Vacumatic repairs

[antonio ilmonaco]

Hi,

 

I had a 1948 P51 vacumatic demi sitting in the drawer for some time. The diaphragm had ossified and the previous owner, trying to actuate the filling mechanism, had also cracked the pellet pocket beyond repair. I decided to bring it back to operating condion.

 

I start with some polyurethane rod, i drill a 2.2mm hole in the center, then a 2.5mm hole but not all the way in, beacause the front opening is larger than the rear one

 

 

Then i chamfer the rod, using 22° cone half-angle

 

 

I cut the outer diameter to 5.5mm

 

 

Then i make a groove to 4.5mm outer diameter

 

 

I then cut a recess in the inner part of the hole using a self-profiled chambering tool

 

 

After parting the useful part of the rod I get a nice pellet pocket

 

 

Here's the complete filler unit ready for assembly

 

 

I have glued the new pocket to the filler rod

 

 

I make myself a pellet installer from a length of steel rod

 

 

Then the new diaphragm gets a talcum powder bath

 

 

The filling unit gets then re-assembled, and the new diaphragm cut to length

 

 

The filling unit is reinserted in the barrel using a vacumatic tool (for making yourself such a tool have a look at this post : https://www.fountainpennetwork.com/forum/in...st&p=761958

 

 

The barrel is ready for assembly now

 

 

And here's another vacumatic P51 ready for another 60 years of work!

 

 

All the best,

Antonio

 

 

 

[david i]

an impressive procedure

 

-d

[SMG]

Well done on the new pellet pocket. Great job turning that out. Will have to make some of those up to resurrect the busted up fillers I have laying about. I actually like your method better than the old one of making them from a papermate pen refill.

 

Cheers,

Sean

[burmeseboyz]

I think this qualifies as Vac-p0rn. Nice pictorial! I just use a snipped q-tip as a pellet pusher. :-) You're making me want to get a micro-lathe and play with it.

[Buzz J]

Very nice bit of craftmanship!

 

Now if you'll just repeat about a thousand times, send 'em over to me and in about 15 minutes, I'll sell them all at the Ohio show!

[Firefyter-Emt]

I have a question, two really... Now forgive me, because this is one repair I have been too chicken to try yet.

 

First, do you need to "crimp & roll" the end of that to hold the pellet, or is the pellet and sac enough to retain it in place? Next... I hear a lot about using a dremel tool to remove the old pellet. Are you guys grinding out the old pellet and replacing them? I don't recall seeing new pellets, what are you using to replace the pellet?

 

Nice lathe work, it is so nice to have the tooling to just up and say, "Well, I guess I will just make a new one!" My kind of thinking, I love it!

[SMG]

My assumption would be that the pellet would stay in the replacement by friction alone, but a rolled edge would help retention.

 

 

As for replacement pellets, they come installed in the new diaphragms. Using a Dremel one simply melts the old pellet onto the burr of the Dremel and then it can be easily pulled out. If the pellet does not melt to the burr, then you need to destroy enough of it that it will collapse when you fish it out with a dental pick. That way it will not crack the pellet pocket when you remove it.

 

Of course the above works great, except when some SOB has used a BB from a shotgun shell as a new pellet.

 

Cheers,

Sean

[Aslan]

Wow, very impressive! Thanks for the pics.

[sph33r]

Nicely done!

[antonio ilmonaco]

Hi,

 

Thanks for your comments!

 

First, do you need to "crimp & roll" the end of that to hold the pellet, or is the pellet and sac enough to retain it in place?

My assumption would be that the pellet would stay in the replacement by friction alone, but a rolled edge would help retention

 

There is indeed a recess in the pocket, the diameter is increased from 2.5mm to 3.0mm in the inner chamber for the diaphragm to expand around the pellet.

So this isn't a friction fit and trust me you need a fair amount of pulling to extract the diaphragm from its pocket!

Here's a close-up op the tool used to cut the inner groove in the pocket :

 

Next... I hear a lot about using a dremel tool to remove the old pellet. Are you guys grinding out the old pellet and replacing them? I don't recall seeing new pellets, what are you using to replace the pellet?

Of course the above works great, except when some SOB has used a BB from a shotgun shell as a new pellet

Well, this pocket was dead anyway so i cut the old pocket in halves and retrieved the pellet. An alternative to the dremel deburring tool is a special extra fine copper tip fitted to a soldering iron. With some caution not to damage the pocket you can melt old pellets, including"lead shot" pellets.

 

Now if you'll just repeat about a thousand times, send 'em over to me and in about 15 minutes, I'll sell them all at the Ohio show!

 

Well, just to make things clear i'm not interested in making/supplying pen parts or repairing other people's pens. Many professional repairers have skill and experience and earn their living bringing pens back to life, and i already have too little free time for fixing even my own stuff. From time to time i repair pens or other items for friends, but it always for free.

Besides, mass production in my little workshop would make no sense at all : let's say i need 20 minutes to make a properly adjusted pellet pocket and sell it for three bucks, no need to do the math, i'm not even close to earning anything!

 

I'd rather you all to try it for yourself and post nice pictures of your work!

 

All the best,

Antonio

Edited October 20, 2008 by antonio ilmonaco

[SMG]

Sorry, didn't catch the boring step. Yes that would make for a retention lip in the pocket.

 

Personally I use the dremel for 100% of the pellets unless they pop out on their own as some will. These though are usually on the metal fillers, the ones with plastic cups I always melt them out with a dremel.

 

I have found that method works best for me, though not to say it is the only method. Some are better than others, I hate to hear of people using heated pins and prying the pellet out of a cup. That is almost always a way to damage the pellet cup. I have seen too many of them which were done by prying wreck the pellet cup to even consider it anymore.

 

Will have to get some material and see if I can turn up a few cups myself. I probably have about 5 fillers that need new cups on them.

 

Cheers, and thanks.

Sean

[PenFisher]

A great pictorial! If a picture is worth a thousand words...you just wrote a masterpiece.

 

Thanks for this post...

[philm]

Well done Antonio. And a very nice photo essay.

 

Thanks.

 

Phil

[antonio ilmonaco]

Hi,

 

Thanks for the comments, please don't hesitate to add pics of you own homemade pellet cups!

 

All the best,

Antonio

[fibreglass_works]

I have been wanting to ask, How to get the black pellet out of the filler rod????? :embarrassed_smile:

[antonio ilmonaco]

Hi,

 

The pellet pocket is just shellacked at the end of the plunger rod, be careful when dismantling the filler unit at 60+ year old plastic is always likely to snap under too much pressure.

 

All the best,

Antonio