Need ideas for a desert buggy mod
 

I've never tried something like this before, so I figured I'd start by asking for ideas & tips, then decide if it's something I really want to do...

Basically, I absolutely love the look of losi's mini desert buggy. Cool as hell.

I also really like the slash's I have... and I started thinking about what it would take to turn the slash into a desert buggy. I'm not talking a backslash look, but a roll cage with flat body panels look. I think it could be done, and could be really cool if done well... but I don't know where to start.

Should I look into brake line for the roll cage, and bend/weld one to tack onto the chassis? Ideas for the body panels? Other thoughts I'd need to consider?

Right now both slash's are stock (they're for the kids mostly), but I think I'd switch to a decent brushless setup, put some paddle tires on the back and some knife edge looking ones on the front.

I dunno, what do you all think?

Tony

This would be my inspiration: http://twitpic.com/m8sqw http://twitpic.com/wkrx8

(Paul Tracy's Dune Buggy)

i wouldnt use brake line on a slash for something as complicated (and eventually HEAVY) as a buggy.id go for something like ABS tubing or rod and heat and bend it into shape,much lighter and plenty tough for a lightweight slash. and then use either ABS or styrene (or uber expensive carbon fiber) for the panels with zip tie or small straps for panel attachment.just my .02--josh

4 person
http://www.rc4wdstore.com/2/product_...cb3a5d81dd611c

2 person
http://www.rc4wdstore.com/2/product_...roducts_id=490

if anyone EVER sees one of these FS for less somplace else, LMK ASAP

Those chassis are awesome.

Where could I get ABS tubing/ ABS rod?

i get alot of mine here.cheap shipoping,great products.--josh

http://www.rplastics.com/plastictube.html

Was looking around, found this place, too. http://www.indplastic.com/

What kind of plastic would be best for making a roll cage out of? ABS? Delrin? Something else? I'm assuming it'll be something I can heat with a torch (briefly) and bend. I'll probably make some sort of mold/form for each part, to keep them consistent.

And what thickness? .25"?

Ordered a bunch of ABS & Delrin to experiment with.

sorry id didnt respond quick enough,the ABS is probably your best bet.it can be heated and painted along with the fact that if you glue anything together or try to melt anything together the delrin will crack and break.--josh

Ok, good to know. I only bought $5 worth of delrin, so no biggie there.

Delrin would work great for skid plates if you go 1/8"+ thick.

I'm mostly going to focus on the roll cage to start, and just build off of the slash chassis.

If that turns out to look like poo (which it probably will) I'll start down the road of the bigger mods. lol

Do yourself a favor and cut a form out of plywood or something to bend the plastic around. That way everything will be symmetrical and line up properly.

That was the plan, yeah. to make some forms and keep them. That way if I decide to refine the design later, I'm not starting all over, either. Should be a good learning process for me, at least!

There will certainly be some trial-and-error involved. Hopefully more trial than error. :lol:

Yeah, I'm really not sure how I want to actually form it - overall shape / size, where it'll be best to put the joints, etc. Should be interesting! I've also been looking around on google for more RL pics of buggies for design ideas. I have no clue how well all of this is going to work out - never done anything like it before!

Got my plastic today, going to go grab some thin metal rod to form a prototype out of, and some wood to form molds out of. Made some good plans for how to do that.

Got the slash stripped down to where I want.

Doing some rough designs on paper already, I think this will work out nicely.

Did a test run with the plastic, bending the abs rod is simple enough. Going with the .250" abs (also got .375, that's a bit too thick) and some delrin (test bends on that aren't done yet, but I don't see it working as well).

Got a few different thicknesses of plastic sheet, too, for the body.

Tony

cool! cant wait to see what you come up with!--josh

Here's the first mock-up (using electrical wire and painter's tape).

I think the cage could be at least the diameter of the front bumper, and still look scale.

Also if you get thicker material, you can heat it up and flatten it, then drill it. Would simplify end mounts and intersections for the cage...

Edit: I see you got 1/4".. that or 5/16" would be fine :yes:

Yeah, I'm going to start experimenting with the abs next - the above photos are just a first run mock-up. Got a long way to go! I may need to order some more abs, too.

The big questions I'm hitting are where to put the joints/welds as I build in order to get the toughest structure for rollovers. Though I think the body panels will add a lot of stability to it as well. The plan is to attach them with zip ties.

