Here’s the latest and greatest on the 70 Degree Racing subframe tank, as of 02-24-10.
I was out at the molders on Thursday 2-18-10 to hopefully iron out the final details of the model so it could get sent off to the female shop, and then on to the foundry.
The molder had given the model project over from Tom to another model maker, Paul and I was advised of this before arriving. As usual I brought my bike and my scissor stand to make disassembly and assembly of my bike easier, as well as being able to use my bike as the mule to fit the model to.
When I had left last time it was understood that one of the sub frames we had provided was going to be cut up and the inserts removed and sent out to be copied and inserts produced to be used in our tank. Upon my arrival this time I found that had not been done. After taking the rear clip off of my bike to make ready for Paul to do his fit test for the model, I was looking for something to do and ended up cutting all of the inserts out of one of the sub frames provided to the molder after it had been cut up by Tom. I also found out that the molder, who had originally said that he could have the inserts made was unable to do so, and I am currently having these hard mounting point inserts made.
These are the inserts from inside the sub frame. The top insert in the picture is from the right rear of the sub frame and takes the vertical 8x26mm bolt (this is the one we had to redesign-see below). Starting on the bottom row left side, the first two are the bottom hard points, one for the left and one for the right, the wider one is the upper hard point from the lower left side, and the other two are the muffler hanger inserts.
It was around this time that Izzy, the mold maker came over to express concern over how one of the stock inserts protruded from the sub frame as this could cause a leak point to occur during the actual tank making process. This is the left rear vertical mouting point, from the outside, and the second picture is looking at it from the inside. The problem is the bare aluminum sticking out of the plastic, as this helps to create a path the "could" allow gasses that occur during the molding process between the mold and the plastic being molded to run down along the side of the insert and make a pin hole. This will be aleviated by cutting down the insert on the top, lengthening the 8mm thread section downward into the unused 6mm thread section to create a flat surface on the top. We will include a longer 8mm bolt and a crush collar to take up this space between the bottom of the horizontal sub frame truss, and the sub frame itself.
I have to say that this became quite an undertaking to engineer how we were going to solve this problem. Izzy had several suggestions, as well as Tom, however, each of their suggestions required the purchaser to make modifications to the horizontal sub frame or sub frame second part as it is referred to in the parts book.
This is NOT an option that we at 70 Degree Racing liked. We want to produce a replacement sub frame/ gas tank that is a bolt on affair only.
I spent the next several hours trying to figure out how to utilize the space that is available, and modify the insert to make the sub tank be a bolt on affair, yet make it so that there would not be any leaking concerns as expressed by the mold maker. In the end I was able to figure out a way to have the cake and eat it too.
While all this was going on, Tom and Paul was locating and drilling the lower hard mounting points on the model.
Late in the day the model was finally ready to place on my bike to check the fit of the lower three hard mounting points, and the hard mounting point in the top back of the model where the sub frame bolts to the sub frame second part, or the vertical 8X26mm bolts all the way in the back of the sub frame second part. While this may seem somewhat straight forward it is not, the model itself must be “plussed up” to allow for the shrinkage that occurs during the tank making process. IE the XLPE plastic shrinks inside the mold as it cools. And when one considers all the different directions in which the XLPE will be shrinking in relationship to these top two bolts in the back, and the effect this shrinking will have on the overall placement of the tank…….well you get the picture. Anyway, once we got the model mounted onto my frame, it was apparent that Paul had got the top rear mounting points right on the money.
These, and the rest of the hard mounting points will be finalized in mold itself after the first tank is produced which will not have any of the screw or bolt holes in it. This is to allow for proper placement of the screw holes and bolt holes, regardless of the calculated shrink that will occur. This is the same process that all tank or plastic molders utilize to ensure proper placement of the mounting hardware.
To say that this tank is more complex to produce that a standard oversize gas tank is an understatement. The molder had based his original delivery time for our tank using a tried and true schedule, as well as the inserts not having been cut out and duplicated, long story short we are about a month behind the schedule that we originally thought we would have as far as delivery goes. So at this point we are thinking that the end of March will be when we start to get delivery of our tanks. I know that I was bummed to figure this out, and I’m sure that all of you who are wanting these tanks are too. However, progress is being made, and the 12 hours that I spent at the molders on this day was not wasted, as there was some other fine tuning of the model that needed to be done as well as all of the aforementioned items.
All of the other associated parts for the sub tank are in our possession, such as the quick disconnects and adapter plates, and now we are just waiting to get the tank mold done.
About all I can say at this point is to please be patient, progress is being made, and we are doing everything we can to get these tanks to market. I know I could have used one the other day when I was out riding as I was getting really close to having to bum some fuel from my buddy on the way back to the truck.
I have included several pictures from this latest trip to the molder, and as you can see things are taking shape.
Thanks Dale E O!