Lola SL142/20 Restoration

[Rhino]

Looking at your nickel/bronze brazing Reto. Are you using a jet flux mix in the acetylene?

[Reto Kuprecht]

No Rhino, at this time I am practising with uncoated and coated Nr. 18 rod from Castolin Euteuctic, but always using their flux to prepare the metal. What I can already say is that the joints you see on the pic are extremely strong. It seems to me that if one follows the main rules, a very strong joint can be achieved. And the cosmetic side follows with training. I am slowly getting the idea of really making a bead, and not just letting the filler get to thin and flow away. But even then, the joint will be very strong. I will continue practising on scrap pieces until I have reached an acceptable standard before I start brazing on the Lola. If you have any hints or tips on this - please let me know

[Rhino]

I could tell by how "DIRTY" the metal looked that you were using a paste flux Reto.
I am no expert in the fact of nickel brazing: however, I have had a little better luck at it.

The first thing I can suggest is to use a JET flux. Jet flux is in a liquid state and is held in line with the acetylene. As the acetylene passes (bubbles) through the flux, the flux is mixed into the acetylene. You can purchase this flux by the gallon and the flux mixing bottle at any reputable welding supply shop. It will give your flame a green color. You should use a blue tinted glass to view through when using this flux. The benefits to using Jet flux is that you will be able to use non coated Nickel Bronze rod, keep a clean area to work with for better visibility and is easy to clean (just wash off with a wet rag).

My second suggestion is to use a OOO tip or better yet a jewelers tip when brazing. You want to have a very hot but small flame. Only heating the mating surfaces to be brazed and not the entire piece. Do not get the metal red hot or the braze will boil. I always set my acetylene to a max of 5PSI. This will be more than enough to do any job.

Finally, If you haven't heard enough Reto, I always spend the majority of my time brazing trying to get the braze to just adhere to the metal. Once I have achieved this then the rest of the braze is literally spot brazing. I let the braze cool enough to harden, then start again next to the last braze. Overlapping each spot braze to get the welded bead look.

I hope this helps. It is only one man's opinion. Good luck to your ventures Reto.

[Reto Kuprecht]

This are extremely helpful comments. I knew about the jet flux, but didn't really about its advantages. And your tips about concentrating the heat just enough to create a bead is exactly what I have been starting to find out myself during practising. Unfortunately the people who showed me how to "braze" did brazing and not braze welding and I didn't really get the idea there. I'll go and buy a smaller tip and will continue along the lines you are describing. I assume you agree that braze welding is a interesting and very effective process (there are still people I talk to who say I should stop glueing metal together )
Thanks again, Reto

[Rhino]

Reto,
I know what you mean when it comes to Gluing metal together. I do still get un-nerved with using braze: however, it does have its benefits.

I use braze when I need apart to "flex" and won't have severe circumstances if it were to fail (such as brackets, pedals and water plumbing). If I need to make up some suspension pieces, were rigidity is a plus, I still go with TIG 70-6 .045" rod. Minding the temperatures of coarse.

It is also a good thing to know if you ever have to do repairs to a chassis that was originally built with "The glue technique"

Cheers,
Reinhold

[Jerry B.]

I find that using a # 2 or even a number 3 tip works well but that is on .065 to about .095" wall tube and with thin sheet go down in the tip size accordingly.
I would not use cobalt blue goggles because of eye health issues with constant use but also they are very expensive and hard to find.
A number 4 or 5 green glass in a welding hood so as to deflect the smoke/gasses and at least a good 3M dust mask that will filter the smoke be used.
Build a gas fluxer ...take a look at gasflux.com and get ideas. You will be using liquid flux and bubble the Acetelene gas thru the flux and they combine in the hose and the torch with a green flame. You want to use a valve to bypass the gas fluxer to set your heat flame to neutral and to preheat the work then turn the valve and you will get flux in a minute or less. Here in the Colonies we can buy the liquid flux but not the correct composition rod. I will have to check my notes but we only have availiable 6 or 7% nickel while the original was 9% and there is omitted some strategic other chemicals with the 7% rod. The "good rod" is still availiable in the UK...do a computer search. There might be a incompatibiliy in repair or rework using 7% rod on 9% rod. It is definitely a different color tint which does not matter but the incompatibility might.
And yes...clean parts are a must. Use some 400 or so paper to final clean parts. With years of practice you might get looking like you worked at Arch motors....very strong weld joints and keeping low temp on the metal being joined are the benefits.

[Reto Kuprecht]

Very encouraging, Reinhold and Jerry - thanks for the insights! And I love the term "the Colonies" but that's off topic

[Reto Kuprecht]

The original T142 dashboard had five gauges, a chronometric Smiths tach in the middle, and four gauges clustered around it for temps and pressures. To keep things as simple as possible, I decided to limit myself to the tach, a combined oil/water temp gauge and an oil pressure gauge. Here is the new panel for these instruments and the necessary switches:

Original mechanical Smith tach, restored by www.nisonger.com:


Rubber anti-vibration mounts:

[Reto Kuprecht]

I tried out the new panel sitting in the car, steering wheel installed, and noticed that I couldn't see the two smaller instruments - so I made a new one. Should have done the testing before
The tach cable is attached too and the oil pressure line. I know where the oil temp sensor will go, but still contemplate where I want to place the water temp sensor.



