Pinner Machine Shop Releases Aluminum Brake Bleed Cups

Jan 16, 2023 at 12:26
by Matt Beer  
photo

Pinner Machine Shop is a small-batch operation setup in Whistler, B.C. with a knack for solving mechanic's problems but can also prototype whatever part your 3D printer can't handle. Lately they've been diving into the world of tool upgrades, in addition to their Boost hub adaptors and axles.

Recently, their CNC'd brake bleed cups have been popping up on Pinner Machine Shop's Instagram account. They feature a brass plug and fitting, complete with seals, that adapt the funnel from Shimano's lever threads to also work with SRAM, Magura and Formula brakes for a clean gravity-style bleed or to simply purge air from the master cylinder.



They've also been producing high-tolerance 28 and 32mm sockets to firmly fit the low hex heads of some fork top caps. You can find out more about Pinner Machine shop and order through their online store here.

Author Info:
mattbeer avatar

Member since Mar 16, 2001
328 articles
Must Read This Week
Greg Minnaar Off Santa Cruz & Reportedly on Norco for 2024
97326 views
ARC8's Prototype Downhill Bike Uses a Sliding Shock Mount
45975 views
Review: Atherton 130.X - The Lugged Carbon Cruiser
45383 views
Pinkbike Poll: What's Your Ideal Two Bike Quiver?
43090 views
Check Out: Waterproof Shoes, A Clever Hip Pack, Wireless Dropper Post, & More
37318 views
Tech Briefing: November 2023
35791 views
CeramicSpeed Announces $669 OSPW X Upgrade for SRAM Transmission Derailleurs
32776 views
Intend Release Limited Edition 'Moto' Fork & Shock Set
30884 views

112 Comments
  • 142 2
 I thought the reason for bleed cups being plastic is so you cant strip the threads in your brake lever bleed hole? Suppose the mechanic who has everything would NEVER do that...
  • 106 1
 It is - but now you have the option to f*ck shit up ¯\_(ツ)_/¯
  • 67 0
 Yup. Not only that, but you can see the level on the side not just from above.
  • 30 1
 This for the people who throw the manual in the garbage.
  • 30 0
 You won't strip the bleed cup with this model, so if you value bleed cups over brake levers, you're set...
  • 4 1
 @Nygaard: I was glazing over comments and thought you told the guy to STFU and was like wow ok so we feel hostile today. Took me a second read to see what you were saying lol.
  • 18 18
 SRAM and Hayes both use metal bleed fittings on the syringes and all (except Magura) use metal screws tightened with a wrench to close the bleed port. A finger tight bleed cup (tight enough to deal with the oring, not the tread) won't strip anything. Also, a Shimano cup wears out after about a year of heavy use so in 5 years ish you'll break even on cost.
  • 4 0
 This is for the mechanic who likes to live dangerously.
  • 3 0
 @konadan: quickly followed by the brake lever.
  • 15 0
 @samskuatch: they're 5€ over here so it's about 16 years
  • 15 2
 HOPE Technology have had metal brake cups for a while now, they work perfectly on Shimano levers, with their own top cap adaptors and unless you're cackhanded, you wont strip your lever threads.

The amount of fluid it holds will easily cover the gravity bleed without looking at the level. Any fluid remaining you just put back into the container. I have used and thrown away many plastic bleed cups, wasteful IMO. Also costs £25 for the Hope one and it comes with some DOT fluid. The Shimano plastic ones a few £ each at a time and last a few months.
  • 6 5
 But then you put a metal plug in the hole. No, they're plastic because for most people bleeding 1 set of brakes once every year or two, it will never wear out and has zero benefit being metal. However, I've worn 2 shimano cups out, now on magura brakes, but if this had been available when I bought my first shimano, I could have adapted it to the magura instead of having to buy a new bleed kit.
  • 6 3
 @samskuatch: Yeah and for shimano you must heavy use your bleeding kit if you want decent braking feel.
  • 2 0
 @mrift04: DOT fluid is hygroscopic, and I don't like potentially contaminating my bottle over and over.
  • 3 2
 @nickfranko: most people recommend not using DOT fluid 12 months after opening... You'll be fine putting some back in from a bleed bud. Once opened it will begin the hydroscopic process, doesn't matter if you bring some out and put some in.

