these things anyway?

 

Injection moulding and/or waterjet cutting, same way the originals were made.

 

Ooooh! That's cool! Do you know someone with some fancy equipment or something?

 

A factory full of fancy equipment

 

Do you own the factory? Are you an old timey Victorian factory owner who's workforce consists of orphans?

 

Boy for sale!

Haha, no.

 

I would be up for a stock of 10 or 20 of these gears.

 

Not a problem. I'll have more of an idea of what the price might be when I've got a broken one and can ascertain the potential demand.

Incidentally, does anyone know what models were affected? Are the American ones equally as bad? And was it just the CD-ROM2?

 

all made in the same factory.
just like shoes top make and low made are made the same a factory work told me a few years ago even down with food aswell.