Sketch mode: draw your part to scale and we compile it

A photo tells GrandpaCAD what your part looks like. It doesn't tell us how big it is. So we rebuilt the sketch pad in the chat into a proper drawing board where every line has a real size in millimeters. You draw the outline, your drawing carries the actual measurements, and the AI builds to those instead of guessing from a photo.

The old pad was just a rough scribble: fine for a hint, useless for "this slot is exactly 12 mm wide." The new one is a real drawing tool. Every line, circle, and rectangle knows its size, and when you attach the sketch it goes into the chat as a clean image with the measurements labeled right on it.

Opening it

In the chat composer, hit the plus menu and pick "Draw a sketch" (there's also an "Or draw a sketch" hint under the image box). It opens full screen, so you get the whole canvas.

The tools

Pick a tool from the toolbar and a color, then draw:

• Freehand pen (the default) for quick strokes
• Line, rectangle, circle
• Slot, the obround shape you want for a bolt channel
• Polygon with 3 to 12 sides (hexes come dimensioned across the flats, which is what you actually measure)
• Text, for labels or engraved names
• Dimension, to call out a distance between two points

Here's the part I like most: scribble a rough circle or box with the pen and it snaps into the precise shape with rounded millimeter dimensions. Draw a wobbly rectangle, get a clean one. Strokes that don't clearly match anything stay freehand, so you don't lose a genuine curve.

Getting the sizes right

Every shape shows a live measurement while you draw. Tap the label and type the exact number, so "roughly this wide" becomes 24 mm in one tap. As you move things around, endpoints, midpoints, centers, angles, and the grid all snap with little indicators so edges line up on their own.

Select something and you can duplicate it, mirror a copy across the right or bottom edge (handy for symmetric parts, draw half and flip it), round the corners of a rectangle, or nudge with the arrow keys: 1 mm a tap, hold shift for 10 mm, hold alt for 0.1 mm. Undo and redo are unlimited. Pinch or scroll to pan and zoom.

Tracing a photo

If you started from a photo or an existing model image, it drops in as a faint tracing layer. Draw over it to pull real dimensions off a rough reference, then toggle it on or off with the image button. Works with a finger, a mouse, or an iPad pencil.

When you're done, hit Attach. The sketch lands in the chat as a reference image, and you finish the job in words: wall thickness, hole positions, which face is the front. Then generate.