I was also just stating that the hope bleed cup comes with a dot fluid container for 25£, no other reason. I use the metal bleed cup with mineral oil too.
  • 7 0
 Bleed cups are plastic because its much faster and easier to make plastic bleed cups.
  • 3 6
 @Tmackstab: wait, capitalism was the culprit all along?!?
  • 3 0
 Just make the adapter plastic? Rather than brass
  • 2 2
 @nskerb: STFU


Just kidding...Only just though.
  • 3 0
 The fittings are brass - as stated in the article. Brass is soft and won't strip aluminum or steel threads.
  • 3 3
 sure. make the cup 80% the hardness of the lever body....but! Shimano made their cup from hot Gouda, and thus it f*cking sucks ass. if you bleed 10 brakes a week, they last about a month.

This is a product that a trained mechanic should have no issue not putting a 2 foot breaker bar on to tighten properly. lol
  • 1 0
 This is for the mechanics mechanic. The guy (or girl) who drools over stuff like this.
  • 1 0
 @jomacba: I had a machinist buddy make me an adaptor from the Hope Alu. bleed cup to shimano. has worked for almost 2 years, not a stripped or damaged brake with it.

so nice.
  • 3 0
 @nickfranko: yup, seing the oil level is a major one
  • 3 0
 @Arierep: Extra 20bucks for one with a viewing window. But yea, that's right, not every bleed is a gravity bleed and we need to know how much pushed-from-the-calliper-up oil is in the bleed cup. I do realise that the amount of oil used in a brake line would never fill that cup in the one bleed but sometimes I like to push through multiple syringes worth to ensure all the old oil is removed, and for that process, id like to see how much oil is in the cup without letting go of the syringe to look down into the cup.
  • 1 0
 I usually just open my reservoir for bleeding so I don't quite have a purpose for such cups. But I also have the option to use a bleed port on the master (Magura Louise 2008 and Marta 2009) so I could use that if I want. The instruction is use an open syringe (so without the plunger) and it works fine. The advantage I see in using a narrow syringe over a wider cup like what's shown here, is that once you're done and still have some excess oil in the syringe/cup you can just put your finger on top, lift it off the master and empty the contents back in the bottle. Seems to me such a large diameter cup is much harder to seal from the top.

Syringes can be had for cheap at the pharmacy. I don't only use them for bleeding my brakes, but also for measuring oil for my fork. Surely someone can machine an alternative out of aluminium but I don't quite see the advantage.
  • 1 1
 @Nygaard: If you’re stripping bolts on your bike. You should probably have someone else do it for you. Just saying
  • 4 0
 Good point but here is the real kicker - YOU Actually want to strip out the braker lever as the cup is likely more expensive........
  • 1 0
 @dldewar: haha yeah, 79 moneys + shipping and duties to bleed a 30-60€ Shimano lever.
  • 1 0
 I'm still using the mini disc brake service kit from Magura which I got back in 2002 too or so. The cardboard box is all stained and falling apart, but I see no reason to replace it. If I'd get anything aftermarket, I'd probably get something from epicbleedsolutions.com. They also offer top cap spanners which appear laser cut rather than machined. It needs to be flat anyway and I don't see how anything machined can possibly be more accurate than something laser cut, especially in the corners of the hexagonal cut-out. It will still work perfectly well if they give it a bit more room there, but it won't necessarily be better than the laser cut product. Only more expensive.

But yeah, as the brake bleed can make or break the brake performance, why not do a group test of aftermarket bleed kits and compare them to the original kit as supplied by the brake manufacturer. If they're not considerably better/faster/more convenient then what's the point?
  • 2 0
 Man, if you are liable to stripping the threads with a metal bleed cup I don't know if you are cut out for bleeding brakes
  • 2 0
 @NorCalNomad: Hurtful. You are not inclusive of men that are experiencing Brownfinger. You know - when wrenching everything you touch turns to S#%T.
  • 1 4
 @vinay: the cups come with a plunger to seal the hole. Less effort that a syringe, you just shove that into the hole in the bottom, then unscrew it, drip free more or less. The cups are actually pretty good, just the plastic shimano ones wear out after a (not high enough) number of uses.
  • 87 0
 $79 CAD

