No Convertible top, No problem - 1920's Buick missing top bows and sockets

[Hubert_25-25]

What do you do if you are missing the iron top sockets and wood bows on your antique car?  My intention of this posting is to provide guidance on putting a top assembly on a convertible.  The complexity goes way up if you are missing the top sockets and the wood bows.  This foundation has to be installed correctly before any fabric can even be added. 

 Some history.  The body and chassis is a 1927 Buick Master model 47 (4 door sedan)( 120" wheelbase).  The hood is from a Master and the body from a 1925/1926 Buick Standard Touring model 25 (116" wheelbase).   The width of the section between the doors may or may not be correct.     

- The most value that can be added to this car is to install a convertible top.  

- This job started as an upholsterer approached me about doing a top on an early Buick.  I sent him instructions, and then he said he did not have the top bows.  So Larry DiBarry provided dimensions on the top sockets and bows from his 1925-45.  These are in the table below.  The length of the wood that is in the sockets is unknown, so I used the dimensions that were used from my 1925 -25 when I rebuilt that top.  The reason for creating this document was to have dimensions to have new wood bows steam bent. 

- Later the upholsterer said he was unable to do the work.  The car came to me with two sets of top sockets.  I was not aware that these were not the Buick top sockets for this car.  So technically not "missing the sockets", but hoping that one of these non Buick sets function for this Buick.

- I have solicited help from Larry DiBarry and Mark Kikta to get finished top dimensions.  I need to find the ballpark where the bows should be to have the correct look.  This is a first step of finding a similar car where someone can provide some dimensions.  

So I will do some postings as I figure out the best way to recreate this structure.

Hugh

Edited September 5, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

So the first 2 photos are of the sockets that were shipped with the car.   The socket with the eyelet is the last socket and the eyelet is for for the body pivot bolt.

In the first photo,  notice how high up the top mechanism is on the last top socket.  

In the 2nd photo, this is the top sockets that we will be using.  The pivot is midway on the last socket.

The 3rd photo are dimensions from OEM Buick top sockets used on a 1925 Buick model 25 touring car. 

The 4th photo is the 2nd photo with dimensions.

The last photo is the extended dimension of the sockets we will be using. 

     Compare the 2 photos of the socket assemblies with dimensions.   Notice how different the construction is.  Buick used a "double bar and parallel bar" assembly.   The double bar is two equal bars with spacers between.  The first photo has this "double bar" detail, but it is not a good fit for this car.      

 

 

Edited September 5, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

 

This first photo shows the last socket with the top mechanism that is very high on the last socket.  The top mechanism should be fairly parallel with the top of the doors when installed.  This set would have to be pushed very far back as the height from the door tops at the front door was 19" and it was 27" at the back door.     

 

The other set of sockets looked much better once opened up and set against the car.   Using 3/4" PVC and a little bit of 1/4" rope, the front and the last bow were replicated.  These can be moved a little inside the sockets to fine tune the shape.  The intention is to verify where the wood bows will be relative to the 2 drawings with dimensions that I received from Larry and Mark.   Larry has the last bow at 18" high from the rear tub, and Mark has his at 22".  My 1925-25 was 19 1/2".   This height is effected by two factors.  How far in the socket is bow #4, and/or how far in the socket is bow #1.   The "back curtain" also needs to have a slight slant of the "top to the rear".   Minimum is vertical, but it should slant back some.    

 

Since I feel I am going to be struggling with too much height at the rear, I am going to fit the last bow first.  I am going to put it as far as I can into the last sockets.  Once the curve in the bow starts, they can not go any deeper.  So the last bow will get installed first.  

Hugh

Edited September 5, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

The last bow in the top set is similar to all the others, but on some cars, it is wider than the others.  On a Buick Touring car, Bows 1 thru 3 are 1” x 1 ½”, while bow 4 is 1” x 2 ½”.  The last bow is made “offset” as there is a flat side (on the bottom when the bow is in the folded (rest) position).  The last bow is the one to install first.  Attached are 4 wood bow drawings with dimensions from my Buick 1925-25.  In the first drawing is a side view of this last bow.  This is the basic design of how each bow will be cut.  Notice also in the last photo that there is a stiffener board that is attached to the last bow, but it is not steam bent.   

 

It will save time in the long run if you lay out the bow centerline and the side distances first on each bow on the work table.  Steam bent bows aren’t like a stamped part.  Some areas bend just a little differently.  The right side is not necessarily a mirror image of the left.  I like to use a straight edge and 2 points about 16” from each side of center.  Then I mark the bow ends at 12 inches from the center wood.  Each side of the scrap ends of these bows are a different length to that line, so measuring from the mid section will make a more symmetric top.  From these initial marks, I measure and mark where the bow cut off will be, and how deep to make the socket insert.  In addition I use a small drill bit to make a tiny dot to mark the wood in case the pencil marks get knocked off.         

