Tag Archives: Mini Sprint-T

Sleep cycle is borked

And if you think daytime TV is bad try finding something good at 0200. I tried looking for stuff for the Mini Sprint-T as currently planned but the only Subie engines I found were in $25-$200 kits so I have a request going in the Facebook Scale Model Club for someone with a built WRX or similar turbo Subie they don’t want anymore, that I can rob the engine from. I just did that right before I started doing this post, so not enough time for a response yet.

One thing I did find that is still entertaining at 0200 or later is YouTube. I went back and caught some episodes I missed from my subscribed channels before they got big, surfed some recommended videos, and generally just wasted time between sleeps when I wasn’t trying to come up with a blog post or clear out my emails. Twitter was the usual sewer, for the most part. If it wasn’t for the fact I find stuff out on Twitter several hours before the news comes on I would just delete it from my phone.

So, anyways, I found out that one of the people in my RPG group has a new job doing something he actually spent tine getting a degree to do, which is going to make it pretty much impossible for him to do any game sessions during the week, which means because I’m going to be glued to the tube (actually the flat screen) all this weekend watching the three NASCAR touring series race their final races of the season and determine their champions we are not getting to play this week again after so many weeks of other people having scheduling issues. My fault this time.

And I really don’t have anything to say today except, Next Time!

Advertisements

I think world peace is only marginally more difficult than scheduling an RPG

Well, I was supposed to be playing Shadowrun about now, but another player got called in on her day off, so I’m pecking at the keyboard and trying to maintain low enough levels of blood in my caffeinestream (yes I have caffeine with blood in it instead of the other way around) instead of slashing my way through monsters and solving puzzles.
But we have rescheduled for Friday it looks like right now, with Thursday as the alternate if we can’t get Friday to work.

I’m really looking forward to finishing this dungeon crawl so we can get back to DFW and solve some things we left undone, and I can spend some karma points on kicking my skills up and maybe getting more contacts. Right now my skills are what would be max for character creation, but I have enough accumulated karma points to raise one or two another point and get some points in skills like Observe, and probably Negotiate. I have already maxed out my levels in Badass, which does help in negotiation rolls, but actually having that as a skill would be an asset as well. Right now my character uses his money and willingness to spend it on making people’s lives better as his primary negotiating tool.

And speaking of spending money helping people I really need to finish setting up the Solstice Barbecue and Pig Roast or I’m going to have about a hundred angry trolls and about the same number of orcs standing around the house expecting to be fed and no meat cooked for them. And I have to finish this Run and get back to DFW from Egypt if I want to do that. In game this is an annual event that I have been doing for decades now, and a big part of why the gang wars in Garland don’t get fought in my neighborhood. We have a DMZ of sorts for several blocks around the house, and there is a Pax Opus on people going in and out to use the food pantry, or the homeless shelter in the basement. That’s what most of my running fees go to, and a good chunk of my TI retirement in-game. In-game I’m almost-rich from all the times I got killed but didn’t stay dead and sued the person who killed me, and got a fvckton of money from TI for keeping them from getting taken over by a much larger corp, which I wasn’t supposed to survive but guess who can’t stay dead in-game? 👿

On the Mini Sprint-T I’m going with the SBC and the 700R4 transmission because that is the most complete engine and transmission combination I have and also the most likely to be installed as a crate combination should I get the money. Also, I don’t have a 1/25 scale Subaru to stuff in there. The Subie is actually cheaper and the same power as the SBC not to mention hundreds of pounds lighter, but Not Generally Available outside a kit, so no Subaru engine. 😛

The bandaids are off

Well the full extent of the damages are now visible as I am between bandages. I think the thumb will be OK going without another bandage, but the index finger needs antibiotic and another bandage. The index finger got really close to losing the chunk off the tip, but I think it will heal without the big ugly scar.

The index finger in all its gory glory.
Very close to losing the tip of my finger.

The thumb injury can barely be seen a day later, but it bled like I severed a major artery when I did it.
'Tis but a scratch.

Construction on the Sprint-T will have to wait until the index finger heals over so I don’t get bad stuff into my bloodstream through the break in the skin, but I have been thinking about order of construction for the frame.