Saved you a click
  • 25 0
 Geez, gonna have to win it in a contest at that rate...say, like that recent Advent thing. I hope they announce who won before summer is over.
  • 4 2
 It's in CAD!!! So, cheaper for the Americans, Europeans, and especially the Bits!
  • 3 0
 @noapathy: better to wait until after next Christmas, so they can kill two birds with one stone
  • 3 0
 @Mac1987: Maybe they're going to the once per decade for efficiency.
  • 1 0
 you da real mvp
  • 1 0
 @noapathy: gotta wait for a win it Wednesday where there's no winners and only losers.
  • 1 0
 $79 CAD for a TRULY pointless product.
  • 1 4
 @jptothetree: I wouldn't say it's pointless. Definitely on the pricey side. It's for the likes of dentists and rich folks that like to spend money where it's not needed - you know things that money makes things look bling when it looks like it's made from PVC pipes. Big Grin

Anyways,back to that pointless point, this aluminum cup does have it's place to try and make your brake bleeds. If it can eliminate that floating bite point on your calipers... (Oops - here we go again!)
  • 62 0
 Why stop at ALU?
I want machined Ti, anodized in 1 of 14 colours to better match my hubs.
  • 13 0
 Pfft - 3D printed, 6/4 Ti, oil slick anodized or forget it...
  • 3 1
 @ReformedRoadie: oil slick is PVD coating, so they'd have to be chrome dipped first, then coated for that ultra shiny finish.
  • 3 2
 Why not Ti and Carbon Fiber?
  • 2 0
 @CSharp: I want a platinum one, at the least!
  • 3 0
 @seraph: whatever it takes!!!
  • 3 0
 @seraph: Wait, it is? I was always under the impression that oil slick is just anodizing with specific voltages which correspond to specific colors.
  • 3 0
 @MaplePanda: The colorization of the titanium is through anodization. But if you want to do it on a different substrate (aluminum, steel, etc) you first have to PVD coat the part with titanium and then anodize it.
  • 4 1
 I want glass so I can see it spooge in
  • 46 0
 Remember that one time when you were bleeding the rear caliper, and you watched the fluid levels like a hawk through the plastic cup and thought "man this is inconvenient".
  • 3 0
 LOL
  • 15 0
 I like my Hope Aluminum bleed cup that cost me less than the Shimano Plastic set I had to buy for my partners bike
  • 2 0
 Ya, I have that one too, and it also screws into the Shimano lever.
  • 14 0
 His axle replacement for I9 Hydra hubs is absolutely bomber and way better than the stock aluminum thing that snaps if you look at it funny. Highly recommend.
  • 6 0
 Dude thank you for mentioning this. I had no idea that existed and I’ve broken the aluminum I9 axle sleeve thing twice now.
  • 1 0
 @BamaBiscuits: do you need to remove the cassette to check if this is broken or can I just look inside the axle bore? Does it develop noticeable play?
  • 14 0
 @skiboot1: You'll know when you remove the wheel from your bike and your cassette, freehub, and 1/3 of the hub axle all fall off onto the floor.
  • 2 0
 @skiboot1: yeah as @NoahColorado said the main symptom is your cassette with just fall off when you remove the rear wheel
  • 4 0
 oh hey wtf ive broken that exact part!
  • 5 0
 @NoahColorado: oh that sounds pretty sweet! I'm looking forward to that experience!
  • 1 0
 @NoahColorado: Ah yes I remember the first time this happened to me
  • 10 2
 Plastic is better suited to the purpose. But at least these are good looking, which is the point of them.
  • 7 0
 Used Pinner for a 32mm socket for my fork. Super friendly and easy to deal with. 5 stars on Yelp, would eat here again.
  • 1 0
 Little known fact, you can drill square holes.
  • 7 0
 Since you're all complaining about visability, they could just cut a slot into the side to see the fluid.
  • 3 0
 *machine* a slot, you mean. Cutting is for losers.
  • 5 0
 I love Pinner Machine Shop for making the stainless Hydra axle so my cassette doesn't fall off when the aluminum axle breaks.
  • 7 0
 I’m waiting until they make the clear aluminum version.
  • 1 0
 Sapphire is Aluminum Oxide, could at least make nice viewing window.
  • 6 0
 What's wrong with plastic
  • 12 0
 Too cheap
  • 7 1
 not expensive enough to match the new lines of $15,000.00 bikes that should cost 4K. Not just dentists lusting for these metal cups maybe 2 girls could use one cup
  • 3 0
 Not bling enough for @toolboxwars submission.
  • 1 1
 Plastic can't strip the threads on your brakes.
  • 1 0
 for a regular consumer, nothing, they'll last forever. Something like this makes more sense for a shop using the tool 100x more often. the threads on shimano bleed cups get loose when the plastic wears and leads to a messy bleed
  • 1 0
 @madmon: I truly wish I didn't understand that reference there. It's burned into my damn memory.
  • 1 0
 @jptothetree: sorry 2girlsonecup ew
  • 4 0
 Nice looking but maybe difficult to see the brake fluid level at a glance. I for one would probably push too much oil through.
  • 4 0
 Need one for Magura now, just to see how many turns can make before pulling the plastic threads completely out. I'm predicting 1.
  • 4 2
 Apart from stripping the threads, the other BIG problem is this is not transparent like the plastic cup, so you have no idea how much fluid is still in the cup. Often you need to be down at the calliper level, especially If you are doing something like a gravity bleed and cycle quite a lot of oil through the system. Draining the cup and getting air into the system is a royal PITA.
  • 2 0
 Why are the bear ears on the 32mm socket biased towards tightening rather than loosening? I feel like it's pretty rare that low profile top cap corners are removed when fitting compared to loosening.

