'15-'16 Top Bow Dimensions

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MWalker
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'15-'16 Top Bow Dimensions

Post by MWalker » Sat Aug 22, 2020 8:19 am

I need to know how far the top bows extend above the sockets for a Roadster. I did a google search for the info I need but didn't come up with anything concrete. There is a drawing which has been posted many times which gives the total length for the socket plus bow (32-7/8") for the middle bow, but not the front or rear ones. Does anyone have that info in your notes? Thanks.


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Re: '15-'16 Top Bow Dimensions

Post by MWalker » Sat Aug 22, 2020 3:02 pm

Anyone have this info?

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Re: '15-'16 Top Bow Dimensions

Post by DanTreace » Sat Aug 22, 2020 3:13 pm

Mike

Only have this info gleaned off the forums past. Nothing specific have seen on the '15-'16, but this may help you.


’17 Roadster round/ oval socket iron
Bows are 47 1/2” wide. Front #1 bow protrudes 7 ½” from iron, Middle #2 protrudes 7” and Rear #3 protrudes 8 ½”


’13 – ’14 Touring Most are similar, some vary
Wood bows 53” wide. Front #1 bow protrudes 7” from the iron, # 2 protrudes 9” #3 protrudes 6 ½” and Rear #4 protrudes 6 ¾”
The best way is always the simplest. The attics of the world are cluttered up with complicated failures. Henry Ford
Don’t find fault, find a remedy; anybody can complain. Henry Ford


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Re: '15-'16 Top Bow Dimensions

Post by R.V.Anderson » Sat Aug 22, 2020 6:37 pm

Mike, on the 1913 roadster, the amount the wood is driven into the sockets (Ford called it the "drive", logically enough) is 6" all the way around; front, upright, and rear. I believe the 1917 oval sockets would be the same. Hope this helps.


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Re: '15-'16 Top Bow Dimensions

Post by MWalker » Sat Aug 22, 2020 8:53 pm

Thanks for the help, guys. I'll attack them tomorrow.

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Re: '15-'16 Top Bow Dimensions

Post by Hap_Tucker » Sat Aug 22, 2020 9:02 pm

Mike,

John Regan posted some detailed information on the 1915 runabout top at: http://www.mtfca.com/discus/messages/29/23098.html I have reposted that here: While he does not share how far the wood bow goes into the top socket, he shares lots of other details there.

++++++++++++++++++ John Regan's post is below +++++++++++++++++

By John F. Regan on Sunday, January 07, 2007 - 04:13 pm:
Clarance:

The following dimensions taken from FACTORY DRAWINGS of 1915 Roadster top:

Front bow:

Center of iron pivot point to INSIDE front wood surface of front bow is 26-1/2". This is measured along the iron which is of course sitting at an angle. The bottom most edge of that front bow wood should be in front of the windshield and sitting 1/4" lower than the very top most edge of the windshield tubing and if all is correct then that same bottom edge of the front bow should be sitting 3-3/16 in front of the front edge of the windshield tubing.

Center Bow:

Center of Body iron Pivot point to bottom most flat surface of center bow is 32".

Rear Bow:

Center of rear bow iron pivot point (where is joins the center bow iron) to bottom surface of rear bow is 34-3/4" That rearmost bow wood edge sits 3-1/2 behind seat rearmost edge. To confirm that location further - the rearmost edge of the rear bow should be 29-7/8 above the center top iron body pivot point (not the rear bow pivot point). The bows are 7/8 thick typically and thus the topmost surface of the center bow should end up 3" taller than the rearmost edge of the rear bow. Since bows are rectangular in cross section. Each of my dimensions calls out the correct EDGE of that rectangle if it is sitting as it should be since then angled bows have a topmost edge, bottom -most edge, front most edge, and rear most edge.

