Thinking about making a custom chassis

[neamerjell]

I would like to know people's experiences with making their own chassis and out of what materials they made them. I have heard a lot about Delrin, but I have no idea where to get it in Cincinnati, Ohio. I was thinking that I could use a heavy gauge Plexiglas, they sell that at Home Depot. I figure if I get a heavy enough gauge, I won't have to worry about it flexing, but how heavy would I need to go to achieve the rigidity required?

Experiences, ideas, good, bad, all welcomed.

I am looking to make a Crawler King into something compatible with Axial parts, namely their bumpers. I'd also like to retain the Crawler King's original wheelbase of 12.5 inches.

Also, I do have access to a workshop containing a band saw and drill press, and I'm experienced with them. (Which is partially why I thought of Plexiglas)

I'm also trying to find a LOW COST way of doing this. So that rules out custom tube chassis - at least I think it does, I don't have any brazing materials.

Would I seriously be better off just buying a $40 off-the-shelf Axial chassis and modding it to my King's parts? I know I'll need a motor clocker plate to do this.

[oldhippie]

Go for it. I've built a bunch of chassis out of cheap alum 16/20 gauge sheet. They hold up fine with a few cross braces. When I get one I like I'm gonna make it out of delrin. For comps I run a store bought one.

[Jkelley]

I say go for it too. I believe the most important part is making sure the two halves are Identical. If you Have holes in one side and they arent the same on the other side and your links are the same length, it'll be like a bird with one wing. Just going around in circles

[neamerjell]

There is a trick my dad taught me to solve the whole both sides being the same issue - double stick tape.

Take the double stick tape and put it between the two stock pieces of whatever you're using, mark the outline and the hole positions on the top piece. Then cut and drill both pieces at once. (Drilling first might work better, more to hold onto and less chance of the drill press grabbing on and spinning the whole thing - been there, done that... words of experience, people!) This trick works great on wood, and should work on anything able to be cut with a band saw.

[neamerjell]

What material to use and what thickness?

If I do go with Plexiglas/LEXAN/acrylic sheet, how thick should it be in order to hold its shape and not bend under stress?

What are people's opinions of the materials they used?

I think it might help to mention that I want to avoid metal. I thought of Plexiglas first because it was relatively cheap and easy to work with.

[silentcircus]

Originally Posted by neamerjell

What material to use and what thickness?

If I do go with Plexiglas/LEXAN/acrylic sheet, how thick should it be in order to hold its shape and not bend under stress?

What are people's opinions of the materials they used?

I think it might help to mention that I want to avoid metal. I thought of Plexiglas first because it was relatively cheap and easy to work with.

Plexiglas may be too brittle for a chassis. I've used it for snake cage doors and other applications and it doesn't really take well to being dropped or drilled. If you do go with it use a high speed drill at a slow rate of drilling. If the bit binds up the plexi snaps.

A trick I use, similar to the double sided tape without the mess, is to drill two holes on opposite ends, outside the finished product's area. Bolt the two pieces together and then cut. When you get down to cutting the plates out just move the bolts to a couple of the mounting holes on the chassis.

[BobP]

Silentcircus is right , plexi, lexon, acrilic is way to brittle. You might be able to work with it but it will come apart on the rocks. I too started with a crawler king, my friend you have your work cut out for you. The steering set-up is junk for rock crawling, not responsive enough, the C.G. is way to high so you rebuild the chassis only to find out the shocks are to long. Tear your battery pack apart and make a saddle pack out of it and put it on the front axle on either side of the servo mount you fab for your new servo. The motor clocking plate , servo mount, steer linkage, upper and lower links as well as the chassis you can fab yourself. Buy
a pad of layout paper grab a scale and a pencil and get it on paper first.
Any real hardware should have alum. sheets in 6"x12" or 12"x12" my local
hardware can order Delrin as well. I know this is a lot of work and you want to keep it simple, but if you want to crawl and climb its gonna take
some work. Oh and pick up a set of soft Rovers when you get your shocks

[neamerjell]

I have front and rear steering on axle from East End Machining, Hot Bodies rover tires, Axial beadlock rims, the crawler kit, the gear reduction kit, and a Traxxas TQ 4 channel radio that I modified to provide rear steering on the 2-position toggle switch (I switched the channels from the red rocker switch to the toggle switch). As you can see, I'm halfway there.

I've been seeing chassis made of Derin all over this forum and I would really like to know where I could get some in Cincinnati, OH, since that has the required strength, and from what I've read it is easy to work with.

I Googled it, and all I've found so far is huge 3/4" thick sheets of it for obscene prices.

[es79]

Pretty sure you can get it from McMaster Carr. Also I heard some people use cutting board material? I dpn't know about that one though.

Originally Posted by neamerjell

I have front and rear steering on axle from East End Machining, Hot Bodies rover tires, Axial beadlock rims, the crawler kit, the gear reduction kit, and a Traxxas TQ 4 channel radio that I modified to provide rear steering on the 2-position toggle switch (I switched the channels from the red rocker switch to the toggle switch). As you can see, I'm halfway there.

I've been seeing chassis made of Derin all over this forum and I would really like to know where I could get some in Cincinnati, OH, since that has the required strength, and from what I've read it is easy to work with.

I Googled it, and all I've found so far is huge 3/4" thick sheets of it for obscene prices.

[gdhknives]

Check your area phonebook. That's how I came across our local plastics dealer. Delrin is hard to beat for this purpose. Above all keep pushing forward.

[guywithhat]

i used a cutting board from walmart.. is holding up good... and if nothing else.. you can use it as test material before you cut up yer good plastics...

[lowandslow2]

thats what this game is all about building it with whatever you got and then kicking ass with your homeade rock stomper

[neamerjell]

I too have seen the Walmart cutting boards in these forums and have seen them used for prototyping... But, are these the cutting boards for kitchen use or sewing use? I have seen some boards for sewing use and cutting fabric and I thought they were flimsy. Of course these were four foot square 1/8" thick boards. Surely these are not the ones being used, are they?

[RIG_RIDER]

Cutting boards for kitchen use is what you would use.
Take some time and hit the search function, you will find others have ask similar questions and have received many replies.

[neamerjell]

The search's lack of specific results I was looking for is what led me to start this thread. Maybe I was too specific in my search terms... I've experienced similar effects on Google: pinpoint search = 0 results, slightly more general search = small selection of related but not quite useful information, general search = tidal wave of completely irrelevant information.