A little math problem.

[Whitetrashrocker]

I made an idler wheel to replace the dry hard rubber one in my record player. I found a place online that will re-rubber your old one, but I'm not gonna cough up the $70 for it.

The OEM has a diameter of 2.0"
My dried one had a diameter of 1.990
The one I made was a little smaller at 1.980

The drive spindle drives the idler wheel and the wheel drives the platter.

If the drive spindle is constant, will the change in the idler wheel diameter, change the over all speed of the platter?

 

[itsid]

the idler does NOT change the speed, it doesn't matter what diameter it is.
it's not involved in any gear reduction as long as there's no belt involved.

friction rollers (like that supposed to be) always have a fixed speed at their outer circumference (dictated by the driver pin) and it's only said circumference speed that dictates the speed of the platter of course.

Looks nice btw..
but open up the bore and add an oilite bushing (or better find a fitting ball bearing)
it'll run MUCH smoother when properly rotating on the shaft without grabbing it

'sid

 

[TT540]

I vote no. The idler wheel is just a cog between the two. Something to connect the platter to the driver. The RPM of that idler wheel will go up a tad, but the transfer of motion is still one to one.


But now if a go kart is on a tread mill... That would be tricky.

 

[Nosandwich]

Well, I was going to hep with this math problem, but I couldn't get my shoes off, so I couldn't count high enough.

 

[Whitetrashrocker]

Thanks Sid, that's kinda what I was thinking but I started over thinking the ratios.

I'll keep an eye on it to see if it needs a bushing. I put a little grease on the spindle. It works better than it has in 40 years.

And nosandwich, as long as you don't have to count to 21 we're good. I can deal with 20 but no more.

 

[Nosandwich]

I can go as high as 23. Happy nightmares.

 

[TT540]

< can count to 21.

Wait for it..... wait.... it'll come to you next trip to the bathroom

 

[Nosandwich]

+2 If you count round numbers.....

 

[itsid]

I can go as high as 23. Happy nightmares.

if you can't at the register in your local supermarket .. it doesn't count.
'sid

 

[bob58o]

if you can't at the register in your local supermarket .. it doesn't count.
'sid

He's been banned from the local market.
Now he needs a disguise for shopping.

 

[Nosandwich]

I use my fake Robert D. Jung credit card, no counting involved.

 

[TT540]

I don't know why this occurred to me, but subtraction really throws a kink in things.

 

[Nosandwich]

I thought you changed your mind on that operation.