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tazz9924
I finally got the fiberglass ive been waiting for since before the corona outbreak. I picked it up from greyhound today (side note: dont ever ship greyhound, you pick up your porsche parts from a gas station in the ghetto)
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This was the biggest box ive ever received, i WAS gonna pick it up with my kei car, Honda beat but i listened to reason and took a volvo.... wise choice.
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Everything is a bit rough.. especially the fenders but i can make it work. The front bumper is decent enough to make me happy, and i knew the side skirts were wrong buying this stuff but oh well. I think they’re sheridan skirts if anyone needs them let me know, they are in good condition. Add it to the fiberglass stockpile in my attic.
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tazz9924
I was delayed a few days because i was waiting for bolts but im back at least for a little. I measured and measured again until i got the subframe nice and square so i could make decent lines to cut into my chassis.
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Andyrew
Welds look nice!

BTDT on the greyhound in the ghetto... About the only way to ship BIG items though for normal people money..
tazz9924
QUOTE(Andyrew @ Apr 28 2020, 11:27 PM) *

Welds look nice!

BTDT on the greyhound in the ghetto... About the only way to ship BIG items though for normal people money..

oh i know, but it was a very funny experience but ill spring for freight next time. that way it wont take a month and a half and i can stay in the comfort of my own home
jd74914
QUOTE(tazz9924 @ Apr 28 2020, 10:21 PM) *

What's this holding? If it's seeing any real load and not heavily gusseted you're likely going to rip the tube in the HAZ outside of the weld. BTDT. Sometimes gussets don't even do too much.

The welds look nice! first.gif

I know you're going along a pretty good clip but below are some pro-tips*:
1) Get a second regulator and purge the ID of the tube frame when you full weld it. Quality will be much higher.
2) Clean the inside of the tubing with a pipe cleaner.
3) Drywall mesh does a really good job of cleaning mill scale off without loading up. A quick pass of the wire brush in one direction afterwards takes care of the rest.
4) For any coped tubes going into a tube without air connection (like your gussets), drill a small hole so 1) gases expanding inside don't cause your pool to blow out at you near closing the weld and 2) you can purge.
5) If you use 4130 or any other high carbon steel, be sure to normalize the weld HAZ to keep it from cracking under use. You can do this with a torch (instructions in Engineer to Win IIRC).

*Not a pro welder, but I've welded 5? (can't remember the full count now laugh.gif) full tube framed formula cars and a bunch of semi-tubed cars.
jd74914
QUOTE(URY914 @ Apr 9 2020, 06:56 PM) *

I have one word of advice: Triangulation.

What you did isn't really triangulation from an engineering sense. You made triangles, but they don't connect to the nodes so all you really did was put all of your tubes in bending vs. making the structure a two-force type truss member. That misses out on a lot of stiffness.

The spots you've done on the floor don't really matter, especially when you rivet on an actual floor because that shear plate will take care of any bending more efficiently than triangles. When you do to suspension bracing really try to make sure all of the nodes are braced directly with tubing running right in them. With properly triangulated nodes you don't need the coped tube gussets (you can put "tacos" if you want, but they really aren't necessary).

Rudy's build is a great example of good node structure with practical considerations for being a "914." His is a better inspiration than formula cars since it also incorporates the practicality of a car.

http://www.914world.com/bbs2/index.php?s=&...t&p=2361501

I'm not trying to be a dick, but rather provide constructive criticism from someone who has been there...please don't take above as me trashing your project, your work looks great! smile.gif
tazz9924
QUOTE(jd74914 @ Apr 29 2020, 07:48 AM) *

QUOTE(URY914 @ Apr 9 2020, 06:56 PM) *

I have one word of advice: Triangulation.

What you did isn't really triangulation from an engineering sense. You made triangles, but they don't connect to the nodes so all you really did was put all of your tubes in bending vs. making the structure a two-force type truss member. That misses out on a lot of stiffness.

The spots you've done on the floor don't really matter, especially when you rivet on an actual floor because that shear plate will take care of any bending more efficiently than triangles. When you do to suspension bracing really try to make sure all of the nodes are braced directly with tubing running right in them. With properly triangulated nodes you don't need the coped tube gussets (you can put "tacos" if you want, but they really aren't necessary).