[Hubert_25-25]

Now the time consuming part – fitting the socket ends.   The bow is cut to length on both sides.   I made a template from some heavy paper of the wide end of the top socket.  This is the profile that the wood must conform to first.  I transfer this oval size onto the end grain.  As stated before, there is a flat side to the rear bow, so this profile is drawn on the bottom of each end grain.  A reciprocating saw is used rough cut the socket end and to make the transition in size to the wider portion of the bow.

The tools used in this step are:

1)      Recriprocating saw for rough out cuts

2)       Circular saw to rough cut the slot for the socket seam

3)      belt sander with 40 grit band

When sanding, there is almost no sanding on the flat sides of the wood bow.  It is mainly trying to get the rounded contour and the taper correct.   For fitting the end of the wood bow into the sockets, start with getting the first inch into the socket without removing too much wood.    You have to clamp the wood bow in a bench vise.   Make 2 pencil lines ¼” apart to indicate where the socket seam is.  Use a circular saw and carefully rough cut this slot.  Now almost all the work is using the 40 grit paper in the belt sander. 

1)      Slide the socket on (but not too tight), wiggle it.

2)      Pull the socket off.  It will leave “tight marks” on the wood.

3)      File with the grain and remove just the dark spots.

4)      Repeat – A lot

 

Hugh

[Hubert_25-25]

Now it is getting interesting, because I am using non stock top sockets and starting to check the fit again after the first pass with just PVC for the bows.  So the rear bow is in and it is all correct.  The rear wood height to the back of the tub is 19 inches.  So now I really need to do Bow #1 to get the top frame stiffened , and to ensure bows 2 and 3 hit in the right places.  Now folding the top we begin to see the problem with the non Buick top sockets.  Bow #1 (on the top of the folded stack) projects 8” further than if using Buick top sockets.  Most noticeable in the side view as typically wood bows nest closer to each other.   Not ideal, but not a deal breaker either. 

1)      Doubtful that this top will be folded once installed.  If it is folded, it is still functional and many of these old tops on touring cars hung out significantly past the rear of the car back in the day.  Ever looked at a VW Bug with the top down?   

2)      I do now have access to a set of more correct Buick top sockets (Thank you Frank Freda) but I also learned that some of the sockets need repairs.  The repair estimate for the sockets is in the neighborhood of $1,000 plus the cost of the buying the sockets.

3)       The owner is looking for functional and not concours.  

So on to more sanding and cutting wood bows.

Hugh

Hugh

 

[EmTee]

Hugh, thanks for the detailed explanation - very interesting discussion.  I think if anyone can pull this off, it would be you! 

 

[dibarlaw]

I always aplaud Hugh's thoroughness in detail. He has a tough engineering problem. Considering that he was given the earlier style sockets to deal with instead of the later 1927 and newer plate type irons. These have the wood aplied to the outside of these plates.

 

[Hubert_25-25]

Good progress yesterday as I was able to fit all the bows and install it on the car.  I will need to remove it later to blast and paint or powder coat the socket assemblies.  

One other item that was a big help was a "Japaneese Z cut" saw.  These are a pull saw.  Flexible blade.  This saw really helped with fitting the top wood bows into the sockets.  If you don't have one of these saws, you are missing out.  Expect to spend a couple hours on each socket end working to get a good fit and getting the wood deep into the socket.

Photo number 4 shows the extra length of the front bow due to the incorrect sockets.   The front bow is 8" longer than stock.  Bow #2 was 4" longer to make the math work to keep the distance between bows 1 and 2 at 39 inches.          

I did lay a board across bows 2 and 3, and I have good height relative to bows 1 and 4.  

It would have been nice if the top frame were the "metal bar" type as Larry referenced.  A person could use the dimensions at the top of this thread and create a metal frame assembly and then cover it afterward with wood.  A good alternative.  

I have several attachment brackets to make and I have to add the wood around the rear tub before I can start installing fabric.

Hugh

[dibarlaw]

Great work Hugh:

 As you know by this time the designers of these tops were trying to make a neater, less obvious stack. In an ealier post you have the factory imgage of the 1927-55.

Below is what my top looked like before I learned the correct sequence of folding. Including photo with the bent and welded up shortend sockets. I have since straightened these bends. The width of the bows to be narrower at the windshield and the wider at the rear tub. Mine were all the same width front to rear.

   

 

The only factory image I have found showing our 1925-25 with the top down and boot on. The

fellow who did my slip cover type boot for my cobbled up top indicated that the image was in error. That, no way, could all that top fit in the "dust cover". Not unless there were no pads and such on the bows. Our 1925-25 bows/sockets are to "nest" a bit which my cut down older bows just stack on each other.

        

Temporary pattern for the finished vinyl cover with loose foam padding "falsies" to fill out for more smooth form fitting appearance.

The boot actually fits the correct original design top for my 1925-45 Master much better. Witout the extra foam padding I have to use for the Model 25.

 

 Unfortunately with what you have been given to work with this will not be possible with how far out the front bow extends out. On my Model 25 car the front bow sits about 6" to the inside of the stack. With what you have will make for an interesting top down appearance.

 Keep up the great work!

 This may give me the insentive to start on my new top bows and sockets that I have had laying around for 3 years or more......

