# Making a pressure test gauge using a single basket.



## marcuswar (Aug 19, 2013)

Months ago I bought a pressure gauge and convertor to attach it to me Gaggia Classic portafilter. It was nerve wrecking cracking the double spout off my portafilter but it worked well for me and I set the OPV to 10bar static as recommended by other members. Having set the OPV I put the gauge away in my 'coffee cupboard' and forgot about it.

Fast forward a few months and a friend asked to borrow it to set his OPV. We connected it to his machine and noticed a leak from the thread, so I tightened the nut but the leak got worse! Looking at the converter it looks like the tightening of the nut has split the converter!









Rather than simply buy another cheap converter it occurred to me that a gauge attached to a blanking plate would be far more flexible as it could be used in any machine using a standard 58mm portafilter without having to remove the spout.









It then occurred to me that rather than buy a blank flushing I could try using one of the stack of single baskets I have and never use.









Building the gauge consisted of cutting a disc of metal from a beer can and gluing it in place inside the basket with epoxy glue.









I also added some of the remaining epoxy glue on the underside of the basket just to make sure all the holes are filled.









...continued in next post.


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## marcuswar (Aug 19, 2013)

I left the epoxy to cure overnight and then drilled a 10mm hole in centre of the disc.









The gauge was then attached with some PTFE tape, a dowty washer on either side of the basket and the 1/8th BSP nut.









After putting together a quick test for leaks and success !









*Advantages ;*

Can be used on any machine that uses a standard bottomless basket.

Doesn't require the spout removing from the portafilter in order to use it, just click and go.

The gauge can be rotated to any position for easy visual access.

*Disadvantages ;*

Requires a bottomless portafilter.

The epoxy I used is only rated up to 93 degrees so the gauge should only be used on a cold machine.


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## marcuswar (Aug 19, 2013)

*List of parts ;*

*
*1 x 40mm Pressure Gauge, 14-20bar max reading

2 x Dowty washers 1/8th BSP : http://www.ebay.co.uk/itm/331217138335?_trksid=p2059210.m2749.l2649&var=540405498661&ssPageName=STRK%3AMEBIDX%3AIT

1 x 1/8th BSP nuts : http://www.ebay.co.uk/itm/131193891377?_trksid=p2059210.m2749.l2649&var=430433182623&ssPageName=STRK%3AMEBIDX%3AIT

1 x single basket

1 x epoxy glue

1 x tin of beer ... to drink, and then cut up the tin to use









...the last 3 items (and a chunk of time) can be replaced with

1 x 58mm blanking basket : http://www.ebay.co.uk/itm/321367609222?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649


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## Dylan (Dec 5, 2011)

Few month bump on this as I missed it when it was posted but wanted to say that this is a great idea, and should be commercialised!

Edit: How hot does other epoxy go? I know you can get "gasket maker" sealent that is rated up to very high temps.


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## marcuswar (Aug 19, 2013)

Thanks Dylan

I just used what I had to hand at the time. If I did it again I'd probably just buy and use a cheap blanking basket as it would probably be cheaper than buying descent epoxy and there would be no danger of the epoxy failing.


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## Dylan (Dec 5, 2011)

That s very kind of you Marc, thanks. Normally I would be very much up for making one, but I'm really busy at the moment and have other projects on the go!

I'll shoot you a PM with my address.


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## urbanbumpkin (Jan 30, 2013)

Great idea I was thinking of trying this.

I was just scouring ebay for the nuts. Any recommended suppliers? The ones I've found are a couple of quid for 1 nut.


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## marcuswar (Aug 19, 2013)

Thanks, as you say I had to buy the nuts in multiples of two so I have a spare, and the dowty washers came in a pack of 10 I think.

The nuts where b ought from "Cotswold engineering supplies - 01684 298786" through eBay and their product code is "828/1" and are described as "LOCKNUT 1/8INBSP"

I'll drop you the nut and a couple of washers in the post on Monday


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## urbanbumpkin (Jan 30, 2013)

Thanks fantastic Marcus, and thanks for getting back to me. Let me know what I owe you for postage and I'll make a donation to the forum too. Do you still have my address?


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## marcuswar (Aug 19, 2013)

Happy to help. Don't worry about the costs it'll only be pence, just add it on to any forum donation you make









I'm sure I should still have your address in my inbox, if not I'll pm you.

Are you thinking of re-purposing a single basket or will you be using a blind basket ?


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## marcuswar (Aug 19, 2013)

The nut and washers are in the post to your home address Urban.


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## urbanbumpkin (Jan 30, 2013)

I've done the above mod thanks to the parts sent by Marcus.

I used a blind basket, However I couldn't work out why it wasn't locking in till I twigged that the end of the gauge was knocking into the shower screen.

I managed to lower this by slackening off the nut and packed the other side with a washer. Seemed work fine. It might be the case that the blind basket is slightly shallower or that my shower screen on my Andreja is lower.


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## marcuswar (Aug 19, 2013)

Well done Urban, thanks for posting. I hope it encourages others to do this as it's a great little device and so much more versatile than having to remove the spout off a portafilter every time you want to test a machines pressure.

Having looked at my blind basket and compared it to a single I can see the single basket is actually slightly deeper so I think this is why I didn't have this issue.


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