1:8 McLaren Honda MP4/4

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
ajdavison2
ajdavison2
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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).
Image

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:
Image

Back:
Image

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.
Image
Image

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.
Image

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.
Image

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.
Image
Image
Image

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.
Image
Image

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.
Image

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.
Image
Image

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):
Image

And how mine ended up after having glued the electrical system in place, but prior to feeding the wires in:
Image

And after feeding the wires in, can clearly see the hole is on the right:
Image
Image

And a couple shots from underneath the monocoque to show the wires coming through the monocoque hole.
Image
Image

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.
Image

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.
Image
Image
Image
Image

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.
Image

And shown here with the seat removed again just to show the path of the wires:
Image

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.
Image

And with the seat back in place (still dry fitted).
Image

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.).
Image

And then the CDI unit itself was glued onto the radiator housing and the trailing cable tucked behind the intercooler.
Image
Image
Image

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.
Image
Image

After this the electrical system part B was glued to the top of the monocoque...
Image

And the wires were bent around as shown:
Image

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

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

Re: 1:8 McLaren Honda MP4/4

Post

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
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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.
Image
Image
Image
Image
Image
Image
Image

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.

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

Re: 1:8 McLaren Honda MP4/4

Post

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
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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.

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

Re: 1:8 McLaren Honda MP4/4

Post

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
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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.

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

Re: 1:8 McLaren Honda MP4/4

Post

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
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

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

ajdavison2
ajdavison2
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

HI Guys, it's been a while since the last update and I'd like to report on loads of progress but I haven't got much to show. I've gotten some more of the car itself done and some more work on the driver. I've actually put the car on hold for the time being until I'm happy with the driver, anyway, all will be explained below.

I'll cover the progress on the car first. This weeks car update will be stage 69, assembling the body cover. Parts supplied with this stage were: Cockpit cover (1), rear rollhoop upper (2), kill switch (3), right side mirror (4), left side mirror (5), gearbox oil cooler duct (6), mirrors x 2 (7), tail light (8), mirror label (9) & plate label (10).
Image

And some closer images of the details:

Kill switch:
Image

Roll hoop and kill switch:
Image

Mirror covers and mirrors:
Image

Plate label:
Image

Parts needed from previous stages were:
- Rear cover, engine cover & engine cover labels (Stage 67)
- Outlet duct parts (Stage 68)

So first up stage 69.1, assembling the body cover. The body cover components were laid out to get an idea of the assembly.

Image
Image
Image

The rear cover was then glued to the engine cover. There was small rivets cast into the body to help fit them together. I initially done this with plastic glue, but the elasticity of the plastic bodywork prevented the body from holding at the extremities so I glued as much of it as I could with plastic glue and then turned it over and dotted the pins with superglue which kept it secured which you can see in the third photo below.
Image
Image
Image

Following this the cockpit was glued to the engine cover using the same method, superglue on the pins.
Image
Image
Image
Image
Image

Next the gearbox oil cooler duct was glued to the rear cover.
Image
Image
Image

After this the engine cover labels were required:
Image

One label was cut out, care was taken to get the right and left ones on the correct side.
Image

This was then peeled back and pressed to the engine cover, the labels were really adhesive so I only really had one shot at this otherwise it would make a balls of it. Overall though it worked out fine. care was taken to align the black label in the fine space between the the bottom of the radiator inlet and the very bottom of the bodywork, with no or as little white showing as possible.
Image
Image
Image

And likewise for the otherside:
Image
Image
Image
Image
Image

Next the other engine cover labels were applied to the front and rear of the bodywork:
Rear before:
Image

Rear after:
Image

Front after:
Image

Next up stage 69.2, fitting the outlet ducts. First the radiator outlet ducts were prepared:
Image

Then the outlet duct upper was glued to the outlet duct lower on both ducts:
Image
Image
Image
Image

The first duct assembly was then glued to the underside of the engine cover.
Before:
Image

After:
Image

And some other views:
Image
Image

And the other duct:
Image
Image

From the outside:
Image

Front:
Image

Back:
Image

front 3/4:
Image

Next was 69.3 - assembling and fitting the mirrors.
Firstly the tail light was ran over with my knife to take the flash off.
Image

Then the tail light sticker was removed from the plate labels (one of the circular silver labels on the plate label sheet) and stuck to the tail light. It was easier to cut it square and trim it using the tail light itself rather than cut it circular. So below the square stuck to the light:
Image

