Bentley 4 1/2 litre Blower in 1/12th scale - may contain Airfix.

[modelbautony]

ah, a panel riveter?

[nick]

11 minutes ago, modelbautony said:

ah, a panel riveter?

Close but no banana

 

all will be revealed tomorrow 

 

Nick

[Malc2]

Chequer plate?

[CrazyCrank]

A jig to help spacing regularly the swirls to get an engine-turned panel (guilloché-work) ?

The teeth on the border of the superior and inferior plates would help to get a regular offset ?

 

[nick]

7 hours ago, CrazyCrank said:

A jig to help spacing regularly the swirls to get an engine-turned panel (guilloché-work) ?

The teeth on the border of the superior and inferior plates would help to get a regular offset ?

 

We have a winner! Yes exactly.
 

It’s for the engine turned instrument panel. I have tried drawing and 3D printing these patterns, but even when they are at the maximum resolution the printer is capable of, they aren’t subtle enough as you can see on this test Piece. 
 

 

Nick

[CrazyCrank]

1 hour ago, nick said:

We have a winner! Yes exactly.
 

It’s for the engine turned instrument panel. I have tried drawing and 3D printing these patterns, but even when they are at the maximum resolution the printer is capable of, they aren’t subtle enough as you can see on this test Piece. 
 

 

Nick

 

This jig is a fabulous tool. I pick this idea for my future builds

Could you tell us which kind of tool bit you used to engrave the swirls ?

[nick]

1 minute ago, CrazyCrank said:

 

This jig is a fabulous tool. I pick this idea for my future builds

Could you tell us which kind of tool bit you used to engrave the swirls ?

Yes that’s the problem right there.
 

After much googling, a material called ‘cratex’ is the answer. If you’re old enough to remember old style ink erasers, it’s a very gritty rubber-ish compound, it’s like that. 
 

I found something similar for dremel, which is pointed, so you need to cut the point off. 
 

you also need rubbing compound, like valve grinding paste, or even toothpaste. 
 

watch this space!

 

Nick

[CrazyCrank]

9 minutes ago, nick said:

Yes that’s the problem right there.
 

After much googling, a material called ‘cratex’ is the answer. If you’re old enough to remember old style ink erasers, it’s a very gritty rubber-ish compound, it’s like that. 
 

I found something similar for dremel, which is pointed, so you need to cut the point off. 
 

you also need rubbing compound, like valve grinding paste, or even toothpaste. 
 

watch this space!

 

Nick

 

Thanks for sharing, Nick

I've found a reseller in France, but he sells only big sets of tips / disks and the price is insane !

Which reseller did you deal with ?

[s.e.charles]

can "almond paste" be used as a compound substitute?

 

i have a surplus i'm trying to use up.

[CrazyCrank]

1 hour ago, s.e.charles said:

can "almond paste" be used as a compound substitute?

 

i have a surplus i'm trying to use up.

 Yes, of course !

Personaly, I use it to lubricate my esophagus 😉

[nick]

While the DFV is printing, I thought I would wake the old Bentley up.  The engine is mostly done, but a corrected engine doesn't fit the Airfix made-up radiator. At which point I took a break, as I didn't fancy tackling the radiator shell.

 

Here's why:-

 

 

A couple of things there, the badge is quite complex, and although there are vector drawings of the Bentley logo, they are the modern, slightly cleaner looking version, not this vintage one. So anyway, I ended up drawing it from scratch in illustrator.

 

The next thing is, it ain't flat. Not just bent in the middle, but curved, like this:-

 

 

Whilst fusion 360 does have an emboss function for this purpose, I can never get it to work on complex, compound curved surfaces like this. Of course this was no exception, so much jiggery-pokery was required.

 

Finally, I had to figure out and draw the mesh from scratch. the standard meshes are all 2D ie a flat surface with round or square holes punched in it which I didn't like. this is about right I think for the style Bentley used with alternating bends at each junction.

