PFM Blind Cap Frustrations

[RayCornett]

So, I have a PFM I grey. I want to replace the sac and oring. However, the blind cap is the most stubborn blind cap I have ever experienced. I've used heat, soaked it like crazy........nothing I do looses than screw inside and along the way the cap has developed cracks along three sides.
If I knew I could find a replacement I might just cut bait and break the blind cap OFF to end the frustration.

Anyone have any advice?

[D Armstrong]

PFM blind caps can be a problem this way, shrinking on to the piston tube. The cracks were likely started already from the extra stress. To add to things, the cracked blind cap can affect the vacuum seal needed to fill the pen, so they will have to be properly repaired when you are done. And, of course, you are not likely to find any spare grey parts, as it is the scarcest PFM color, and so get hoarded.

Heat is good. Soaking is good. Patience is better.

Use an ultrasonic if you have one, as it can get soapy water into the spaces better than plain soaking. I have never found that an ultrasonic bath has made cracked plastic worse. (But I'm sure a nice, broad statement like that will bring out all the helpful folks who haven't yet answered constructively.)

Also, heat the piston tube, rather than the blind cap. The heat will transfer quickly up the tube into the socket, where it is needed, rather than having to warm the entire blind cap just to get the socket expanded and softened. Go slowly, as Sheaffer's plastic is quite heat sensitive, as well as brittle. If the tube gets too hot to put comfortably against your lip, it's too hot.

Hope this helps.

[RayCornett]

I do have an ultrasonic. I've been doing all of the above. I am sure it will eventually give. I can also fix the cracks with no problem. It's just very frustrating. In all the repairs and restorations I have ever done I have never had this much trouble with a blind cap.

[D Armstrong]

Heh. That's because it's a grey.

Be sure you relieve the socket before you put it back together, or it will try to crack again. Doesn't need to be much, just a few thousandths.

[Chrissy]

Did you ever manage to remove the blind cap? If you did then I would recommend that Captain Tolley's Creeping Crack Cure will probably work really well in sealing the cracks without making them look worse than they look already. If you need a stronger adhesive to hold them together then please let me know.

[RayCornett]

As of about 3 days ago the blindcap finally freed itself. Turns out the rust on the screw was only part of the problem. Someone mentioned pure alcohol down inside the metal tube and letting the barrel sit upright for a while. This did the trick. Once I was able to get more rust out of the way I noticed that a big part of the problem was that whoever had decide to mess with the pen in the past had put the screw back in very crooked. I have already begun work on the cracks.

[RayCornett]

Heh. That's because it's a grey.

Be sure you relieve the socket before you put it back together, or it will try to crack again. Doesn't need to be much, just a few thousandths.

First off, I have been a fan of your site for about 2 years now I believe...but what do you mean relieve the socket?