And trimmed, you'll notice the little scratches:
Image

These were simply painted over with some black gloss model paint I had.
Image

Following this the mirrors were assembled, the magazine suggested sticking the labels to the mirrors and then the mirrors into the housing, but I decided to stick the mirrors into the housing first and use the housing as a guide for the stickers themselves.
Mirrors and labels:
Image

Right mirror housing with mirror fitted:
Image

Right mirror with mirror surface stuck:
Image

And the left, you'll notice there's a slight visible seem on the left mirror (the top of the mirror as pictured, the line on the bottom is a reflection of the mirror housing in the mirror). I messed up the sticker so had to trim a new one out of the excess on the mirror sticker sheet and graft it on. It's only really noticeable if you're really looking for it, so as usual I'm fine with the countless mistakes I've made on this as long as I cover them up enough haha.
Image

The mirror assemblies were then glued to the engine cover:
Image
Image
Image
Image
Image
Image

Lastly for this stage, the kill switch was glued to the roolhoop. Care was taken to align the fin correctly, you'll notice from the photo at the start of the post that the fin isn't squared, it's more like a parallelogram, or a rhombus. The kill switch had to be 'pointing' upwards, I use quotes as it is only slightly inclined upwards.
Image
Image
Image

And that's it for the car updates. I'll just quickly run through where I am with the driver now.
So, I received the 2nd version of the model and it's much better scale wise than version 1. See below for comparison shots:
Image
Image

And in relation to the chassis it looks big again but believe me it's a much better scale.
Image
Image
Image

And shown in the seat, here you get a much better idea of the correct scale.
Image
Image
Image
Image

And roughly seated in the chassis.

Image
Image

And through the engine cover, again here I think the scale of it based on the helmet looks good for the model.
Image
Image
Image
Image
Image

Obviously he doesn't fit at this point as it needs trimmed/sanded etc. This was always going to be the case as it was never designed for the model. The company does offer laser scanning, articulated joints and professional custom CAD but we'll be talking well into the hundreds of pounds for that so it would start to be disproportionately expensive in relation to the model, the 2nd model cost me £18 (+£45 for the first one due to me messing up the scaling) and then I bought about £20 of basic modelling equipment like saws, various grit sand paper, paints, putty, wire (for my own articulation idea) and tape and I'm just going to work it into shape myself using hand modelling techniques.

To get the back of the model/seat mould I covered the seat in plastic wrap:
Image
Image

This was then filled with modelling putty:
Image

And smoothed/pushed into the seat to mould it:
Image

This is still drying at the time of writing (3 days after moulding) and there is still a little bit of flexibility in the putty in the middle of the seat, the outsides where it is thinner has dried to a kind of poly filler quality, I'm not sure what it's known as in America or other countries, but it's the white stuff you use to fill holes in walls. Can easily be sanded, painted etc.

Anyway, the driver model was sanded down, you can see the lines are vastly smoothed out.:
Before:
Image

After:
Image

And then the limbs were separated in preparation for making him fit the cockpit:
Image
Image
Image

It's a rough enough job at the minute, but I've got confidence I'll get it working. I've got plans B and C ready anyway just in case, but for the time being I'm going with plan A.

And that's it for this weeks update, as mentioned at the start progress on the car will be paused for now until I get the driver sorted, which I hope to have done next weekend. I can then get to finishing the car and working on the display.

Thanks for reading, if you want to see or know anything else just let me know as always.

Cheers,

Alex

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

Re: 1:8 McLaren Honda MP4/4

Post

Bravo Alex.
Great work. I bet it's far better than the average assembler did.
I also bet that most of the errors you talk about, only you can see and other wouldn't notice without you pointing them out.
More than ever I can't wait to see the finished product.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss

ajdavison2
ajdavison2
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

Cheers Strad.

So, quick update this morning. Funnily enough as predicted I f**ked it again haha. I released the seat from the mould and sanded the edges off easy enough, the moulding process actually worked perfectly, no damage to the seat or putty stuck to it, see below for photos of mould removal.

Image
Image
Image

And the mould in the seat:
Image
Image
Image

And the sanded down mould:
Image
Image
Image

Problem I had is that the seat is a flexible rubber material, so while the mould fitted the seat perfectly it ended up being the wrong shape once the seat was dry fitted to the chassis. So when the seat is fitted to the chassis it bends inwards to almost clamp it in place, meaning when it's removed from the chassis it 'opens' the radius. This means that the mould has a larger radius than the seat when it's sitting in the chassis so doesn't sit right.

