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RoosterBooster
05-13-2010, 11:10 PM
here is a simple trick for the DIY guys to make a sharp corner stronger, not so sharp, very easy to build and with very minimal tube fitting: (i hope you guys can follow my bad English :o)

i noticed that a lot of the DIY frames that are posted here on MBN have miter cuts. i personally think simple "but-welded" miter cuts create a weak spot and i try to avoid them.
... however, if you have to do one you can make them stronger with a "internal gusset" ;
cap-weld one of the miter cuts with a nice fitting oval steel plate plug and then but-weld them together
.... but the "trick" that i sometimes use is actually stronger and a lot simpler;

here is what i start with;
http://www.glamisdunes.com/invision/gallery_imgs/1272315848/gallery_3536_686_1814.jpg
a hollow 1.5" steel ball ....welded together out of two hemispheres (they are simple stamped mild steel ... but at ~.110" wall thickness they match fairly well with the strength of .095 DOM)

... the first tube is meeting the ball with a simple square cut...
http://www.glamisdunes.com/invision/gallery_imgs/1272315848/gallery_3536_686_33007.jpg
butting a .095 tube to the ball will give you a nice groove for welding (notice that i quickly buzzed this "scrap pile" sample together ... a actual frame weld could be a little thicker to fill the groove better;))

then you meet the second tube to the ball... again; its basically a square cut with only minimal notching where it meets the first tube ...
http://www.glamisdunes.com/invision/gallery_imgs/1272315848/gallery_3536_686_2146.jpg

and here is the final corner with the 3th tube added;
http://www.glamisdunes.com/invision/gallery_imgs/1272315848/gallery_3536_686_25141.jpg

the spheres act as internal gussets and make the corner very strong and crush-proof...
http://www.glamisdunes.com/invision/gallery_imgs/1272315848/gallery_3536_686_12058.jpg
... but with a nice and soft rounded outside corner;)

here is a link to one of the many places where you can buy spheres; King Architectural Metals wrought iron metal balusters finials casting steel ornamental forged gate fence stairs Access control (http://www.kingmetals.com/Default.aspx?page=category%20search%20results&CatList=20323&Parent=947&tree=936*Balls*0%40%40947*Hollow+Steel+Hemispheres *20323@@)
(i would recommend to buy spheres and weld them yourself with a good amount of penetration...usually the already welded (fence decoration) balls have very questionable welds [smilie=icon_razz2.: )
i hope somebody can use this :p

pooologist
05-13-2010, 11:32 PM
thanks man

Travitanium
05-14-2010, 02:46 AM
[smilie=bow.gif]Wow, excellent idea!

bazz
05-14-2010, 05:18 AM
Does'nt seem right does it?
Too simple...why did know one else think of this before? :eek:
Great solution,force distributor,(let the force be without you):D even from a Kiwi!:p
Well done Mate.;)

telodge
05-14-2010, 09:57 AM
thats a great idea thanks for sharing

dirtreaper
05-14-2010, 01:52 PM
Thats awesome great idea I have to try that...lol
[smilie=thumbs_up.g:

megadesertdisel
05-14-2010, 04:04 PM
sure it might be strong but sure does not look pretty. whats wrong with bending notching tubing?

RoosterBooster
05-14-2010, 06:12 PM
sure it might be strong but sure does not look pretty. whats wrong with bending notching tubing?
i think you miss-read my post (it could also be my bad english skilzz[smilie=icon_razz2.:); this sphere trick is not really intended as a replacement for bending and notching ;) ... i personally try to avoid a corner like that ... but sometimes there is just no other way [smilie=dunno.gif].... like this corner on "el diablo`s" frame :
http://farm4.static.flickr.com/3489/3759999477_a2dce37d59.jpg?v=0
(right in front of the C/O reservoir)

so the trick with the sphere is just a simple replacement for a "mitered" or "terminated and plugged" tube corner.

however, if you are a DIY guy on a tight budget (and buying a bender is not in that budget) you could , if you design the frame accordingly, also build a complete frame without bends... just straight tubes and sphere corners.
there is nothing wrong with using just straight tube (after all; a straight connection between point A and point B IS the strongest way to connect them :p)
IIRC yoshi`s frames are kinda like that; mostly straight tubes with minimal bending


IMHO bends are great for a more finished and "rounded" look (if you like that look) ...but when you bend a tube you are weakening the tube and it is loosing its uniform shape...the wall thickness on the outside of the bend gets significantly reduced. there is also the risk of hair line fractures if you bend brittle tubing (like heat treated CM) around a tight radius. this is the reason why i try to design my frames with only the bare minimum of bends and i also like to use a "wide" bending radius (7" CL radius) or rolled "soft radius" bend sections ;)

megadesertdisel
05-14-2010, 07:21 PM
makes sense but i would just use bends and notching, but thats just me.



on a side note are you going to the Cinders for Memorial day? i will be there on saturday.

bdkw1
05-15-2010, 02:48 PM
Mitered corners are fine if done correctly. Cut a flat piece out of material the same thickness as the wall of the tube. and cap one of the pieces of tube before you weld the 2 together. This will make a nice little bulk head and make the joint nice and strong. I also drill a breather hole in the bulkhead.........

yoshi
05-16-2010, 08:12 AM
IIRC yoshi`s frames are kinda like that; mostly straight tubes with minimal bending




I know it looks that way, but there's actually 31 bends in the chassis alone, more than a lot of rails...:D

yoshi
05-16-2010, 08:14 AM
... but sometimes there is just no other way
(right in front of the C/O reservoir)



You could make the tube go all the way to the floor and avoid the intersect in that particular spot, prob. speed up the build time a bit as well.......

kliff
05-17-2010, 05:38 AM
Thanks RB, on order, should be here this week, never hurts to have alternate resources in the parts bin.

RoosterBooster
05-17-2010, 11:35 PM
You could make the tube go all the way to the floor and avoid the intersect in that particular spot, prob. speed up the build time a bit as well.......
yes, your right..... i guess i used a bad example:p
i found this pic in the build thread of "Deranged"...
http://www.minibuggy.net/forum/attachments/projects-progress/16936d1257992335-west-michigan-r-16-shotgun-111109-005.jpg
... this is a corner where the sphere could be used to make the connection stronger and to avoid the sharp corner from sticking out ;) ....
i guess i repeat it again ; the sphere trick is NOT the best way to do a corner and there are maybe BETTER ways to do it (or to completely avoid a corner like that) for the guys with all the trick tools and benders....
this is simply ONE of the ways to do a corner that could be a easy alternative (due to its mainly straight cuts) for novice builders with limited tools and/ or experience [smilie=alright.gif]

Deranged
05-19-2010, 01:36 PM
glad I can be an example of what not to do[smilie=strokin.gif]

RoosterBooster
05-19-2010, 03:51 PM
glad I can be an example of what not to do[smilie=strokin.gif]
LOL ..... i`m sorry [smilie=alright.gif]

...nothing wrong with your corner.... its just that the sphere would be a little less complicated [smilie=icon_razz2.:

Deranged
05-25-2010, 08:54 PM
So instead of a miter joint, you can call it a ball joint...[smilie=rofl.gif][smilie=rofl.gif]:pyou better put a patent on that..LOL

Justin.

RoosterBooster
05-25-2010, 09:33 PM
So instead of a miter joint, you can call it a ball joint...[smilie=rofl.gif][smilie=rofl.gif]:pyou better put a patent on that..LOL

Justin.
LOL
imagine how cool it would be if you could say that your buggy has steel balls :eek: :p

Odyknuck
05-27-2010, 02:55 PM
I like it. Nice fix in a pinch!