First thing I need to make are the roll hoops because they dictate where everything else in the frame has to go. And I have been thinking about how to make two perfect hoops. The raw stock is a thermoplastic, meaning it can be formed easily when warmed to something under its melting point but above room temperature, a candle or similar is a good heat source for bending styrene plastic. I just need to use a round thing to bend around that has the same radius as the anvil of the tube bender, in scale, and a flat surface to make the second bend against to get all three legs in the same plane, easy-peasy. So, put the anvil of the mini bender on a board or something and put marks on the board for a 90° bend and where to put the leg of the first bend to get the distance between legs on the hoop the right distance apart. Put the top of the hoop on the mark for the beginning of the 90° bend with the leg from the first bend on the mark for how far apart the legs should be and make the second bend and cut the legs to length after bending.

The next thing would be to cut two pieces of raw stock to a scale 52″ for the main rails between the hoops, so the bracing inside the hoops will just clear the body when everything is together. And since this build is going to be fitted with a bellypan, the bellypan would be a useful place to use as a jig for getting all the bits and pieces for that level of the frame together. So cutting the bellypan to size, gluing the lower frame rails to it and the roll hoops to both seems to be the next logical order of operations. After that the crossmembers that run between the legs of the roll hoops seems to be next. Measuring the height of the top of the bellhousing for the horizontal brace across the front hoop and cutting stock the same width as the crossmembers would be the next step as would placing that member at the right height. Doing the same thing for the harness bar on the rear hoop would be next.

At some point I would need to bend the top rails for the frame and put them in, this would probably be a good time. Also for the diagonal from the top of the rear hoop to the bottom of the front hoop. The other diagonal is going to be more tricky because of the pickup point for the front of the swingarm coming from the rear axle. I need to see where the front of the swingarm is in relation to the diagonal to see if I have to make a jungle gym just for getting that point solidly located in space, or if I can just kink the diagonal a bit to catch it, then run another diagonal from the pickup point to the bottom of the front hoop to triangulate it and to the top of the rear hoop to preserve the triangulation of the front to rear diagonal.

And I have no idea where the top mount for the front coilover needs to be to clear the front tire at full lock and full bump, like when I hit a curb on a tight corner with the inside front tire. That would be an ungood thing to happen in a run, but to have the tire hit the frame would make bad plusungood, if not doubleplusungood. And yes, that was Orwellian New Speak used to describe an engineering scenario. I respect the classics. I mention this because I lack the tools to determine on my computer where the diagonal from the bottom of the front hoop has to be to clear the tire at full bump and full lock, without making the bracket on the axle any higher than it has to be for the coilover to clear the steering. Sure working from the side view I could just make the diagonal just tangent to the tire at full bump and call it “good enough”, but that would make the axle just a tiny bit heavier than it has to be, which is all unsprung weight. And my views on unsprung weight are only slightly less negative than my views on drunk drivers.

I can calculate the tangent based on diameter at the tangent point at full lock where the inner edge of the tire crosses the plane of the diagonal between the bottom corner of the front hoop and the top of the coilover, without needing to use 3D modeling but there are still width effects I need to account for and dynamic effects like axle flex and frame flex. Now frame flex is going to be measured in hundredths of an inch on the full-scale car, but I can’t get an accurate estimate of the load to determine axle flex beyond the load needed to get the spring compressed to full travel. At that load the axle flex is going to be in the same range as the frame flex, 0.01″ or less but the shock load against the bump stop could get another 0.02″ on top of that and times the moment arm that could get the tire as much as 0.08″ higher and closer to the diagonal, which would mean moving the top mount of the coilover even higher to clear the tire at full bump and full lock. Or I could just make the diagonal clear the straight ahead tangent at full bump and let the difference in height at full lock provide the dynamic clearance.

And if a picture is worth a thousand words I just posted more than 3000 words counting the pictures.

It’s fun (not fun) typing today

The RPG group had lunch before game today and I helped with preparations by slicing vegetables with a mandolin. I also sliced my finger, thumb, and a fingernail, removing chunks from each one. And seasoning the veggies with a little blood. Just a note, there is not enough salt in blood to season veggies. And also the bandaid on the fingertip makes it really difficult to type because it catches multiple keys in one keypress and I might have to go back and delete one, two, or sometimes three wrong letters to fix a word. Yep, I can hit 4 keys at once with this bandaid trying to hold my finger together. I’m really hoping we got the sliced bit back in the right place, because I know if I did the scar will be small and almost unnoticeable, and heal quickly, or a huge purple-red dot on the end of my finger if I didn’t get it in the right place. The last time I sliced the end off a finger it got lost in the pepperoni and it took about 8 years to grow back to the point that it didn’t constantly remind me that I cut off the end of my finger in a meat slicer, and about 25 years later you have to know where to look to find it. And someone got a surprise in their pizza.

