Soft Top

[07cob]

All

Well, it has taken longer than building my car in the first place, but I am finally ready to get the Soft Top made. Here are some progress photos of the frame and a mock up with a sheet to check the overall shape. The canvas will be quite a lot heavier than the sheet so hopefully won't have such sharp corners - something I am trying to avoid.

I am not 100% sure about the height - I will do another mock up later today and might lower the rear and centre bows a little.

Bend in Al channel for header bow


Frame


Mock ups




Cheers

Geof

[Zedn]

Looks great,

How did you bend the channel?

[sambo]

Looks good Geof. What are the bows made from and how do you get the nice bends/radii?

[07cob]

Originally Posted by Zedn

How did you bend the channel?

Liam

I made up a bending jig as shown in the photo below. It is a bit agricultural but it does the trick. The Al was annealed then it is as simple as rolling it around the corner (with a degree of brute force and ignorance). There is some distortion but no cracking. I just filed down the excess material to give a reasonable finish.

Originally Posted by sambo

What are the bows made from and how do you get the nice bends/radii?

Paul

Bows are just 10mm mild steel. I started this as a *prototype* with the intention of going to stainless once complete. Given that it took so long to get this far, I reckon I will be happy with this for a while now. All the radii are bent by hand and eye. Once I cut the bows in half, I adjusted them to ensure some degree of symmetry.

Cheers

Geof

[renovationinnov]

just got to love a ""rag top "" all puns intended
top job , nice jig for radial bends keep us posted

[Merv and Sharon]

Neat jig Geof! I am sure that you went through this earlier thread Hoods and Tonneau covers

The shape of the top is a tricky thing. I did not want a pronounced bend up in the middle



To do so I had to reduce the height of my roll bar (it was far too high anyway) and play around with the height of the bows a bit. I also wanted a bit of a slope at the back. The old sheet trick is a good way to test the options out!

[Rog246]

Err so Geof, when are you taking orders for these ?

Rog

[07cob]

Merv

Originally Posted by Merv and Sharon

I did not want a pronounced bend up in the middle

This is actually one of the things I was trying to achieve. I want the top to resemble the shape of a hardtop with the curve up off the screen then curve all the way back to the deck. I still reckon I could come down a bit - I will have to test this out later - didn't get a chance today.

Originally Posted by Merv and Sharon

I also wanted a bit of a slope at the back.

I agree! So much so in fact, I considered taking the top back over the boot to create a Le Mans style soft top with zippers beside the boot for access. Not quite brave enough to give that a go though.

Cheers

Geof

[07cob]

Originally Posted by Rog246

Err so Geof, when are you taking orders for these ?
Rog

Rog

It took me almost two years to get this far, .......

Geof

[Merv and Sharon]

I am ALMOST ready to do the hard top with Steve, for the Harrison. The mould is now ready I believe. It is fairly flat too. I think we had some photos earlier on it.

I found that with the soft top I used it more in summer for heat (in QLD), whereas the rain, well it just came in the sides. Wind flap was not a problem with the shape I have. Fitting windows to the soft top is hard and resembles the old MGA/clubman design. The hardtop can take a fixed window.

[jcraigau]

I was thinking of getting a second set of doors done with glass in them for winter time.

This came about after the wife won't ride around in her MX5 without the windows up (something about the hair?). Roof off is no problem.

Not sure about having them workable with winders or just set in place with a slider assembly.

[Rog246]

Originally Posted by 07cob

Rog

It took me almost two years to get this far, .......

Geof

So ...............ypu're taking order well in advance then !?!
Rog

[Outwest34au]

Good stuff, the shape does look good.

For those that missed it here is a good article on bending channel with view to making window frames. Home-made Side Curtains for Lemans Top – “How To”.

[Merv and Sharon]

Very good article. Have filed that one away!

[07cob]

Originally Posted by Outwest34au

For those that missed it here is a good article on bending channel with view to making window frames. Home-made Side Curtains for Lemans Top – “How To”.

Great tips in this write up. The Lotus site quoted (LocostUSA.com • View topic - Trouble Bending Aluminum for Windshield. Help) is where I got the idea for the jig.

The tip about using a Sharpie as a temperature indicator for annealing is also a good one.

I used soap for this. Rub the soap on the top three faces of the channel the heat from below. I used a LPG torch. The soap will turn brown then black. Afther that the aluminium will start to melt - not good!! Same as the sharpie method - stop heating as the soap goes black. This is the discoloration on the channel that can be seen in the photo above.

Colour chaning crayons can also be used if a more exact temperature is required.

The only downside to this is that unlike other metals, there is apparently no way to re harden the aluminium. It will work harden as aluminium does, but otherwise it will remain *soft*. Whether this is a problem will depend on the application. Probably not much good for an alternator bracket but fine for a cover panel.

Cheers

Geof

[07cob]

Done and Stoked

Thinking the top (as per photo above) might be a little too high, I adjusted the bows and ended up with the following for a mock up:



So then off to the trimmers and after picking up the car ... I am very happy with the result:






It is amazingly different to drive. I can talk to the passenger without shouting and there is just no breeze. More like a car than a Cobra! Will just have to wait and see how it handles nasty weather.

Geof

[Merv and Sharon]

Very good Geof! Nice profile and that just might help the rain keep away. Now for the engine?

[Krait]

Well done Geof. Looks fantastic.

Cheers

[guye]

Nice job, Geof.