Tony

Got the first two pieces bent, bought wing mounts & a wing. (Not positive I want a wing, but trying it out for now) Testing out different methods of gluing the abs to see which gives the best result (plastix weld, epoxy, gorilla glue, and some other superglue like plastic bonder)

Need to find some tires & rims. Want sand paddles in the back, and smaller thin razors (I think they're called that?) for the front. Hopefully with some good stagger in size. I hate trying to find the right tires & rims to fit rc's, lol.

The bending went really well - they're not identical, but they don't look bad to me! (Bent the outer two rollcage pieces that would go around a driver, used the .375 abs). Going to do the rollcage out of the thick stuff, and the rest of the cage out of the .250" abs. Should give a good look, and a solid build.

Biggest questions are how to do the joints, and how to attach it to the chassis. I'm playing with a few different options on both.

Tony

For ABS I believe normal plastic model glue will work. It basically welds it together so I doubt it would break apart in a crash. This is the stuff. Once it hardens it's like one piece of plastic.

I'll give that a shot - none of the ones I've tested so far worked... at all.

Finding things online that say you can use acetone to melt the abs together into one solid piece, going to experiment with that.

I think that's the active ingredient in the plastic model cement...

Looks like a couple of their cements will work for ABS. http://www.testors.com/search?q=abs&x=0&y=0

More experimenting to do! Thanks!

Good luck!

Got the model cement & a plastic solvent / welder applied & set, and gonna let them go overnight.... be interesting to tell which bonds better. Both look to be doing great so far!

The solvent was the clear winner - both melted the plastic to some extent, but the glue for the Testor's plastic cement didn't really help it bond. The plastic weld just literally melted them together. I was able to seperate both, but the solvent took considerably more force. I think with a better fit (I was just using scraps I hadn't tried to shape to fit nicely together) it will bond completely, and not be easily breakable at all.

So, a total of 6 glues tested, now to move on to some real building!

Remaining challenges:
1 - precise design - I have the general layout, gotta get down to the specifics!
2 - How to join the rollcage to the chassis. 3 things in mind here - 1, for the thicker center cage, putting holes in the chassis, drilling a small pilot hole in the center of the .375 abs, and running a screw up into it. 2, flattening the ends of the .250 abs, and drilling holes through it to attach it to the chassis with nuts & bolts. 3, using round end electric wire connectors which fit over the end of the abs, gluing those, and then bolts through the round end connectors to the chassis.

At this point I'm favoring 1 & 3. They're more precise, and have a cleaner look.
Tony

For the heck of it, I tried out some pure acetone, which definitely just melts the abs... but the bond was no stronger then the Plastic Weld. I had a bit of a brainstorm last night on how to attach it all to the chassis in an easy way, that's field-serviceable. Also had some ideas on how to improve my bending, for greater consistency. Hopefully I'll have time tomorrow to cut & shape more of the roll cage.

Isn't progress great? Pics are better though... :lol:

There's not much to take a pic of yet, lol! If I get the main rollcage together and on the chassis I'll put up some good pics of it for critique.

Haven't updated this in a while, because it was just sitting on a shelf. Finally took the time to do some build and assembly. Pics here:
http://sites.google.com/site/kraegar/rc

I should the cage build done today or tomorrow, letting it dry some now.

Then time to cut the panels and attach them, and attach it to the chassis.

After that it's just getting tires & wheels (probably prolines) and a brushless setup for it.

Then time to find some sand!

Looks pretty neat. I think remote reservoir shocks would look awesome with the reservoirs mounted horizontally on the side chassis tubes. RC4WD used to have them, but I just went there and couldn't find them anymore.

That looks great Kraegar! Have you done any informal strength testing on those acetone welds?

I don't know, but this is a new trend and I like it more than CORR!

http://kyosho.com/eng/products/rc/de...duct_id=106257

Awesome build by the way :)

I did lots of testing, and finally found what I think is the strongest weld I can get. I start off by using Plastruct plastic weld (glass bottle, orange label, bought it at the LHS, this stuff http://www.kitkraft.biz/product.php?productid=1418) to set the basic joint. Let that dry for a minute or two, so the pieces are connected how I want. Then I "paint" the abs on around that in thin layers.

This is fairly strong on its own, but will break if you use enough force. That's OK! It breaks because the ABS gets little air bubbles in it. If you use the plastic weld to fix those breaks, it fills in the air bubbles, re-welds the abs, and becomes nearly unbreakable. It's kind of crazy how well it works.

So yeah, I fully expect some major breakage on my first big crash, but I know ahead of time that the fix will actually make it stronger. Took a lot of trial and error, but I'm really amazed with the welds I get. Was very worth it.

Tony

Hadn't seen that kyosho before, pretty cool.