One of the companies I contacted regarding making naked PF for the Caravel got back to me. He asked if aluminum could be used instead of stainless. Considering the coffee will not make contact with the PF or minimal contact. The coffee will flow from the basket directly to the cup.
Any thoughts ? He noted the cost of Al is 3x less than SS. Also considering getting proper fitting tampers made to match.

I wouldn't, with the stainless group I imagine the aluminum portafilter fins would take a beating.

As a question of hardness and deformability, there are some aluminiums that I suspect out perform some steels... but will they be 3x cheaper?

Hardness table https://www.tedpella.com/company_html/hardness.htm

My Zaconni PF is made of Brass and has lasted over 30 years without issue. It's made of brass which has a hardness # of 3-4. Aluminum hardness # is 2-2.9 while steel is 5-8.5.
I suspect the cost factor is based on cost to machine not just cost of material.

Types of Aluminum http://www.emachineshop.com/machine-sho ... ge486.html

Thanks for the links - perhaps an engineering type can help clear the topic up.
Looks like it's difficult to find direct comparisons of the alloys or heat treatments, but there seems to be a claim that some surface treatments on aluminium may help http://www.moldmakingtechnology.com/art ... rsus-steel
Perhaps a combo of alloy, heat and surface treatments may bring an aluminium part within usable spec for a portafilter but steel is probably the simpler solution...

Also, after making sure the thermostat was kept in the on position (a gently inserted chopstick is ugly but functional) the Willhi temperature controller works great with a little tuning of the PID. I can't complain about the price and there is no permanent modification to the Caravel!

Edit: swapped in a little silicone wedge that doesn't get loose like the chopstick did!

Put this on back burner while entertaining guest from Australia. Back to the grind now.

Managed to have a drawing made of a bottomless PF for the VAM \ Caravel

Here is format in jpg form. I've asked for a quote on brass version vs aluminum version in keeping with feedback regarding part robustness.



I added .5mm to the angle of the PF clip in order to increase PF pressure against PF group seal. I've always felt PF should be tighter when locked to PF seal

Third 's a charm. Testing O.E. kit on newly acquired Caravel primo 1.0. Yellow intrigued me. Just sold a very nice 1.3. Decided to dissassemble machine and soak parts for 24hrs in O2 and detergent bath, mild scrub and rinse. Already seen here with assembled piston and new micro "O" ring installed. Have tried Francesco gaskets both rubber and silicone on prior machines.

My experience with aftermarket replacement VAM \ Caravel seals

I'm on my fourth VAM/Caravel ranging from piston type 1.1,1.2b/c and 1.3.
I've replaced the seals on all of them, trialling seals from three different supplies.
Francesco x2, Brooks and O.E.. Trialled both Francesco seals regular and silicone.
Both are great with a slight preference to the silicone variety. Brooks only sells silicone variety which are also good but shipping is double (Holland) compared to Francesco (Italy).
O.E. sells are of the regular variety and claim to be universal in the kit.

I received the kit which included a PF gasket, two main piston seals and a few varying sized ring seals.
The main seals were very loose and soft compared to other competitive seals and required some of the other ring seals to keep them stabilized on the piston. They ended up being either to loose or to tight in the housing during a pull. I emailed O.E. Twice and received a reply only after PayPal got involved, stating that there are to many piston variables for all seals to fit although selling page only stats universal. I tried the seals on three different machines with the same results. After about 1 month of usage I noticed a pop sound on the lever lift and decided to investigate by removing the piston. One of the seals had deteriorated and a piece ripped off. I've included a two pictures below. The seals cost me $40 cda. lost money and hassle. This incident and how it was handled would stop me from any future dealing with Orphan Espresso.
For those looking for VAM \ Caravel seals I would suggest Francesco's seals based on quality, fit price and customer service as the best buy.


N.B. I used lube on all my installs and was careful not to bend or cut any seals while placing back in piston or piston housing.

I've had the same set of OE seals on my 1.0 since 2012 and they are still going strong. It's one of my daily drivers so they have hundreds of shots on them. Bummer that your set didn't work out.

It seems that the seal material used has been changed to a thinner less wearing material.
As much as I'm displeased on the failure of the seals I'm more displeased on how my issue was handled. No reply after 2 direct emails waiting at least 1 week between messaging. Only reply after going through PalPal.
PayPal suggested tracking return of seals back to vendor before compensation but I regretfully decided to continue to test them hoping the seals would seat with usage. They got worse and the thin material softened to the point of ripping as seen on previous post. Side by side thinner and softer to other seals I used from competitors or the OEM seals that came with the machines.