Front bow is DIFFERENT than the other 2 bows. The bows typically have a slight crown in the center. The front bow is different in that it has a larger RADIUS than the other 3 bows. Typicaly repro bows are a set of 3 with ALL alike so you will need to take that into consideration when trying to fit the front bow. Because the front bow is sitting almost horizontal then it is intuitive to me that the front bow needs a larger radius at the corners so that the curvature of the top material will then match the shorter radius of the next 2 bows. Placing a bow at an angle essentially makes its radius to the sides much smaller and that is the reason that original tops fit better at the front than repro in my estimation.

To PRE-ANSWER a question - NO I will not provide a copy of the factory drawings to anyone. This is simply because as an engineer I respect the intellectual property rights of the Henry Ford Museum to these documents and have signed an agreement there to NOT copy their documents. To provide copies would endanger my agreement with them that I signed and they could bar me from further research there and that would be a catastrophy for me since I love to research.

+++++++++++++++++++++++ end of John's posting ref dimensions of the roadster top ++++++++

You mentioned the illustration below by Murray Fahnestock that has been posted several times:
two man top 1915-1922 roadster.jpg
If you know someone that is good with trigonometry/math -- they should be able to tell you the length from the center of the upright to the front of the front bow and the same for the rear bow. With the distance of two sides known and the 90 degree angle it was easy for me to figure that out about 50 years ago. But not so much today.

However, if you mock up the top sockets, with the bows, with the car -- you should be able to mark a good starting place for how far the top bow should go into the top socket and have the dimension which are given in Fahnestock's illustration come out correct. Then you can work the top bows and fine tune the measurements with the top bows inserted into the top sockets.

How to mock it up? See Bob Cascisa's method at: http://www.mtfca.com/discus/messages/80257/93079.html and the photo of how he did it is shown below:
Bob Cascisa.jpg
That takes a lot of clamps -- and you may need to use string to tie the uncut bows to the side of the top sockets. There will be some adjusting to get it correct. Good news -- you are working with a roadster so doing the front and then the back -- the center top socket stays vertical.

And if the body was rewooded, be sure the pivot point is correct -- again you have seen this illustration before:
1915-1923 wk Roadster body dimensions.jpg

Hopefully one of the folks with a 1915-1917 oval socket roadster will give you some additional measurements.


Respectfully submitted,

Hap l9l5 cut off


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Re: '15-'16 Top Bow Dimensions

Post by MWalker » Sun Aug 23, 2020 10:03 am

Hap -- Thank you for your post. There is lots of good information in it, as is the case with all of your posts. John R. gives the overall lengths of each iron + bow, so it's easy for me to ascertain the point at which I need to fit the bow into the socket. And thanks for the link to Bob C's very informative thread. I did woodwork for 40 years+, so I have lots of clamps. :) I now feel confident in moving forward with the rest of the work.

Thanks to all for your help.

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Re: '15-'16 Top Bow Dimensions

Post by Hap_Tucker » Sun Aug 23, 2020 8:54 pm

Mike,

I'm glad you have enough information to proceed. I love the saying that none of us is as smart as all of us put together. Also, please take pictures and let us know what worked well and what didn't work so well. And please add your findings/experience.

One other item I ran across was a photo of the 1915-16 roadster top sockets by Leon Parker. That information is at: http://www.mtfca.com/discus/messages/25 ... 1341620611 You may want to take a look and confirm that your bows are similar to those photos. The posting shares that the 1913-14 top sockets are similar. But it indicates that the 1913-1914 front top socket is longer than the 1915-1917 front top socket.


And if you didn't see the one at: http://www.mtfca.com/discus/messages/17 ... 1320526950 it has a good illustration of fitting the bows into the oval sockets. And another one on an earlier car at: http://www.mtfca.com/discus/messages/29 ... 1205772092

And the Tulsa Tech Page has info on fitting a 1913 Roadster top that may be of interest. See: http://mtfctulsa.com/Tech/roadster_top.htm

Good luck with your project.

