my DIY convertible frame

my car came with the basic two hoop convertible frame.

i couldn't get it to fit snug, so i cut it an welded in two turn-buckles on each side (4 in total).

worked pretty good but looked pretty half-assed IMO

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now that i am itching for some fabrication-work to keep my hands busy - i decided to build my own scissor frame. but with just pictures, it was too tricky, so i bought one from Mexico. it came (i think it took ~1.5 months to arrive.

i did this to save time, but i was not thrilled with the fit or quality. i guess i have high expectations.

so i cut and welded two round turn buckles in the middle of each bow.

It fit better, but i wanted it to fit like a glove and that would require more fabrication.

at this point, i decided to start with my own design and make one to my standards, but use the one i have as a working example.

really take my time and make it look sweet - you know

...

anyway - here are the pics of the frame i bought:










can't find any pictures with the buckles welded in - so you'll need to believe me.

also - i'll be documenting the same pictures on my website:
http://www.mangosmoothie.ca/convertible-frame

so, first step was to fabricate the main mounts.

buy some metal stock (3/8" wide) - not thicker is needed - it's not a roll-bar). bend it, drill some holes:



file holes for carriage bolts:







scribe said carriage bolt so i could grind flush:


mount for welding:



weld and grind welds smooth:




grind smooth:



bend (and i decided to re-weld the back for strength)



test fit (yes, i plan on drilling for another mounting bolt. there is torque on this setup):



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next is the main linkage arm for the hoops (cut, scribed and ground):


both:


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then my garage timer went off and i was back on baby-duty :)


oh - and i have already bent the two main hoops. i'll snap some pictures of them. i used the same 1/2" conduit as the luggage rack i built: https://www.speedsterowners.com/forum/readmsg.asp?t=22805

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to date:
1) hardware = $12
2) steel stock = $8
3) conduit = $20

You hve MAD fabrication skills, not to mention abilities..... Its going to look great.

I'm impressed! Appreciate the tech info with pictures. We need to bring you to Carlisle and have you conduct a tech session! I'll buy you first egg samich!

Go ManGo!! I have been looking forward to your frame build. When finished, would you be so kind to furnish the critical dimensions and metal sizes to us lesser mortals? I want to build one of these also, but since you are blazing a path, please lead the rest of us to a better top.

About a year ago I scored an original two-bow top from a '51 TD, the idea being to adapt it to carry Bridget's existing top. I could tell just by unhooping it on the garage floor that it wasn't going to fit, so it's been sitting, folded up on a bench ever since, waiting for the right combo of bravery/foolhardiness and inspiration.

So thanks for that.

thanks guys and ed - i'm just doin' my part

i like updating this thread as it keeps me thinking about how to solve the design and pressure on to finish it.

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i picked up some nylon washers today and some more metal just in case i'm in the middle of fabrication and need something/ (add another $20 to the running total)

i think i was nearly asleep last night when a solution came to me that would allow me to mount the bows without welding (so i can take them on and off 50 times to make sure the fit is perfect)

kinda hard to describe, so i will just show you.

that is the piece that had me confused with the original design - how on earth you were supposed to put the top on the frame. my top has fabric loops that the metal bows slide through. unless you have access to the ends of the bows - i couldnt see how you'd mount the top on the frame. anyway - a moot point now that i've solved how i am going to do it.

stay tuned.

i want to get the hinge fully sorted to i roughed up the design:


with nylon washers:


back:


Video

"I think i was nearly asleep last night when a solution came to me that would allow me to mount the bows without welding ... ."

Great job (as always), Mango! That's the quote of the year right there. Raise your hand if that same thing has happened to any of you other SOC do-it-yerselfers?

My moments of great epiphany arrive when I am mountain biking.

On several occasions I've literally turned back on the trail and headed back home because the idea was so cool that I couldn't wait to get started on it!

Well...actually I mean get STEVE starte on it - LOL!

Mango - really diggin' this project. I also openly despise the top frame work that came with our kits. They look like an elephant shit out an umbrella.

angela

this is actually trickier than i thought it would be...

finished off the main mounts / pivots and drilled holes for the additional mounting hole.

i took all the hardware back because it had weird little symbols on the carraige bolt heads and i found some that are stainless that are smooth.

small details - i know, but... why not eh? $12 credit - $21 in new hardware. (oh - i bought new nylon washers too. nice and snug and a bit wider

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anyway - i decided to start with the back bow. start by getting the back as tight as possible. reason i started by saying it was tricky is i am working with an existing top, with existing tennax fasteners, and an existing header bow with triple latch mounts. the only area for 'tightness' adjustment is the shape and 'size' of the bow.

i was able to get a wickedly low/flush fold down - which i was also going for. i want to run a toneau without much of a budge of a frame. we'll see about that. i may be wishfully dreaming.

enough words - here are some pics.

please dont think that mount will be the finished product. i'll make it waaay nicer once i get the geometry right.

i'm a little concerned about headroom, so i may need to modify my first design:


second main mount bolt added:



disregard the front bow - it's not doing anything but getting in my way:


flush fold down:


front bow loose in this picture:


rear bow attached. i may fiddle with the shape of the bow (which BTW is the same shape as the front). i'm going to sleep on this for a few nights and see what i come up with:


that's all for tonight.

