willysmjeeps.com

Per TM9-1804B:
"All major panels are
of No 18 gage steel."
Is this to say that the floors are 18? Would it be recommended or overkill to buy 16. I would rather just buy one large sheet and would rather it be 18 because I see it being a little bit easier to work with.

Yes the floors are 18. Many aftermarket replacement floors are 16. The 16 is a good idea if you are not putting new wood back into the hat channels.

The hat channels are supposed to have wood in them?

Yes, they came from the factory that way but 60 yrs later
the wood is usually rotted away. Unless you are replacing floors
you can't access the interior of the hats to replace the wood.

Was the wood there just to prevent the mounting bolts from crushing the floor panels or to add rigidity. Or both? From what I've seen, repo's just have a section of tubing where the body mount bolts go thru. Perhaps they (some) are using heavier material to compensate for no wood.

I think both, Brett. Looking at it now it seems foolish
to use wood-but remember no one was counting on
any if these rigs to be around 60 yrs later.

The only part I have ever found on the A1 that is not 18 GA. is the floor riser which is 16 GA. It is important because it creates the rigidness in the tub. For body panels it's overkill.

The wood inserts I always have thought were pretty clever. The Willys engineers were genuis at what they were able to do.

Steel and aluminum being valued products in wartime Willys managed to reduce the thickness of the hat channels and front bumper by reinforcing with wood. This reduced steel consumption.

For a factory class resto they are necessary but otherwise I would use the short pieces of tubing to prevent crushing when tightening the body mount bolts. The 18 gauge floors were a wartime compromise as well and do much better with 16 gauge.

I went to local sheet metal fab shop in town yesterday and got 2 sheets for the floor and enough lengths of hat channel made to fabricate and replace all of the existing rusted out stuff. They were able to make both sizes of hat channel. All out of 16 ga cold rolled steel. Should be stout! They also threw in some misc 18ga sheet for some body repair. Nice guys, must be why they have been around for 110 years.
All for $60

Has anyone thought of using that plastic composite deck material
for the hat channel fillers? Easy enough to cut. Can probably
get it to the right size without problems. Won't ever rot.

Adding the labor and PITA for something unseen when the jeep is displayed is hardly worth it. If one is going to put forth that much effort when the additional strength is not needed and a factory resto is the goal then do it right and use the correct wood product.

The only place this idea would make any sense is the bumper reinforcement.

Hi Wes,
I was wondering if the extra strength was necessary on a daily
driver and one that would see some off roading. The twisting and
flexing was what I was trying to reduce.

I will replace the old oak bumper reinforcement with another
piece of oak. I have some laying around and can cut and drill it.
I will treat it like railroads used to treat wood on the old cars,
with several coats of boiled linseed oil, then oil based paint.

That one you can see.

Thanks,