Rudy's build is a great example of good node structure with practical considerations for being a "914." His is a better inspiration than formula cars since it also incorporates the practicality of a car.

http://www.914world.com/bbs2/index.php?s=&...t&p=2361501

I'm not trying to be a dick, but rather provide constructive criticism from someone who has been there...please don't take above as me trashing your project, your work looks great! smile.gif

Noted! i understand what your saying, in my design it is a major part. The floor design i took from a trusted source, and i misinterpreted what u meant. Love the detailed responses though!
tazz9924
I continued mounting the front subrame. Still sitting perfect. In the future once i get some more metal on this thing im going to reinforce the mounting points because as they stand, they are week. More to come!
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tygaboy
Holy Moley! That bad boy will be a roller soon! aktion035.gif
Come to my shop and help me build my tube chassis...
tazz9924
QUOTE(tygaboy @ May 6 2020, 02:02 PM) *

Holy Moley! That bad boy will be a roller soon! aktion035.gif
Come to my shop and help me build my tube chassis...

@tygaboy ill need a plane ticket and Perdiem chowtime.gif
tazz9924
Finally! im done welding up the front subframe in place... for now. It’ll get a little more reinforcement in the future but now i must cleanse myself of the hatred that was welding the front mounts up. Now on to mounting those front struts!
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tazz9924
Made my strut tops! Ill be honest i was very excited about making these because i knew they could look good.. and they do! I would’ve preferred to bend the steel instead of having weld joints but i was assured of its strength so ill take it.
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914forme
They will be plenty strong as the top plate is taking the majority of the force. The other forces will be applied at the attachment points, depending on your plans for attachment, you may need to add something down the sides to transfer the loads.

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Liking the progress, and the fact it is a down and dirty build.
tazz9924
major progress.
I cut the holes in the strut tops to allow for the strut to pass through.
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Next i welded in what ill call: The bar that links my struts together and is critical to my camber. I used quite a bit of scaffolding to make sure it was setup right. I used actual measurements from a boxster to space the struts correctly. One of the complaints of the boxster is you cant get enough camber from it stock. I added 1/4” of strut top negative camber. Its not much but i should be able to get a little more out of it if need be. The control arm angle was a point of contention for me. I couldnt find a boxsters control arm angle at full droop, so i... i eye balled it.. intelligently. i know it should be around 1 degree up at ride height, which from what ive read stock ride height is where the strength of this suspension lies. I settled on 20 degrees at full droop. I figure the car will settle an inch when it sets on the ground which will bring it somewhere close to where it should be. This car will have adjustable suspension so i can tune in the control arm angle as needed. It also sets the strut tops fairly low, which is a plus in my book.
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Once i finished the; The bar that links my struts together and is critical to my camber bar I then moved onto caster. I matched the caster i measured on a boxster and matched it with two temporary bars. now onto bigger and better things!
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tygaboy
Isn't it fun triple double checking all the measurements and questioning your assumptions over and over? Are you laying in bed each night rethinking how you're going to design and build that next section? blink.gif

You're making great progress! Can't wait to see more.
Andyrew
WOO solid progress!


You should throw your video's in this build thread when your done with them.
tazz9924
QUOTE(Andyrew @ May 16 2020, 06:13 AM) *

WOO solid progress!


You should throw your video's in this build thread when your done with them.

I totally spaced on that!
If you want to see my beautiful(?) face actually working on this, here’s the link to my video: https://m.youtube.com/watch?v=tO0ksx4SHTo
tazz9924
QUOTE(tygaboy @ May 16 2020, 05:29 AM) *

Isn't it fun triple double checking all the measurements and questioning your assumptions over and over? Are you laying in bed each night rethinking how you're going to design and build that next section? blink.gif

You're making great progress! Can't wait to see more.

