The PHILCO Phorum

How does one go about removing the dial drive assembly on a 650?
I'd like to clean and re lube the assembly as it's dry and ruff.
I see this guide at http://www.philcorepairbench.com/tips/svctip14.htm
I can't get the assembly past the semi circular wire it drives. I sure do not want to break any thing.
thanks

Hi Bill

I think Brian (BDM), our resident Model 650 guru, has removed, lubricated and reinstalled these in the past.

Brian, any words of wisdom you wish to share?

I tried to remove one of these dial drive assemblies once, many years ago, from a 116B chassis. It did not want to come apart, and it never did work correctly afterwards. I have not tried to disassemble one since.

First, remove the two screws holding the shadow meter bracket


Then, remove the dial scale mount. It has an inset screw on the backside


Then, remove the screw behind the dial scale mount


Last, remove the two upper dial turnstile bracket screws


Ed(etech) has also done this. When I removed mine last year. I didn't take it apart. I just soaked it, blew it clean and re-oiled it. Works perfect to date. If I remember correctly, the dual speed dial assembly has a clip on the rear retaining the clutch pressure spring(for lack of a better word). Ed may be able to comment further. Proper adjustment is needed when re-installing it. Or it will bind, or have a gravel feel to it. Now, your chassis looks exceptionally clean. Maybe you can just leave it as is, blow it clean and apply a dab of oil. That's what I did with my 650B. It's as clean as yours.

I did exactly what Brian described. Once I had the drive assembly removed, I removed the clip and removed the shaft and bearings as per this procedure. http://www.philcorepairbench.com/tips/svctip14.htm

Clean the shaft and bearings and re-lube with grease. I used wheel bearing grease, because that is what I had available. It worked fine. I did not have any slipage in my unit, so I did not have to retension the spring. I just re-assembled everything. The only thing I found a little bit tricky was adjusting the dial drive engagement to the semi-circular ring. The two screws holding the dial scale mount have elongated slots allowing adjustment of the drive ring to the semi-circular ring. You might have to try of few adjustments, but you will get it to run smoothly. When I had finished the job, I was glad that I did it. My 650B tuning drive runs very smoothly and has no slipage. I hope this helps.

Ed

Thanks guys and Brian that is a great guide. One thing that gave me trouble was trying to reinstall the dial drive assembly. The two aluminum sleeves that ride on either side of the hoop are spring loaded and must be held apart to allow the dial drive to be installed without possible damage to the hoop or drive assembly. I did this by prying the two sleeves apart with my fingernail then placing a small plastic shim between the two sleeves. Once installed I removed the shim.

Now the bad news, it's still rough. I did not stretch the spring. The roughness is in the dial drive assembly not the drive system. When I had the drive assembly apart I cleaned it completely. I used grease made to lube screw drive garage door openers. The balls do not seem to be flat spotted. The outer bearing race looks fine also. Looking at the inner race AKA vernier shaft it was slightly rough looking where the balls ride. I used some very fine sand paper to polish this area. I folded the sand paper over the inner race the twisted the shaft. Once done the race looked much better.

If not enough spring tension can cause the vernier shaft to slip will too much tension cause roughness? If so how can I lessen the tension without the possibility of damaging the spring?

Bill, let me play with the one off my parts set. BTW, the one in my 650X is slightly rough. Not much, but I believe it's the shaft itself. I'll get back to you on this.

Bill, yes too much tension will cause roughness as you say. It's pulling up on the shaft. Try loosening it and re-adjusting for slightly less tension. I was playing with my parts set, and I can get it pretty smooth without slippage. Make sure there is NO grease on the tuner turn-stile wire(lack of a better word). It's a little tedious, but just keep doing it ever so slightly.

BDM Wrote:Bill, yes too much tension will cause roughness as you say. It's pulling up on the shaft. Try loosening it and re-adjusting for slightly less tension. I was playing with my parts set, and I can get it pretty smooth without slippage. Make sure there is NO grease on the tuner turn-stile wire(lack of a better word). It's a little tedious, but just keep doing it ever so slightly.

The roughness in mine is not related to dial drive to drive wire alignment.
I could feel the roughness with the dial drive in my hand. With it installed the roughness is felt mostly in the outer high speed knob. The roughness goes away when pressing in on the low speed knob while turning the high speed knob.

Note I found the dial drive to drive wire adjustment in its loosest position and its in the full loose position now with no slippage. The spring tension adjustment I was referring to is the spring that loads the balls.

Well, then the bearing race or bearings have an uneveness in them. I really have no further suggestions without taking one apart and trying a few tricks. May not be able to repair it depending.

That's what I figured, thanks.