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Most mid engine sand cars have the drive axles facing the same direction as rear engine sand cars. I was concerned with my, possible build, being the opposite direction of the norm. I do not think it would be a problem, however, after seeing the same drive axle configuration that I was considering, functioning successfully on most SXS's.

Decisions, decisions. I know what you mean. Never done!

No comments regarding my homemade bolt in spindles?

Devastator wrote: ↑Mon Nov 09, 2020 10:46 am Most mid engine sand cars have the drive axles facing the same direction as rear engine sand cars. I was concerned with my, possible build, being the opposite direction of the norm. I do not think it would be a problem, however, after seeing the same drive axle configuration that I was considering, functioning successfully on most SXS's.

Dev, with the way the CVs work the only possibility of having problems would be of having a shorter wheel base .

I noticed the bolt on spindles which I don't remember ever seen this being done before. Usually they and the mounts are cast as a single unit then machined to tolerance. Any drag on the bearings in the wrong direction might/could be a problem but then this is just a guess.

Lee

In order for me to cast and then machine my spindles, (the frames in particular), I would have to do so out of aluminum. Instead, I machined a plate that was welded to the rest of the spindle frame. I machined this plate to receive the threaded spindle and have a lock nut on the inside as a retainer. The bronze part is this lock nut. I also made a tool to tighten the lock nut, but didn't post a pic of it. I cut some new spindle frames to weld the machined plate to, but screwed something up in the design as my heims now have the tires locking them up when I assemble it. Damn! So, I cut out the original plate with the spindle welded to it, and welded the newly machined plate in it's place. I now have 1 trip to the dunes on this assembly and it's working well. I should note that I only replaced one of the plates in the spindle frames. I hope to have enough time to replace the other one after Thanksgiving. I'm also considering changing the suspension from heims running "horizontally", to running them vertically like a Uniball, or maybe machining a threaded Uniball? I'm not sure yet.
I replaced my front rims, since I had a horrible crack running the circumference of one of them, (probably started when I broke the spindle). I also replaced the "worn out completely 3 years ago" rack and pinion steering box. Now, instead of having a random 2" toe in to toe out change when I hit a bump, I only have 1/4" toe in and toe out. Off to the dunes tomorrow and hoping everything stays together.

One of the things that bother me a lot, which is why I bring it up at times, is the way of making the threads on both fasteners or on parts. Again, I am not an engineer but what is now referred to as a "Tech" (which covers a large area) but I had to sit/stand (mostly stand back) while a lot of multi-person discussions went on at my drafting table about designs which meant several types of engineers (and specialists) and others that were concerned about a (new or existing) design. Threads often ended up as part of the conversation; usually they dealt with the way the threads were made and this was for various strength reasons.

For the discussion: https://www.bing.com/search?q=the+diffe ... e6cb58b99b

Stock that is to be threaded usually has had great care in getting the material's grain going in one direction but it is the two basic ways of making them that makes a difference. The more common way is/was to cut the threads either on a lathe or by using tap and die. The problem here is that you cut part of the grain away so the threads have lost some of the strength of the stock.

When rolling the threads the material' grain is compacted (squashed) at the bottom of the thread but not removed. Most bolts are rolled now days but not sure about the nuts and how they are done as what I was working on dealt mostly with, when necessary, the design/use of bolts and studs. The threaded receptacles' were usually in another part of the discussion.

Again, this is why I brought it up, not picking just trying to help. Jam nuts are good and their use is good which is not a problem with me.

Lee

Thread rolling, (sometimes called "thread whirling"), is a very common practice in modern industry and produces a stronger thread than thread cutting does. Thread rolling, however, does not lend itself to my parts. I threaded them on a CNC mill, with a 20 TPI carbide thread mill, programmed to do a helically interpolated bore. The spindle shafts, alternatively, were threaded on a CNC lathe with a single point, carbide, threading tool.

Is your machine CAM controlled?

Lee

Are you running stock gears in your 091?

Stupid SPAM filter doesn't like the STF.
Lee - the machines I program are CNCs. I use a CAD/CAM system to program them, but CAM is not integrated into the machines. that dais, I programmed the helical thread interpolation by hand with a calculator.
Leather - No, there is nothing stock about my 091. I had it custom built with Weddle gears, from Dan's Bus Box in Phoenix.
2 days ago, the thumb drive with all of the bolt in spindle information on it, crashed as I was backing it up, (naturally), and I lost most of the info. The only upside is that I still have the parts and can reverse engineer everything to write replacement programs. Still...it sucks!

OK I am biting on the thread in spindle. Obviously they are a nice piece of machining. Whats the overall concept/idea here? Replaceability? Or not actually welding a spud and having to heat treat after? What gives, lets hear it?

"Lee - the machines I program are CNCs. I use a CAD/CAM system to program them, but CAM is not integrated into the machines. that dais, I programmed the helical thread interpolation by hand with a calculator."

The terms "CAD" and "CAM" are so often miss-construed/used interchangeably now days; it often turned out that people would use the term CAD when they were working with CAM (kind of like the old "pattern makers" did with engineering designs so the individual parts could be made). I worked in/with CAD off and on since the late 70s (using several different CAD programs) but CAM was not fully ready for the full interplay then. Not too long before I retired (20 years ago) the full CAD to CAM interplay had finally been achieved mostly due to the problem that CAM had not been ready for the 8-axis milling machines. Waterjet and Laser jet cutting could be done with waterjet being the first. One of the things we used the waterjet for was to cut carpet.

Things are still being added to the CAD/CAM process so I am not up-to-date as I was as my last assignment was to work with additional engineering updates to CAD... more of a cleaning up a lot of problems that had arisen in the company I was working for (we didn't get a lot of the problems cleaned due to an earlier mess up had gotten out of hand and couldn't be corrected).

Lee

We had a CO2 laser at work. 160 x 80 bed, 4000 watt. It would cut through 1" thick carbon steel, 5/8" thick stainless steel, and 1/2" thick aluminum. It was amazing to watch! This is a 3/4" thick carbon steel plate we were cutting.

That's a mighty thick part for a laser.
I like it!

So Dev how is the reverse engineering going?