Floor pan options for my DB1

[na94]

Here is the complete write up:

http://thinkfastengineering.com/2012...modifications/

If you like that kind of content, you might consider buying a copy of my book Think Fast - The Racer's Why-To Guide to Winning. It also includes a description of how I do torsional stiffness tests.

http://thinkfastbook.com/

As it happens, I do have a copy =) I will have to re-read it. Mind like a sieve =/

[na94]

Bringing this post back from the dead.

I can't quite seem to understand how I should be spacing my rivets in the additional 1" wide bonding strips that I added to my frame.

Steve, you suggested using 4 rows of 5/32" rivets. The reading I have done indicates that transverse pitch (row spacing) is usually 75% of rivet pitch (rivet spacing), and should not be less than 2.5 the rivet diameter.

What am I missing here?

Also, I am spacing my rivets at least 0.25" from bead welds in the corners. I assume this is sufficient?

Thanks.

[S Lathrop]

Bringing this post back from the dead.

I can't quite seem to understand how I should be spacing my rivets in the additional 1" wide bonding strips that I added to my frame.

Steve, you suggested using 4 rows of 5/32" rivets. The reading I have done indicates that transverse pitch (row spacing) is usually 75% of rivet pitch (rivet spacing), and should not be less than 2.5 the rivet diameter.

What am I missing here?

Also, I am spacing my rivets at least 0.25" from bead welds in the corners. I assume this is sufficient?

Thanks.

The rivets that go into the tubes (blind rivets) I space 5/16 or 3/8 on either side of the center of the tube (assuming 1 x 1 tube). I use the same pattern on the rivet strips. I use 1.5' spacing along each row but I stagger the rows so that there are 2 rivets every 3/4" along the frame and rivet strip.

[na94]

The rivets that go into the tubes (blind rivets) I space 5/16 or 3/8 on either side of the center of the tube (assuming 1 x 1 tube). I use the same pattern on the rivet strips. I use 1.5' spacing along each row but I stagger the rows so that there are 2 rivets every 3/4" along the frame and rivet strip.

Thanks, makes perfect sense.

Since my frame already has holes in the center, I will leave those and add 2 rows in the bonding strips @ 1".

Thanks again.

[Craig Henry]

Steve,

1) When adding the 18 gauge 4130 1” wide strips I’m assuming you use TIG stitch welds as MIG isn’t recommended for 4130 correct?

2) Does the 120 minute epoxy allow enough time to buck all the added rivets (only in the added strips) or do you use Avex rivets temporarily, let the epoxy cure, then drill out/replace them with bucked rivets? I'm new, thus slow, to bucking rivets... my pneumatic "pop" riveter, with Cherry rivets, is fast.

Thanks in advance for the help.

Craig

[steve zemke]

Steve,

1) When adding the 18 gauge 4130 1” wide strips I’m assuming you use TIG stitch welds as MIG isn’t recommended for 4130 correct?

2) Does the 120 minute epoxy allow enough time to buck all the added rivets (only in the added strips) or do you use Avex rivets temporarily, let the epoxy cure, then drill out/replace them with bucked rivets? I'm new, thus slow, to bucking rivets... my pneumatic "pop" riveter, with Cherry rivets, is fast.

Thanks in advance for the help.

Craig

Hi Craig, I do nort know if the Steve you are referring to was me or Steve Lathrop. I used Hysol mixed in the reccomended ratios and had plenty of time to buck all the rivets. I used four rows of rivets on each side. You just need to plan you clamping strategy for the middle of the frame. I started from the middle and worked my way out in a circular pattern. I had a friend help me with the bucking and we were done in plenty of time before the Hysol began to harden. Good luck with your project. The main purpose for the rivets is to clamp the glue in place while it cures. Many glues are stronger when thinner.

[Craig Henry]

Hi Steve Zemke,

I was asking Steve Lathrop but I greatly appreciate the detailed and helpful info you provided. Just need an answer to my MIG or TIG question.

Craig

[jrh3]

Curious why the constructors don't use something like 3/4x2" on the lower rails instead of welding on 1" strips.
Couldn't be more than a few pounds increases weight.

[Marty Nygard]

See https://www.harrisproductsgroup.com/...rome-moly.aspx

[S Lathrop]

See https://www.harrisproductsgroup.com/...rome-moly.aspx

TIG only.

My experience is that when I see a MIG weld, I can usually find 2 cracks, one on either side of the bead left by a MIG gun. With a TIG torch you have a lot better control of the weld and how the filler metal is applied. With TIG you can do the welds and have very little grinding to get a good flat surface to bond to.

The tabs or strips that you are adding are structural to the frame.