    

 

 

Edited September 13, 2023 by dibarlaw
spelling (see edit history)

[Fr. Buick]

I have top irons from a 23 4 cylinder touring if that helps any.  Heavy parts for you to pay shipping, but yours to use for free - maybe for sundry parts?

[Hubert_25-25]

Fr.Buick   I will PM you with details.   Thank you.      Hugh

[Hubert_25-25]

Larry brings up a good point about later bows being narrower front to rear.  A styling trend.  Early cars used all bows the same in many cases.  It helps if another owner of your make and model can provide a few of the basic dimensions to get the top in the ball park of how it looked originally.  I too am looking forward to seeing Larry's new top on his car one day.      

I wanted to add this slide because I feel I left something out.  I had 2 sets of top sockets to choose from for this car.  If you can get a person that has top sockets to lay them open and take some measurements, you may be able to find a set that will work.  So this dimensional diagram gives some guidance.  A person could draw the segments to scale and make a mock up of the design.  The important thing is 

 - Dimension A - height from doors to top frame at the front. 

- This needs to be very close to dimension B, so have a person open up the sockets and on a break in the concrete, set A equal to B and photograph the sockets.  Then get a few dimensions and see how it would fit on your car.

 

 

This photo shows the socket set that I did not use.  

When I laid this out next to the car, Dimension B is much taller than Dimension A.  About 7 inches taller.  This tells me that this set is for an older make or model when the windshields were taller.  It looks very much like a Buick design to me.  It is looking for a home.  At some point I will take another photo of this like above if someone shows an interest in them.  This is a good solid set.   

I'm also going to show you this pile of top sockets and front bumpers in the Arizona desert.  No labels so no one knows what they belong to.  

 

 

[Fr. Buick]

I sent you a private message with a picture of the 23 4-cyl touring irons you might be interested in, FYI.

 

Doug

[Hubert_25-25]

Fitting the rear toneau wood surround.

The wood around the rear tub serves 2 main purposes.  The top side of the wood across the back accepts the tacks for the seat back covering.  The back side of the wood across the back, holds the tacks for the tops back curtain.  On the 2 sides of the toneau, the rear seat arm rests are attached to the outside sides of the toneau wood.  These also get 4 durable dot snap bases on each armrest side to hold the gypsy curtains.

The wood used on the toneau surround is typically a semi soft wood (not oak) Mahogany, birch or poplar.  Easy to carve and accepts tacks easily without splitting.   

On this car I was given mahogany wood, but it needed to be modified to fit the car better.  The outer side of this wood is recessed from the edge of the body sheetmetal by 3/16”.  This provides some room on the sides for the armrest leather, trim, and snaps.  On the back side, the back curtain canvas will stop on this metal edge.  The set back of the wood lets the canvas sit even with the back of the sheetmetal with a very small amount of being flush or just a little proud of the sheetmetal.   About fifteen  #8 x 1 ½” countersunk screws hold the wood to the rear tub.

The person that carved this rear wood originally made it a fit flush with the edge of the sheetmetal.  That is too wide, so I had to shorten it in the middle (photo left).  I also had to fit it more evenly across the back.

The next missing item are the top rear strap supports.  You can use this drawing as a guide to determine the location of the strap loops.  On the back of this car the holes were drilled for the brackets to be 37” apart, but I had no brackets. 

I need to make the strap loops.  As a side note, I also thought that I could have used “Footsman loops” and some long wood screws, but I built these brackets as Buick did. 

I used 1/8” steel plate.  I bought a piece of steel 3” x 12” on Ebay.  First I made the U shaped bracket that goes over the wood.  I cut it on the bandsaw and folded it over some scrap metal.  I did have to carve out the wood so that the metal is recessed into the wood.

Next I made the straps ends.  Making the slot is a pain because I do not have a mill.  5 holes in a row and then lifting the plate steel on the drill press to break the steel between the holes.  Then I filed it smooth.

Then I was able to set it on the back wood, but I still need to paint it.  Now I have brackets to hold the rear top straps.

 

 

 

Edited September 20, 2023 by Hubert_25-25 (see edit history)

[EmTee]

Puzzles are definitely more challenging when a few pieces are missing! 

[Hubert_25-25]

Time to clean up the top sockets.  No dents to deal with and no rust in this set of top sockets.  Unusually in great shape.  Choices on removal of the paint is sandblasting and then dealing with excess sand, and taking it 30 minutes one way somewhere, or using the wire cup wheel on an angle grinder seemed to be the easiest method that removed the paint the best, but it took one person to hold the sockets and the other to run the angle grinder with the cup wheel.  Also used a wire brush, 40 grit sandpaper and a pick.  Time wise, I think it was a wash and I might have preferred taking them somewhere and drinking lemonade instead.  Wear a mask as paint removal is always a dirty job.  As you can see they did clean up nicely.

