Roof joints

[Patcon]

While I was at Zcon in Atlanta I got to spend some time with Gnosez at the car show. It was a lot of fun and very informative. While we were talking, we ended up on the topic of the Bad Dog frame rails that Gnosez makes and markets. John was telling me that when the frame rails get added to the floor boards they should not be fully seam welded. They need to be spotted in with gaps between weld sections. John was telling me when people have disregarded his advise and fully welded the floor seam, cracks have appeared at the roof joint at the top of the hatch. We were wondering about that joint and since Matsuo San was just a few feet away, we went to ask him about it. When we asked him about that joint, Matsuo San said the car needed to "breathe" and they put that joint there at the hatch. The idea was that the movement, from the car flexing, there at the hatch was better than stressing the A pillar and cracking it instead. He also said that since the chrome window frame is not structurally supportive, it needed to be like that. If the door had a real frame around the glass it might have been different. So for those of us, me included, who have considered making that joint more substantial to prevent cracking, that is not such a good idea if you like your windshield to stay in the car.

John may have more to add as he was interpreting for me...

[madkaw]

Interesting ! Some things to consider with my race car ( well someday ). John as good people and shared with me some experience he had for working with Rebello and it was helpful. 

So bigger connected rails are okay , but only spot weld ?

[Patcon]

10 minutes ago, madkaw said:

Interesting ! Some things to consider with my race car ( well someday ). John as good people and shared with me some experience he had for working with Rebello and it was helpful. 

So bigger connected rails are okay , but only spot weld ?

We talked a little about Rebello too.

John said to leave a gap of like 1 1/2" or so and seam seal after your done.

[madkaw]

On 10/24/2018 at 7:36 PM, Patcon said:

We talked a little about Rebello too.

John said to leave a gap of like 1 1/2" or so and seam seal after your done.

So close to factory !

[gnosez]

Sorry for the late reply.  The late John Coffey and I had several conversations regarding why the "C" pillar develops a crack with the  leading reasons being (in no particular order):

• Age of the vehicle
• Usage (rough roads, track or autocross, etc.)
• Prior damage
• Addition of a full cage
• Addition of continuously seam welded BDP frame rails

As Matsuo San stated the leaded connection between the rear quarter panel and the roof ( C-pillar) was done to ensure if anything cracked it would be this and not the windshield connection. Picture in your mind a failed A-pillar causing the windshield to fall back into the driver and passenger or fly off and crash into another vehicle. I can only imagine that these were considered along with the number of lawsuits Americans file each year and they decided to just lead that joint instead since Mr. K was very much against a different style door window trim design. He went on to say that under normal driving conditions it should not crack but then turned and gestured towards me and said "unless you drive like John". 

People install our frame rails for any number of reasons but I suspect that most do so because they have increased the HP/torque in a 40 to 48 year old unibody made to house a 150HP engine.

[Patcon]

53 minutes ago, gnosez said:

Sorry for the late reply.  The late John Coffey and I had several conversations regarding why the "C" pillar develops a crack with the  leading reasons being (in no particular order):

• Age of the vehicle
• Usage (rough roads, track or autocross, etc.)
• Prior damage
• Addition of a full cage
• Addition of continuously seam welded BDP frame rails

As Matsuo San stated the leaded connection between the rear quarter panel and the roof ( C-pillar) was done to ensure if anything cracked it would be this and not the windshield connection. Picture in your mind a failed A-pillar causing the windshield to fall back into the driver and passenger or fly off and crash into another vehicle. I can only imagine that these were considered along with the number of lawsuits Americans file each year and they decided to just lead that joint instead since Mr. K was very much against a different style door window trim design. He went on to say that under normal driving conditions it should not crack but then turned and gestured towards me and said "unless you drive like John". 

People install our frame rails for any number of reasons but I suspect that most do so because they have increased the HP/torque in a 40 to 48 year old unibody made to house a 150HP engine.

Finally, the actual translator