WOW! Mad skilz for sure!

Mango..does your top bow operating operating system employ and over-center lever where the two top bows meet on either side of the body?

sorry david - i gots no idea what choo talkin' about.

i think this may help articulate how the main bow pivots will work:
https://picasaweb.google.com/lh/photo/jepp35ln_11gCIz1g4nidTOVylwXSHkAKllvjOrJ9Eo?feat=directlink

From the video I see a flat horizontal bar and two vertical tubes, left and center and some lever on the right. What does the lever do when all is mounted on the car ?

it does three things:

1) folds it down further
2) locks it in place (once the rest is done this will make more sense)
3) provides additional 'tightness' when locked up. it pushes both bows up just a little bit.

oh ya - i should mention how i flatten the ends. i literally put them on the garage floor and bang with a rubber mallet to get a gradual transition from round the flat. then i finish it off in a vice (with soft-jaws so it doesn't make the crap out of it when i squeeze it)

ok - i managed to get another 2 hrs of garage time tonight.

re-bent the rear bow to make it fit tighter

then went to work on the front bow. i tried 2 different shapes. the rounder one was MUCH better, but i need to take some of the top roundness out (flatten the top so it doesn't pull the vinyl)



once i got hte shape i wanted - i measured and measured and measured - then cut



pretty much final front bow (i'm gunna flatten the top ~1/4" still):


tightened all the stuff up and clamped the front bow (remember - this will eventually be pretty. i'm going to paint it all ivory - keep all the hardware stainless and separate with vinyl washers):



then - to add the final tightness whatchamadinger is my oh so elegant pipe insulator. LOL


it's not installed in this pic (and you can see why i need to flatten the front bow a shade):



Now that the hard stuff is nearly out of the way - i can't wait to get to the folding mechanism. it sounds tricky, but once the bows are nailed - the rest is (should be) pretty straight forward.


That's it for tonight.

Mango make me one of these. How much are you selling them for?

Mango, that's fantastic, as usual. If I might offer a suggestion, though, it would be to not go with ivory. Maybe a gunmetal or a light carmel brown (like you used to bind your carpet), so as not to be a focal point in the car.

When the top's down, those ivory top hoops will really draw the eye to themselves, and I'm guessing that's not what you'd want.

hmm, good idea Cory - i hadn't considered that.

Matt - sorry my friend - i'm not at a place in my life (ie: no time as it is) to mass produce these.

i've made progress on the frame, but doing it in 1/2 - 3/4 hr chunks is kinda hard. the front bow is ready for welding. i've put in a round turnbuckle (like i did on the other frame) - but the same size as the tube.

closer - but very sllloooowwwwllllyyyy

work is nuts for me right now and yard work is piling up and it's getting sunny - so i want to insure the beast - but need a top.

oh - i changed the hardware again. :) machined some aluminum spacers as well since i didnt factor in how much the pivot needed to pivot down. all and all, minor stuff, but takes time.

Mango, when you're done with all that work -- the car stuff, I mean -- snap a photo from your favorite angle and send it to me. I'll whip a drawing up in pen and ink for you.

I really like what you're doing there, not just the time you take to post the photos and descriptions for the sake of demonstration, but also because I believe what you're doing is good for the hobby as a whole. You're showing the rest of us what really CAN be done at home, in the garage, by somebody who's willing to take the trial-and-error approach.

Thanks for taking the time.

it's truely fun and i enjoy the working with my hands aspect. i do brain work all week (and sometimes weekends - boooo), so problem solving and fabricating something incredibly tangible is awesome. thanks for the kind words.

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now - on to progress.

i got me a solid hour and a half of garage time tonight. i welded up the front hoop adjuster and welded it to the main pivot.

then i latched the front header to the windshield and tenax'd the floppy top to the car (with the two bows folded down, installed)

i then crawled in the car and folded it up where the bows would fit into the top.

ahhhhhhh yaaaaaaaa.

apparently all the anal measuring i did paid off. tight as a drum. literally. i dragged my wife out to the garage and boomed (like playing drums) on the top all over it. i'm pleased.

even cooler was how it articulates. it folds down a LOT lower than i had hoped. this means with the top on / folded and all the rest of the frame fabricated, there is a very good chance that it will not be higher than the edge of the body. (ie: i can run a tonneau with no budge)

anyway - i have pics, but i'm on my laptop, so i'll post them when i can upload them.

by far the hardest part is not 100% over. :)

that's it for tonight.

so made some progress tonight.

kinda funny -

i put my little 2 year old daughter to bed and waited ~30 minutes and headed to the garage. i figured she was asleep.

cutting, banging, etc, i hear.. 'ddddaaaaaaaadddddyyyyyy'.

i go see what's up.

'what dat noise?'

'i'm making stuff in the garage'

'oh..... ok'.

