The challenge is not the legs but the top plate of the tripod. It is made of sand cast iron. I needed to find one to get measurements and to then enter it's dimensions as a 3d model so it could be made on a CNC machine.

My friend Dan had the plate and was cheerfully able to supply me with dimensions. Click on a thumbnail for a larger picture.

 

The dimensions went into a 3D cad program and generated a 3d model of the plate. Here is a video of what that produced.

 

My brother is the owner of TXS Design an industrial design firm in Dallas texas. He also happens to own a company that has 4 computerized CNC machines. He converted the 3d model into code for the CNC machine and produced a plastic model. The plastic model then was sent to me to see if it fit the mount properly. It did

 

With the success we had with the plastic model, it was time to produce the model in aluminum. Two aluminum blocks were purchased and we ran off two pieces. Each took 6.5 hours to run with two changes in the CNC chuck.

They came out quite nice and both were painted to match the mount.

 

So success you say? Well, the models are perfect. Too perfect. And they do not weigh anything like the real thing that was produced in iron. If you go back and look at the original part that Dan measured for me, you will see lots of rough line. Those were made by the wood block that was used to make the impression in the sand. As the blocks got used more and more, the blocks got rougher and rougher. I recently had a chance to view another plat and it is not as rough. But it still had the "wood grain" images in the steel.

So where do we go from here. To a foundry.

 

ART Research foundry just happens to be owned by my brother business partner's Mom. They are known for their work with sculptures and in fact, took part in the "Alice in wonderland" statue in Central park NY. I contacted them and I am currently working with Tracy, and estimator for them.

http://www.thinksculpture.com/index.asp

My objective is to produce 9 or 10 copies of the plate. Many collectors around the country are very interested in this process and in the final product. More than half of all Clark are missing their tripods. Many collectors have their telescopes sitting on a shelf in their living room or study. I hope to change that. Not for profit, but because I can offer those collectors something that they could never realize.

So why not use the CNC copies? They do look very good even if they are too perfect. They are just not cost effective. One run on the CNC machine would cost between $650-850 and that would not include the $1500 setup charge. I know many a collector that would probably pay that, but why not have something closer to the real thing offered at a more reasonable price. Sand casting can produce a plate for much less. How much less remains to be seen. Keep in touch.

If I can work out the details (and the cost) I will take you on a trip to the foundry to follow the process. We will be using stainless steel for the plate. It was explained to me that the "cast iron" process is dirty and causes way too much smoke. The EPA has pretty much shut down the foundries using this process unless they install expensive smoke scrubbing equipment.

Stay tuned, I will keep you informed

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This is the tripod I am trying to re-create. I was lucky to find a friend who had one. This is from 1919 (close enough) and will do quite well for my model.

 

The leg restraints are very simple on this Clark. Belts!

 

I just finished a phone call with Tracey at ART Research foundry and we discussed the process and some of the costs involved. It looks like the part will cost a little less than 1/2 the CNC price. That price will go down if I make more. I will be contacting a few collectors to see if they will help by purchasing a plate off me. As I said earlier, maybe I could also offer the entire tripod (include legs and hardware).

I will be sending the CNC part to them today for them to look at. I will be traveling to that area of the country (Lancaster, PA) on the 17th and I will meet with Tracy and the owner to discuss the project further. That said, I don't know what the setup cost is nor the cost to machine the top ring. These things also will enter into the cost of the project. I just hope it works out and I have enough collectors of Clark willing to invest in the project. I will be going out to California for the Vintage Telescope Society convention in San Jose. Maybe I will be able to convince a few to participate.