MTFCA Forum

Top Wood late 1926 Coupe (not for purists but hopefully helpful)
I tried to purchase a wood kit but at "about 4-5 months for delivery" I decided to make our own.
This old piece of wood is all that is left to go by and has a thickness of 1-3/8".
The lumber yard had this single poplar (not ash) board that happened to be 1-3/8" x 5-5/8" x 13' 1/2" long.
The thickness is perfect.
They should be 2-3/4" wide, two of which side by side is 5-1/2", plus 1/8" saw cut is 5-5/8"...ummmm...
How much can I get out of this hardwood?
It's time for the rough cuts!

The wood was laid on top of the left side and I traced the outside edge underneath with a marker (not a pencil).
It is important that long edge of the board butts to the rear, not the front.
I then flipped the board around and continued marking the right side underneath.
Masking tape marks front and rear on the body there the board lay for marking.

Only one cut is made, but not inbetween the left and right sides.

This cut off excess piece is long enough for the rear section.

Going back to the long piece that is marked up...just cutting along the line.

The front edge markings of the side pieces are on the same side...

...and the notch must be cut out but I cannot cut all the way across the short way.
It's time to measure 2-3/4" from the edge I just removed.

And then rip the board along that new line.
Now I can separate the left and right sides...their last inch.
This other scrap which is left over will be the piece from which the front board is cut.
At 2-1/2" for the front (not 2-3/4" for the other three sides), it is perfect.

The rear piece is cut and is then marked from the cut edge 2-3/4".
A speed square with its notches for a writing instrument seems to go around the bends rather nicely.

Here are the four pieces as cut from one board...

And the scrap. I dunno, maybe body blocks.

I laid the four boards on top, which all overlap at the corners.
The square (carriage) and round wood screw holes are marked, four on the rear, plus two corners.

The front likewise has four, plus two corners.
The front board will most likely overlap as in this photo, not as shown in the one below.

And the left and right sides have four each for a total of twenty screws/bolts.

I suppose another way to look at it is 6 on all 4 sides for 24, minus 4 double counted = 20.

I am comparing our late 1926 to Don Booth's early 1926 project to show the hole differences.
Note our late short floor pan compared to his long floor pan circled in yellow.
He has marked the steel square holes and round wood holes for carriage bolts.
I have marked all the holes.
The hardware that I use will be addressed in the future.
The two rear corner bolt holes are too close to the edge of the rear board.
So, I will cut the rear board back and let the left and right sides take the full length of the bolt at the rear corners.

Finally, if you didn't catch it in the other photos...measure twice and cut once.
Also make sure your writing stick is in the correct notch.

Top Wood late 1926 Coupe
A belt sander made quick work of the interior and exterior saw blade marks.
I haven't used a router in fourty years and feel like a beginner again.

Round over and rabbet cuts.

I have different pictures of the headliner shelf existing or not existing on the front and rear ends.
While I have the router set up, I might as well do it all.
My rabbet bit only cuts to a depth of 9/16" not 5/8". So be it.

There are rivets, screw holes, and plates that jut above the surface.
The rim appears to be higher than 3/16" tall.
This begs the question: does the wood sit within the rim or is the wood notched and sit above it, flush with the outside of the steel rim?
I don't have instructions, so I choose flush.

Different types of relief cuts need to be made for the bottom wood surface to sit flush.

The front edges of the left and right sides sit on a plateau 3/16" high which also matches the height of the front piece.

So, the entire front piece needs to be shaved 3/16" on the bottom.

Cut and chisel. Drilled 5/16" holes for the 1/4" bolt shanks.

Lapping the sides and ends.

Another way of making overlapping corners.

Wood glue and masking tape bandages for a pair of splits.

Nice woodworking, thanks for sharing. When I removed the rotted wood bits from the top rails of my '26 coupe I found what appeared to be remains of some kind of bedding material in the low spots between the body and wood, I suspect it was common window glazing putty and I wonder if anyone else can shed light on this? Bedding putty, low density body filler, etc would seem like a good way to stabilize the wood base and simplify some wood sculpting. (not criticizing the sculpting, mind you) jb

Vernon,

Thank you so much for posting your "do-it-yourself wood kit" illustrations. I'm sure they will be helpful to others in the future. And it kept your project moving forward. That is also one of the advantages of the 1926-27 "steel bodied" cars -- you can use the body as the guide for lining up the wood. (Not the same for the 1926-27 Fordor -- it continued the wood frame with metal panels nailed to the wood frame) On the earlier bodies with the wood skeleton, you can and should also use the metal to help line up the wood -- but the final wood frame is used to determine how the panels will look when nailed to the frame. A lot more "trial and error" re-fitting for those before the wood frame is screwed together permanently.

Again, thank you for sharing your experience.

Respectfully submitted,

Hap l9l5 cut off

Top Wood late 1926 Coupe
Ribs - I was given this fifty year old oak church pew because it was falling apart.
So, I chiseled one board off then picked this up and let it slam on the floor, breaking cleanly into individual boards.
Wish I had it on video.


Drilling 1/4" holes for the bolts.
Trimming the overlapping corners.
Using screw drivers for alignment.


After getting the correct depth for the 3/4" hole, the bit was masked off to cut the remaining holes for nuts.


Rear, then sides over top, then the front piece, all bolted down.
Since the late 1926 has more hardware, I can't assume the ribs will go in the same place.


