Toolmaker72 485 Posted May 13, 2022 Just sharing a build that I’m doing. I believe the chassis started out as a king Blackfoot. A second hand purchase with front suspension missing. I bought it for the double wishbone rear suspension gearbox that fits onto the orv chassis and then complete as a red monster beetle with a brushless motor. Well I thought the wheel base looked better for a scorcher/ blitzer beetle hybrid build. Parts are a mix and match to get things sitting right and working. I had the random red front suspension tower to modify with shorter front shocks that fit nicely under the scorcher bonnet/hood. The lower mounting point for the front dampers uses longer wishbone bolts I made from a m5 Allen bolt. The lower bolts had worn through the plastic steering upright so that was repaired using a brass tube bush. The original holes made larger to accept the tube and allow original lower wishbone bolts to be used. The yellow cva dampers were made softer with 2 extra holes drilled through the piston/plunger (1.5mm). Rear red dampers were limited inside and outside to shorten the stroke and give a level chassis but also stop the gearbox bottoming out on the floor. Now I know the length required I think I’ll replace with yellow cva units to match the front. Usual ballraced gearbox ready for the 2845 4370kv motor. I’ve kept the small monster beetle brass drive pinion. The extra revs the motor gives will more than compensate for the low gearing. I’m hoping the wider track makes the chassis more stable for faster cornering speeds. First run will be a regular 7.2v pack then if ok will try a 3s battery. To mount the body, I’ve used the position on the orv chassis that the frog uses but with extended brass mounts. The hole in the body is approx 5mm to the rear of the marked area used for a monster beetle fitment. The front mount uses the original hole meant for a sand scorcher which is already there. Roof body mount holes have been filled. I’ve only just screwed and glued the body details on today so will let everything set glue wise before blending in ready for primer paint. Wheels are white so I’m thinking a white body with either a scorcher inspired blue side panel or white with a yellow side panel to tie in the yellow cva dampers. pictures below of the build so far 4 Share this post Link to post Share on other sites
bRIBEGuy 2916 Posted May 13, 2022 Wacky. I like it. Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 13, 2022 Forgot to say the bump steer is horrendous using the standard steering parts. I had already made a new Bush to help remove the massive play in the mechanism. I might just centre mount the steering servo and steer directly off that as the monster beetle. Any better ideas are more than welcome 😊 Share this post Link to post Share on other sites
Frog Jumper 3605 Posted May 13, 2022 https://www.tamiyaclub.com/forum/index.php?/topic/91616-blackfoot-12mm-front-hex-mod-project/&do=findComment&comment=771886 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 13, 2022 18 minutes ago, Frog Jumper said: https://www.tamiyaclub.com/forum/index.php?/topic/91616-blackfoot-12mm-front-hex-mod-project/&do=findComment&comment=771886 Thank you 👍. I have those Parma steering arms on a regular monster beetle and they do work well in reducing bump steer. These later steering arms are so wrong. I think first thing is remove the ball joint and raise it level with the joint on the chassis and go from there. 🤔. 1 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 14, 2022 A couple of close up pictures of the stepped bolts I made to hold the damper in place. Also I borrowed monster beetle uprights and steering knuckles from my bitsa mule to see if the they fit ok with the king Blackfoot wishbones. Answer is yes. Bump steer virtually gone as well. I need to shorten the steering arms properly to adjust but I think it’s ok. The monster beetle parts do give a little camber with the suspension compressed though so i suspect possible shorter upper wishbones are needed. Im thinking of just centre mounting the steering servo as well so all that steering play can be lost. No need for two servos anymore when using an esc. 1 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 15, 2022 Nope too much camber. The wider wheels just make it worse. Trying to keep things simple so reverted back to the king Blackfoot parts. The steering arms will have the ball joint raised. I measured 20mm which is quite a bit but will see how it works once I make the little extension pieces. Share this post Link to post Share on other sites
Frog Jumper 3605 Posted May 15, 2022 The KBF uses the SBF hubs, and the SBF uses the BF sus arms, ie the BF hub should work with the KBF arms and therefore you can use the Parma bump steer knuckles??? Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 16, 2022 11 hours ago, Frog Jumper said: The KBF uses the SBF hubs, and the SBF uses the BF sus arms, ie the BF hub should work with the KBF arms and therefore you can use the Parma bump steer knuckles??? The parts fit but the securing pivots holes are in slightly different positions which is giving me camber the wrong way unless I make shorter top wishbones to counteract the excessive camber. Even the standard set up induces camber when the suspension is compressed but at a smaller amount. Standard Blackfoot front suspension stays nice and flat by comparison. They clearly have a shorter top wishbone. I’ll raise the ball joints on the steering knuckles and go from there. It will probably be a bit weak that high and no doubt mean a pair of new steering knuckles 1 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 16, 2022 I managed to make a couple of extensions to the steering knuckles. Removing the original ball joint is a drill out job as the part has a hidden collar and is moulded around it hence it can’t be unscrewed or simply tapped out. Pictures below show the extensions fitted. As suspected they flex. So I need to make from a bit of aluminium incorporating a web and a slight crank away from the tyre. 1 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 16, 2022 Although the extended parts flex due to being bolted to nylon they do get rid of the bump steer. pictures below show wheel position with extended and compressed suspension with servo in same position. Very pleased with that result. Now to measure up and machine a tidy pair of steering knuckles 1 Share this post Link to post Share on other sites
Frog Jumper 3605 Posted May 16, 2022 38 minutes ago, Toolmaker72 said: I managed to make a couple of extensions to the steering knuckles. Removing the original ball joint is a drill out job as the part has a hidden collar and is moulded around it hence it can’t be unscrewed or simply tapped out. Pictures below show the extensions fitted. As suspected they flex. So I need to make from a bit of aluminium incorporating a web and a slight crank away from the tyre. How tall are these extensions??? Great work BTW! Thanks, Terry Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 16, 2022 25 minutes ago, Frog Jumper said: How tall are these extensions??? Great work BTW! Thanks, Terry 20mm 1 Share this post Link to post Share on other sites
J@mes 2326 Posted May 19, 2022 Nice fix for the KBF bump steer. I did the same on my BF where the knuckles are easier as the connectors are screwed in. Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 21, 2022 I’m thinking now to use regular monster beetle steering knuckles because it’s only a 5mm extension needed and being a longer unit the it’s less stress on the pivot pin as the unit is pushed and pulled via the steering arm. Also means I just need to make a pair of small brackets rather than spend a few hours machining. The uprights will need to be cut so as the taller steering knuckles will fit which is the downside but they are a naff design anyway. Hopefully will make these bits Monday when back at work 😊 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 24, 2022 Monday was busy with an actual work repair 🙄😊. This morning had a couple of hours to get as far as the pictures below. Little brackets made from black nylon to blend in to the original plastic. I need to secure these brackets with a couple of self tappers then finish mill the correct gap for the steering knuckle and drill a hole for the pivot pin. Possibly shape the bracket to look similar to the original part. Bit fiddly but getting there 😊 Share this post Link to post Share on other sites
Toolmaker72 485 Posted May 25, 2022 Secured the new brackets and finished the size for the steering knuckle to fit between. Very pleased with the result. Hopefully find time over the weekend and fit these to the chassis and see how it looks. 2 Share this post Link to post Share on other sites
Toolmaker72 485 Posted June 3, 2022 The mods to the front suspension and steering works lovely. I’ve been chipping away with painting the body. Nothing fancy but I think it looks effective. Pictures of body so far. Still need to complete the driver figure and a few body details but overall I’m happy with it. 1 Share this post Link to post Share on other sites