Engineering Drawings of Frame

[jossdude]

I have started to draw an engineering drawing of the frame, after someone requested one on the Kickstarter comments.

This is where I am up to so far, not going to be able to work on it for the next few days, but if anyone sees any mistakes let me know



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Here are the updated Engineering Drawings for both v1.0 and v1.2. Hope they help people.

V1.0

Click to Enlarge to Full A3 sized Image



V1.2

Click to Enlarge to Full A3 sized Image

[Eventorbot]

Very nice work. I needed this also.

[jossdude]

Here is an updated version of the drawing (Click on it for a larger view)



I am still playing around with spacing of the dimensions to make it clearer but you should get a much better idea of it now.

Duy, i have ever so slightly altered some of the dimensions. So of the holes were place 43.7mm and have changed them to 44mm and have changed the rectangular openings from 25.4mm (an inch) to 25mm. Are any of these going to be an issue or is that ok. My worry was that it was making it look like those particular dimensions needed to especially accurate.

Any anyone see anything obvious that I have missed?

[Hennes Media]

Thanks this looks great

[davidfi]

Why not use the sketchup model?
What can you do with this drawing that is not easier in sketchup?

[jimdaug]

Since I'm at the end of a CAD degree program I'll offer a few suggestions because they are things we would get points taken off on an assignment.

Keeping in mind you aren't finished
-The dimensions on the left shouldn't be outside the the title block.
-There will need to be a section facing the bottom of the top arm to dimension the slot and holes.
-On the left view I'd dimension the 8mm between the holes instead of single dimensions to each one. I.E. 48mm to the top hole and 8mm to the next instead of 66mm. Similar to how you have the right view. Same on the back view.

Also, from a fabrication standpoint, and this goes for anything where you're cutting rectangles into parts, be sure to radius the corners so that a stress crack doesn't form from the 90 degree corner. I'm working on lowering an old truck and in everything I've read about it any time you make cuts in a car frame you have to radius the corners. In this small of an application the forces might not be enough to actually cause a stress fracture, but it's good practice anyway.

Hope that helps,

James

[Z3phyr]

Jossdude - good job on the drawing. In my distant past I was draftsman, so I do have some recommendations.

First, on the hole locations, in the left view the dimensiond are from a datum (mfg edge) but in the other views the holes are dimensioned relative to each other. If your mounting external hardware to a specific hole pattern, then one should dimension the holes relative to each other to minimize tolerance stackup. Also should specify the holes are on the centerline or provide a dimension from a datum.

Recommend you use the same horizontal datum and vertical datum for the dimensions for maximum accuracy (i.e, use the same vertical edge like the outer left edge of the "C" shape instead of some dimensions from the outer right edge of the "C"). This is a good rule of thumb, but you may violate it if the design intent requires that a hole or opening be spaced from another edge.

Machine shop will need to the know the standard tolerance for your dimensions (typically +/- .030" for machined parts) and if there are any critical dimensions requiring tighter tolerances than standard (just call them out on the drawing or with a note).

Recommend you run this by the fabrication shop that will build this, and they will give you the best input.

Again - good job! Regards,
Z

[jossdude]

Keeping in mind you aren't finished
-The dimensions on the left shouldn't be outside the the title block.
-There will need to be a section facing the bottom of the top arm to dimension the slot and holes.
-On the left view I'd dimension the 8mm between the holes instead of single dimensions to each one. I.E. 48mm to the top hole and 8mm to the next instead of 66mm. Similar to how you have the right view. Same on the back view.

Also, from a fabrication standpoint, and this goes for anything where you're cutting rectangles into parts, be sure to radius the corners so that a stress crack doesn't form from the 90 degree corner.

- On the second updated version have sorted out a few of the things you mentioned. Is hard to tell the order that things have be commented on though due to the delay in Duy accepting the posts (maybe something to consider Duy, or to get a few moderators that can help with the Forums?)

- Shall add an additional view to the underside of the top section to show the holes and rectangle

- Will also alter the dimensions to suit the pairs of hole as well.

If your mounting external hardware to a specific hole pattern, then one should dimension the holes relative to each other to minimize tolerance stackup.

Recommend you use the same horizontal datum and vertical datum for the dimensions

Machine shop will need to the know the standard tolerance for your dimensions (typically +/- .030" for machined parts) Recommend you run this by the fabrication shop that will build this, and they will give you the best input.

Z

- As mentioned earlier shall alter the dimensions to suit that. Had forgotten about tolerance stack-up. Been a while since I have done a drawing that others are going to be working from without me being there.

- On the second version that I posted earlier started to alter the dimensions so all are from the same datum where suitable just not go round to doing all of them. Will be able to work on it again this evening once back from work.

- Shall email Duy to ask about tolerances etc from his experience of the design and previously fabrication as I am only working from the SketchUp model. Was going to put on a note about tolerances and also that fact that can use 2.5" square stock.

Why not use the sketchup model? What can you do with this drawing that is not easier in sketchup?

- You need a computer to view the SketchUp model and a bloody good memory to remember all of the dimension when making the component. This will also all of the dimensions to be seen on one piece of paper that can be taken to a fabrictors (possibly with the CAD model) or to your workshop.

That for the input everyone, will do a bit more work on it this evening and try to post up an updated version once have altered said points.

[Eventorbot]

Here are some files from my metal fabricator company.
http://eventorbot.com/files/new_frame/E ... 20v2-1.pdf
http://eventorbot.com/files/new_frame/E ... sembly.pdf

[jossdude]

Updated version of drawing, again click to enlarge



Think have altered everything that was mentioned earlier. Any more suggestions/advice/errors?

Looks good Duy, is going to be much more professional looking and easier to assemble and fix. Getting ever more excited.