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anyway - i started fabbing up the front folding pivots. i've kinda been procrastinating this cause i wasnt sure how/where to start. driving home from work today - i figured it out.

here are some pics:

main hoops tack welded. (never mind the old paint on the inside - i'm going to clean that off)


turn buckle installed / adjusted:


video of top folding down (just two hoops). look how deep it goes


then i measured the front folding frame tabs and used 1/4 painters tape to 'gut check' it:


tabs getting the proper shape marking:


tabs all measured and drilled:


oops - now they are drilled:


making the carriage bolt mount:


all 4 done:


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next is cutting - welding, but not tonight.

Looking good! I have a couple little ones so I know how hard it is to find the time for projects. Great work.

well, my 4 day weekend doing an insane amount of yardwork is pretty much over and this is all i have to show for it for fabrication:



seriously, these little buggers took a fair amount of time to make. they are the 4 pivots on the main hoop. i wanted to spend time and match the circumference on the stainless carriage bolts. then a quick zip with a sanding disc to make sure the metal is ready for welding (and looks cool).

I've always found that the details cause the most pain, too. Like when your fingers slip and you belt-sand the skin off a knuckle.

Nice work, squaring out the carriage-bolt seats like that.

made some really good progress tonight. i am feeling like I'm close to the home stretch in figuring this rubix cube out.

doesn't look like much, but this is the main folding mechanism that attaches to the front bow.

look how flat it folds (i made some tweaks to the design - hope it doesnt come back to bite me. :)

anyway - the welds are not that pretty, but i cranked up the welder to get uber penetration as i'm going to be doing metal art on these (smooth, rounded, etc)

oh ya - don't grab the metal you just finished welding - even with mechanix gloves on. 1 second... sh!t

anywho... pics cause we're guys:

measurements for the DIY-ers:


ground clean, clamped:


part 1 of 2 welded:


part 1 of 2 drilled to the same geometry:


part 2 of 2 welded:


trial fit. i am going to not do the front bow attachment until last:

oh - here's my improvement:



it should fold down nice and tight

Great-looking articulation points, Mango!

Been away for a few days but, MAN! I gotta tell ya.....Those turn-buckle thingies in the top bows are just, friggin, brilliant!

closer

a lot closer

being a sunny Sunday afternoon - i made LOTS of noise in my neighborhood with the grinder.

did some cutting and some bending (more like banging) on the front folding setup. a surprising amount of geometry in this. more than once i found myself literally scratching my head...

got all the geometry mocked up then ground the welds down and flap-disc'd the metal to make it look like one piece of art:

from this:


to this:


and to this - finished them off:


measurements for the DIY-ers (this literally would have saved me hours and hours if i had this before):


mocked up (note i left the bottom mount/bar end thingy unfinished as i'm going to tie in the rear bow folding setup. if you got any of that):


folded up nice and stoopid tight (you can see the unfinished end on the lower pivot bar - that is going to be extended):

a side view to show how these all line up:


video of the front folding mechanism

garage door is opened - neighborhood kids screaming - not coming from my house LOL)

problems tonight....

(insert pissed off icon here)

i didn't have the geometry right on two of the three pieces i prepped so nicely above. i had to weld up a hole and do some serious mockup with the top up/on.

pretty time consuming.

i didn't have the front hoop pivot points (fancy little tabs) in the right spot and i was scratching my head as to why it did fold like i was expecting with the top up (front hoop where it slids through the top)

pushed a little harder and pop - my little spot weld popped off (note to DIY - this is why you spot weld it together and fully weld when it's finished)

good news is that it became instantly apparent where my mistake was. physics has a way of doing that. :)

so, i unfortunately need to cut/grind/weld more. all of which are not hard and i enjoy doing, but my garage time is only when my little stinker is sleeping.

anyway - one step forward tonight and two steps back that had to happen.

no pics cause everything is a mess right now.

Paul-

as you may (or may not) be aware, what you are undertaking is freakishly hard. I've done a fair bit of fabrication on my car, but the stuff you do most of us would consider really, really difficult, and this thing is over the top (as it were).

It's the geometry that makes this magic-- the rest is just welding and grinding. You didn't get it right the first time, but I know you'll get it right in the end. That's why we like to watch you make stuff. The fact that you document it so thoroughly is a real asset to guys that want to come along behind you.

I loved your luggage rack thread. This one just blows me away. Keep it up, man,

Ditto!

x3

I am in awe of your fabrication skills. I guess I need to learn how to weld someday.

thanks. it's nice to see folks still watching this thread too.

i am itching to work on this.

since most of the time i'm working on this right before bed - i seem to dream about it. last night was no different and as a result, i know exactly what i need to do.

only thing i am nervous about is tack welding the frame to the bow. i've already mounted the bow plate, but the idea of welding over my interior is NOT appealing. I have to do it to get the geometry right. just a quick spot weld - with gas, so there will be little splatter. lots of wet blankets.

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Funny - now that i look at it - i see the top mount pulling the arm more than it needs to:



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oh, and Lane - welding is actually pretty easy once you know the basics and how to setup a welder. i learned 2.5 years ago with a 12 week (2 nights/week) college course. best $$ i've spent on myself in a long time.