Then it was a choice to paint or powdercoat.  Powder coater is 1 hour away.  I also had a concern about the wood coming out from inside the sockets if the sockets spend too much time in the oven.  If you do powder coat, it has to be someone you trust, and they have to minimize oven time.  I finally decided to use 2K primer and single stage acrylic enamel automotive paint.  Know what else I learned?  Paint has gotten massively expensive in 3 years.  A gallon of Transtar 2K primer went from $116 to $200.  A quart of Nasons black single stage acrylic enamel is now $120.  Nason is the less expensive division of Dupont paints.  Then I looked up Chromaclear 7900S clearcoat, and it is now $436 a gallon and the quart of activator is $137.  For you painters, I switched to Nasons Select clear and saw no difference to chromaclear.  It is $150 a gallon and the activator is $75 a quart.    

   So I put up the tarps and plugged in the air compressor.  It ran for a little while, made a strange noise, then tripped the circuit breaker.  Good thing I had the pancake air compressor as back up.  It worked fine for the top sockets.  I will admit that I don't like to paint small rods like this, as it is more wasteful of paint than doing car panels.  Still it does the job.  I do have to go back and brush touch up all the joints as it is best to paint these top sockets in the nearly open position, but then you have to go back and touch up the small spots at the joints.  The small top sockets in the background are for a 1910 Metz that I am putting a top on.   

 

Edited September 24, 2023 by Hubert_25-25 (see edit history)

[EmTee]

7 hours ago, Hubert_25-25 said:

Powder coater is 1 hour away.  I also had a concern about the wood coming out from inside the sockets if the sockets spend too much time in the oven.

 

I wonder whether coating thickness/build-up would also be a concern with powder coating, particularly at the joints.  Then, there's the touch-up problem as well.  Seems like paint is the right choice.  The material price hike is ridiculous, however.  Lately I find myself falling back into my 1980s habit of not delaying purchases any longer than necessary in an attempt to get ahead of increasing prices...

[Hubert_25-25]

Just a few comments to address Emtee's notes.  I did powdercoat the sockets on my 1925 Buick.  Very durable and it did not effect the folding operation.  I did do some powder coat friendly filler in some dents, but the powder coat guy blasted that off, so they did not come out as smooth as I would have liked.  I did not need to do any touch up, as the powder coating got in all the tight spaces.  Touch up is easy with paint.  So it's kind of a wash either way, powder coat or paint.  

 

This next step seems like a simple step, but it got complicated finding old school caulk.  The tonneau wood is recessed just slightly from the back face of the sheetmetal.  The top material stops on the top edge of the sheetmetal.  If any water were to sit on the top side of the sheetmetal, it has a 50% chance of getting into the car or runnning outside the sheetmetal.  So I wanted to caulk the wood against the paint. 

I did not want to use silicone because if it ever has to be removed, it could remove the paint.

I tried using 3M strip caulk, but it is rather messy and takes too long to apply. 

I ended up using good old latex caulk.  It is actually getting harder to find because so many caulks contain silicone or another adhesive, and I do not want an adhesive.  Plus it's $3.00 a tube.  It should seal out any water, and it won't adhere to the paint.  

So the back mounting on the car is complete.  I now have to weld the top header clamps together so moving on to getting missing fasteners for the front bow.  

Edited September 27, 2023 by Hubert_25-25 (see edit history)

[Mark Kikta]

As always, nice work Hugh!

[KEK]

Hugh-

 

Thanks for sharing all your hard work.  This is great information and inspires me to some day put the top on my 25-24!

[32buick67]

@Hubert_25-25 you blow my mind!

I always hold you ChemEs in high regard, amazing brains and abilities...make us EEs look like chumps.

Your skills and knowledge and problem-solving methods are impeccably impressive.

You might be like me and probably don't sleep much, life is too short to sleep, too many interesting and curious things to explore, and I have to admit that this didactic post topic is captivating.

I thought resolving Marvel venturis was interesting, but top bow geometry and function and evolution has opened up a whole new world of interesting discussion.

 

FWIW, I enjoy the high profile folds vs the more modern compressed folds (modern as if the designers were trying to hide the folds).

To me, there is just something about seeing a big 20s car with the folded bows sitting high and proud above the passenger heads.

 

Nicely done in helping recover what would have been a stalled project.

Hopefully you are having fun doing and learning!

Mario

[Hubert_25-25]

Thank you for the kind posts.  I have always found convertible tops to be magical in that a lot of the details have to be just right to get everything to operate as it should.  I am finding that close can get you where you want to go regarding having a "functioning top", and although "not perfect" is far better than "no top".  And if you have to make the fabric portion anyway, because there is no pre made top available, corrections can be made to make it come out right. 

So now I do not have the front bow clamps, so I had to make a set.  I used a 1/2" heavy hex coupling nut.  I had to anneal it as it was grade 5.  Heated it red hot then let it air cool.  Too hard to drill, cut, and tap otherwise.  The side hole was 5/16-18 tapped just to make it easier to hold the nut so that it could be welded.  I bought a scrap of 3/16" x 1" x 12" steel on Ebay.  This was cut and everything welded together.  Then it was bent and painted.  A slight difference between the Master and Standard clamps.  First drawing from Larry DiBarry.  I also had to make some additional minor bends due to the windshield uprights being off slighlty.  The clamp screws are modified Model A screws.   Put in the bandsaw and filed to a point.  