Oh god its all i do!
JOEPROPER
Nice video.
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76-914
Probably the fastest build yet. beerchug.gif
sb914
I love the video!! Keep them coming.
tazz9924
More bars went in today, but not every day goes smooth even when you get in a groove. First i made the bars that go from the dash bar to the struts, easy enough. Some complex angles that aren’t immediately obvious but some flap dish work and its all good.
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Next came the bars the go from the main chassis rails to the: The tube critical for my camber and attatching both struts. These bars were a pain! First i tried to link it up with the bar that attatches the two chassis rails. No Beans. 4 try’s down the road i gave up on that pipe dream (get it) and moved them back two inches and bingo! i even got to reuse a mistake bar.
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I then attempted to notch up a triangulation bar for the front section but i messed up three times on the same bar. I learned from my mistakes but dang i really wanted to start finish welding mad.gif
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I did notice this thing looks like a teenager in that old school head gear, braces things. Do people still get those?
tazz9924
I can finally sleep tonight. I got that diagonal bar in with major troubles. Three attempts and a lot of hammer blows and its in.
tazz9924
I figured id give a little update. My last couple days have been anger inducing ive made little progress despite putting in a fair bit of time. Sometimes thats just the way it goes. I made a little subframe that’s mostly so i can align up the rear suspension. Im highly considering changing/redoing that again in the future, maybe tubular next time idk.
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It however will serve its purpose as tomorrow i embark on finally mounting that rear suspension and making my car whole!.... a little teaser:
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76-914
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Andyrew
Good work! Fast progress! Keep it moving while you have the energy!
911GT2
QUOTE(tazz9924 @ May 22 2020, 08:23 PM) *

I figured id give a little update. My last couple days have been anger inducing ive made little progress despite putting in a fair bit of time. Sometimes thats just the way it goes. I made a little subframe that’s mostly so i can align up the rear suspension. Im highly considering changing/redoing that again in the future, maybe tubular next time idk.

My advice to you, step away sometimes.
I know this from experience, from building my buggy that when it feels anger inducing or like you're making little progress to something else for a while.

Let your project sit for a couple of days and get back on it when you feel motivated again.

You can't do quality work when you're frustrated. And you end up doing it twice.

Ask me how I know. beerchug.gif
tazz9924
QUOTE(911GT2 @ May 24 2020, 12:46 AM) *

QUOTE(tazz9924 @ May 22 2020, 08:23 PM) *

I figured id give a little update. My last couple days have been anger inducing ive made little progress despite putting in a fair bit of time. Sometimes thats just the way it goes. I made a little subframe that’s mostly so i can align up the rear suspension. Im highly considering changing/redoing that again in the future, maybe tubular next time idk.

My advice to you, step away sometimes.
I know this from experience, from building my buggy that when it feels anger inducing or like you're making little progress to something else for a while.

Let your project sit for a couple of days and get back on it when you feel motivated again.

You can't do quality work when you're frustrated. And you end up doing it twice.

Ask me how I know. beerchug.gif

I know, i got a deadline because i have to move soon and id like it to roll asap. The little subframe was not of the utmost importance for the drivability of this car so i let myself do it frustrated. I cant wait to be done with this move and get a normal life back laugh.gif
tazz9924
Sunday was a big day. After spending most of the day outside in the garage i completed a lot of things i needed done. First i made some spacers and mounting plates for the rear subframe mount. Some plasma cutter and like an hour of grinding later and they came out great. (i forgot to take a picture) Next i made up a ( shaped bar to connect those plates together, made another one of those fancy camber bars that go between the struts. I lined it all up and tacked it together and presto! Our first picture.
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I decided that i needed to change the subframe i already built and didn’t like, so i did. I made it slightly thinner which helped it fit between the main hoop better and cut it to length which helps with the wheelbase issue.
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Now came the moment i had been waiting for; Time to put it all together and line it up. First i used a trusty ratchet strap to align the rear stuts to their proper angle. Simultaneously i had the subframe up on a jack with a piece of wood to balance it. I used my other jack, a new drill in a box, lots of scrap metal, and some card board to set the subframe height at the chassis. Its ghetto but it worked. I then got the correct rake of rear subframe.
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Next i setup a string alignment setup to make sure the subframe was center left to right. At some point i had to sit down and stare at it because this took like two hours to line up. But finally i got to tack everything in place and thats where we are now!
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tazz9924
Quick update: i picked up my doner car today! I put it in my nee trendy looking shop biggrin.gif Click to view attachment
And next to my daily driver
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tazz9924
A lot of progress! ill be brief because im tired but i basically reversed a week of work by cutting the back half apart allowing me to move houses. Next i set up my garage and car and got to work. I leveled the chassis and began work on the rear suspension in many many frustrating hours of work paid off by being able to sut back and look at what ive done.
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bkrantz
I get dizzy looking at the tubing angles in front of those "creative" wall designs. Are you sure things are straight?
Andyrew
Sweet! Love the progress!
Andyrew
Also that Beat is Sweet!!!
tazz9924
QUOTE(bkrantz @ Jun 21 2020, 07:37 PM) *