And I’m back to the place I was a few years ago on the Sprint-T, needing a front engine RWD vehicle as a donor vehicle for the drivetrain. Or spending a ton on a crate engine and transmission. And I really don’t want to drop money I don’t have to on crate parts. Seriously the purchased parts will not work for anything other than a front-engine RWD car without lots of ballast (added weight). And without doing serious damage to the polar moment to the point that it might as well be front-engine. Seriously, the only way to save the TGS2 would be to stick the front axle assembly into a corner or closet and just pretend very hard it never existed, while I build a featherweight front suspension to keep the sprung/unsprung ratio close to something sane.

Also since I can’t make any progress on either full-scale car, I’m returning to the Mini Sprint-T. After getting almost all the parts needed to start the build, I got the idea that building the TGS2 was possible, and I stopped working on the Mini version. I think that was a mistake now, but back then it looked like the right thing to do to stop making a model and focus on the full-scale car. At least now I can take pictures instead of writing thousand-word descriptions of what I’m trying to do.

And last thing before I run this through the proofreader, Mrs. the Poet came in complaining about walking like a penguin and asking if there was a song about it and telling me I should use my music app to find out. Well, it turns out that there are not one, not two, but at least three different songs with the title “Walk Like a Penguin”, one kids song that I won’t inflict upon you, a remake of the Bangles song “Walk Like an Egyptian”, and a rap techno song that I likewise will not inflict on you.

And I got up after 3 hours of sleep to go play Shadowrun, so I’m starting to fade out here.

I did something nice for Mrs. the Poet

Yesterday I went out and got allergy and cough medicine for Mrs. the Poet. I also bought other things for her that she put on the list, but were really for me because after I got back she refused to take them and said they were for me. If I had known I would have gotten a different flavor of beef jerky. They had teriaki at the same price, but I thought Mrs. the Poet would like original flavor better.

This is going to be a busy week for leaving the house. I’m getting a lottery ticket later today, and Thursday we are finally going to get our taxes done, then do our anniversary night out, because Mrs. the Poet thinks she will be able to taste her mushroom swiss burger. Since Red Robin is one of the few places I can spend the pay I have been accumulating for about 18 months and it’s a sit-down type burger place we agreed this was the place to have our dinner. I have something I need to do Wednesday that eludes me at the moment but hopefully I’ll remember what it was before Thursday gets here.

I have been looking up tubing benders to find out what radius I can expect the 1.5″ tubing in the Sprint-T frame member bends, so I can get accurate scale bends for the Mini Sprint-T frame. I also discovered how to make a manual mandrel tube bender for cheap-ish. Not actually cheap, but cheap compared to a powered mandrel tubing bender you buy. Turns out the really pricey parts are the bending dies and mandrel, because you have to get or make a separate mandrel for every different wall thickness tubing you want to bend in every diameter you want. As an example I would need 1.5″ bending dies and follow rollers, then different mandrels for the 0.120″ and 0.060″ wall tubes to make sure I had wrinkle-free bends that would not be stress risers in the frame or roll cage. And for the Mini Sprint-T it turns out I would need a bending post 0.36″ in diameter to replicate the bend I would be getting in full scale.

Also I have been looking up costs of buying a Pentastar crate engine, without much luck. I still want to use that engine because the dressed engine and matching automatic transmission combined are within 5 pounds (±) of the weight of a dressed SBC without a transmission. Also the block rear face to front pulley measurement is under 20″ meaning I would have lots of room for the steering linkage on the front axle compared to the baseline SBC 27.88″. Also the torque is 241 lb-ft or higher from just off idle to redline with a peak of 268 at 4800 (or 269 at 4175 if I find an engine out of a Dodge 1500 pickup truck), meaning I could basically lock it in gear once I got it rolling on course in an autocross and just drive it like a big go-kart, gas, brakes, and steer. But given the 8 ratios in the slushbox, I probably would indulge a slap or two on the paddle shifters.

And now I really need to go rub Mrs. the Poet’s back and sides because her allergies have had her hacking for several days and her intercostals are exhausted from the coughing.

Weather still rotten, cats still crazy

And we are still p’. I may spend spent some more money gift card balance at Lowe’s buying cutting tools to make a Mini Sprint-T.

Mrs. the Poet went to the evil place (Wal-Mart) to spend her gift card to buy TP and tissue, and I used her bus pass to get to Lowe’s after she got back. I got a pack of single-edge razor blades and two packs of batteries, to power the digital calipers and the laser pointer cat toy. The trip up was by bus, but I just missed catching the bus as it came back around on the return loop, so instead of waiting the 0:45 for the bus to come back I decided to walk home. I managed to get back to the corner where the bus stops just before bus came by, meaning I managed to get the 1.67 miles faster than the bus managed to get around the whole loop and I didn’t even push hard to get there first. It felt good to get out and get a little exercise except for where I tore the middle toe up a few weeks ago pushing against the inside of the shoe, that still hasn’t healed up right. That was uncomfortable, but nothing I can’t deal with.

