Tag Archives: CAD programs

Still working on the design

I can’t leave the house with the rain and thunderstorms and the flood watches, so I have been reading superhero books on my Kindle app and moving boxes representing assemblies around in my CAD program.

OK my current design method is to assign things a box that describes the space they occupy, rather than the actual object itself, and then move the boxes around until there’s no overlap. Some boxes are fixed, like the engine/transmission box and the body box, while some are not even fixed in size, like the radiator box that changes width depending on the radiator I’m trying to fit. I think there is a possibility the smallest radiator in the catalog will be enough to cool the Pentastar after seeing the stock radiator for one of the vehicles it is installed in by FCA. That simplifies packaging considerably, because I can figuratively put that radiator beside the steering box and have room left over for a bowling alley. The joker in the deck is the OEM radiator is double-row but the catalog radiator is double-double-row with  1/3  less frontal area but a 2.25X thicker core with more fins, and I lack the data to make a direct comparison. The “double-double” refers to the tubes in the core of the catalog radiator having more than twice the heat rejecting capacity of a round tube, making the double row core the equivalent of a 4-row. There is a simple formula for comparing radiators of different designs, but catalog descriptions rarely have enough information to allow its use. And that goes double in this case, with different chunks of the equation missing from the 2 catalog descriptions. But it is my SWAG that the 22″ catalog radiator will be roughly equal to the OEM radiator, especially after I learned the replacement OEM radiator was also used for much larger engines and is just sold as a replacement for the Pentastar because it fits the hole. Ima just hafta put a huge electric fan on the catalog radiator to make sure there’s enough airflow to remove the heat, which is what I would have had to do anyway, just maybe not as huge as I’m thinking about using now.

The radiator box combined with the steering box are the same width as the engine box, which is the same width as the firewall but extends a touch to the right because of offset to balance out my “big bones” sitting behind the steering wheel on the left. Which is a very roundabout way to say the radiator and steering box are together the same width as the firewall. And that I could install a wider radiator without increasing the frontal area of the car. This also means that there will be a large hole to the left of the engine that could be use as an escape path for cooling air, or a place to install an oil cooler facing sideways. Looking at the picture right now there are several places to install a small oil cooler, above the steering box there is a 5″ wide by 18″ tall space, there’s a 7″ tall space under the radiator that could run the width of the front end if the hoses would fit under the steering box. But as I don’t see any oil coolers near those sizes in the catalog…the question is moot.

And I just found a picture online of the engine in side view, with a tape measure in clear view to use to scale from and all the driven bits hanging off the front with the belt and pulleys exposed to measure. Something to make the engine box more accurate in the for and aft dimension, might mean a bigger box, might mean a smaller box, but either way it’s a more accurate box.

And writing note, when I get on a roll writing it’s pretty much stream of consciousness, but I still “feel” the punctuation and capitalization. What I don’t have a feel for is when I need a paragraph break. And my proofreader program knows fvck-all about paragraph breaks so I don’t get a blurb about needing a paragraph like I do about passive voice or homonyms. What I’m trying to say is I know I need more paragraph breaks in my writing, I just don’t always know where to put them.

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Still thinking about the rear suspension on the Mid-Bucket

Yes I was being dangerous again, thinking and all. Basically I’m thinking about details now, how to arrange the heim joints on the plate so they don’t interfere with other bits and are still adjustable for what needs to be adjusted.

My first thoughts were they needed to be set up in an equilateral triangle with one located center bottom. Then I ran some adjustments in my mental model in that configuration and there too many interactions in that configuration. What it came down to was every adjustment would change another parameter that did not need changing (or maybe it did but not at the same time and maybe not in that direction). So, change to a right triangle with the sides adjacent to the right angle located vertical and horizontal. Changing the camber will change the toe slightly but changing the toe doesn’t affect the camber. The longer the distance between the vertical pair of heims and the toe heim the less a camber change would change the toe. Thinking about it more putting the toe heim on the horizontal centerline of the rear axle with the camber heims equally spaced in relation to that line would give the least toe change with camber adjustments, especially if the camber heims were adjusted in equal and opposite directions. So, maybe not equilateral, but isosceles with the point on the horizontal center of the axle and the short side vertical.

Now that that part is decided how to connect it to the de Dion truss? The reason the equilateral triangle first suggested itself was using the horizontal part of the truss to support two of the joints and a side support off the vertical for the third. And as I think about it I can get zero interaction with the right triangle by leaving one joint fixed, and adjusting the other two for toe or camber, depending on which axis they are on. Which tells me that the horizontal pair mount to the horizontal truss, and the vertical pair the vertical, and the heim that is on both axis is the fixed one.

