Scratch Built Roll Cage tips?

[heroncustom]

hey everyone wanted to try my hand at scratching a roll cage amd was hoping to find some tips and tricks for jigs or measuring or (fisheye?) notching but my searxhing is in vain can any one point me in the right direction or give some tips themselves? would be greatly appreciated!

[Ace-Garageguy]

It's called "fish-mouth", for obvious reasons......the resulting look after the end of a chassis or cage tube is cut to intersect another tube. I've found the best way to do it on scale models is to cut the chassis tube in question just a little long, and then use a round file of the same diameter as the tube your "fish-mouthed" tube will attach to, to create an accurate and tight-fitting fish-mouth.

Naturally, if both ends of the tube will have to be fish-mouthed, you'll have to allow length for that as well. Working slowly and carefully is important, and hand-fitting as you go is the only method I've personally found to work accurately on scale models. Just a few thousandths of an inch error can make a cage or frame cockeyed, wonky and warped, so neatness counts.

I usually lay straight tubes (styrene rod) in an X-acto miter box for stability, with one end sticking out enough to do the file work.

If the ends of a tube need to be fish-mouthed at different angles relative to each other, it works for me to do one end first, place the tube in the opening, mark the rough overall length, the primary angle of the second cut, and the centerline of the desired fish-mouth....then carefully sneak up on the final fit.

I built the upper and rear sections of this cage using the above techniques.

There are some guys on here who do entire tube-frames and cages, and do a lot of them very well. Hopefully they'll weigh in with more and better ideas than I've presented.

Edited December 3, 2013 by Ace-Garageguy

[John Pol]

What do you use as a file a round file or what?

John Pol

[Ace-Garageguy]

What do you use as a file a round file or what?

John Pol

Yes, a round file the same diameter as the tube you're intersecting.

Also try this link to a google search of threads on this forum about roll-cages. Just about everything you could want to know is already there. https://www.google.com/search?q=site%3Amodelcarsmag++roll+cage&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#q=site:modelcarsmag.com++roll+cage&rls=org.mozilla:en-US%3Aofficial

Edited December 3, 2013 by Ace-Garageguy

[ScaleDale]

Chassis and cages are 1 5/8 in 1:1 and that's around 1.6-2.0mm in 1:25. To properly notch the tube - use rod - at that scale would require a 2 mm round file and I've never seen one of those. I use a bit of a scorched earth approach for mine. I dip the ends of the rod in a strong liquid glue like Plastruct Plastic Weld and press the pieces together. It melts the plastic and you can smooth the parts together with the edge of an Xacto blade for a second or two. I do this on a glass surface. When I'm done I smooth the edges by adding a drop of Mr. Surfacer 1000 or 1500 liquid filler using the tip of a tooth pick and sand it a bit. After a coat or two of primer and finish coat, it looks pretty good. Here is my still in progress Pro Mod '49 Merc.

All the bends were done with a heat gun and wooden forms.

Dale