TUS172 wrote:
We are talking about a custom job done by craftsmen that obviously have a passion for doing things right, I personally
am one who is willing to have faith in their decisions as to what is best.
...
I have sent a portafilter to Lino that fit both a '86 and a '67 Cremina perfectly... I don't think that Olympia (small shop) has been in the habit of changing dimensions or design of something that works well.
...
From a tolerance point of view I also don't think that the Portafilter to grouphead fit or ear to rim distances, are measured down to ten thousandths of an inch

Not questioning the skill of these two professionals, or that they wouldn't do things right, but they should be provided with enough data for them to know what is right. One portafilter to measure and some assumptions about Oly practices over the decades are not a very broad data set.

I believe if the naked portafilter is manufactured to the tolerances of the older portafilters we will be okay, if my 1976 portafilter is representative.

With the tongue of my calipers, it is difficult for me to get a precise measurement of the rim support wall relief, because there is a radius where the wall meets the ledge.

Regards
Timo

Vis variations in the portfilter size:

Please nobody bite my head off but, I got really lucky a while back and landed myself a few OE portafilters in varying conditions and what appears to be varying ages - I can confirm that there are minor differences in these eg length and thickness of the lugs. Now my 70's Cremina grouphead was possibly dremelled to allow a non standard portafilter to fit so I also tested all these out on the 80's Maximatic and the 60's (we think) Club and I can say that that they all work with slightly varying degrees of rotation for the lock in. This group includes a modern version and what I assume is a 60's head from the club.

I dont have callipers to measure these but I'll try and post a picture for a visual cue tomorrow.

Hope that helps,
sneaky

Bite , your head off- it is the furthest thing from my mind...

I want to invite you over to dinner ,have some great wine, followed by Port, Scotch and cigars( and bring those PF with you!) . When you are sleeping, the elves will wisk them away and you have no remembrance of the night before--

Invite is in the mail

mogogear wrote:Bite , your head off- it is the furthest thing from my mind...

I want to invite you over to dinner ,have some great wine, followed by Port, Scotch and cigars( and bring those PF with you!) . When you are sleeping, the elves will wisk them away and you have no remembrance of the night before--

Invite is in the mail

Amen Brother...Amen
richard
PS, are they to be for sale to the highest bidder / brudder?

Lino has gotten the measurements off my portafilter and wanted to know how many would be interested in the stainless version as compared to the brass. I am partial to stainless... but am willing to go with the majority rule vote.

My entry is 2 in stainless. Others?

I'll go with either.

I could go for either, as well.

Regards.

I'm in for one of whatever majority rules on.
paul

Since my PF is close to being roughed out, I shall opt out.
Lino, I use a truckers', stainless steel, bumper buffing compound for most materials, it also works well for brass, it just cuts faster. 'Wrights Copper Polish" or a red or white rouge buff from there. If I may help in any way, let me know.
sincerely
richard

Hey Guys,

Sorry about my long absences between posts...

Regarding the material, I'm partial to brass, solely because it will be much easier for me to cut. (and therefore cheaper).
Brass appears to be a bit more expensive, but I haven't looked around much. Shorter machining time may offset that anyway.


Pricewise, it's too early to know. I did say it'd be more than $100, and I'll stand by that
But keep in mind $400 fits that spec, as does $1000. I never said I could do it for $120.


Here's my general plan:
I'm gonna make one first for Bob. If it fits both his machines, I'm willing to call it good.
At that point, I'll set a price for additional PFs and someone can coordinate a group buy if there is interest.

Also, I may not have mentioned it here yet, so I will now. I'm not a professional machinist, that is, the little machining that I do is not paying the mortgage. And that's how I like it. However, when one of the jobs comes along that does pay the mortgage, guess what has to slip...
So, don't plan on any of this stuff happening quickly...


Hey Richard,
I do have a buffing wheel setup, and I need to experiment with more compounds. With these, however, I was hoping to banish them to vibratory polisher... It works wonders to stainless, and recently I've had good luck with aluminum, so I'm optimistic that it will do well with brass also. Clearly I'll try it on a scrap first...


ciao

lino

Hi Lino,

Pricewise, it's too early to know. I did say it'd be more than $100, and I'll stand by that Wink
But keep in mind $400 fits that spec, as does $1000. I never said I could do it for $120.

That would be the way I said I'd look at it also! $120 was a ball park estimate to inject a bit of reality into the "gee whiz"

Here's my general plan:
I'm gonna make one first for Bob. If it fits both his machines, I'm willing to call it good.
At that point, I'll set a price for additional PFs and someone can coordinate a group buy if there is interest.

You'll have the time invested in the tooling mods, process planning, and trial and error and so you should be the one to do the job. That way you may be able to get a part of your investment back.
My small shop with odd equipment requires that I make almost every bit of tooling from scratch and of old odds and sods so progress tends to be a bit slow.

I like the 3d rendering of the real PF, when you pull that one off, I believe it will be way better than my "naked" as a replacement! The grip stop on the handle shank really adds class! Plating would be something for you to work out, I would let the individuals do it if only a couple wanted it.

Polishing is an art form, The tumbling barrels and vibrators I've seen used. Media sensitive but they can do amazing things. One shop used uncooked rice and stannous oxide for a final mirror finish on individual special "one off" plumbing fixtures.
Let me know if I may be of service!
richard
Enjoy the journey

Don't forget the chamfer (slightly exaggerated in the drawing below) around the basket-rim support-wall A wall too thick causes the baskets to sit too high.



Regards
Timo

Hello to everyone, just picked up on this thread and saw the first few entries That mentioned me and my portafilter casting experience. I cast one that was missing from my Europiccola. I actually sculpted the portafilter in wax and made sure the wax fit into the grouphead before casting. And even though it fit there was alot of finishing to do after the cast to make the fit work.



So it is not something I could do economically or without the machine to do a fitting. I think a machined piece would make more sense to keep the proper dimensions.

As well, I finally cast a few La Peppina portafilters, however they did not come out as expected and will now become portafilter art and I will post pictures soon. I will be casting again in September and perhaps give it another try.

If Brass is the preferred then that choice is fine with me. Will these be sent out by the individual owners for plating?

TUS172 wrote:Okay... I am in for at least one.
Fullsack is in for at least one.
Any other takers out there?

i am in for one

Okay... by my count that makes 7 so far ... any others with interest?

I am on stand-by. When Lino has made one, he will know better what the cost per PF will be.

Plating is typically done on a minimum order basis. The ante is typically around $100. Chrome-plate one PF or chrome-plate ten of them, and the plating costs for the batch are the same.

Regards
Timo

Thanks Timo... You know an option would be to send this first prototype to more than one Cremina owner(who is interested in buying).... That way we could get a consensus as to fit. I own a '67 and a '86. If we could get perhaps a couple from the '70s and perhaps even the '90s I think we could put to rest any reservations about fit. I could try it out and if it fits to my satisfaction, send it on to someone and that person could send it to another invested party before Lino produces any others. The purpose is to get the dates of manufacture covered. If it works on that kind of spread than I think we are pretty well covered. Lino has stated that this could be a process that takes a while so we should take the time to see that he does not waste his time by producing 7 - 10 of these and then have 4 or 5 come back. I have a feeling that this first prototype will work for all if it works in my 2 Creminas... but why not make sure?
Thoughts?