LocostUSA.com

Yo Lonnie-
All good resolutions, ones I should make myself. Only reason I don't use metric is that, as you alluded to, I can't visualize in metric. How long is it? About a quarter inch. Got it. If you say it's 8 mm, you better hold up fingers to show me what you mean. Old dogs, new tricks, etc, etc.

Cheap tools? Even good ol' Sears Craftsman stuff is now mostly made overseas, and can be of dubious quality. (So far, their sockets, wrenches, etc are still good stuff. Power tools, not so much. Damn.) Harbor Freight? Consider 'em throw aways. If they get thru the job at hand, you're lucky. It's sad that the American consumer, me included, even goes in that store. Oh well...

As for #3, well, welcome to the aging process. What were we talking about? And where did I put my G#%&*mn notebook???

Happy 2012, Lonnie!

JDK

Thanks for the good wishes in the new year Keith and JD.

It's a really slow day and not much I can actually do in the garage. Here's the final table about 60% final welded with all elements placed and tacked. It is super strong. I'm walking all over it to get into the various bays to weld and it is really stiff even though not completely welded. I'm not a light weight, but it does not move in the slightest. That's what I wanted and that's what I got. I think I could probably put a Caddy Coupe de Ville down on the thing if I did it slowly enough.



My one concession to ready-made H/W is from the McMaster-Carr catalog. I though these leveler feet were pretty slick and would give it a nice professional look. The bolts are 3/8" and the fitting that goes inside the RHS will take 1,000 lb of weight (way more than enough) although the feet take less than that. Don't know what the RHS will take, but much more than I'll load on it.



All-in-all, not a bad first project since it's been a whole lot of years since I built anything in steel. The Locost chassis isn't a whole lot more complex than this.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

I think the chassis is less complex than that beast of a build table, nice work!

[quote="GonzoRacer"]Yo Lonnie-
Cheap tools? Even good ol' Sears Craftsman stuff is now mostly made overseas, and can be of dubious quality. (So far, their sockets, wrenches, etc are still good stuff. Power tools, not so much. Damn.) Harbor Freight? Consider 'em throw aways. If they get thru the job at hand, you're lucky. It's sad that the American consumer, me included, even goes in that store. Oh well...

Yo JD:
Last time I drove my spec racer (avatar) it was at Fontana super speedway road course and pitted next to a Snap On dealer...... This was 5+ years ago!! Even he was lamenting the imports they were getting from overseas!!! China (If memory serves) was getting involved with certain items in their lineup!!!! It is a sorry state of affairs..... n' I don't imagine it's gotten any better!

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McSorely 442 / SBF - track day, autocross, street licensed toy. Build in process.

Hey Lonnie:

Under the FWIW column: You might want to consider a bit more strength on the end sections. Not needed at the moment but when you start mocking up the real parts, the weght of the motor, differential, tires, suspension does add up and likely to be concentrated at the ends by blocking the chassis up for trial fits, etc.... Just a thought. Otherwise, as far as I can see it resents the bar for work tables !!

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McSorely 442 / SBF - track day, autocross, street licensed toy. Build in process.

Hi Monte,

Happy New Year to you and yours.

Thanks for the interest and the comment. In the photo just above, the front of the table is closest to you as you look at the picture. It isn't at all obvious, but if you look back on page 13 of my build log you'll see a 3D model of the chassis sitting on the build table. You'll recognize the pads for the motor mounts in the 3D model. They sit right above the front truss and the weight on those pads is taken directly into the legs through the truss. The only weight forward of the front truss will be the radiator, a small part of the chassis, front suspension, steering and sway bar plus the nose cone and horns and a few small items. It's a pretty light load, all-in-all.

The middle truss is just behind the transmission mount and right under the (B2 or BR11) cross member. So, a huge majority of the mechanical components including most of the chassis weight, dash, steering column, engine, transmission, etc., is between the first two trusses. That's why they're stronger. This is really a combination build table/chassis bench and I intend to assemble the entire car on it, cutting away the plywood as needed once the basic chassis is done, and aligning the mechanical components while doing so. The longitudinal trusses are open enough to allow me to squeeze through from the sides or alternately go from the back to get underneath and work.