I get dizzy looking at the tubing angles in front of those "creative" wall designs. Are you sure things are straight?

Oh i know! i had to put up a shelf and i was totally convinced it wasn’t level, it drove me crazy
tazz9924
Its a roller kinda! I added a strut bar on the back and let the jack rip. Unfortunately i still need to “mount” the subframe. At the very least better, because as it rolls its held by hopes and dreams. But hey its celebration time cheer.gif
Two of the bars are temporary that are on the subframe btw.
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Carbon-14
Observations from afar,
looking forward to the 914 skins, suitably modified to be sleek, a stiff chassis to allow competitive performance.
Subaru power, should go, like.
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SolidWorks or a similar cad sw.
Basically, a GT40 replica's tube chassis, modelled in balsa, or Z88 fea, to plan the performance and weight.
https://www.google.com/search?q=tube+chassi...540&bih=746
https://fem-heroes.org/example-structural-e...-tubular-frame/
https://www.youtube.com/watch?time_continue...eature=emb_logo
https://www.ansys.com/about-ansys/advantage...ronger-race-car
Carbon-14
Those new fangled jackstands have me wishing they were wired shut, to insure they don't collapse, snafu.
Be safe.
tazz9924
QUOTE(Carbon-14 @ Jun 23 2020, 02:26 AM) *

Those new fangled jackstands have me wishing they were wired shut, to insure they don't collapse, snafu.
Be safe.

They arent the harbor freight ones, they are some amazon brand. So hopefully death isnt close?
tazz9924
QUOTE(Carbon-14 @ Jun 23 2020, 02:20 AM) *

Observations from afar,
looking forward to the 914 skins, suitably modified to be sleek, a stiff chassis to allow competitive performance.
Subaru power, should go, like.
Click to view attachment
SolidWorks or a similar cad sw.
Basically, a GT40 replica's tube chassis, modelled in balsa, or Z88 fea, to plan the performance and weight.
https://www.google.com/search?q=tube+chassi...540&bih=746
https://fem-heroes.org/example-structural-e...-tubular-frame/
https://www.youtube.com/watch?time_continue...eature=emb_logo
https://www.ansys.com/about-ansys/advantage...ronger-race-car

The rear section looks quite similar to what i have planed. I just have to change it a bit because i dont have any good mounting spots on the subframe to allow me to do that exactly.
Carbon-14

https://www.youtube.com/watch?v=ct7vmJkbt60


Information overloading, to determine the rigidity and weight of the chassis, from Maserati birdcage, to Porsche 918.
Lighter, stronger, stiffer, faster, quicker, all the factors of a homebuilt -14. Have mig, will travel.

https://www.caelinux.com/CMS3/
https://openscholarship.wustl.edu/cgi/viewc...context=mems411
http://www.vintageperformancemotorcars.com...ted%20frame.htm
https://www.code-aster.org/V2/spip.php?article912
https://www.finiteelementanalysis.com.au/fe...tin-motorsport/
.
tazz9924
Ill admit im a little stumped... Call it: i want to make the best decision but require the input of others to feel comfortable. So i need to mount the rear subframe but unlike most of the stages so far this to me seems less obvious. My big issue is how to best mount it when the mounting plate is 90 degrees to the direction my bars are coming at. Heres a picture of what im dealing with: (the red highlights are the subframes mounting spots)
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I also have a nifty drawing showing where the trans will sorta sit when its on:
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My initial reaction is to add a bent tube meeting up with the bottom of the main hoop and some tubes linking the bar above it with the bent tube shown:
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Alternatively i could add a tube with just a 90 bend in it meeting up maybe 6 inches lower than the parallel bar above it kinda like this with some more reinforcement tubes:
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This is my dilema, any input is appreciated. Even just linking someone engineeringly minded would help my cause!
@Carbon-14 ?
76-914
QUOTE(tazz9924 @ Jun 26 2020, 07:39 PM) *

