Thanks Paul! Yup, I'm well aware of the tire size issue, and I've thought a lot about it. I figured I could either go with lawn mower tires (hard plastic, and a very harsh ride even with fully independent suspension as well as the difficulty of adapting to an RC driveline), some relatively expensive (and heavy) steel hubbed semi-pneumatic tires (and add a LOT of strain to the driveline due to their weight), or... (drum roll please) I found a niche RC market that has just what I was looking for: RC rock crawling. They have tires from as small as you want, all the way up to 10 inch monsters. For the purposes of scale, I think I'm going to go with RC4WD's 4.0 Rock Crushers. They're 8.26 inches outer diameter, and a pretty close approximation of the Michelin XZL: a common APC tire.
http://www.rc4wdstore.com/2/product_info.php?cPath=18&products_id=430 They're also fairly soft, as they're made for rock crawling: lending themselves to a softer ride and less impact on the frame (mixed with the suspension). On the down side... If you looked at the link I posted above, they're about $40 a pair. (Yea Gods! I can't believe I think I'm going to get away with that!!!). So, we're looking at around $120 just to put shoes on my beggar; but they are also admittedly the only stupidly expensive part of the build (as far as my simple brain has calculated anyway...) As to hard hits: I'm fully aware of it. As an ex-avid paint-baller, I've got the scars to show it. (big toothy grin) And so, I'm planning on building the basic framework of the monstrosity out of steel brakeline, brazed at the joints: probably something in the 3/4 inch range. I found a place locally that will sell 72 inches pieces of the stuff for $4 a length. I figure ~$25 for a cheap Home Depot brazing kit, and I should be able to patch together a rock crawler/baja rally style tube frame over a couple months for not too much. I get the light weight rigidity from a tube frame, plus the ease of repair as its been brazed together. >From there, I tack on some washers on the corners, and it's a simple matter of >bolting on the plate sheet metal (or fiber glass/newspaper-woodglue mache?) >skin. If we go the woodglue/newspaper route (which was an absolutely BRILLIANT >idea, if you're out there), and it proves not strong enough to hold up, I >simply unbolt (or cut it off), and redo with a layer of the thinnest plywood I >can find to add tensile strength. And I'm well aware of the disadvantage I'd be at given it's an armored car. Secretly, deep down, I'm hoping the light weight will give me a speed advantage. Soft tires, fully sprung suspension, and an AWD drive line should give me some impressive cross-country performance. I'm working off guestimates here, but some of the larger electric monster trucks have to speeds of 40+ mph. Granted, that is a MUCH lighter vehicle than I have planned, and that is going to only give a run time of maybe 10~15 minutes. But it does show what is possible. I figure if I can get a top speed in the high teens through gearing, and a higher torque motor than they run, mixed with 4~5 times as much battery capacity, I should be sitting well when it comes to the "Run Away!" part of the battle. After all: I'll be in it to have fun, and drive a cool AFV. I'm in it for the fun: not to be the baddest tank killer on the field. From: phil...@defnet.com To: rctankcombat@googlegroups.com Subject: RE: [TANKS] Complete Newbie... Date: Tue, 24 Nov 2009 11:09:26 -0500 Welcome to the group! I was looking at building a B-1 Centauro myself! I think you should keep a couple of things in mind. Firstly, others will be shooting paintballs at your vehicle. This means that your hull will need to stand up to some pretty violent impacts. Secondly, your wheels will need to be in the neighborhood of 8” in diameter. I don’t know much about monster trucks, but I haven’t seen many with that size wheels. Thirdly, anything that you strengthen after you start your build will add weight. I would suggest going big from the start. And, finally…. Have a look at the rules for an armored car. No matter how large the gun, no matter how thick the armor the actual vehicle has, an arored car will always be at a disadvantage. Good luck!!! Paul H. From: whitney james [mailto:me1y...