 

Thanks for lookin,

 

Nick

 

[Noel Smith]

Nick it is almost there. I put a picture up on the Scale Motorcars website to refer to in your thread.

I was reading what you said about the compound curve on the top of the radiator shell being  very difficult to draw the badge on it in situ. Maybe supplying the badge as a separate item might be an option to place on the curve of a blank radiator shell instead. A small flattish item like that would have a little flexibility for the modeller to be able to place it with adhesive.

I have some more pics of UR6571. Please message me with your Email and I can get them off to you if you think they may be of further help in your endeavour.

Cheers  Noel

[Quiet Mike]

Wow, this thread is amazing, what a build! I am currently learning a 3D program called Blender at work, for Arch Vis stuff. It's mind boggingly complicated for a luddite like me to get my head around, I much prefer doodling in Illustrator! I imagine Fusion 360 is the same.

 

Your radiator prompted me to post a snap I took at the recent Goodwood Members Meeting, I'm not sure it's a help or hinderance! But Bentleys were out in force on the track.

 

Bentley by Mike, on Flickr

[Nick Belbin]

This is just mind-blowing!!

[bigbadbadge]

Just caught up and the engine looks beautiful,  just need a fuel supply and it will run like a dream.  

Really awesome work 

Chris

[albergman]

Just read through this latest project and enjoy watching you solve problems.   I want to test my memory of Fusion and ask if this would have worked for that beautiful, brass, "bent" Bentley badge.   How's that for alliteration?

 

If you had drawn the BBBBB extra thick and flat could you have extruded the correct bonnet curve through it ... once above and once below to trim it to the desired thickness and curvature?

 

Frank

[Pouln]

On 12/20/2021 at 5:50 PM, nick said:

While the DFV is printing, I thought I would wake the old Bentley up.  The engine is mostly done, but a corrected engine doesn't fit the Airfix made-up radiator. At which point I took a break, as I didn't fancy tackling the radiator shell.

 

Here's why:-

 

 

A couple of things there, the badge is quite complex, and although there are vector drawings of the Bentley logo, they are the modern, slightly cleaner looking version, not this vintage one. So anyway, I ended up drawing it from scratch in illustrator.

 

The next thing is, it ain't flat. Not just bent in the middle, but curved, like this:-

 

 

Whilst fusion 360 does have an emboss function for this purpose, I can never get it to work on complex, compound curved surfaces like this. Of course this was no exception, so much jiggery-pokery was required.

 

Finally, I had to figure out and draw the mesh from scratch. the standard meshes are all 2D ie a flat surface with round or square holes punched in it which I didn't like. this is about right I think for the style Bentley used with alternating bends at each junction.

 

Thanks for lookin,

 

Nick

 

Hi Nick, looks really good. I was facing the same with the Alfa knock-offs. What I dis was the following. I increased the height of the logo and then used the surface (in your case of the radiator shell, to make a cut (subtract the shell from the logo). That way you have a upper surface that is perfectly following the flow of the shell. I then pulled up the logo such that it sticks out of the shell sufficiently. If necessary you can o the same with the underside of the logo if it sticks too far into the radiator shell. 

[nick]

27 minutes ago, Pouln said:

Hi Nick, looks really good. I was facing the same with the Alfa knock-offs. What I dis was the following. I increased the height of the logo and then used the surface (in your case of the radiator shell, to make a cut (subtract the shell from the logo). That way you have a upper surface that is perfectly following the flow of the shell. I then pulled up the logo such that it sticks out of the shell sufficiently. If necessary you can o the same with the underside of the logo if it sticks too far into the radiator shell. 

Yes I did that twice in effect. once for the 'background' of the badge so that surface tracked the base shape, then I extruded the raised portion of the badge over the top of that and cut with a slightly enlarge version of the shell again.