Ill admit im a little stumped... Call it: i want to make the best decision but require the input of others to feel comfortable. So i need to mount the rear subframe but unlike most of the stages so far this to me seems less obvious. My big issue is how to best mount it when the mounting plate is 90 degrees to the direction my bars are coming at. Heres a picture of what im dealing with: (the red highlights are the subframes mounting spots)
Click to view attachment
I also have a nifty drawing showing where the trans will sorta sit when its on:
Click to view attachment
My initial reaction is to add a bent tube meeting up with the bottom of the main hoop and some tubes linking the bar above it with the bent tube shown:
Click to view attachment
Alternatively i could add a tube with just a 90 bend in it meeting up maybe 6 inches lower than the parallel bar above it kinda like this with some more reinforcement tubes:
Click to view attachment
This is my dilema, any input is appreciated. Even just linking someone engineeringly minded would help my cause!
@Carbon-14 ?

Pm curbandgutter. I was just talking to him about your car. He is finished with his tube frame build. Well that portion any way. His is stretched and widened. Rudy is his name @Curbandgutter
Carbon-14

https://www.youtube.com/watch?v=MjkLr9CWlHk


https://robotics.ee.uwa.edu.au/theses/2011-...me-Waterman.pdf
The references noted are good reads to get a handle on building a stiff chassis, like the racers of the past seventy years. Compromises and assumed risk are some of the factors in welding up the frame, testing it's strength and performance on the skid pad. There is an incredible wealth of information and examples and now, available software to simulate and stress test the cages, chassis, and suspensions.
The answers to all the questions are there, and for sure it's all been tried before.
For casual street use, a less substantial box would be enough, a racing cage would of course be much more robust, heavier and neccessarily torsionally stiffer, some survivability built in. Twelve hundred horsepower turbo engine in an 1800 lb racecar would be very quick, if kept under control, while racing.
Looking forward to the solutions and installations of the drivetrain and suspension.

https://www.youtube.com/watch?v=iIKHocge9Sc

tazz9924
I have an easily digestible build up date in the form of a youtube video!

https://www.youtube.com/watch?v=5jXG65IEicw

I also have a good regular update coming up!
EdwardBlume
Damn this thread is sexy! beer3.gif
andrewb
I always love the famous 'can do' attitude of you Americans. No surprise that there have been so many amazing achievements that depended on guts and determination.

I was already gobsmacked (that's a good old English word) when this thread started that someone could just kick off with a bare garage floor and build a tubeframe chassis from nothing. Just for kicks he then moves to a psychedelic chamber - to make it even harder ??

And then the welding mask comes off .................and he's young enough to be ....I dunno, I give up. Utmost respect to you Elliott - how you've achieved those skills and depths of understanding in such a short time I'll never know. I wonder what you'll be achieving in 10 more years. Keep it up.

Regards

Andrew
tazz9924
QUOTE(andrewb @ Jun 29 2020, 05:37 AM) *

I always love the famous 'can do' attitude of you Americans. No surprise that there have been so many amazing achievements that depended on guts and determination.

I was already gobsmacked (that's a good old English word) when this thread started that someone could just kick off with a bare garage floor and build a tubeframe chassis from nothing. Just for kicks he then moves to a psychedelic chamber - to make it even harder ??

And then the welding mask comes off .................and he's young enough to be ....I dunno, I give up. Utmost respect to you Elliott - how you've achieved those skills and depths of understanding in such a short time I'll never know. I wonder what you'll be achieving in 10 more years. Keep it up.

Regards

Andrew

I appreciate the kind words, you have a good one!
tazz9924
Ok this is the last update for probably a couple weeks because i have to go racing in wyoming, but, i settled on a design to tie in the rear subframe. This involved one tube bend and then notched in three places. I didn’t know if id like it going in, but it came out killer. Thanks to my chassis builder friend who suggested the idea, then helped me build it!
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rhodyguy
Are you back in Tacoma?
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