Between the middle and last truss, it's almost all the rear half of the tunnel, cockpit, driveshaft, seats, etc. That is, not all that much of a load. The 3rd truss is directly under the B1 (Book) or BR12 (Haynes) cross member. The only things on the rear cantilever section, aft of the 3rd truss, is a small percet of the chassis and seatback, the rear axle, chassis kick-up (light tubing), gas tank (empty) and the rear aluminum bodywork. Perhaps in all 325 pounds, worst case. However, I'm planning to make some temporary "jack stands" of wood for each of the rear wheels to sit on when attached to the rear axle, so I can play with the ride height while I do the mechanical alignment. I think the real weight on the cantilever section will be less than 200 lb., except for brief periods of time.

I also have in mind that I'm going to build a second chassis at a later point, but not for the street. That's why I'm willing to make the investment in a semi-permanent structure now and will probably sell it to someone else building a Locost after I'm done with it.

That's the hope and the plan anyway.

Regards,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Gottcha! Boy have you done your homework! Makes for a very pleasant project! I am really interested in your build and sure to learn from it! I'm not nearly as detailed as you are and tend to "wing it" a bit. Part of the McGiver in me I guess and also bad habits!!
Do wish you and yours well in the new year.

Best, Monte

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McSorely 442 / SBF - track day, autocross, street licensed toy. Build in process.

a high tech build table if ever i saw one,

when i built my car, the only problem with the build table was width, i could have used some width so that i could install the suspension and steering to work out all the geometry, toe changes, roll center etc. in the real world actually leaning the chassis to see the effects from side to side and front to back.

perhaps you could make add ons where needed.

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this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

Thank you.

I don't yet know how I'm going to handle mocking-up the suspension, at least at front. The rear will be very simple. I did consider making the table/chassis bench capable of doing that, but really didn't know what I'd need to have and where it should be located so, I'm leaving that as a future task.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Oh Lord, I've got a new toy. Like I really need another task or distraction right now - NOT. But, this one is fun and it really is something essential. Here's a screen shot:


I have a few design tasks left to do like the front and rear suspension, dashboard hoop, steering setup, pedal box plus other smaller details like the emergency brake mounting brackets. However, I knew those could be completed after the basic chassis design was finished and while the first stages of construction were underway. I know what I'll have for suspension types (SLA front and 4-link with Panhard Rod at rear and anti-roll bars front and back) and I bought a program that permits me to design, simulate and link (couple) front and rear designs together plus animate their movement, capturing dynamic values while doing so.

Completing the final suspension design is probably a few months away. These suspension programs are so complex and have so many variables that I knew the learning curve would be steep. The variables shown (both input and calculated) in the above screen shot are only about 20% of whats available and accessed by using the scroll bar in the lower window. That's why I'll be trying out sample designs at night now while doing practical, basic construction work in daytime. It's going to take some time to get competent with this package.

This program, Suspension Analyzer 2.4, does not have eye-catching visuals. The graphics are simple, but, man, it has every variable know to suspension design and can calculate just about any dynamic (variable) value you'd wish to know. I'm very impressed so far. The animation feature is super impressive. It visually tracks things like roll centers right, left and combined while varying dive, roll and steer per your design particulars. Those are the colored dots in the screen shot with the initial and dynamic positions shown for each increment or step. The dotted lines indicate the initial, usually static, position. It's totally cool and a wannabe suspension wonk's dream. You can save multiple setups for any basic design and print graphs and reports to compare their changes over a range of motions in critical areas.

My first task has been putting in the values for my Locost into a sample SLA design provided with the software. I did discipline myself to create a specification document, and in that capture essential design information like estimated all-up weight, weight distribution F/R and R/L, track, wheelbase, tire sizes and all tire particulars such as tread width, rolling radius and so on. It made it easy to plug things in and run a simulation. I'm going to use the control arm lengths of the Book and Haynes Roadster at first, but will eventually optimize for my own donor parts.