And as it turns out we don’t have cats, we have boring dogs in cat suits. Clyde ignored the laser pointer completely, I mean he saw it and reacted to it, but he didn’t react to it like a normal cat. No attack jumps or chasing the dot up the wall, just moving his head to track the red dot. Clint chased the dot for a little bit until he got bored and then ignored it after a few minutes. Then he sat down and just watched the red dot. And now he has just crossed his front paws and is ignoring the dot some more. Like I said, boring dog in a cat suit.

Another reason to wish I had a viable hot rod project

If I had a project like the Sprint-T sitting in my garage, instead of scattered around my office, I could distract myself from the idiots in power by puttering around on it instead of mentally screaming. At the very least I would be doing something useful to somebody.

Well I have been trying to get some work done on the Mini Sprint-T, as much as I can do given the condition of my cutting tools and measuring instruments. I really need to get new blades on my hobby knives and saws, and the battery in my calipers died making reading the distances more accurately than 1/16” a guessing contest. On a project where that scales as 1.5″ on the full scale prototype that degree of accuracy ain’t gonna cut it. But at least I can visualize where the bits will go on the real car. But yeah, 1/16” is the diameter of the frame tubes so I need to measure much more accurately than that. I mean .01″ is a scale 1/4” and you would notice in a heartbeat if the wheels were mounted that much off on the real car.

Tomorrow is the Daytona 500, aka “The Great American Race” aka “Opening Day”. Also my 40th wedding anniversary. But Mrs. the Poet has already said we aren’t celebrating tomorrow but rather on Monday, so I can watch the race and enjoy it without fear of reprimand especially since I’m buying dinner and paying for the bus passes to get there. I’m using the money from that one gig that pays in multi-store gift cards that work for the Red Robin in my neighborhood, and other places. This is also the same card I used to buy the lights for the kitchen, and the candy I gave her on Valentine’s Day. I can’t spend it everywhere, but I can get pretty good use out of it anyway.

Lots of road course racing this weekend

There are two road courses today on the tube and one yesterday. And there was an Indycar race from a short (by Indycar standards) oval. And for those wondering we are way north (about 250 miles) of the hurricane down on the coast so all we have gotten was a few showers and some slightly damp kitties. I’m worried about my Houston friends as H is getting drowned with feet (not inches) of rain. Last report they are expecting 5 feet of rain total. I have some friends living less than ¼ mile from the Brazos river which is way out of its banks last report. I’m especially worried for them and their dogs.

I have been thinking about the Mini Sprint-T and the scale mockup for the TGS2 as they both need a body. What I have been thinking about is making a mold off of the AMT kit body then casting a plug from Bondo to use making a vacuformed body after making the desired body modifications to the plug. The plug would then be split in half to draw the body material over to a form with no undercuts so the body can be removed easily from the mold. The TGS2 mold would have the rear hatch molded separately so it can be hinged to work on the engine and I can test side versus top hinges for access to the rear suspension and engine.

Still thinking about making the little V6 run on E85 only. There is a hypereutectic piston I can use that is flat topped and can be zero-decked for the minimum clearance between the head and the piston, and then the heads will have to be angle-milled to shrink the combustion chamber in the head without taking too much material off the bottom of the head. And I realize that the preceding sentence read like technobabble to about 90% of my readers who were not brought up hard-core gearheads, but every word was a valid technical term or connecting word between. IOW it was all English, just not a common dialect of English. Translation: There is a cast piston made with a low expansion rate high-strength aluminum alloy that is flat across the top and can be fitted flush with the top of the cylinder. Then the heads will have to be milled on an angle with more taken off on the big side of the combustion chamber to get the chamber as small as required with the least amount of material removed. Hypereutectic pistons can support about 375 HP on gas for this engine, and I’m only hunting 225 to 250 HP with cooler-burning E85 so well within estimated stress limits, plus they are inexpensive especially compared to forged pistons. In this case that is especially true because forged pistons would have to be custom made, they aren’t available as regular production items.

