Need CAD Advice

[MK]

You're underrating welding distortion and that a hand cut sheet can be made pretty flat with very primitive tooling (it's called hammer).

In a nutshell: You will not get 100% flat surfaces in the finished product anyway. There's no sense starting with "perfectly" flat pieces.

How about doing a simple training piece like an oktaeder? Cut the pieces by hand, hammer them flat, then tack & weld.
My fist aluminum tank started as a training piece and as it was fuel tight on the first try, I used it on the race bike.

[Smoker]

Thanks.

I'm not very concerned about the aluminum pieces being flat. Very concerned about gaps where the edges come together. There will also be many more welds than on the usual-shaped tank construction.

The frustrating part is that my problem is so simple to fix, but I can't find the right button to click, even though I've done it before. I can easily CAD draw a triangle with two sides the correct length, but when I get all 3 sides the correct length, they don't join up.



I understand what you're saying about welding distortion. I'm not trying to CAD the whole tank before welding. Just some pieces to get me started.

[Yellow and Black RZ]

The 2 rectangles are even easier.

Both are 5.000" wide.

The first one has angled cuts on the short sides. Here is a side view with the known dimensions. Just need the dimensions of lines D, E, & F.


The second rectangle only has an angled cut on one short side. Here is a side view with the known dimensions. Just need the dimensions of lines G & H. The rectangle does extend 0.125" past the triangle piece.


Knowing the angles would be cool, but probably not necessary. Thanks much for any help. I'll keep trying on my own, as much as possible.

Distance between B G is .125 as well?

[Yellow and Black RZ]

Might not need this anymore. I appreciate the challenge.
Entirely possible i misunderstood something and made a mistake.

Have in 1:1 pdf if you want it.
I also have each part in .125 thick cad models if you wanted that. I can send to you in .stp format.

smoker-1.jpg (106.45 KiB) Viewed 1374 times

[Smoker]

Dude! Unexpected happiness is a truly great thing. I won't even try to explain how bad I need a hug.

Yep, all the pieces are 0.125" thick. Drawing looks cool. I'll try to calm down a bit and take a closer look.

Thank you so much.

[Yellow and Black RZ]

Dude! Unexpected happiness is a truly great thing. I won't even try to explain how bad I need a hug.

Yep, all the pieces are 0.125" thick. Drawing looks cool. I'll try to calm down a bit and take a closer look.

Thank you so much.

Glad to help out. Especially to spread some happiness around.
Let me know what you need changed or if there is anything else I can do.

I can round up the dimensions and include the angles if you'd like.
Hope it helps!

[Smoker]

YES!! Thanks again.

Let me show some grattitude by describing the situation.

In June of 2009, I posted about my ideas for a custom fuel tank. The OEM tank is plastic and is shaped to connect to high-mounted radiators. I found an aftermarket aluminum tank photo and did a minimal photoshop to get a more pleasing, angular shape. I won't be using the OEM radiators.

[Smoker]

In July of 2009, I tried to do a simple mockup to look at the shape. I didn't even have the seat or upper triple, yet.

[Smoker]

Well, a lot of stuff has happened since then. One of the worst things is that my friend and welder Roger retired.

The latest iteration of the tank takes styling cues from the tail. Has an angled top and the diamond shape.

[Smoker]

The pieces we're currently working on are the bottom of the tank that sits down into the frame.







That extra piece is the back plate. That should be easy to draw. Just 90 degree cuts, no angled cuts.

[Smoker]

Still working on the top pieces. Trying to keep things simple.

[Smoker]

I can round up the dimensions and include the angles if you'd like.
Hope it helps!

That would be awesome!

Welding lab starts up again August 29. Then, I can ask the instructor about getting the first pieces cut. With the proper CAD, like you've made, I should also be able to get the pieces cut on my own, if necessary.

The rectangle piece on the left of the drawing is the front. Two of the triangle pieces make up the sides. The rectangle on the bottom is the bottom piece.

This isn't a good pic, but you can see what I'm up to. Everything above the red line got the chop. When I get the first 4 pieces cut, I'll tack them together. Then, I can temporarily secure it in position.

Then, I can temporarily secure the back piece into position (yellow).

Then, I can measure and draw the connecter piece (blue). Should be an easy piece to draw. Just a strip about 1.250" wide.

There's also another small piece I haven't shown, yet. I call it the cap piece. It fits onto the cut-off corner of the triangle. So, about 0.250" x 5.00". I'll draw that today, now that you've given me the missing dimension.

[Smoker]

Have in 1:1 pdf if you want it.
I also have each part in .125 thick cad models if you wanted that. I can send to you in .stp format.

Thanks, much. When welding lab starts in 2 weeks, I'll find out what I need.

The 2 machine shops I previously used couldn't use .stp files, so it was fine to submit my hand drawings. If someone can use your .stp file, they wouldn't have to repeat your work. So, I'll find out ASAP.

[Smoker]

Here's my drawing for the back plate.

Probably should mark the center of the top and bottom. Or, try to measure the angles of the corners.

Thinking someone could use these dimensions, but come up with an asymmetrical piece.

[Yellow and Black RZ]

Have in 1:1 pdf if you want it.
I also have each part in .125 thick cad models if you wanted that. I can send to you in .stp format.

Thanks, much. When welding lab starts in 2 weeks, I'll find out what I need.

The 2 machine shops I previously used couldn't use .stp files, so it was fine to submit my hand drawings. If someone can use your .stp file, they wouldn't have to repeat your work. So, I'll find out ASAP.

I can more than likely export the file in a format that will work for you. let me know.