Alan

Jerry - aside from getting to the mounting points I see no reason why the existing GTS liners are not rounded more in the longitudinal direction - the boxy shape actually makes them weaker and serves no real purpose - it also makes them bigger and therefore more difficult to install... having a variable gap around the tire circumference seems to me to make it rather more likely that debris thrown up will damage the liner (maybe). Stick with it - replicating the original is not the goal they are absolute crap - so do come up with somthing better. I have confidence you can - your spare tire cover was great!.

I am happy to contribute to this - where do I send my paypal payment?

Alan - Happy Customer !

Jerry Feather

Thanks everyone for the offer of money towards this project. As I mentioned, money is not an obstacle in this project. What little money was required has been spent and the material is on hand to get at least some prototyping done. Actually, with the level of success I have been having with some of this, the prototypes will likely be limited, and even those will likely be servicable.

Please do no send me money. I suggest that you each hang onto the money that is offered and let it become a part of the cost for this product when I offer it in my sponsorship or perhaps for the shipping. The offers have performed a very useful purpose already, and that is to give me a jump start back onto this project.

I have three things going at this point, actually four when you count the need to put up some new shelving and make some needed space. I need to meet my commitments on the console project also and am going to have it all in the que. I actually function best with three or four things going at the same time, expecially when I am not hung up on one of them. I think my hangup on the oven is getting cured.

Thanks again to all.

Jerry Feather

RFJ

Yes, what he said, no current to groung,this is why ground fault curcuit breakers are made and they come in 240 volt so you could put one on the oven unless it is huge. they are expensive put save lives, just my two cents, Ray ps please make sure your wire insulation is rated for the temperature it will see

77tony

Great input from all. Really like where Jerry he is heading on this project. Lets keep the ball rolling and get these upgraded WW liners out there to those in need. T

Big Easy Sharkster

Jerry, just for the record, I'll need these liners for my GTS also. Not sure from reviewing the string above whether yr making all 4 WW liners for the GTS, but, it seems to me that the back ones (especially left side) seem to fall apart 1st.

Thanks

Jerry Feather

I am making the REAR wheel weel liners, primarily for the GTS, but also for what I think can be all of the other cars, or at least back through the S4's.

I have, in the past, given only a little thought about trying to adapt my process and new blow oven to forming something for the front of all the cars, but, like you say, they seem to hold up better that the GTS rear liners.

I picked up today where I had left off on the oven. I got some of the sheet metal that I am using for an outer skin to hold in some insulation so I don't burn myself in poroduction. That is going pretty well. When I get it finalized I'm going to try to get some help and set the thing upright off my welding table.

I have given some thought to wire insulation, but actually all the wiring is going to be outside the oven and not subject to much direct or even indirect heat. It will be in conduit around and under the outside. The only place it will be close to the heat is right at the end of the coils, and that will be in junction boxes.

Jerry

Hilton

Just a minor point Jerry - all GT's, and an increasing number of S4's have their rear fender lip rolled flat, rather than sticking out at right-angles. This allows increased space for tires/wheels.

Will your design take account of this and fit those cars too?

EspritS4s

Jerry Feather

Hi Hilton. That is a good point. I had discovered that before in the first thread about this project when others had posted some very helpful pictures for my review. I may have to review those again when I get closer the making the forms. Tentatively I am expecting to make the new liners so that the outer edge that meets the wheel opening follows the opening fairly closely and that the outer half of the new liners will be mounted to the inner half after being placed snuggly against the inside of the "fender." I expect the liner edge to be a close match to the wheel opening arch, but with a slightly larger radius so it wont have a tendency to make like "your slip is showing."

Once the outer half of the liner is fastened to the inner half and to one or two mounting points front and maybe rear I think it will be firm enough not to be moving around any. The whole liner is going to be kind of "loaded" when it is installed and will not be floating any at all.

Others have mentioned a couple of times about the difficulty of installing and removing the original liners. The new ones will be put in and removed a half at a time, so they will be much easier to deal with.

Thanks.

Jerry Feather

Glenn M

Jerry,
Would love to have the outer half wider than a GTS for my Strosek if possible.

Keep up the great work.

hb4

Jerry,
I would be surprised if the there were any electrical connection to the coils except at the two ends (meaning that the ceramic lining electrically insulates the heating electrode from its mounting structure.) If that's the case, then the metal outer shell should be grounded via a mechanical connection to the oven and the oven then grounded back to the panel ground (not NEUTRAL) bus with a green wire in the three wire cable that connects the oven. That way, if any part of the electrode shorts to any other metal part, the circuit breaker will trip.

You didn't mention whether there are controls for the oven. If they are 110V controls, then you'll need a four wire cable, with the fourth (white) wire connected between the neutral bus in the panel and the neutral connection in the controls. The hot connection in the controls can be connected to either of the 220V coil wires, since either one will provide 110V to neutral.

AC and DC are really different animals; in this case it's almost as if you had two six volt batteries in series - with the common connection being the neutral and the end connections flip flopping 60 times a second.

Bill

Jerry Feather

Hi Bill. First I want to say welcome, and that I am honored to have your first post in your new membership in this thread. Then I want to say thanks for your helpful information.