So I've moved onto, lets call it plan A2 as my backup was something totally different. What I did was trim the body down further so just the upper torso and helmet was in the chassis. I dry fitted this with the belts, seat and steering wheel in place as well as the engine cover. I think this confirms that the scale is correct at least.
Image
Image
Image
Image

Also dry fitted with the arms squeezed in.
Image
Image
Image

I repeated my method of lining the cockpit and seat with cling film, squeezed the bottom with putty and then sat the driver in, this will create a mould for the driver's back in the actual position that the seat will be in in the finished model, I then put the engine cover back over to make sure his head was correctly positioned.
Image
Image
Image
Image
Image
Image

And that's it for today, I'm still confident of getting the driver finished next weekend.

Cheers,

Alex

ajdavison2
ajdavison2
32
Joined: Wed Dec 08, 2010 11:41 am

Re: 1:8 McLaren Honda MP4/4

Post

Hi everyone, been a minute but I'm back with another update. It's taken significantly longer than I wanted to get the driver right, mainly due to putty curing and I've been working away Monday to Friday so recently I've only been able to do some work at weekends, and been busy with other stuff etc etc.

Anyway, so last time I posted I had moulded the torso of the driver to the seat with putty and cling film. One of the reasons gaps between updates are so long are that I'll set the model in the putty, and it'll have to cure overnight, so I can only really do 2 stages per weekend.

Here's the driver torso moulded and cured, and removed from the plastic:
Image
Image
Image
Image

And test fitted in the cockpit with the leg pieces:
Image
Image
Image

Cling film and putty in the seat for the leg pieces:
Image

Leg pieces placed into the putty to mould and cure:
Image

And removed from the cling film post curing:
Image
Image
Image

Dry fitted to the cockpit after curing:
Image
Image

Next I had to carefully remove the thumbs from the hands, this was done so that the model could be removed with or without the steering wheel. I did it with a craft knife instead of a saw to keep them intact, before shot:
Image

After:
Image

After this I dry test fitted in the cockpit with the steering wheel to check the position of the arms, at this point I found out the driver's left leg was too high, stopping the steering wheel being able to sit fully flush, you can see what I mean below:
Image

So I shaved this part of the leg off (to be filled later) and re-tested the fit with the arms, this time the steering wheel sat as it was meant to so happy days:
Image
Image

When I was happy with this I cling-filmed the cockpit and attached the arms with putty:
Image
Image
Image

And a close up shot of the steering wheel sitting in the, as of yet, thumbless hands haha:
Image
Image

Model removed from mould after curing:
Image
Image
Image
Image
Image

After this the thumbs were glued back on. I appreciate that this isn't how the wheel will be held but I decided it's the best compromise between accuracy and the flexibility of being able to remove the driver if I want to.
Image
Image

Test fitted with the steering wheel:
Image
Image

Test fitted to the cockpit with the steering wheel, you'll notice some damage to the cockpit next to the shoulder areas, I must of pushed the putty through the clingfilm by accident and it ended up slightly deforming the ABS plastic that the cockpit is made from. Annoying but I'll touch it up with some black paint as best I can:
Image
Image
Image

Shoulders, leg, thumbs and other parts filled with putty:
Image
Image
Image
Image

Test fitted to the cockpit again:
Image
Image

And with the seatbelts in place:
Image
Image

And engine cover:
Image
Image

After I was happy with this I went through a few stages of rubbing down with sand paper and re-filling any gaps:
Image
Image
Image

Chose not to sand the back down as it's moulded to the seat, so I didn't want to risk making this not fit anymore:
Image
Image

And my set up for priming layer 1:
Image

After priming layer 1, rub down and re-fill:
Image
Image
Image

After priming layer 3:
Image
Image
Image
Image

And that's it for today everyone, as we speak it's currently got the final priming layer on which I'll rub down and then I'll get started on the red which I'll include in next weeks update.

Thanks for reading as usual,

Alex.

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

Re: 1:8 McLaren Honda MP4/4

Post

Driver turned out much nicer than it looked like it was going to in some of the pictures.
Very fiddly but you really hit a home run in the end. :wink:
Once again have to compliment you on your perseverance.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss