Jerry Feather

Rob, I would suspect that the Factory, or whoever made the 928 Gas Caps, already has or had a tool or devise that would do this function, probably better than I think mine will.

Jerry Feather

Lately I was able to obtain the longer bolts that I needed to complete the handle for the Separator.

Then, while I was wating on that I set the mill up and started to fabricate some Aluminum Pawls. I am making them out of the 7075 alloy that I mentioned previously being lucky to find in the scrap yard.

I was correct at one point in suggesting that the hard part of the pawls was going to be the hand sawing each pawl blank off of the bar that has been turned into the basic body with flats on each side and teeth milled into one edge of it. The milling of teeth went pretty well, although I went through several of the tiny 1/16th inch mill cutters with the ball end, because they are very easy to break. I found that with the use of a lot of cutting oil they lasted longer, but that made it much more difficult to maintan accuracy in clamping the bars up in the mill vise because of the shavings stuck to everything with the cutting oil.

However, I found some very small taper end mills with the 20 degree per side cutting edges that I think will not be so easy to break and they will be simpler to use to mill the middle groove between the teeth that otherwise takes cutting at two different angles, and several passes to keep from breaking the bits. I'll be trying those in whatever next batch of these pawls I make. They are not ball end, but I don't think that will matter much. It would be nice, but not required.

This first batch is made up of about 14 or 16 four-inch pieces from each of which I can get 6 Pawl blanks. I still have 8 of the pieces to hand cut and mill into the basic blank, so my mill is tied up until I get that done. This alloy of aluminum is pretty tough. It is as hard to cut with this little hack saw as I think mile steel or even carbon steel might be.

What I have to do is cut each piece off of the short milled bar and then mill the exposed end flat and true so I have a true surface on the pawl blank to do the next milling stage.

When I get done with these pawls, I'll be able to finish the three finger tools that will go with these Separators, and then I'll have to do some sanding of all the pieces of the tool and get some of them anodized. I had hoped to have these done by SF 13 also, but that is not looking too likely.

Jerry Feather

While I have been cutting a few of these Pawl blanks off of the milled stock, both as I have time and as I can stand the effort, when I was doing that today, waiting for epoxy to cure on another project, it finally occured to me that this was aluminum and although 7075 T651 is really tough, it is not too tough for my band saw with a bimetal blade in it. So, I finally finished up all the milled stock in short order, cutting each piece off in the band saw and then milling the cut ends true in the mill. Now at least I have it all cut into small blanks and each are milled to the correct height for some finish milling into the locking pawl.

Now I can set up the mill for some finish milling of the three finger tools that I have remade for this project. Then we will see if they work as redesigned. I guess I'll work on that a little later this afternoon.

Jerry Feather

Here is what the devise looks like at this point.

jpitman2

Jerry,
Cutting pawls that way is not fun is it? I made a few by hand myself before I sought out easier ways. I was pretty lucky having indirect access to a tool making wire cutter, and people who could make a digitised plan of the pawl and have a stick of 22 cut in one go. Better still they sliced them up for me as well. Users still need to do some work, but they should last forever - either in mild steel or alloy!
jp 83 Euro S at 55k

brealytrent

That's quite the complex device to separate the gas cap! I doubt porsche ever made such a tool, and just used mini flat bladed screwdrivers to pop it out. At least that's how I did it. Didn't seem difficult enough to warrant creating such an elaborate contraption, if I'm honest....

Jerry Feather

So far, all the caps that I have that are broken or that I have seen that are broken appear to have been broken while trying to get them apart.

Jerry Feather

Bump.

Alan

I'd be pretty sure of the opposite. These can be a real bear to take apart, and also easy to scrape up with screwdrivers enough so they don't operate as smoothly.

I'd expect a tool to separate these would have been easy work for the Porsche machine shop and a worthwhile savings of time. It may not look much like what Jerry has done but I expect they either made something themselves or just got something from whoever designed & put these together for them.

Alan

Randy V

I keep meaning to send you my two caps to swap the lock into the unbroken one!

Will get it out in a few weeks.

Daniel5691

Jerry, this looks fantastic.
Thanks for taking the extra time and to document your development process.

Jerry Feather

Bump.

Jerry Feather

Randy, I received the two gas caps you sent me as promised about 3 years ago. This tool project is still about where I left it then also. I do have about half of the current batch of Pawls redrilled to the slightly deeper spring hole I decided on and will finish the rest this afternoon or this evening. Then I'm going to gather up the pieces of the nine Separating Tools and set up the mill and finish those out. I only have to mill the three fingers on the three-finger tools. I think I am going to skip the anodizing of some of the pieces. Then I'll see if I can get some of the caps apart easily.

Randy V

OK, great - looking forward to receiving my refreshed cap to replace the baggie and rubber band currently providing service!

Jerry Feather

Randy I have your two caps and I was able to take the broken one apart, but not the good one. I decided that I ought to order a shaper 3/4 inch ball nose mill cutter to do the three-finger action on the newly designed three finger tools since mine is kind of dull and I don't want to destroy any of them in the milling process. When those come in I'll set the mill up and complete one of these to see if it will work.

The original design of the three-finger tool didn't work because after it is pushed in far enough to displece the locking lugs, there is nothing to hold it in that position while the tool is turned over to push the inner part out with the tool in place. The tapers at the point of the tool simply lets the tool slip back out when the pressure is removed.

The later design of the tool has a small flat around the leading edge that is intended to allow the tool to stay in place after it is pressed into the cap so the tool and cap innards can then be pressed out.