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PostPosted: Fri Dec 01, 2017 11:11 am 
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As it seems to be fairly impossible the buy a pair of those (and for a price I am willing to pay... :facepalm: )
But they look so damn nice. I thought to myself, I'll make my own.

I already souced the materials needed to build a few.
But I would need some dimensions to verify what I derived from the photos I found on the interwebs.

Image

Most important would be the distance of the roller axle to the brake stud, measured from middle to middle. (Nr. 2)
The other dimensions would be nice to have.

No need for super high accuracy as I suppose the brakes were made "imperial" and I would make my verision metric. :D


Image


Last edited by Thias on Tue Dec 05, 2017 8:47 pm, edited 2 times in total.

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PostPosted: Fri Dec 01, 2017 11:55 am 
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I used to have a set of Marinovator Decelerator but sold it to a guy in Germany.
If memory serve me right the arms was so short the wire loop barely cleared the top of a 2.1'' tire. So if you make some ad a couple of centimeters!
I believe the later CheapTrick brake had taller arms for this reason, and it also added to the brake force making it superior to the Decelerators.
Why not make some extra set's an sell? I'd buy them for sure! :P
Here are some pics and manual for reference and please let me know how they turned out!


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PostPosted: Fri Dec 01, 2017 11:57 am 
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Location: Playa el Stockholmo, Suéco
Manuals:


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Marinovative Decelerator manual1;1.jpg
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Marinovative Cheap Trick manual2-s.jpg
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PostPosted: Fri Dec 01, 2017 12:37 pm 
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@donpedro: Yes, we Germans seem to like those.

I might do a few extra ones. But not until I am sure they are safe will I sell them. Thats always the problem with selling self made stuff. You have to guarantee for them being safe. Witch is virtually impossible.
Thank you for the pics. But they don't really help as they miss actual dimensions. I do have the relative dimensions already.

About making the arms longer: I had thought about that. Actually I plan on making one set with 3 or so holes in different heights to mount the rollers on. Just to test out the effect on braking power. But control is also a factor here.


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PostPosted: Fri Dec 01, 2017 1:03 pm 
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If you have a set of Koolstop pads you could measure the length and with the measurement from the pictures calculate the length of the arms. Just don't ask me how! :wink:


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PostPosted: Fri Dec 01, 2017 1:28 pm 
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... and taking into account the lens distortion, the tilt of the parts in the pics and the non-precise measurement on screen (all those errors are multiplying) I get all the dimensions +/- 5mm... ;)
I really did that already. And with those measuements I ordered the material I will make the brakes out of. Things like ball bearings, hex aluminium stock and so on. The only thing I am missing right now (that I am aware of) is the actual height of the roller. And maybe the diameter of the roller. The rest is more or less fixed.


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PostPosted: Sat Dec 02, 2017 6:59 pm 
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I have CAD drawings of these brakes at home.
I can give you diamensions but can’t send you the drawings without the owners permission (can’t remember who owns the drawings).

I had to quote for making a bikes worth completely from titanium (except the springs), I couldn’t find any titanium hex the right size so would have to had machined it hex from round bar, a lot of waste of material and a lot of time.


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PostPosted: Sun Dec 03, 2017 8:49 am 
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That would really nice.
Those hex on the original brakes were aluminium, right?


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PostPosted: Sun Dec 03, 2017 10:21 am 
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For the armchair observer this thread is getting more more interesting with every post.

Please keep posting any progress, last good thread like this was the Hydrocoil conversion of a Judy FSX.


Last edited by Retro Spud on Sun Dec 03, 2017 11:04 am, edited 1 time in total.

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PostPosted: Sun Dec 03, 2017 10:45 am 
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Yesterday, I started making the pulleys. On the pic, I am parting off one of the pulleys. The ball bearing is pressed in already, because I did that using the tailstock.

Image

The pulleys seem to be the easyest parts on those brakes, so I started with those.

Next will be the arms. I will make them out of stainless steel tubing, because I have them in stock. May well be I repace them with titanium later on. But this brake is a prototype. It is quite possible I will make a few mistakes. So using titanium in this stage would be a waste...

My biggest Problem with this whole build is my limited machinery (and maybe knowledge ;) ). I don't have a mill. So I have to make all the parts on my small lathe. Even the drilling. As my old chinesium drill press is a mess in terms of precision...


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