Now is a good time to also compliment Larry DiBarry and Kevin Roner.  I have had several parts that I had spent hours searching for.  They taught me how to make facimilles and that moved me along where the part either stayed, or I was able to find a replacement - but I was able to keep moving getting the car put together.  

Hugh

 

    

 

[Hubert_25-25]

Now the work begins.  Buick used a metal "visor" to provide a seal between the windshield and the top.  This is a 4" wide piece of sheetmetal.  It has to be shaped and a "48" brake can be used, or it can be done by hand with several clamps and wood and a couple of pieces of angle iron.  I had to do this using a clamp as a metal brake is not close to the car.

The front bow is curved on the edges.  The visor provides a flat front and a metal top above the windshield to provide a good water seal. 

This is what the visor looks like.  It may need to be adjusted to fit your vehicle

First a 4" wide cardboard sheet is used to check the flat (x and Y) dimensions for the sheetmetal.   This is used as a template to cut the sheetmetal.

Next a 4" x 4" piece of sheetmetal is used to be bent and determine the shape of the visor. 

This will get some padding between the metal and the windshield and then a canvas covering.

This is the water seal area.

One thing I needed space for is the windshield wiper.   The first 90 degree bend needs to be far enough from the windshield so that the wiper does not interfere. 

You will see later where I had to do more modifications to the sheetmetal to get the wiper to fit. 

Notice how it is running into the wiper. 

First the metal is bent into a "90".  

Then the metal is rolled to make an S shape in cross section. 

This photo shows the roll is set back 3/4", but that was too far back.  

I should have rolled this with a smaller piece of pipe, but you get the idea.

I used a pry bar to bend the metal in increments along the length.

 

Now the issue is that I need to deal with the wiper arm. 

So I used a ball peen hammer and moved the first bend line toward the front of the car in the wiper area.

This is the visor in place.  It will get padding and a canvas covering.  

  

So the good news is that now I am able to assemble the wood bows into the freshly painted sockets and install all this hardware on the car.  

There may be other ways to provide this seal.  This method does seem to do a good job, but it takes some effort to get it right.

I am now finally ready to start cutting some fabric. 

I do need to put the back window in order so I will provide some updates on that as well.

   Hugh

Edited October 11, 2023 by Hubert_25-25 (see edit history)

[EmTee]

It's clear to me that you can see the finished product in your head.  Great work and this is certainly a big milestone in the process! 

[BuickTom87]

The ability and knowledge to do this is incredible!! I wish I had the skills and patience to do this 

[Mark Kikta]

Nice work Hugh!

[Hubert_25-25]

This posting is multipurposed.  I also want to explain a little about top socket geometry.  This car came to me with two sets of top sockets.  The photo below is the socket assembly that I believe is likely from an earlier Buick, but could also be repurposed to another car.  There are lots of "Orphan cars" a term given to so many early makes of cars where the manufacturer is no longer in business.   Maybe this would fit a Packard, or a Moon, or a Pierce Arrow?  I would love to find a new owner for this set which is in excellent condition.  

The first thing when looking for top sockets is to have the seller open them as photo 1 shows below.  Take a few dimensions, and then the long section needs to be made level.  The mounting eyelet center is set against a straight piece of wood.  The mesurement is to just touching the underside of this long frame section. 

In this case, the long section is 26 3/4" from the wood at the front and the back of the top frame assembly. 

       Photo 2 shows this cars height from the top of the door to the base of the windshield top clamp to be 19" .     

The socket assembly line of that long top frame section should run parallel with the top of the doors.  So I am looking for a car needing a top assembly where the top of the windshield to the doors dimension is around 26 to 27 inches.  As you can see that for this Buick, the top frame is too tall for this car.  This goes on a car where the windshield is about 8" taller!  The earlier models had taller windshields, so maybe this will go to a good home one day.   

 

One last note. This level section of frame attaches to socket #4.  Later models attach the long section to socket #3.  For that style of top frame, refer to the earlier posting in this article for how to analyze those style of top frames.  

Hugh

Edited October 12, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

Moving along onto the front bow.  The straight center section is covered with stayfast to the middle of the top clamps.  Then the two side sections are covered with fabric oriented at a 45 degree bias.  These overlap the center section covering by extending to the inside of the top clamps.  The outer ends are folded under to cover the end of the top sockets by 3/8".  ALWAYS START FROM THE MIDDLE OF EACH PIECE AND WORK OUTWARD.  All staples are on the top side of the front bow.  A single 1/2" tack is used on the end for security.  Many times the front bow is covered in lightweight bowdrill, but I like using Stayfast to give the wood extra water protection and the stayfast is more durable.    (Photo 1)

 

Now the top is folded to install the sheetmetal "Visor".   The fabric cut is 10" wide and 3" longer than the visor.  It is stapled (stainless) to the bottom side of the front bow.  The visor is attached with ten #6 screws.  An ice pick is used to locate the threaded holes created earlier.  1" x 1 1/2" Dacron is used for the windshield seal.  Contact spray is used to hold it to the visor sheetmetal.  The stayfast edges are folded in to encapsulate the sheetmetal.  The end of the stayfast is then pulled up onto the front of the top bow and stapled high in the front bow face.  This prevents these staples from interfering with other staples that will be placed later. This makes a waterproof cushioned seal for the front sindshield.  (remaining photos)     