I'd better make a new pot of coffee. I'll be up late tonight!

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Arghhhh! --- @*&#!%$^@^&*

There is a lot to learn about welding these 3D space structures. In lesson 1, I learned to appreciate the pull too many tack welds can have on an individual member, taking it right out of square. In lesson 2, I have learned that the effects of welding such a structure over a nine foot length, even if you do your best to follow the welding rules that minimize distortion, can mean a half inch variation or more. Sugar!

I think the way I supported the table (at the very ends) while building it contributed to the problem. I should have done a better job of supporting it all along the way and particularly at the main cross members where most of the weight and welding stresses lie. I also think I overestimated the ability of the 14 gauge side rails and cross members to support the weight of the completed structure and absorb welding distortion. “Live and Learn”, as is so often said.

So, anyway, after a trip to my local Shims-R-Us store, I’m now getting the plywood top as flat as possible on the build table, which in all other ways turned out better than I expected. If I’d have known how pretty a good coat of paint would make my ugly welds look, I’d have done a lot less grinding on them. It would be nice if the plywood top was perfectly flat, but that will be tough as the natural moisture of winter has taken up residence in the plywood even though it’s been stored standing on edge inside my garage. There is a little waviness in the top surface now. How flat is flat enough, I’m wondering? Even the RHS tubing itself isn’t perfectly straight.




Another reason I haven’t done much lately is my unhappiness with the accuracy of the angle cuts I was getting in the RHS steel. The horizontal bandsaw proved too difficult to set up for angle cuts. The 14” abrasive cut-off saw was woefully deficient. Its built-in vise tends to loosen from vibration when you’re cutting the blades themselves wobble producing uneven cuts that require a lot of file work to fix. I’m not that good with hand cutting using a hacksaw and I’m way too old to cut out every member by hand anyway.

I knew in my heart of hearts the solution was to find a suitable vertical, metal-cutting bandsaw and learn to use it well. A query to Slappynuts who (a pro fabricator by trade) confirmed my gut feeling. I elected to wait until I could find an affordable second hand unit before cutting more metal and making the chassis itself.

Below are some photos of my used 220V metal cutting unit. It came from a young guy who set up his own small shop to make tattoo machines, but lost interest in the product. He hadn’t set it up properly, when he assembled it, but he also hadn’t used it long enough to screw things up permanently. I went through the rather outstanding manual from the manufacturer and used their technical support line to get it operating correctly although it did need new blade guides and one new guide bearing. It is so effective and fast at cutting steel that it’s downright scary. I’m thinking I’m going to get some of those chainmail gloves that butchers wear. This thing could take a finger off in a heartbeat.




By the end of next week I expect to have my customized version of the Haynes chassis laid out on the build table and be cutting and tacking actual chassis steel. Now, I'm wonder what lesson 3 will be?

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Yo Lonnie-
Nice looking bandsaw!!! I've used one of those a few times, they do cut metal straight and true and do it quickly! (and yes, careful with those fingers!) That would have been my weapon of choice for cutting chassis tubing, but I didn't have one. I got by, but it will be so much easier and better quality with that l'il jewel! Well done, Sir!


JD

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JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom

Nice bandsaw Lonnie..i just love that work of art ..that is your build table..

KIWI Dave

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I USE TO HAVE AN OPEN MIND ..BUT MY BRAINS KEPT FALLING OUT

Hey Lonnie! First class saw and table! Now the fun stuff begins! Looking forward to following your most miticulous build!!

Congrats!
M

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McSorely 442 / SBF - track day, autocross, street licensed toy. Build in process.

Have you got a stick of lube for the blade? Don't run it too fast, steel takes awhile to cut at the proper speed. Though there is not much material in 16 gauge material.

Wait till you use that thing on aluminum, you'll be wanting to carve billet engine blocks next!

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
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