 

Regards,

 

Nick

[Noel Smith]

Going back a few posts about making the engine turned finish on flat aluminium for the dashboard.

 

I have found that a very small end milling tool but to be the best item for this. They are generally available from engineers suppliers in different diameters. But be aware that the standard shank size to be held in a chuck on these cutters is 6 mm diameter.

 

Alternatively if you only have a small modelling power tool like a Dremel with a small chuck that will only take smaller diameter drill bits, you could grind the end of a drill bit flat to simulate a small milling cutter. The power tool really needs to be mounted in a holder so that you can use it like a bench drilling machine for better control.

 

Nick's jig for 'stepping' along the horizontal axis to equally place the swirls would work fine with the above.

Edited December 25, 2021 by Noel Smith

[nick]

23 minutes ago, Noel Smith said:

Going back a few posts about making the engine turned finish on flat aluminium for the dashboard.

 

I have found that a very small end milling tool but to be the best item for this. They are generally available from engineers suppliers in different diameters. But be aware that the standard shank size to be held in a chuck on these cutters is 6 mm diameter.

 

Alternatively if you only have a small modelling power tool like a Dremel with a small chuck that will only take smaller diameter drill bits, you could grind the end of a drill bit flat to simulate a small milling cutter. The power tool really needs to be mounted in a holder so that you can use it like a bench drilling machine for better control.

 

Nick's jig for 'stepping' along the horizontal axis to equally place the swirls would work fine with the above.

Thanks for the tip, I assumed that would be a bit too severe? But I’ll give it a go. I have a full-sized drill press so the shank shouldn’t be a problem. Chronos have got a nice little set of endmills that goes down to 1/16th so that should work. 
 

Nick

[Noel Smith]

Nick, it is just a matter of getting a 'feel' for how much pressure to use with a small end mill in a drill press. A bit of practice on some oddments of aluminium sheet will quickly give you the idea. Using that type of tool might on the face of it seem to be a fierce option, but it does work ok.

 

I like your ingenious jig design for equi spacing the swirl patterns that can be screwed down onto a short bit of batten.

Hope you get on ok with the cutters.

Noel

Edited December 26, 2021 by Noel Smith

[Jo NZ]

I started playing with the turned finish on the Brooklands car - then discovered that the dash wasn't engine turned! I used a mill (2mm?) at a fast feed speed and got the result below. I was intending to sand it down to dull the pattern a little, but never did it.

 

 

[nick]

13 hours ago, Noel Smith said:

Nick, it is just a matter of getting a 'feel' for how much pressure to use with a small end mill in a drill press. A bit of practice on some oddments of aluminium sheet will quickly give you the idea. Using that type of tool might on the face of it seem to be a fierce option, but it does work ok.

 

I like your ingenious jig design for equi spacing the swirl patterns that can be screwed down onto a short bit of batten.

Hope you get on ok with the cutters.

Noel

Placed an order with chronos now, so will let you know. The jig works well in fairness, the tips I was using, not so much, so didn’t post any images. 
 

Nick

[Brandy]

I bought a drill press to use with a dremel and a dentist bit to see if I can get the engine turning effect, but the proof of concept is a long way off yet.

I do think your radiator top is too flat though, it needs to have more of a slope from front to back. The badge is not flat on top as shown by @Quiet Mike's pic

 

Ian

 

 

[CrazyCrank]

To give the T50 Bugatti's firewall and engine side plates an engine turning effect, I used ages ago the drill press tool of a UNIMAT 1 (a toy in reality), and a 6 mm diameter rotating wire brush, whose wires had been previously surrounded by a copper cable, to prevent them from spreading during rotation, which would have increased the diameter of the tool and compromised the regularity of the result.

 

On the picture below, the brush wires are free, and after the first attempt, I wrapped them

 

  

 

  

 

As Noel Smith said, to engrave smaller swirls at your 1:12 scale, you could use an 3 mm diameter end mill and practice to develop dexterity.