The only control I plan for this oven is an on-off switch. I bought one that will include both legs of the hot sides of the circuit and I think will handle combined wattage (or amperage, I'm always a little mixed up on that) of the combined heat coils. I think they are 3400 of one or the other each (I'll go with watts since I know amps are usually pretty big). Actually I think the switch is just barely heavy enough, but I also think the "duty cycle" I am going to deal with will be fairly short. I think my switch is a two pole single throw.

I am pretty much going in the direction your information would indicate, but probably only partly by accident. What you describe is just the way I have the oven set up to this point. I think the thing that you are clearing up for me is that with 240 volts AC there really is no need for a neutral wire. It sounds like if I were to grab both hot leads in the 240 circuit I am going to get a big surprise, even if I am not otherwise grounded. That says to me that when the current is going one way in one lead it is going the other way in the other lead. In other words, each lead is alternating between positive and negative 60 times a second, so there is no need for a seperate neutral.

Now, I wonder why some 240 volt outlets have four holes and some have only three. I think mine is going to have only three. In fact, that is what the plug has that I think I bought already and I am going to plug it into my welder outlet which also has only three.

The reason I'll not try to have something like a variable temperature control is partly because It will be much more complicated to wire it all up but mostly because I have found that in heating this plastic it does not work too well to try to heat it to a certain temperature and hold it there until I can get to it to form. Rather, I have to turn on the heat and then watch the temperature rise to the correct point then form at just that moment. I will be doing the same with this project. Fortunately I anticipate that I will be getting the temperature up in a fairly short period.

I expect to put the plastic sheet over the top of the oven chamber the put the form over that and clamp it all down to the oven structure all around. Then with the heat on I'll have to watch the plastic to see when it reaches forming temperature. I may be able to tell that point by watching how much it sags into the oven or I may be able to measure the temperature with my infrared thermometer. When my plastics guy does this in his vacu-forming process he simply times it.

When it is hot enough I'll simply turn the heat off and turn on the air and blow the plastic up into the form and watch it while it takes the desired shape. Since the form will have a lot of open space into which the plastic will be forming I'll be able to see and perhaps gauge the exact shape I need. Then I'll have to keep injecting air a little at a time to keep it there because the plastic has a strong memory, a tendency to shrink, and the oven will probably leak air a little. Also, the plastic holds heat for a little while before it is cool enough to stay where you want it.

One nice thing about the plastic having a good memory is that if a given sheet is not formed correctly, I can simply turn the air off and turn the heat back on and do it over. I can't do that after trimming obviously, but that will reduce the potential for waste which would otherwise occur if a "blow" is malformed. It also will give me the initial ability to tell if the form is correct in any given respect which can be changed and then the plastic reformed.

Thanks again. Good to have you with us.

Jerry Feather

Jerry Feather

Hi Glenn, Great to hear from you.

I have thought about your suggestion before and think I know what will be needed to make liners for your car with the wider modification. I don't think the GTS outer halves are going to be adjustable to meet your specific needs. I am planning about a one inch overlap of the inner and outer halves of these liners, both for the GTS versions and the earlier ones. That means that the form for the GTS version outer half will be forming about an inch "deeper" than the others. I don't think the depth will be a problem since I think I will be able to form roughly up to an amount equilivant to what would be a hemisphere.

For us in this discussion I don't think that means very much, but it is something that I have to keep in mind when I invision this plastic taking shape in a form, which I have to do in designing the forms.

Anyway, depth of forming will not preclude me from forming deeper liner halves. What I will need to know is how far out your fender is from either the GTS or an earlier car and the exact shape of the wheel opening. I also will need to know something about the exact position of the wheel opening relative to something on the original car before modified. I'm not sure what that might be on your's.

What I am going to use for placement of the wheel opening in the forms for the GTS and the earlier cars is the line in front and rear of the wheel opening that is made by the plastic rocker panel and rear bumper covers on the S4 and GTS cars. I think that line is common to both. I don't think your car has that, so we will need to determine a different reference.

One important thing that your input tells me, and it helps me make an important decision, I think, is that the best way to design the form for the outer halves of these liners is going to be to make one form, but with interchangable bridging that will be used for at least the two applications, but can then also be changed with some custom bridging for something like your application.

When it comes to that we can talk about what will be involved in bridging for your application. Fair enough?

Jerry Feather

Alan

Jarry - No need to do the fronts - the material and construction for the fronts are fine (basically last forever), they are universal fit and they are relatively inexpensive... just focus on replacements for the expensive & crappy rears...

Alan

Jerry Feather

Thanks Alan. That is pretty much the direction I am going. I have some front liners and you are right, they are a completely different animal. However, I think my blow oven will be able to accomodate some suitable re-design for front liners if the need does arise.

For those who may wonder what I am actually doing that conforms with the supposed progress I have been posting, here is a picture of the blow oven on my welding table upside down in its present form.

I'll post some more pictures of the underlying structure when I have an opportunity to take the aluminum covering off after I get it lined up for fasteners.

Enjoy.

Jerry Feather