Thursday, 22 April 2010

Paddling (Upstream.)

I’m quite proud that I’ve managed to use the verb ‘paddling’ as both a metaphor and in a literal sense in the same post. I never claimed to be terribly normal….

In the literal sense, we now have a ‘flappy-paddle’ (do I need to credit Clarkson for that term?) and rocker assembly - two of the major components to be used in the rod-arrangement paddle shift system that we’re employing on the car. These aren’t just ANY old components however. They’re not made from steel or even aluminium. There are made of kevlar composite. Steve created a sheet of suitable material by building up layers of matting, sheet and resin. I’d love to tell you more about the process put it might as well be juju for all my knowledge of it. Anyway, I’m told that it is very light and should be more than strong enough to do the job. The sheet was then cut to shape by AndyW7de using a water-jet cutter. Here are the results:
The sheet was big enough to get couple of sets out. My paddle is the larger one. I’ve experimented with wheel sizes and have found that I don’t get on terribly well with tiny wheels. My wrists are increasingly prone to aches and pains (no lewd remarks necessary!) and I just feel a bit more comfortable with a 12” wheel. The intention is to finish the edges either with gel coat or possibly by polishing with cutting compound. I did the same on the carbon back panel on my MNR with good results.
I use the paddling upstream metaphor in relation to Steve’s activity on the chassis of late. I really do not envy him trying to find time to work on the car and help look after a new baby and work full time. I’m in no rush so everything is fine my end – I just wish I could help a bit more. The two Ds, distance and dissertation, don’t lend themselves well to this unfortunately.

That said, I’m hoping to have a day off studying to go to Brands Hatch on Sunday to see the RGB race and to have a look at some of the new cars that are joining the Championship. Hopefully, Saturday’s race will be without incident and I won’t miss anyone.  My old comrades from the Locost Championship are there too so it should be a good day.


Tuesday, 13 April 2010

Top ball joints. Or not.

‘Plan A’ to connect the upper front wishbone to the Cortina upright had been the usual Locost method of using a ball joint in the form of a drag link or track rod end from a Ford Transit. We’d also intended to use a ‘quick camber adjuster,’ essentially a threaded sleeve that sits inside a 1” inside diameter (ID) tube and allows you to move the ball joint in and out without removing any parts. However, there has recently been some discussion about the fragility of these items following a total failure on a road car. In addition, 1” ID tube was proving frustratingly difficult to obtain. These considerations, along with the fact that the rest of the suspension uses rose joints, were enough for me to look at replacing the upper ball joint with a suitably tapered pin and rose joint set up.

My MNR had used this system. However, I had a feeling that they no longer offered the parts to use the Cortina upright – in the back of my mind I was pretty sure that I’d had the last set for my old car. I contacted Chris Nordon to see if this was the case and indeed it was. My next port-of-call was the ever helpful Matt Gilmour at Procomp. I had a chat with him about design and joint heights and he made it clear that he could make the parts. However, I was also pretty conscious that he and Ivan are up-to-their-eyes in work. No surprise – they really do sterling work. So, I started to investigate alternatives. I had a look at some of the Westfield specialists like CAT Motorsport but had little joy. I then found a post on the Locostbuilders forum by someone calling themselves ‘mintici.’ The post showed a very similar set up that had been machined for a Westfield. On further investigation, it turns out that ‘minitici’ is Douglas Anderson, proprietor of Westgarage Engineering Services.  Douglas usually specialises in chain drive differentials, carriers and associated parts for mid engined cars. However, it’s clear that he can turn his hand (pardon the pun) to most things.

After some efficient communication via e-mail, I sent one of my Cortina uprights to Douglas so that he could be sure that the taper was right. I also sent him the relevant measurement from Steve’s suspension drawings. The great thing about this setup is that the height of the top joint can now be changed relatively easily to aid fine tuning of handling characteristics. Good news all round. Douglas’ pro-forma invoice suggested that delivery would take up to 4 weeks. No great problem for me. However, just two days after posting the upright I received some pictures of the first pin, top-hat and rose joint assembly. It’s clearly a relatively simple job for Douglas and I’m likely to get the parts much sooner than expected.

As Douglas says in his e-mail, “The pin and top hat have been shaped to allow maximum articulation of the rod end.” This can clearly be seen in the pictures.

One other thing that the pictures show quite clearly is the casting marks on the upright. If I was in any doubt before, these are definitely getting powdercoated now. I know that it’s a race car, but cosmetically that just will not do!


Thursday, 1 April 2010

Safe and Sound...

Few words this time around; just a couple of snaps.

Cage from 'Caged' - rear supports yet to be installed:
And an apparently foggy shed:

If anybody reading this has access to 7/16" high tensile bolts with a 2" shank/shoulder and overall length of 2.75"-3" could they please let me know?  The only ones I've manged to source would cost over £15.00 each - and I need 22 of the things so that just isn't going to happen!

Thanking you!