 

[Hubert_25-25]

Upholsters really knew how a little fabric can dress up a top.  The cloth that covers the wood bows is called "bowdrill".  It is very time consuming to cover the wood bows and keep all the wrinkles out, and go around corners in the process.  The bowdrill fabric is laid out as close to a 45degree as you can get.  Using newspaper for patterns, I made 3 strips 12" wide x 75" long.  This is bias cut.  It helps the fabric fold around the corners.  On the bows I used a strip of 1/4" basting tape (double sided tape).  I put this down the center of the bow.  I started in the middle and worked outward.  I used a straight needle and a whip stitch that made a slight pull on the fabric to tighten it up on each wrap.  There is a fold over on the top side of the fabric to hide the cut edge.  The needle worked better going in the single fabric and out the folded over side.  I also tried to set the basting tape out of the way because if you go thru it, the needle gets gummy after a while.  Bows 2 and 3 are best sewn because there is a small flat spot on the top side of the bows, and sewing hides the seam better than using tacks or staples.  Bow 4 is stapled as all the staples are hidden.   All the bows are covered now and I am excited to be able to move on to tensioning the top and making the pads.  It is a lot of hand sewing.  I was glad that Mark Kikta is doing his top now as it gives me someone to compare notes with.

Hugh   

 

Edited October 20, 2023 by Hubert_25-25 (see edit history)

[dibarlaw]

Hugh:

 It looks like I will have to redo the bowdrill on my Master since all they did was tack the seam on the top of  the bow. Those nail heads from 1980 are wearing into the inner linining of the top material.

[Hubert_25-25]

Larry,  

    Sewing the bowdrill is a best practice.  Tacks can create a lot of problems.  The bowdrill on Mark Kikta's 1922 Buick OEM top was sewn.

 

Now I get to make the pads.  I have seen bowdrill used as the covering, then 3 Jute upholstery straps per side, then cotton padding on top, then hand sew it down the center.  Job done. 

David Coco showed me a better way.   It uses top material under the pad.  The top stitched seams should be over the pads.  This should prevent any staining if there were any top seam leaks.  Using Stayfast makes a more durable pad and adds a little more strength to the webbing. 

Here an 18" x 100" piece of 4 mil poly or "duraskrim" is tacked where the pads go.  The 2 outer webbing straps are set 8" apart on the ends.  The straps are pulled tight and tacked with 2 tacks each on each end.  A fine point marks a lot traces the outside edge of each strap. 

      

Everything is removed.  A piece of stayfast 4" wider than the pattern is cut.  This is now placed on the car, and the process repeated.   I also ran string lines just to ensure the outer lines were straight.  I also used some temporary tape to locate on each bow where the string ran across to ensure the pad is installed in the correct location.  Again, we mark the string lines on the stayfast with the fine point pen (I used a silver marks a lot).

 

The stayfast is now marked at 1" outside from the string lines.  This is the cut line.  Notice how the lines are not straight.  Cut this out and make a mirror image piece for the opposite side.

Measure the widest distance across the stayfast material.  Mine is 11”.  Divide this by 2, and add 3”.  So I need to cut four pieces of bowdrill 9” x 100”.   Stack two of these bowdrill pieces and insert a row of straight pins 2” from the edge.  The pins must be inserted parallel to the long edge.       

-          Unfold and lay the bowdrill flat on the table.  (Top side up)

-          Place the stayfast (top side up) on top of the two bowdrill pieces. 

-          Adjust the stayfast fabric so that the row of pins is down the center of the stayfast fabric.

-          Draw the outline of the stayfast onto the bowdrill.  This is the cut line.

-          Cut off the excess bowdrill.

-          Reverse the stack.  On the table place the stayfast (interior side down). Then the bowdrill covering on top.

-          Slide the bowdrill to be ½” from the stayfast edge. 

-          Fold this ½” stayfast edge over the top of the bowdrill and clip (or straight pin) along the length.

-          Sew each side length.

Tack the 4 corners of each pad covering to bows 1 and 4.  Tack the webbing to the upper half of the front bow.  Four 1/2" tacks per webbing on the upper half of the front wood bow.  Two tacks on the top side of each strap very near the front wood edge.    

Pull tension on the stayfast and the webbing at the rear.  Tack in the upper half of the rear bow.   2 tacks per strap on the top side near the edge of the wood.  Add 4 to 5 tacks on the top center of bows 2 and 3.  Add the padding.  Close the top of the padding bowdrill with straight pins.   Trim the excess material to leave the bottom half of the face of bows 1 and 4 clear.

Stitch the length using a 2" whip stitch.