The last sentence of the previous paragraph pretty much sums up my biggest frustration with this build, almost everything is $pecial order or cu$tom made, especially in the engine. Some of that is because there were no performance applications for this engine aside from the 1991 Shelby Can Am series which only made 150 engines putting out about 225 HP. The other reason is the last one left the production line in 2011, 6 years ago. Compare this to the ubiquitous SBC that was in production as a factory-installed engine from 1955-2001 and is still in production as a replacement engine for emission controlled vehicles of that era, and as a crate engine for new cars that are not required to meet emissions controls like the Sprint-T. There were literally tens of millions of SBC made in dozens of different sizes from 265 to 455 cubic inches when you include the hybrids made from mixing different blocks and cranks. One of those hybrids actually made production status as the Z28 302 in3, which was a hybrid of the 283 crank in a 327/350 block. One of the most popular hybrids is the 400 crank in a 350 block bored 4.030″ to produce 383 in3. How popular is it? There are now twice as many 400 cranks as there were 400 SBC engines made, the aftermarket is producing brand new cranks with the 3.750″ stroke of the 400 crank with the smaller main journals of the 350 block. It’s even easier to get parts for the LS/LT engine families than it is the 3.3/3.8l Mopar V6.

And that’s enough kvetching about the free engine I was given, at least stock replacement parts are cheap and easy to find because of the millions of them on the road. And some of those factory parts are suitable for use in a high-performance engine with a little preparation, like balancing or grinding off flash and light polishing to remove stress risers.

And I have to go now because my friends on the Gulf are finally starting to check in and I don’t want to miss any. Also my back is starting to hurt again. I did pretty well for several hours today but the pains are back.

I’m melting, melting, what a world…

Heat indexes have been off the charts lately, from what I can tell. I haven’t been able to go for my walks so I have been spending most of the time indoors and hardly check the weather, but it’s 86°F in my office as I type this with the AC going. So it can’t be anything but hot outside. But just FYI my phone says it is currently 98°F outside. At 1855. So by deduction it must have been over 100 at some point today, say like between 1400 and 1500. ETA the 2200 news weather report had a 100° high temperature. And the urban heat island effect keeps the nighttime temperatures up, too. And this is where today’s headline came from YouTube

I’m not happy with the way the floor came out for two reasons. Number one is I forgot to include the front support for the front fenders, and 2) I made the rear cutouts too wide, as shown in the pictures. Seriously I left enough room for a 16″ wide tire and the widest race tire I have been looking at seriously was 14″ with the street tires in the 12″ range. And I have plenty of raw stock for the floor, finally. So the floor will get a do-over. And that’s why those 9″ wide tires in the pictures looked so lost in there. Even the 10″ wide tires for the Mini Sprint-T would have been swallowed up.

While I am on the subject of the TGS2 I have been looking at a pull-rod spring instead of direct mounted springs for 2 reasons. One reason is I can change the spring rate just by changing 2 bolts, either a little or a lot, The second reason is the unsprung part of the pull-rod is much less than the direct mount spring because the entire spring and shock are moving with the car. Yes they move with the axle but they are entirely supported by the frame so they are sprung weight. The bellcrank and mount add a couple of pounds but it is all sprung weight. But the primary reason to go with the pull-rod springing is adjustability, I can change spring rate and ride height in just a few seconds and swapping a different length pull-rod is much cheaper than swapping different shocks and springs. Literally a dollars to donuts comparison, I can buy or make a custom pull-rod for about the price of a dozen donuts where a spring and shock absorber are $200-300 assembled. With my budget this is a cost-benefit ratio I can most definitely live with.

And I need to take a shower and hit the hay.

Still working on the spindles

I spent hours working on one bushing last night and it still won’t take the kingpin. It’s getting close but won’t let me slide the pin through the bushing, and I have 3 more bushings to go after I finish that one. Either the stones are worn out or these are very hard brass bushings. I think they are actually bronze rather than brass, but still, not supposed to be that hard. I was using cutting oil and everything so unless the stones are worn out already from the axle boss I’m at a loss.

Moving on to the scale mockup TGS2 I found some more card stock to use for the floor. There was an expired TGIFriday mailer under my computer that was printed on extra thick stock. I have revised the clearance cutout for the front tires, so now all I have to do is find time to cut it out. I think if I skip a day blogging I’ll have the time to do a couple of floors, maybe?

I’m going to have to switch to my backup scale bucket body because I have already modified my first one to build the Mini Sprint-T. That means I have to open the chopped T-Coupe rod model. I really haven’t decided what I want to build from that one. There are so many choices… And I have really no time to build models. Models from boxed kits that is, mockup models are required for, reasons.

And because I need to get to work on something I’m closing this one down now.