Lotus 23 recreation built

[Michel]

Hi mates
Some year ago a few members knowing I was starting with help of my grandsons ( after the 907/8 replica built) a project of this tiny and smart 2 seater and they where
advising me to start a thread to show all the process of this built from CAD drawing to completion of the rolling chassis
I had the big opportunity to have access to roughts 2d drawings( and also tons of dimensions of the real deal !!) and had in hand a complete bodywork to repare so access to do accurate molds
At the time I was too busy to document such a thread ; am now cool and plenty of time to do so if you good members are interested to follow such a"tale"
As I have done hundred pics during the built and many Jpeg views of the CAD engineering process

Just a"teasing pic" to show how the project started from arought internet drawing !!!

So any interest in reading such built ?????????????

 

[Jasper]

Yeah go for it, lovely racecar that, and it looks like your starting with the perfect ingredients. Access to the real deal, drawings and a good body!

 

[Ian Anderson]

Definitely it looks like a brilliant project. I only wish I had fabrication skills to do something like that!

Ian

 

[Brian Kissel]

Sounds great Mic. Let the journey begin.

Regards Brian

 

[Neil]

Mic, this sounds like a fun project. In the "Olden Days" the roll bar wasn't so large (none). Here is a picture that I took of my fellow GI, Darryl Lander, sitting in the Lotus 23 of Hawkins/Ryan in the old Nurburgring paddock. Also one of the Ashdown/Johnstone 23. This was the 1962 ADAC 1000 kM race at the 'ring.

 

[Michel]

Yes you are right !! originally they didn't have any and then a small one
And finally when the 23b started to be used on long distance races some had the roll bar I selected
So thanks for your replies mates ; will start the story few by few

 

[Michel]

So this project started because I had the opportunity to help a good friend owner of an 23 b who was concerned about racing with the car with no spares ( suspension and body) so we decided to measure all ( I had no idea to built any at that time )
Once body was molded grandsons where saying ; hey we have done the most important why don't you draw everything and do a project with us
One of them was curious to learn about cuting and welding tubes !!!!
So when help to my friend was over ( and he was happy to be able to race with all improvment and spares we did !!) I started to draw few by few the chassis
Another good opportunity was to meetthe owner of an former UK subcontractor of original chassis ( he had a holiday house there in France not far from me !!) We where talking of this futur built and he offer to dig out some tools and do for us the biggest and more important part of the chassis ; the central bulkhead!!!!!!!!!!!!!!!
So all started from this ( giving the chance to check that all dimensions on the sketches where accurate !!!!!!!!!! And PC work followed

 

[Michel]

few by few tubes are being installed on the CAD chassis ; I tried to trim them one by one in the spirit to have them done by laser !!!!
The roll over bar was also drawn in order to ask a quote to companies doing bending ( very very rare people in France !!! able to accept doing only one or 2 pieces !!!!!!!!!!!!!!!)

 

[Michel]

While the chassis started to be all drawn I started drawing some wood tooling to tackweld the front bulkheads and trying too to draw suspensions parts definition

 

[Jasper]

If you got the time and skill, 3D design and built is the way to go for sure! Nice looking work so far

 

[Michel]

Many thanks mates for your "likes" !!!
So after lot of PC tribulations and hudge amount of hours ( was not used on CAD drawing, am more old fashion "pencil and white paper Man" but watching at young ingineers on the last team race (study office) I worked as Fabrication manager I understood enought by myself how to use those modern tools ......)
I managed to achieve all drawings necessary to start the built with grandsons
In addition doing some internet browsing I had also the big chance to meet more people involved in 23 parts refabrication with some of them( in UK ,US and Belgium) so kind to accept helping me in going forward on this recreation project.................
Those assemby drawings where printed in addition to the one found in the net in order to have a better idea of how to start in scale 1/1 the chassis

 

[John]

Michel would be possible to get a basic chassis drawing off you with measurements on it, it would be interesting to compare to mine and see how close i got to being correct.
regards John

 

[Michel]

starting with the chassis ; I tried to be very close to the original one as it had some of round tubes carrying the engine water cooling ( in period all formula's adopted this process so Chapman used too this on the 23 ) and the square ones carrying oil !!!!
This was done just to match real deal but I was aware that to use the car on modern races will need to do external conduits !!!!
Those specific tubes where welded "apart" and tested in pressure too
Then trimming and tackwelding few by few the all thing .........................

 

[Michel]

Some more tubes going onto the chassis and all bracket being done
With good help of grandsons coming several week ends chassis is coming quite rapidly and they enjoy watching the projectcoming along so fast

 

[Michel]

Thanks again mates for all your likes !!!!!
After 4 good months of trimming and welding the chassis started to be almost done
Thanks to a friend boss of an Kart Cross manufacturing company the roll bar was done in material similar to the ones used on the chassis (25Cd 4s) just alittle softer with possibility of doing nice bends, so was more than happy with that result

 

[Michel]

After checking all suspensions fit and details brackets where ok ( at that point was about a year work) I teached one of my grandson how to use compressor stuff so we started (atfer a good sanding to all tubes and tricky areas) with a cromate coat , then an 3+1 polyurethane primer and 2 days after the final coat of what we found the closiest grey from original chassis using a 2 base polyurétane paint
( I had luckily an old original rear member painted in hand so I had this part "scanned" at the paint shop so they where able to do the exact RAL mix for us !!!!!!!!)
That week was a very sunny august week so when coats where done the chassis was layed outside to cure better than in the shed shadow!!!!!!!!!!!!!!!!!!!!!!!!

 

[Udo Selter]

Geez Michel, that was quick! I suppose it helps when you have a set of drawings. Looks really good.
Regards, Udo.

 

[Michel]

Yes Udo I was lucky to have arolling chassis at home for some monthes so able with kidshlep to pick up tons of pics and all needed measures
then the reverse engineering was done when that car was still home so able to correct few by few the CAD study !!!!!!!!!!!!!!!!! What helped also are the drawings I found on the net and enlarging at a very clever printing shop those to 1/2 scale was also a good help .
So when doing all tubes it was so easy !!!! and as stated what is very handly is that you can have on the same time you tackweld tbes you have laser cut parts on hand to place every single tube on good location
Eventually when you are done with your actual project and want to start anew one I friendly offer you to help you in drawing watever chassis you want to built

 

[Michel]

Once the chassis was in agood status we wanted also to check if the body we had to mold was ok to fit so with all grandsons ( 5 of them !! ) helping with wax and flanges location we started to all molds..................

 

[Udo Selter]

Beautiful work Michel. You obviously know what you are doing.
Regards, Udo.