Park Tools DAG o-ring size

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probertsqbe
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Joined: Fri Feb 22, 2013 1:27 pm

by probertsqbe

I own a Park Tools Derailleur Alignment Gauge ( DAG) 2.2. Both of the o-rings have perished and I need to buy a couple more but am struggling with the size.

According to tech spec on the Park Tools web site http://www.parktool.com/assets/doc/prod ... -14-13.pdf

The part number for the o-ring is 1626-2 but I haven't been able to find someone online who sells these.

Anyone any other idea the size and f the o-ring or where I can purchase a replacement? Google hasn't helped this time.

I'm UK based.

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Trkorb
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by Trkorb

I have used a cable tie to replaced the o-rings, works pretty well.

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bikerjulio
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Location: Welland, Ontario

by bikerjulio

I doubled up on a small elastic band.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

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BRM
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by BRM

These O-rings are nothing special. Go to your local plumber or do DIY store.
Or buy an assortiment on ebay (china)

What you need is calipers, makes it easy to measure yourself things in detail. In this case the pin where the O-rings need to be pushed on. Calipers are an essential tool, everyone should have in home.

BTW the system with the O-rings to keep the pin in place is a bad design.
You want to have a stop on it that is easy to set the pin fixed (and loose), and is SOLID.

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Calnago
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by Calnago

@BRM: have you actually used the Park DAG tool? The O-Ring is a perfect design for that application. While calipers are great to own, they are of no use in this application.
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ManekiNico
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by ManekiNico

Just measured mine for you. The outer diameter of the indicator pin is 1/4" (±6 mm) . The inner diameter of the o-ring is about 3/16" (hard to measure without stretching it). In any case, you want the o-ring to be smaller than the indicator, so 3/16" (±5 mm) is probably about right.

I’d suggest using a rubber grommet rather than an o-ring. The wider grommet won’t roll out of position as you move the indicator back and forth to clear the chainstay. Something like this: http://www.amazon.co.uk/dp/B00SWNTXSC.
Mom: He was very sickly until he started riding around on that bicycle.
Dad: Yeah... well... now his body’s fine, but his mind is gone.

sungod
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by sungod

as above

or you could try a pack like...

https://www.amazon.co.uk/Assorted-Rings ... 6040360860

there're plenty of others on amazon, also ebay

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BRM
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by BRM

Calnago wrote:@BRM: have you actually used the Park DAG tool? The O-Ring is a perfect design for that application. While calipers are great to own, they are of no use in this application.


This forum is a specialised forum, people talk about exotic materials and things in detail. Its an advanced forum . . . . . you should think. However frequently I read people want to know the size/diameter of a bolt or something similar. Come on. I expect people that maintain their bike and repair other things have a toolbox with standard tools. One of the standard tools to measure are calipers. When you dont have?, you definitely need to buy one and learn to use.

Again O-rings cost nothing. And no need to get the same outer diameter. Just go to the sources I mentioned.

- - - - - - - - - - - - - - - - - - - - - - -
Yes I know the Park Tool DAG II. And it has a flaw and that is the design with the O-rings to keep the indicator pin in place. It is too easy be moved without noticing because there is no scale on the pin in first. When the pin could be fixed with a stop on the outer side it would work already better. Like a 2 cm metal tube with fits over the feeler and can be fixed on the side with a wingnut/knob.
Or just as you can fix calipers, lol . . . . . .

So this DAG is not perfect at all.
-It misses a scale on the feeler
-It misses an adjustable solid stop

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Calnago
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by Calnago

Hmmm... Well I guess I disagree. It's fine and I prefer the easily moveable and adjustable o-rings to a more locking type. It adjusts easily and you don't put any force on it that would move it out of position during proper use. It does not need to "lock".
And the discussion of calipers is completely irrelevant to this thread.
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probertsqbe
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by probertsqbe

Thanks for all the advice. I'm going to order the o-rings and try the grommets which may be more robust. The digital calipers are on the wish list but couldn't justify them for this query.

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BRM
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by BRM

Calnago wrote:Hmmm... Well I guess I disagree. It's fine and I prefer the easily moveable and adjustable o-rings to a more locking type. It adjusts easily and you don't put any force on it that would move it out of position during proper use. It does not need to "lock".
And the discussion of calipers is completely irrelevant to this thread.


Whats your problem you don't understand the flaws while I explain it in basic word for you?
Unwillingness, stubbornness? Or is it Lack of insight, interpretation, visualization and experience with tools?.
Probably its your mind, and you only can follow your own ways in thinking but as soon people come with a vision fromout other direction its abracadabra for you. Its just the way you think, just the way you are. Just do an attempt to follow my words exactly as written.

With the rubber O-rings there is too much room for moving the feeler and when its only one mm off only, you already come into problems. Its not well thought out. If you think it is, you simply have no understanding of engineering and no understanding about quality levels precise tools needs to conform with, sorry.
There is room for error and no way to see it because there is no scale either. (like on the Shimano tool for instance)

To bring in calipers was not irrelevant at all?. Well the TS wanted to know the exact size of the O-rings so it is very very relevant.

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BRM
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by BRM

probertsqbe wrote:Thanks for all the advice. I'm going to order the o-rings and try the grommets which may be more robust. The digital calipers are on the wish list but couldn't justify them for this query.


I can't look in your wallet what you have to spend. But when you need to wait till you can justify such a bought, you maybe can wait for ever.
See it different, you don't buy such a tool for one particular application.When you have one you can use it for all kinds of things when it comes out for you. I use mine often several times in a week for all kinds of things. When you take care for it, so not dumping it in a toolbox but lay it aside in a closet orso, you can use and profit from it for a very loooong time.

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Calnago
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by Calnago

Ok.
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bikerjulio
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by bikerjulio

probertsqbe wrote:Thanks for all the advice. I'm going to order the o-rings and try the grommets which may be more robust. The digital calipers are on the wish list but couldn't justify them for this query.


Perfectly adequate digital calipers can be had for <$20.

I use mine all the time.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



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BRM
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by BRM

With this kind of tools you do almost a lifetime, so dont set focus on price only but set quality on top.
Better one that is bit more expensive and suits you really, than a cheaper one that is mediocre in use.
Because remember, you will buy it for years and years of use.

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