Respectfully submitted,

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Re: '15-'16 Top Bow Dimensions

Post by MWalker » Wed Aug 26, 2020 3:48 pm

Armed with the numbers in John Regan's post, I forged ahead. Since his numbers are to the bottom face of the bows, I clamped a 4' level even with that edge to use in making my measurements. That worked quite well.
DSCN5095.JPG
I thought I had taken a pic of a finished fitted end, but now I can't find it. Oh well, you've all seen those anyway. I used a small router with a 3/16" roundover bit to get rid of all the sharp edges on the bows. Here are the three bows fitted to the sockets. I gave them a coat of spar urethane for protection after this pic was taken. I delivered the car to the upholstery shop yesterday.
DSCN5094.JPG
These are the tools I used to do the fitting of the ends, a draw knife and spokeshave.
DSCN5096.JPG
I used these and other hand tools for working wood quite a bit back in a former lifetime. That was many years ago, and I haven't done much woodwork since then. It felt good to be working on these bows while standing in a pile of shavings underfoot. :)

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Re: '15-'16 Top Bow Dimensions

Post by KWTownsend » Fri Aug 28, 2020 12:10 am

Nice work, Mr. Walker.
Looks good!

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Re: '15-'16 Top Bow Dimensions

Post by Hap_Tucker » Fri Aug 28, 2020 8:09 am

Mike,

They look great! And you draw knife and spoke shaver remind me of the ones my Dad had and that he gave to me.

Question if you have time, Dan Treace had posted some measurements (thank you Dan) saying how far into the top sockets the ends of the bows went. Did you find that using John Regan's total measurements resulted in the ends of your bows being in the top sockets the same or similar amount as what Dan found and posted? I would think there would be some variation based on who did the original bows? One person might make the bows longer and another person might make them shorter? I would guess that John's measurements would work well regardless if the bows were made longer or shorter since they gave the overall distance/height/fitting from windshield etc.

DanTreace wrote:
Sat Aug 22, 2020 3:13 pm
Mike

Only have this info gleaned off the forums past. Nothing specific have seen on the '15-'16, but this may help you.


’17 Roadster round/ oval socket iron
Bows are 47 1/2” wide. Front #1 bow protrudes 7 ½” from iron, Middle #2 protrudes 7” and Rear #3 protrudes 8 ½”

And great work on the top bows!

Respectfully submitted,

Hap l9l5


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Re: '15-'16 Top Bow Dimensions

Post by MWalker » Sat Aug 29, 2020 9:53 am

Hap -- The bows I got years ago from Jim Finney had plenty of length to cut some off. I cut about 6 or so inches off each end. The sockets I used were new ones from John Boorinakis. John puts some type of epoxy or something in the sockets, so the level of that is what determines how far the bow wood can extend into each socket. Mine varied slightly, but each had somewhere around 4-3/4" of depth. I cut my bows accordingly. Ford put wood into the sockets instead of epoxy. I know that because the old sockets I had had gotten water into them at some time and the resulting swollen wood burst the seams on the sockets. John had me send him my old sockets, and he used all the cast parts of those and put them onto new tubes.

Maybe Ford left a specific amount of space in the sockets for the bow wood; I don't know. But it's easy to put the end of a measuring tape into each socket to determine how much depth is available. The amount of wood which goes into the sockets is irrelevant. The important numbers are how far the wood extends above each socket so the top is the correct height. Some references above mention 6-1/2", 7", etc. Those numbers were close, but not necessarily correct. The numbers from John Regan which were the distance from the pivot point of each socket to the top or bottom face of the bow at the top were the ones I used, and they worked fine.

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Re: '15-'16 Top Bow Dimensions

Post by Hap_Tucker » Sat Aug 29, 2020 1:59 pm

Mike,

Thanks so much! Following the dimension that John Regan shared sounds like a good way to go. (Disclaimer -- if someone is really tall -- or tall in seating height -- they may want to add a little extra room....) Being height challenged, I don't have to worry about that but both of my son-in-laws are tall guys.

Again great looking work and thank you for the additional details.

Respectfully submitted,

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