See how problems can be solved if you just put them in words while thinking in 3 dimensions? I know, not everyone can do that, I have what amounts to a 3D CAD program in my head. What frustrates me is I can’t just copy and paste from my head to my computer like I do when I write stuff on my phone. I mean I can see it perfectly, but I can’t reach in and pull what I see in my head out where everyone else can see it, and I lack the skills to enter what I see into a real CAD program, and the patience to learn how. I know, that last one is on me, my problem. But I can even see how the flanges for the various heims interact to add support to the mount for the hub bearing with minimal added weight. Just connect them around the bolt pattern for the hub bearing and they have enough vertical depth to keep the mount from flexing. I just need to leave enough room for the bolt heads and a socket to drive them into the holes on the flange on the hub bearing. All the major forces go directly into that hub mount, bypassing the de Dion truss which has been reduced to keeping the wheels pointed in the right directions on two axis and the same distance apart all the time.

Speaking of the same distance apart, it looks like this is gonna be a very wide bucket, about 6′ 3″. The front axle is going to be 56.5″ wide compared to the usual 48″. That’s because the hub-to-hub width on the donor vehicle is right at 65″± compared to 56″± for the usual hot rod axles. This solves a lot of problems with the suspension, while introducing others. But mostly it solves problems or makes them tiny. And tiny problems are either easily solved or ignored.

And on that note it’s time to say buh-bye until next time. Opus the Unkillable

“Enjoying” the company of my in-laws on a Wreck-Free Sunday

I’m typing this as I watch the rain delay at the postponed Firecracker 400 (I refuse to refer to races by sponsor names, for the most part the races existed long before the sponsor even thought about “sports marketing”). So, watching nothing going on and listening to screaming children running around.

Going back to the race, the expected wrecks have led to unexpected drivers being in contention for the win today. The current leader during the rain delay is Aric Almirola in the Richard Petty Motorsports 43, the King’s number. And NASCAR just declared the race official making the 43 the winner. Yay King!

So I switched to the IndyCar race where they are dicing back and forth around the Tricky Triangle at Pocono. While there is dicing going on up front there is strategy taking place at the back with drivers running the full lean fuel map with as little throttle opening as possible to maintain position on the lead lap so that they will be in front when the leaders have to stop for more E-85. And it didn’t work, as the fuel warning light came on with 4 laps to go, putting Juan Pablo Montoya in the lead and winning the race in his first season back in IndyCar. The race was done way early because they only had a single caution period for what appears to be an engine failure for Graham Rahal. He was moving right along and then all of a sudden there was no engine noise and the car was going backwards with the back tires not turning. So with only the one caution they ran a record speed for a 500 mile IndyCar series race of just over 202 MPH. They have an extra hour of TV time to kill before the next show, so I get to see the Indy Lights race from Pocono several hours early. After this the rebroadcast of the British Grand Prix will be shown.

And I read in the paper that Mark Cavendish was involved in the pack wreck on the first stage of the Tour de France, separating his shoulder and probably ending his Tour. I haven’t seen any news from this morning’s stage yet because honestly, I’m just not interested enough in the Tour this year to turn the TV on that early. I probably won’t turn it on this evening either.

I have a new CAD program for this laptop that I’m trying to figure out so that I can make a drawing of the 20/20 crank forward bike with full suspension that will upload to the media center for this blog. I really want you guys to be able to see what I see in my mind’s eye when I write about things I want to build. To that I managed to grab a working USB 3 button mouse from a yard sale “take this free” box, which will prevent the spurious clicks I get with the touch pad on my laptop from causing false data points in the drawings. The touch pad is not that big of a problem when web browsing and blogging, or using the dice app playing RPG sessions, but it was a major pain in the butt trying to draw using the CAD app. The CAD app is based on AutoCAD, so after I learn the commands and shortcuts for the app I’ll have a leg up on installing the Linux version on my desktop computer. Now to show what the Sprint-T looks like in my mind’s eye I will need to figure out how to transfer the pictures I have of the Speedway T Bucket body to the program.

Most of my immediate family came up to celebrate my mother-in-law’s 80th natal anniversary, including the elder daughter all the way over from Scotland. We last saw her back when my Dad died back in 2012 when she came to share Thanksgiving and ended up going to a funeral. I’m very glad to have her with us.

And the hardest thing we have had to do this weekend is find vegan dishes that Elder Daughter can eat. This part of NY is not rife with vegan options, there are some sure, but not a lot. She’s rather militant about her diet, for good reasons. Her diet is about the only way she can fight global climate change and factory farming, so breaking it has political overtones that are not good in her eyes.

And I think it’s time to put this post to bed and get on with my vacation (and life). Y’all have fun tonight.

PSA, Opus