1:8 McLaren Honda MP4/4

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ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Hi everyone, back again with another update. Over the next few weeks I'll be covering the final assembly of the model but I've also still got the decals, the display and the driver to do. Should hopefully be receiving the first driver model tomorrow so quite excited to see that, then depending on how it goes I'll get the 2nd one printed as a spare/altered scale depending on if I need to file it down much or if it looks disproportionate.

So this weeks update will be the first from issue 20, which is the final issue of the subscription (sad sniffles intensify :( )

So firstly stage 68, assembly of the electrical system. Parts supplied with this issue were: left radiator outlet duct upper (1), radiator outlet blanking panel (2), left radiator outlet duct lower (3), right radiator outlet duct lower (4), radiator outlet blanking panel (5), right radiator outlet duct upper (6).
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Parts needed from previous stages were:
- Cable tie tape (Stage 55)
- CDI unit, telemetry unit, wires E & C, connector sprue, electrical system part A, electrical system part B (Stage 66)
- Instrument panel (Stage 67)

Firstly, 68.1 - connecting wire E to instrument panel. A 125mm of wire E was glued to the rear of the instrument panel, nice and easy.
Front:
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Back:
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And then a connector was removed from the sprue and glued to the other end of the wire just attached to the instrument panel. Care was taken to orientate the connector the right way, with the 'short' end on the wire.
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Next, a 100mm length of wire was glued into the free end of the connector above. Now this is something that seems entirely pointless as it could've been done with a single 225mm length of wire. I would've thought the connectors would make more sense as they've been used elsewhere on the model in situations where wires from different locations need connected but ohh well, maybe it's true to the actual car.
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Following this the long length of the wire attached to the electrical system part A was taped temporarily to the end of the wire E coming from the instrument panel.
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And this was then bound with 10mm lengths of cable tie tape (at weirdly specific intervals: at the connector, 165mm from the taped end and 185mm from the taped end). The tape was cut with the knife using the pressing technique described in my last update instead of a traditional drag cut to reduce fraying edges. It was awkward to attach the ties due to the natural elasticity of the wires pulling the tape apart, and also obviously due to the small level of detail.
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Next 68.2 - fitting the seat, electrical system part A and the instrument panel. Turns out I also needed the monocoque assembly which wasn't listed in the earlier parts needed. Firstly a 200mm length of wire C was cut and glue was applied to one end and then fitted to the corresponding hole on the throttle cable bracket on the monocoque and cable tie taped to the monocoque itself. Note, the seatbelts below are dry fitted which is why they look odd and also disappear in the following photos.
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After this the seat was dry fitted into the chassis, and the wire was bent around it so that it protruded through the holes in the seat against the monocoque, backmost hole first.
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This was then cable tie taped to the inside of the monocoque, tape was just as awkward as other times using it again to the springiness of the cable trying to pull it away from the monocoque. I ended up having to do these with tiny dabs of glue as the adhesive on the the tape just wasn't holding, and when I tried to reposition it, it ended up pulling the tape off the top of the monocoque, so again these had to be fastened down with tiny dabs of glue which seemed to do the job.
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After this the seat was removed and the electrical system part A was placed on the pins on the monocoque under the seat. The magazine then suggested feeding the hoses through a tiny hole in the monocoque (visible in some photos below) and then gluing the electrical system part A onto said pins. In practise there was no way to do this as I could not physically work out a way to feed the wires into the hole with the electrical system part A loose, it needed an anchor point to feed them from. It was also backwards in the magazine. The hole in the magazine was on the left hand side, as were the direction of the cables, but on the actual model they were on the right. I managed to do it and get the wires through the hole by gluing the electrical system part A to the monocoque first, and then pushing the wires through the hole with needle tweezers. This was still very very difficult, I'd actually rate it as one of the most difficult aspects of the model so far just due to how awkward it was to hold the model in position without damaging any of the finer more delicate aspects, light the area I needed, see into the area and also somehow use the tools at hand to get the wires through the hole. So to sum up I needed at least 3 hands, a 20mm diameter head or X-ray vision haha, unfortunately I don't have any of these qualities so I had to make do with my clumsy hands and balancing my phone light in various creative ways.

Extract from the magazine clearly showing the hole on the left (can see the gearstick on the right for orientation):
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And how mine ended up after having glued the electrical system in place, but prior to feeding the wires in:
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And after feeding the wires in, can clearly see the hole is on the right:
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And a couple shots from underneath the monocoque to show the wires coming through the monocoque hole.
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The wires themselves were just tucked into the underside of the monocoque next to the suspension arm.