A screwdriver lines up the original and new top wood and the cross members location are marked.
It seems the original wood for a late 1926 was only 2-1/4" wide, not 2-3/4" !

Front to rear is 53-1/2". Rear edge to 4th cross member is 10-7/8" on center.
The 3rd and 4th cross members are 10-7/8" on center.
For the front two cross members, there is no original wood to take measurements from.


The front steel body is crowned up in the center about 1/2"...
and the rear of the steel body is crowned up about 3/8".


The oak that I have is 3/4" wide not 1", will have to compensate somehow.
Drilled down to 3/16" above the rabbet cut.
Saber sawed the two sides and chiseled out the rest.


Used a 3/8" round over on both sides to fit perfectly into the 3/4" slot.


Since the cross members are in slightly different locations, their span measurements will also differ.
Cut the ribs to length and two more round overs on the other side.

Lots of math to get the top curves cut off.


Quick work with a belt sander and then sand paper.


Countersunk holes on the rib ends for the wood screws.
The ribs themselves have a 1/4" shaft holes so that screw threads don't pull on them.
I decided not to make the undercuts on the ribs for strength.


More belt sander and sand paper action.


Started drilling one of the holes and stopped in time.
Sawdust and wood glue will fix this (and the corners) later.


James & Hap – thanks
I found some sort of putty all the way around the top of the metal even after being exposed to the elements for years. It was sticky, pliable, and yellowish but not very thick at all. I have read a lot of discussion about using a 3M product or something else as a sealant (not as glue). I have a respect for those who build these kits.

Nice work, Verne and thanks for sharing the photos.

Here’s a partial summary of prior forum posts on the subject of bedding and sealing the top wood, fwiw, jb

By Craig Anderson, central Wisconsin on Friday, April 25, 2014 - 04:45 pm:
When I removed the original top from my '27 Tudor there were no traces of any kind of sealant........just wood against metal.

By David Dewey, N. California on Friday, April 25, 2014 - 05:56 pm:
Decades ago I bedded the belt rail wood on my '30 sport coupe with a grey "dum-dum" product. It was a lot like window glazing putty, but not as sticky, and never hardens--wish I could remember where I found it, or what it's modern usage was, as I think it would be great for sealing the wood/body area.
Don't forget that originally, the headliner goes on before the top!

By Don Booth@ Bay City, Mi on Friday, April 25, 2014 - 06:27 pm:
I use pls30 Locktite roof and flashing sealant. Its cheap and remains flexible and can be removed if needed. It also cleans up nice with mineral spirit. It also sticks to anything wood and metal. Very good stuff!

By Don Booth@ Bay City, Mi on Friday, April 25, 2014 - 06:33 pm:
You can use the locktite to hold the ribs to the cross-members also. It will allow enough flex to the roof without breaking the joints. If you want to use the best then pick up a tube of 3M 5200 marine adhesive.

By Mark Strange on Friday, April 25, 2014 - 06:42 pm:
David, was the dum-dum product this?
http://3mcollision.com/3m-strip-calk-08578-black.html
It's used to stick the sheet plastic inner liner to the inside of car doors before the inner decorative panels are installed.

Top Wood late 1926 Coupe

So, the wood part is done but what about the hardware?
The original nut, removed with a straight spanner from above the carriage bolt (broken off).
All stainless steel: screws, washers, nuts, and welds are used as hardware.
This is a 1/4" 3x3 plate of stainless.


Originally, I thought the bottom of the nut was 3/8" round.


Decision time: I chose to make the top wood removable without having to remove the top material first.
All the unsean carriage bolts are being replaced with 1/4" hex or round heads.
The countersunk wood screw holes at the top of the doors stay the same but are replaced with machine screws.
Welding 3 spurs on the washers to bite into the wood and prevent turning when removing the machine screw from the bottom.


Then welding the nut on top of the washer after running a file through the washer.
I made 16 of these and installed them.
The remainder 4 wood screws secure the front center wood (20 total).

The top wood was removed and primed/painted. Ribs are numbered on the front.
The removal process was unsatisfactory in that the washer/nut combination did not perform as hoped.


So, changing directions again and making use of the stainless plate, tapped to 1/4"-20.
The math: 4 rows, 4 columns, 3/4x3/4" each, lots of time, moving slow and cautious.
At this time then screw was still a Philips drive.


At this point, making them round is not a challenge.
No - I do not want the nuts to turn when I unscrew.


Square pegs don't fit in round holes.
I struggled a long time whether to leave them as is or make them correct.
A split slot driver tool would also have to be made.

This is getting expensive per nut and is time consuming but you cannot buy these anywhere.
I wouldn't want do this commercially for $10 each.


I opted to leave them square and chisel the round holes.
The ribs are using #14 x 1-1/4" stainless wood screws because that is what retail had on the shelf in quantity 8.
The rib holes are 1-1/2" in from the outside edge.
Ribs sit on more wood since I used the 2-3/4" top wood width instead of my original 2-1/4" piece.


Welding the Phillips screws into straight. I filled them in with stainless weld and then slotted them with a cut off wheel.
These two machine screws hold the front top wood down at the visor corners.


Thank you for following my January 2022 journey.

$12 for a box of 50: https://www.mcmaster.com/oversize-squar ... re-nuts-8/
or even easier: https://www.mcmaster.com/nuts/18-8-stai ... -for-wood/