@hotmail.com] Sent: Tuesday, November 24, 2009 8:06 AM To: rctankcombat@googlegroups.com Subject: [TANKS] Complete Newbie... Hey all! Been a lurker here for more years than my pride would allow me to admit, but I'm finally taking the plunge and beginning a build. To start off with, the site is about tanks. That much is obvious. However, I’ve seen a couple armored cars there, and I think that is where my interest lies. And so, I present the B1 Centuaro. It’s got a nice bulky body to fit all those moving bit’s that make it do cool things, as well as nice sloped armor that will (in theory anyway) make up for a relatively weak armor rating (25mm up front: upgradable to 30mm). However, it does come with a 105mm main gun, so that puts us into Tank Destroyer territory. (evil little grin) http://www.sbmodels.net/images/New_From/ModelVictoria/MV002/images/MV0002.jpg Yup: it’s wheeled. I don’t know why, but in a place beyond all reason, I find a wheeled vehicle vastly easier to engineer than a tracked one. I know: I have issues. Still, what do you do? Anyway. The site has made the comment that RC car parts simply do not stand up to the strains demanded of them in this sport. Well, being a complete idiot, I threw that advice out in favor of RC parts. My basic plan is to scrounge Evil-Bay and dredge up some Nitro RC monstertruck parts, and build my driveline/suspension system from that. The vast bulk will be taken from the Traxxas company, as they seems of a fairly reputable sort, and their T-Maxx and Revo trucks are both everywhere, and as any number of UTube videos will document, are nearly indestructible. I figure anything designed to leap 12 feet in the air, fly 25 horizontal feet, land on it’s head, and keep going is probably fairly tough. Additionally, parts can be had for fairly cheap, so there you go. As the B1 has 4 sets of wheels, I’ll need parts from 2 RC monster trucks. I considered merely buying two of them, stripping what I need and Craigslisting/E-baying the rest of the bits off, but at ~$200 a pop, that was a bit too much of an initial investment. I’m on a bit of a budget here, as my better (and wiser) half has authorized around $20 a month to be put into this thing so that option was out. As mentioned, I’ve taken the plunge and purchased (won) 3 bulkheads (mounts for the swing arms: 2 rear, and 1 front), some swing arm pins (enough for 2 axles), and (hopefully) a set of A-Arms (2 axles worth). Assuming I am correct: that their description of a “complete set” of A-Arms included 4 upper, and 4 lower, I will be in possession of the above mentioned pieces for the grand total of $35.85. This is about half my suspension system. “How to get the power to the wheels?” you might ask. Again, the commercial market comes to the rescue. I’ve seen differentials for the Traxxas Revo 3.3 going for around $10 plus shipping. Considering it costs 6 times that to build one from your local hobby shop, that’s on the menu for next month. In total, I’ll need 6 (to be spread over a couple months, obviously): 2 for the front and rear most differentials, and 4 to be cannibalized into 2 through differentials for the two middle axles. Now: Most of the tanks I’ve seen built on the website (Yes, I’ve looked through every page of every single one) don’t seem to take weight into account: building with materials such as solid plywood and steel. Note: I said “most”. (little winky emoticon) My goal will be to build as lightly as possible: hence the commercial nylon parts (and my lack of fabrication skills…). My assumption is (and yes: this may end up making an a** out of me) is that the lighter the vehicle, the less power will be required to move it. Also, as I only will have need of 1 power source… well, my logic falls apart there, but it seems like those two things should be complimentary. Less power requirements means less battery requirements means less weight means less power requirements means less battery… you get the idea. As a power source (remember, we’re going for CHEAP quality here) I’m planning on the tried and true drill motor setup. I’ve seen them tried on tanks, but the complains are that they just don’t have the power. An issue I hope to address with light weight. My plan is to find a trashed 18~24 volt variable speed cordless drill (preferably with a 2 speed planetary transmission) at some pawn shop or other place where such things are found. This way, I buy a second cheap replacement trigger, a couple light springs, and I’ll have a reversible, variable speed vehicle. This idea currently exists only as an idea in my head, so we’ll see how it works out in practice. Fortunately, many have said I have a very imaginative mind, so maybe I haven’t botched everything before it’s even begun. J Regardless, that’s the plan anyway: what do you all think? (as to criticisms: please refrain from throwing overly heavy or sharp and point objects as I have a rather soft head.) Bing brings you maps, menus, and reviews organized in one place. Try it now. -- You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat -- You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat _________________________________________________________________ Bing brings you maps, menus, and reviews organized in one place. http://www.bing.com/search?q=restaurants&form=MFESRP&publ=WLHMTAG&crea=TEXT_MFESRP_Local_MapsMenu_Resturants_1x1 -- You are currently subscribed to the "R/C Tank Combat" group. To post a message, send email to rctankcombat@googlegroups.com To unsubscribe, send email to rctankcombat-unsubscr...@googlegroups.com Visit the group at http://groups.google.com/group/rctankcombat
