Making new floorboards.

[Mpgp1999]

I am trying to make period correct floorboards. I am starting with the rear. Currently there is plywood.  I have taken photos of my friends floorboards.  I took my dimensions and his they will be at the bottom. What type of wood is original. I have a floorboard heater I would like to install. The screws appear to be #10 countersunk slotted flat head. Maybe 1.250. What is the screw material. Was it nickel plated? How was the wood protected. Painted? Stained?

 

My Plywood size

20.875 

46.500

 

Tom Herman’s 1925 touring

Support beam 

18.375

2.000

1.000

 

Tom’s 1919 touring size

38.750

15.250

0.750

 

Back portion appears affixed

7.500

2.000/6.000 two boards 

 

Appears to be about 3 1x6

 

The first photo is the underneath of the 1925. The other two is from the 1919. 

[Taylormade]

Use marine plywood, it’s laminated with waterproof glue and holds up much better than standard plywood.

[27dodger0]

My floor boards were pine, or similar.  Maybe the Dodge Brothers followed Henry in using the shipping crates for floors?

[Dodgenz]

A treated pine board should last for years. We have different levels of treatment here for different levels of exposure- H3.2 can get wet, H4 would be exposed to rain, and H5 is in the ground. I guess H3.2 would be plenty. A stain would make it period black or dark, and personally I'd use stainless screws (or you might be able to find something more shiny..).

[Alan Cutler]

I know on '36 - '38 trucks, Ash was used on cab to frame spacers, therefore, I continue using ash on floorboards, with these fasteners, 

 

https://www.boltdepot.com/Product-Details.aspx?product=1662 the nuts from factory were welded to the underside.

 

Did the cars come with body to frame spacers?

 

[Taylormade]

The 32 Dodge Brothers sedan I’m restoring had plywood floors from the factory.  I think the earlier cars used solid wood boards.  I replaced mine - which were sadly rotted beyond repair and covered with an impossible to remove black tar undercoating - with high grade marine plywood.

[Spinneyhill]

Just be careful with treated timber against steel and with fasteners. In this country, treated timber is likely to have a lot of copper in the treatment. You should use SS fasteners and put something between the timber and the steel.

[Taylormade]

Correct, Spinnyhill.  My marine plywood is not treated, it simply  uses waterproof glue, but all the wood floors use anti-squeak fabric between the wood and the metal frame anyway, so no problem.

[RWPerry]

The floor boards in my 1925 Coupe were Pine and are the original boards. They do not look like Southern Yellow Pine but other than that I can't tell what type of pine they are.

[Mpgp1999]

If anyone has an extra floorboard that they are willing to part with let me know. I’m not very knowledgeable about lumber in Detroit in 1925. 

Whatever I end up going with I will use hardwood. Because plywood was not original. Another concern I have is with the screws. I heard that they were #10 1-1/4 cadmium plated. 

[Spinneyhill]

1 hour ago, Mpgp1999 said:

I heard that they were #10 1-1/4 cadmium plated. 

LoL! Whenever I hear "I heard" I expect to find something wrong.

 

Screw type easy. Find one that fits. CAD plating was most likely in those days but hard today so use zinc - CAD is very expensive now and for a small number, not worth it. But what about the head? @RWPerry might give you a good steer on that.

 

Timber. Just find some nice timber that will work. You have some good suggestions above, esp. @RWPerry. Don't waste time and money, just get some good long-lasting pine. Is there a book of specifications used by any AACA or Dodge Brothers or other judges? It may have the information you are looking for.

[Mpgp1999]

From what I see everything is different on my car. There is a metal part that slopes up towards the back seat. There is also two pieces of wood under a bracket. 

 

please note the back portion affixed to the backseat is metal. It has carpet glue on it. 

[Bob Zetnick]

The original floorboards on my '29 were pine (or fir) and narrow boards connected together w/ corrugated fasteners. I don't know that they were supposed to be pretty as the rear got covered in carpet and the front w/ rubber matting.

 

[Mpgp1999]

I was able to get a original bottom toe board. It is definitely made of oak almost definitely white oak. I would like to acquire an original top and front floorboard to match. I will make the rear out of white oak. I have no idea what was original in the back seat. The metal part doesn’t seem right exposed. Was the rear bare wood like in predecessor models? Or was there something covering it?  Does anyone know what those 1x2 wood under a bracket are? 

[MikeC5]

I used oak, which seemed denser than what it came with but who knows if that was original.  I also added a heat shield to the front boards since the the toe board looked a bit charred in the area close  to the header pipe.   The other thing I had to consider with using non-plywood was the area around the clutch & brake pedals.  The narrow sections across the grain are very fragile (easily broken along the grain).  I reinforced these areas on the back side to prevent this.  The board it came with had these areas chiseled out from the back side to about 1/2 thickness and then a another piece glued in perpendicular to the original grain direction to reinforce.  I can take some photos of what I did if you like.

Edited December 20, 2019 by MikeC5 (see edit history)

[Mpgp1999]

Maybe the rear metal portion was painted or covered somehow? Was the rear floor board bare wood?

[Bob Zetnick]

On my '29 any exposed metal  is covered by carpet....that includes the front and back seat risers.

 

[Mpgp1999]

That makes sense. From what I can tell. The metal was painted black. May have been covered with carpeting. If anyone has a top toe board I would be interested.