I am looking at making a 3d topographic map on the Lasers and I am wondering if anyone had some advice or experience
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Someone here did an awesome one a bit back. I’m going blank on who it was but I’m guessing someone will know
This?
Yes, thx for finding that
Here’s one I made a couple years back of one of my favorite riding areas. I used a link I found on Hackaday as a tutorial. I’ll try to find the details tomorrrow.
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Oh my gosh. I LOOOOVE this idea!
My husband has really gotten into hiking, usually 6-12 miles, on weekends when the weather cooperates. He has some favorite local(ish) spots. I just found a topographical map for it. I knew it had to have a lot of varied terrain given his comments and what the biker sites say on it.
Isle du Bois at Lake Ray Roberts, for anyone curious. Not a long drive from this area. He usually gets there at sunrise and that time of day, there are tons of deer out. Gorgeous pictures he’s taken.
I think it would be an amazing surprise gift. This might have given me the push to finally learn lasers this summer.
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Here’s the article on HackADay.com I used as guidance for making my map.
The basic software used is QGIS. The source of the terrain elevation data is the US Government DTED (digital terrain elevation data) files - not topographic maps. QGIS takes the DTED data and computes the elevation lines from that data. This data is reported to the nearest meter in an array for every 1/3/30 seconds of latitude and longitude, depending on the quality of the dataset (Level 2/1/0 respectively). The DTED Level 2 data equates to roughly 30 meter/100 foot resolution but is only sparsely available. You should be able to get DTED Level 1 (100 meter resolution data) from USGS web sites. This roughly equates to 1:250,000 scale topo maps.
There is also GIS (Geographic Information System) available which will show trees, roads, buildings, et al. QGIS supports this as well, IIRC.
I ride horses at Isle du Bois sometimes: the terrain there is pretty flat compared to the area in the Rockies I used: on my map each layer of plywood represents 200 feet of elevation change. You may find that the relatively flat terrain around Ray Roberts may not show as interesting a result.
You may have to tweak the layer interval and the starting altitude offset (lake “Full Pool” level would be good) to get a good representation of the terrain. Note that lower layer intervals does not change the coarseness in the underlying data’s resolution: 100 meters is not super-detailed when trying to capture a creek drainage that is only 5 meters wide.
FWIW, “Full Pool” water level for Lake Ray Roberts is 632.5 feet:
http://rayroberts.uslakes.info/Level/
Prepping to Cut
I converted the QGIS results to an SVG, then in Inkscape I went through and color-coded each layer to correspond to the sheet of ply from which it would be cut. I put together a spreadsheet mapping color to layer to help keep things straight in the next step.
I had 11 layers of terrain, but I only used 8 pieces of plywood by cutting layers 1 and 9, 2 and 10, and 3 and 11 out of the same piece of ply. I cut the lowest layer out with an extra 1/4 inch border all the way around so I could attach the frame via a 1/4 inch rabbet cut into the frame pieces.
For each layer, I ETCHED the layer above, then CUT out the current layer. That way I had alignment lines on each layer to aid in the placement of pieces for the layer above. Using the spreadsheet helped because I had to iteratively turn layers on and off and change the settings for each sheet of plywood. Watch to make sure tiny layers don’t drop through the grid on the laser. You may have to reprint selected tiny bits if they break or are lost ( I never could find two pieces and had to reprint them).
Once cut out, I glued layers together in pairs, let them sit for an hour, then glued the pairs together. Lather, rinse, repeat until the job was done.
FINISHING
The frame was red oak, which I “ebonized” using vinegaroon (aka iron acetate) made by soaking rusty iron in vinegar. It is called vinegaroon for leatherworking (and turns vegtan leather black in about 2 seconds - cool to watch). The iron acetate reacts with tannins to darken the material.
The plywood was left natural, but sprayed with polyurethane finish.
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