Photo below showing the current stage (read: mess) that the electrical system is in, with the instrument panel ready to be attached.
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And then the instrument panel was glued onto the monocoque via the slot in the monocoque and ridge on back of the instrument panel. I had to check this a lot as the instrument panel covered the brake balance adjuster. I couldn't really find any reference photos of that area in the magazine, but based on the fact the top of the ridge was aligned with the top of the slot it meant there wasn't really anywhere else it could go. There was also no panel gaps between the instrument panel and the monocoque as seen below which again indicated to me that I was right I think.
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The trailing wire was then bent along the side of the monocoque, and the seat was re-fitted as shown below. After the seat was dry fitted the cable was cable tie taped along the side of the monocoque, the same problems presented as earlier which again was solved with dabs of glue on the ends of the cable tie tape. I didn't want to just glue the cables directly for fear of leaving that white superglue residue that happens.
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And shown here with the seat removed again just to show the path of the wires:
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The trailing edge was then cable tie taped to the top of the monocoque, again dabs of glue were used to prevent them springing up.
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And with the seat back in place (still dry fitted).
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And that's it for 68.2. Next, 68.3 - fitting the electrical system part B, the CDI unit and the telemetry unit. First, glue was applied to one end of the battery cable attached to the CDI unit which was then pushed into the connector coming up the side of the left radiator. (This is what the connectors should be used for in my opinion lol, not as extenders to pad the steps.).
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And then the CDI unit itself was glued onto the radiator housing and the trailing cable tucked behind the intercooler.
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Next the telemetry unit was glued to the right radiator housing and the wires were bent and arranged as shown below and cable tie taped in place.
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After this the electrical system part B was glued to the top of the monocoque...
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And the wires were bent around as shown:
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And that's it for todays update. Hard to believe there's only been 3 steps today haha, sorry for the long windedness of it but I was just trying to capture everything and it was quite fresh in my head so wanted to get it written down haha!

Thanks for reading, as usual if there's anything you want to see in more detail just let me know.

Cheers,

Alex

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strad
271
Joined: Sat Jan 02, 2010 12:57 am

Re: 1:8 McLaren Honda MP4/4

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Nearing the finish line.
Great work and problem solving as usual.
I would never have had the patience. :wink:
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Hi guys, quick update today. Received the prototype driver model and it's brilliant. Exactly what I needed, only problem is I got my estimates a little bit wrong on the scale side so it's ended up massive :lol: . See photos below for what I mean, in relation to the model, it's really quite comical to be fair haha. I measured the diameter of the steering wheel at 33mm and the gap between the drivers hands at 53mm, so I've emailed the company back to print the 2nd one at a 1.61 x reduction factor, hopefully this should scale the entire driver correctly. Kind of a bit of feeling around in the dark for this to be fair, I'll do something with the V1 prototype, turn it into a different project or something.
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That's it for now. I haven't had time this weekend to get any work done on the model itself, so the next update will probably be in 2 weeks.

Cheers,

Alex
Last edited by ajdavison2 on Tue Oct 20, 2020 8:46 pm, edited 1 time in total.

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strad
271
Joined: Sat Jan 02, 2010 12:57 am

Re: 1:8 McLaren Honda MP4/4

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Well it was a pretty good guesstimate. It's a good looking model...just a bit big.
How did you arrive at that reduction?
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Hi Strad, yeah the model itself is spot on, just needs a spot of sanding and then painting as best I can to match Senna's overalls. Got the reduction factor by dividing the distance between the hands by the actual diameter of thr steering wheel. So 54mm/33mm = 1.66. They've sent me back the rescaled model and now the widest part at the shoulders is 48mm with the cockpit opening being measured at 55mm so it should be perfect once I receive the updated one.

ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Would also like to note that obviously the model isn't designed for the car. It's a generic model downloaded from an open source CAD site so it was always going to require some tinkering to get right, difficult when I don't have the software to do it properly, maybe if I could've seen it on screen myself I could've avoided printing the first one too big, but ohh well. I've already got plans for that one now haha.

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strad
271
Joined: Sat Jan 02, 2010 12:57 am

Re: 1:8 McLaren Honda MP4/4

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no no, don't misunderstand.. is great just a tad big.
Not being overly smart, I would probably have measured his butt as compared to the seat. However I am not noted for my skill in such areas. I can measure twice and still cut wrong. :lol:
You've done a great job.
I'm glad my wife was hesitant about me buying one of these back when I was on a model building kick.
As I have said it would sit unfinished having beaten me some time ago. Having seen me struggle on a couple of Lotus' and a few Ferraris she saw the future. LOL :lol:
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Would've been too difficult to scale it correctly from the butt as the seat is so irregularly shaped, I needed a linear dimension, hence my decision to use the steering wheel, just wish I had the foresight to do that initially. I think my mistake stemmed from trying to scale the overall height from head to toe, but I mis-communicated this and because the model is in a reclined position it stretched the overall height correspondingly.

I've already got a plan to get him to fit the seat, I'm going to completely flatten the back of the model and then take a mould of the seat with putty and cling film (clear plastic food wrap for our overseas readers) and I'll then bond this mould to the back of the driver and it should mean it'll sit perfectly in the seat.

I've done the mp4/23 previously but not to as high as a standard as I have done this model to. Less overall care was taken and stages were rushed etc.

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strad
271
Joined: Sat Jan 02, 2010 12:57 am

Re: 1:8 McLaren Honda MP4/4

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already got a plan to get him to fit the seat,
Ingenious idea. =D>
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

ajdavison2
ajdavison2
31
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

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Haha we'll hold off on that until we see if it works or not.