  

Now I can get to work on the actual top fabric and getting the rear window in order.       Hugh

 

 

 

Edited October 26, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

Back at it after not posting for a while.  Sorry.  So the trick is adding 3/16" strings where the seams will go.  Not sure?  Ask someone who has your top.  On the top side, they are 44" wide at the front and 48" at the back.  You have to do the same thing with the rear curtain.   I do make the width different at the top of the back curtain so that the seams do not lay on each other, so these are 44" at the bottom and 47" at the top.  The seam strings are held on the ends with thumb tacks.  Then they are pulled tight.  Then they are temporarily stitched to the pads about every 8 inches with a whip stitch.  Then I use a marks a lot every 8 inches - but I also mark every high or low point.  Plastic is stretched over the center roof section and pulled tight.  The plastic is marked on the top side of the string, and then the plastic needs to be 2" wider on each side of these 2 strings.  This is the pattern for the center piece of fabric.

For the side panels, the plastic is only a pattern, so we only need to do one side.  The outer side needs to be hung without wrinkles, and the plastic by the string needs to touch the string.  In photo 2, I have a string pulled that is 1/2 lower than the front bow, and runs parallel to the top of the doors to the back.  IT IS ALSO 1/2" BELOW THE FRAMES LOWEST POINT.

I have also added a detail piece made of cardboard so that I can mimic the top design used by Buick in 1925 thru 1927.   (This is how you could tell a Buick from one that was made in 1924). 

The plastic patterns are only used to get close in cutting a piece of fabric that is close in size so that you do not waste fabric. 

The third photo shows you how I do not let the top seam and the back curtain seams overlap at the same place on the back bow.      

The back curtain is similar to the top, so I will just show the top process for now.  The center section of fabric (cut from the pattern) is stretched.  Soap stone is used to mark where that 3/16 cord is under the top material.  Mark the top using 2 fingers to push down on either side of the string while tracing it.  You also need to mark all those 8" spaced string marks, and the high and low marks on the fabric where the string is.  Then take off the center section and do the same with each side panel.  Each side panel should basically touch the string, and hang down straight on the sides at the elevation of the side string.  Put those same marks on the side panels that you did on the top.  Now pull off the side panels. 

Use a compass to add 5/8" to the string line on each panel.  Cut off the excess.  Place the panels face to face and match those string marks on the 3 panels.  Use clips to hold the fabric together.  Stitch the main seam.  Lay the fabric over, and stitch the visible seam.  This gives you the untrimmed  top panel that you see in photo 5.            

[Hubert_25-25]

Now we will mark the side panels after pulling the top tight again.  I have moved the straight line that was behind the plastic, to the outside of the fabric.  I have also added my cardboard trim detail.  I use a scrap piece of 1/8" x 1" x 6' aluminum to help with marking this line on the side.  I also use the soapstone to trace around the cardboard template.  So this soapstone marking is the finished edge.  When I lay the fabric on the work table I will use the compass and add 1/2".  The 1/2" extra is the cut line.  

I have added a roughly 2 1/2" wide reinforcing strip on this outer edge.  Then the 1/2" extra on the edge is folded over and clipped.  I am still using black for both bobbin and on the machine.  I will sew this with the 1/2" side on the top side. 

We will add the inner reinforcing stitch after the back curtain is sewn.     

d add 1/2" 

 

Edited November 8, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

The back curtain is similar to the top.  Same string used for the seams, 3 panels.  Hidem is used across the back at the base, so the base of the center panel is marked with soap stone at the wood and metal interface.  We will add 1/2" to this with a compass for a cut line.  On the sides, we again use soapstone to mark the wood to metal interface, but we will add 1" using a compass for the cut line.  This is because here the gypsy panels have snaps and the fabric overlaps the metal tub.  Note also that the hidem stops at the top rest rods, so a transition has to be made just forward of the top rest pins.  On the top side of the last metal socket, I used a scrap piece of 1 x 2 and soap stone to mark where the top side of the socket is.  On this line, I will add 1/2".  I also made the ends of the gypsy curtains curve like the factory photo showed.   Photo 3 shows one side sewn with the reinforcing in place, and the other side ready to be sewn.   Note that I stop short of the inner back curtain, as I am just wanting to sew the gypsy curtains first.  

Photo 4 shows the inner back curtain.  This was bowdrill, but I find bowdrill to not be very durable.  I like to make the inner back curtain out of top material.   I have also seen staining on the inner back curtain, and if the back window is done right, maybe this wont stain as well.  Notice how the inner back curtain is 1 1/2" wider on each side than the back curtain seams.  Like the roof pads, this hides the back curtain seams.  

Last 2 photos.  Now I can sew the inner reinforcing stitch.  Up until now, all of the sewing has been using black thread on the bobbin and in the machine.  Now I switch to tan thread on the machine side, but stay with a black thread on the bobbin.  I use a compass to set the inner stitch at 1 3/4".  2" is good too.  I stitch this line sewing with the inside side up, and then trim it 1/8" to 3/16" from the stitch.  I stitch the top and the back curtain.  The back panel is now ready for one more fitting on the car for the snaps, and installation of the rear window.

