Imo000

Covering the shifter **** is a real PITA. This might be a good opportunity to redesign the top end to make the leather easier to form.

Jerry Feather

Great! It's going to be interesting to see what you come up with.

Imo000

No hidden agenda, just trying to save you some headache.

Jerry Feather

If you don't show me your design idea how does it save me anything?

Tom in Austin

Neat project Jerry. What ever happened to the manifold?

Jerry Feather

Hi Tom. The Manifold is still in progress. I have not yet decided just how to proceed with all the welding that it is going to need. This project tends to take precedence since I have an obligation to a couple of others regarding the Shift *****, but only to myself regarding the manifold.

Jerry Feather

I had expected that at least two of the 100 ml syringes would be here before this weekend, but not. Maybe they will be in today's mail. If not, maybe I can find one or two locally so I can get the molds drilled with the injection port and vents and try to form a couple ***** this weekend.

The other thing I can do is some forming of the **** top leather forms which I have started by glueing together some aluminum plate and wood blocks for the basic body of these. I have those pretty well figured out and can start doing some milling and carving on them using the original ***** for the forming.

Jerry Feather

I think that the reason the leather covering of these shift ***** is seen as a "PITA" is because of the shape of the top of the **** and the fact that leather only comes flat. Although the fact that cow hide doesn't grow flat to start with starts to tell you something that becomes useful in accomplishing what someone did for the Porsche Factory with these shifters as produced.

I started this project by taking the leather off of two or three ***** by cutting the seams front and back and then soaking the leather in warm water for a while to saturate it, then I pressed the pieces flat between sheets of newspaper to flatten it and dry it out so I could see what they started with and so I would have something to use as a pattern.

What I find with the early **** leather is that when the leather turns back to flat, or close to it, there is not quite enough leather to go over the big part of the ****, the actual **** at the top, and of course, there is much too much leather to simply push into the recess on top of the **** where the little plastic shift pattern insert goes. What that means is that the leather had to be stretched over the big part of the **** and then had to be gathered so as to fit into the top recess.

With the Factory **** I think this was accomplished by soaking the leather before it was installed. At least, that is what I plan to do with mine. It is also apparent that with the Factory *****, at least the early ones, the leather was skived in the area that goes over the **** and into the top recess. I think the GTS **** leather was not skived except maybe right at the very top, but not over the big part of the ****. The GTS style of doing this is also what I plan to do with all of them.

When the leather is soaked I think it will fairly easily stretch over the top ****, but the gathering over the very top to make it both smooth and small enough to go into the top recess will be the big trick to perform. Stay tuned to see how I plan to accomplish that.

Jerry Feather

I received two of the syringes yesterday and put one of them to good use this morning. I first drilled the injection ports then cut the other vents in on of the mold that needed it still, then I mixed up some compound. I had quite a time converting all the weights and volumes into what I needed in compound to cast two of the *****. but with a little bit of rounding up I came out with only a small bit left over. I just hope there is enough left of the first pound to cast two more *****, if it works at all.

I waxed the mold pieces inside then painted them with mold release, so hopefully they will come apart tomorrow when the stuff sets.

Here are some pictures of most of the process. I notice that I must have had my hands full doing the actual injecting because I didn't get a picture of that. I finished up putting one of the molds in my mill vise to hold it upright and set the other one next to it, hoping with both of them that the air bubbles I am sure I had in the compound will migrate to the top and out the vents. One picture does show the air that floated the to top in the mixing cup, but I think there was probably more.

I decided that the best way to fill the syringe was to suck the compound out of the mixing cup with the syringe plunger. That seemed to work ok except for the last little bit I needed since the plunger seened to be kind of stuck. I did get it apart later and wiped it off, but I'll let the syringe body set to cure and then see if the compound will peal off of it so I can reuse it. No big deal since I have about 30 more coming from the far east and they are only about a buck fifty or less each from there. The two I got yesterday were twice that from CA.

One picture shows the syringe stuck in the mold pointing down, but when I did the injecting I injected from underneath the mold and slowly so the I wouldn't trap any air with the compound, at least any that was not mixed into the compound. The first mold took just over 60 ml and the second one a bit more than the 100 ml in the syringe. I should have put the last of the first syringe full into the second mold and then filled the syringe again. In fact I had planned to do that, but got ahead of myself in the whole process.

Jerry Feather

So, the big moment finally arrived. I brought the molds in last night to finish curing where it is a bit warmer, then I opened them up while my coffee was brewing this morning. There is some high degree of success, but a bit of failure also. The GTS **** formed nicely, but there is a large bubble in the small end of it. Its nicely formed around the bubble and maybe I can inject it later with some compound, but even without that it will finish out just about exactly like the original since the bubble is just about equal to the amount that I added to the bottom in the new design of the ****.


Both ***** are still partly stuck in half of the molds so I'm going to have to wait until I can take them out the the shop and clamp the shafts in my mill vise and pull them the rest of the way out of the molds. Then the trick is going to be to see if I can pull the shafts out of the newly formed *****.

Here are the pictures.

Jerry Feather

I went ahead and forced the GTS **** out and here is what it looks like , but still with the two metal mold components stuck in it. The whitish stuff all over it is the mold release.

And here is the shift pattern insert recess with its mold removed.

Jerry Feather

You can see in one of the pictures that the rubber in the GTS **** has pulled the top off of a small bubble in it's mold. I'm going to have to patch that and finish it before making another **** with it.

There is a little bit of bubbling at the small end of the early **** also, but that will best be ground off. I'll keep working with the process to try to eliminate the bubbles. Maybe I'll make the small air vents a little larger so the air has a better chance to escape. The vents can be quite a bit larger since they will just get cut off in the end.

Rob Edwards

Are the bubbles from flow voids during the pour, or might there be a benefit to de-gassing the compound pre-pour? Perhaps that's not done for these rubber compounds, but it seems to be important for 2-part epoxy compounds.

Jerry Feather

Rob, I let the compound sit for a while after I mixed it to have the bubbles rise, but they do not want to break at the surface because of the surface tension of the compound. Then I sucked the compound out of the mixing cup with the syringe, but from under where I thought the bubbles were at the surface. The compound has a 30 minute pot life, so maybe I need to wait a bit longer next time.

The large bubble in the GTS **** I think was put there with a bubble in the syringe that was created in the suction process. I remember feeling and hearing a large bubble get injected. I'll try to do something different next time to eliminate any larger bubbles in the syringe - - maybe holding it upright for a while to have the air rise to the outlet end then push it out before injecting into the mold.

Jerry Feather

Both ready for the last test - - to see if I can pull the shaft out of them.