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The Birth of a New Product - Hex for Hope PF Bottom Brackets

Posted by Jim MacPhail on

 It's always exciting to release a new product, to take something you've been working on for a while, to open it to the world and see if anyone else thinks that it's worth having.  This new tool is simple - there's nothing groundbreaking in it - what you see is what you get. And it is, admittedly, a niche thing, but hopefully it'll help a few people out.

But rather than just announcing the arrival of the new product, I thought it would be fun to share the process that lead to it's arrival.

So what is it?  

Well, it's a big hex for installing Hope PF bottom brackets.   Simple.

Why would we spend our time thinking about something so simple and so obscure?  Well, as usual, it started with us trying to solve a problem that we encountered in our own biking lives.  

Hope make great gear.  Having run through several of the big-manufacturer's bottom brackets in quick succession I was looking for something up to the challenge presented by the Scottish climate.  I turned to Hope, and as usual, found myself impressed with the design and the quality of manufacture of their bottom bracket.

But there's a problem:  unlike most press fit bottom brackets, which come in two parts and are simply pressed in from either side,  the Hope PF unit's two parts screw together inside the bottom bracket shell. There's a good reason for this.  Many people complain that their PF bottom brackets creak (how often do you read bike reviews lamenting the decline of the old thread-in style BB?).  The reason that some press fit BB creak is that they move by a tiny amount inside the frame. Hope's solution is to screw the two halves of their bottom bracket together, clamping the BB into the frame and eliminating movement.

To fit the Hope PF41 or PF46 bottom bracket you need a rather large hex: 31mm and 26mm are somewhat beyond the range of your average set of allen keys!  Of course Hope realise this, so offer a tool for the job. Unfortunately it comes at a cost of £45, which from me was a bitter pill to swallow, on top of the £90 that I had just paid for the bottom bracket.

When I bought my Hope BB several years ago (still using it, with one bearing change!) my solution was to file a crude hexagon out of a scrap of steel that I had lying around.  This was before I had a workshop at my disposal. I drilled a hole in the centre and, with a large bolt and a nut tightened on each side of the hexagon, found enough purchase to install the BB.

Fast forward a few years and a friend bought a Hope PF BB and encountered the same problem.  ‘Don’t worry I told him, ‘I’ll make you a tool’. Now with lathes and a milling machine at my disposal, I was in a position to do it properly.  If I needed one, and he needed one, then surely others did too. I’d use it as a prototyping exercise and see if there was any demand.

Naively I had thought that I might be able to purchase a length of hex bar off the shelf in the required size.  This turned out to not be the case; instead I milled a round bar down to a hex bar of the required size. This bar was then sliced into flat hexagon discs.  

To provide the purchase to turn the hex, I first tried the trick that I had used the first time, a large bolt with nuts tightened either side.  This proved to be unreliable, the bolt slipping if the BB was screwed tight into the frame.

In the end I settled on a simple square hole to drive the hex.  This is an elegant solution if you have a ½” ratchet spanner to clip the hex on to. 

After some testing and adjustment to the design I had half a dozen tools to test the market with.  These sold slowly but steadily. There was never going to be a fortune to be made but if they could be made economically they would cover their cost.

The method that I’d used to make the prototypes was great for making a few testers, but was too labour intensive and too wasteful of materials to be economic for production.  Instead I sent enquiries out to several laser cutting companies, and found one that was able to cut 5mm steel plate with the required tolerances.

A couple of weeks later I have a bag of tools in both the sizes required by Hope’s excellent BBs.  Time to get selling!

If this sounds like something that you might need, you can buy it here.

 

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