Edited November 8, 2023 by Hubert_25-25 (see edit history)

[Fordy]

Absolutely fantastic that this process is being shared. I am sending a link to this thread to a mate who will have to tackle that job soon.

Thanks Hugh

Regards

Steve

[EmTee]

I can't help but wonder how these tops were made in quantity originally.  Were they done in an 'assembly line' fashion, with individuals making copies of a particular piece of the puzzle that were assembled and sewn into the final top by a team - or was each top made by a single person?  Cost to produce these tops must have also been a factor that drove car companies toward all-steel closed car bodies...

[Hubert_25-25]

No one ever shows how they make corrections, and I learned a lot about sewing from my mother, but when I sewed up the back curtain, I left out the two jute straps that hold the base of the back window.   So this is the tool and how I back added these straps. 

First I marked the location for the straps and went 1/4" wider on each side so I could slide them in.  This little tool is called a "Seam Ripper".  Use the point and break the stitch on both sides.  Continue to use the point and pull each stitch away from the break, working one stitch at a time.  When you get to where you want to stop, you can pull both threads to either side of the fabric.  My choice is to tie the two threads together on the inside of the top (behind the back seat).  So I have 4 knots per strap.  I slid the strap in and used 3 clips to hold the strap and the folded end.  I sewed back over my original stitch lines.  Normally to start and stop a machine stitch, you put the machine in reverse for 3-5 stitches, then go forward again.  I did that on the bottom stitch , but on the upper stitch, I just started where I left off.  Then I went back and used the seam ripper tool to pull both ends to the inside and hand tied the end. 

In the last two photos, you can see the inside and the outside of both stitches.  Normally it is even more invisible if both threads are the same color.         Hugh   

 

Edited November 8, 2023 by Hubert_25-25 (see edit history)

[Hubert_25-25]

Yesterday I worked on installing all the fasteners on the side curtains. At the base pivot of the last top socket, I had to drill and tap a #8-32 on each side as Buick used a double "lift the dot" in this location.  One for the rear curtain, and one for the side curtains.  Next I had to mark the locations of the studs on the wood armrest and the last top sockets.  These are measured for mostly equal spacing.  I drilled a 1/8" holes in the center of all locations.  Then I used push pin tacks to stretch and locate all the snap centers.  I marked the pin marks in the fabric and punched all the holes with an adjustable punch.  I set the "durable dot" fasteners on the die tool and set all the snaps. 

In the last photo, you can see the single "lift the dot" fastener at the tip of the gypsy curtain.  The last snap at the top of the gypsy curtain is a "gypsy snap".  Instead of a button head, this is a male stud head.  The button head is on the back corner of the top panel, so this makes a go between snap.           Hugh 

[Hubert_25-25]

2 posting tonight (see above), as today I installed the back window in the back curtain.  But there is prework that I did not show earlier.  This is an original Buick Johnston window.   When I did separate the frame, the original basswood frame came apart in 8 pieces.  I first sealed all the wood pieces with epoxy sealer, then I used 2 part Epoxy to glue it together and then 2 part epoxy with Q cells to fill the holes so that it would accept tacks.  I put foil between the metal and the frame for alignment of the holes and to prevent the two parts from sticking together. These normally take 18 screws, but one hole came apart, so I had to fix it with JB Weld and install a stud and add a nut. 

The frame was almost black from oxidation.  I had to hand sand it to remove the oxidation, then I polished it and clear coated it. 

Rebuilding this old frame was an entire work process in itself.

 

Now on to the the window installation.  I made this drawing several years ago to help with understanding how the back windows are installed. 

I started with locating the wood backing onto the back curtain.  Next, I put down tape underneath where the holes are.  I used a small pen to mark the locations.  I used the adjustable punch for the holes. Then I assembled the 2 frame halves together with the stayfast between.  After all the screws were tight, I was able to trim the edge of the back curtain fabric even with the inside edge of the metal frame.  Then I installed the webbing support straps. 

Next I pulled the inner back curtain in place and began trimming.  I traced the inner edge of the wood frame with soap stone, then used a compass at 1" to rough cut out the hole.  I used a putty knife and pencil to mark the cut line of the inner back curtain.   The inner back curtain is stapled to the inside of the wood frame.  

To set the glass, a bead of clear silicone is put on the glass side of the stayfast that is against the metal frame. 

The glass is set in the silicone.  

 

 

To hold the glass, I used three pieces of .050 polyethylene cut 3/8" wide.  These are 5 feet long.  I used 2 strips of basting tape and a 1 1/2" wide piece of bowdrill cut on a bias.  My staple gun also shoots 5/8" brads, so these are used to hold the glass in place.  I shot brads every 2 inches.   I used a piece of cardboard to protect the glass.  Last 2 Photos are of the back window inside and out.     

To address EmTee's comment, a new last picture.  A back curtain was available - with or without the back window from the Buick dealer.  I assume they had stacks of back curtain assemblies, and stacks of top sections.  On the assembly line they likely only had tacks and a tack hammer.   All the sewing was likely done in some other sweat shop.    

Hugh

 

 

   

Edited November 10, 2023 by Hubert_25-25 (see edit history)