Unless of course there is an entirely separate "loosening socket".
  • 5 0
 Dumb, wont be able to see thru them to know where your fluid level is at
  • 1 0
 Great point.
  • 3 0
 Exactly. Sometimes I am working the lever, holding the caliber over something and my head is below the cup. Need to be able to see the level.
  • 3 0
 not only is plastic better for level but transparent would be perfect as I like to watch the air bubbles float up, very satisfying Wink
  • 1 0
 Visual ASMR
  • 1 0
 Why do bike industry folks keep wasting their time with such worthless crap as this?
  • 1 0
 This is just workshop bling, doesn't do the job any better than a plastic one. Arguably worse because you can't see through. I just use a syringe with no plunger it attaches with a unf-luer adapter I got from an old Reverb bleed kit.
  • 2 0
 My hamfisted brother in law cost himself a SRAM flat mount caliper by mangling the threads trying to bleed his rear brake. I'll buy him this so he will need a new lever body as well.
  • 4 1
 As a full time suspension tech, that has worked for over a decade, this is probably the most pointless tool yet.
  • 2 0
 I've been waiting years for this. How many of my bikes will i have to sell to afford one?
  • 2 0
 Depends how much credit you have
  • 2 0
 You guys should note your Hayes Dominion support as they use the same threads/bleed kit as SRAM.
  • 1 0
 Who doesn't? I have owned brakes from SRAM/Avid, Shimano, Tektro and Formula and they all use the same thread. UNF nr 10. It seems to be an unwritten standard. Is there any brand that uses something else?
  • 1 0
 @ak-77: They say their Cup threads for Shimano don't work with SRAM and that you have to buy an adapter. I don't recall SRAM/Shimano compatibility since I have separate bleed tools for each. If all the threads are the same, why the adapters?
  • 1 0
 @Svinyard: The adapters for my Reverb have the same thread as my Formula brakes, but there is a knurled part on them that is just too wide for the adapters to fit nicely in the calipers. Maybe it is something like that? Or there is an o-ring on it which is only compatible which isn't compatible with DOT fluid. Although at this price and with shop use in mind, I would supply this thing with a fluoropolymer ring that can handle any fluid.
I haven't owned or bled SRAM brakes since they abandoned the Avid brand name. Have the bleed adapters changed since then?
  • 3 0
 Pinner is a great company! Born and bred in Whistler too!
  • 1 0
 the plastic ones work great until a co-worker grabs yours off your bench and strips out the plastic threads. HANDS OFF MY BLOOD CUP
  • 2 0
 Pffft. I only use carbon fiber bleed cups.
  • 1 0
 At what point does a de burr become a chamfer?
  • 1 0
 ^The question
  • 1 0
 Are gravity bleeds a good idea for all brakes?
  • 1 1
 They're the standard for almost all vehicles with hydraulic brakes. FWIW, the best bleed I ever got on my SRAM Codes was doing a quick gravity bleed on the lever, open top syringe at the top, closed syringe at the bottom.
  • 1 0
 2 brakes 1 cup (metallic)
  • 1 0
 I'm confused, the chamferless socket.... Has a chamfer?
  • 1 0
 Beautiful!
  • 1 0
 Pump pump pass.
  • 1 0
 CNC'd cup.
Below threshold threads are hidden







Copyright © 2000 - 2023. Pinkbike.com. All rights reserved.
dv56 0.046273
Mobile Version of Website