Here's the oil tem sensor in the oil pan, with the correct AN-BSP adapter:



All the hard lines are done too, including their attachments. I choose to bronze braze steel rivet nuts to the chassis tubes for the clamps instead of drilling holes into the tubes:



Bulkhead fitting splits main line to both rear brakes:

[Reto Kuprecht]

The original battery location was behind the seat. However, with the planned fuel pump and header tank there's no space there anymore, and I also wanted to shift more weight to the front. We therefore mounted the battery just in front of/partly under the seat. The attachment allows to put in a larger battery if necessary:



With the battery done, I started to think about the fuel tanks. The original ones were bladder cells, running all along both sides, without protection. As I am not going to use the car in a regulated race series, I will make smaller, welded aluminum tanks. I'll start with cardboard mock-ups and templates - and then we'll see whether master welder Rolf Kopinits can do his magic again and transform this into functional and beautiful pieces:

[Reto Kuprecht]

The nose box is pretty much finished now, with the two aluminum access covers to block the drivers compartment from hot radiator air:



With the radiator installed we have a compact and rigid unit now. The question is: With less open space behind the radiator now, will there be enough airflow on the "out" side, left and right behind the radiator? Or should I make openings in the top of the nose piece to create more air outflow - I'll have to try it out.

[Reto Kuprecht]

Thoughts on strong engines

When I look at this tube frame chasis and think about the 500HP V8 and massive torque behind the seat, the thing seems ridiculously overpowered. But the fact is, you can never have enough

As I had commissioned my engine to Hekimian Racing Engines in Boston "HRE", www.hekimianracing.com, I was also very interested to hear that NZ F-5000 winner Ken Smith is using one of Gregg Hekimians motors in his Lola T430.

http://www.sportscardigest.com/nz-f5000 ... am-trophy/

The HRE Engine in my car ran close to 500 HP on a stationary dyno. However, my engine being handicapped by several special "requests" of mine, such as an old style magneto ignition and certain savings on more sophisticated parts, I can only wonder how strong Ken's purpose built engine must be. And I also heard that it was "only" run to 7600rpm, and could do more...

I am. of course, not saying at all that Ken only wins because of this engine, however - as I said - lots of power does help

[Reto Kuprecht]

It took quite a while for my master welder to tack weld the fuel cells main panels. But the result looks encouraging, no wide gaps yet and not too much distortion. And the inner panel still fits with the attachment points on the car. Here's a first test fitting. On top the marking where the filler tube will go:



And another view of the RH cell on the bench with that same hole cut already:



A view from the inside, with the access hole, reinforcing ring welded to the inside with threads cut for the 10-32 screws. In the rear bottom corner a -10 weld bung for the fuel outlet. This and the other one in the LH cell feed to a header tank through one-way valves. The "serrations" on the top edge of the panel are cutouts to clear weld beads on the chassis.



Detail of access plate. I found out that drilling 16 accurately spaced holes on the drill press isnt't that easy at all And we will cut sealing rings from 2mm sheets of gas resistant NBR compound.



The header tank in loose pieces yet, with a -6 vent on the top, leading back into one cell, and the -10 outlet to the fuel pump. The valved inlets from both cells on the sides will be done when the cells are definitely in place:

[Reto Kuprecht]

We continued fabricating all the parts for the fuel cells. The holes for the weld bungs, vent valves, fuel pick-ups, fuel filler, fuel sensor mounting and front and back sides. Here are pictures of the sensor mount, including a shroud protecting the sensor from touching the safety foam later:





Something I always wanted to try out was a method I found on the internet to take off anodyzing from aluminum parts. Why one would do that is another issue of course - in my opinion only for aesthetic reasons, as one gives away the protective and surface hardening properties of anodyzing. But sometimes the color just doesn't match with the project at hand. So, on our last USA trip I bought the product in question: Greased Lightning household cleaner and hauled it home (through security with no problems ). My first project would be the tank vent valves on which the outside part should be plain aluminum:



Greased Lightning into our nice espresso cups and the valves and - to my surprise - the liquid really starts to act on the parts :



I let it work for a few hours, checking in between....



And, Abracadabra, the anodyzing is gone, the aluminum not affected, cleaned it, buffed it and finito! Thin, worse anodyizing goes off quickly, in an hour or two, better quality or thicker anodyzing can take a few hours. I don't know exactly how this works, I guess it must be caustic soda in the cleaner which does that. I only wonder what would hapen if you clean your super dooper Poggenpohl aluminum kitchen with this

[Reto Kuprecht]

An early christmas present: The tanks are welded and ready to be installed. All the parts we made did fit well and master welder Rolf did a great job once more:



Right hand tank installed with filler neck and vent:



Left side tank with vent line, fuel pump by-pass return line, header tank vent line and the fuel sensor:



The header tank set up is taking shape now and it seems that it is going to work out as I had planned. Can't wait to fabricate the various lines and connect all elements:



While waiting for the tanks to be welded I finished the instrument panel. I opted for a very utilitarian look and did the lettering with the old DYMO embossing tapes:



I have done slightly more complex panels before such as this one, where I could really go crazy with engraved lettering, placards, colour coding and wiring with no end. So the Lola panel is kind of manageable