Edge finding, 2 D replication

[johnm]

Folks -

Okay, we've got a chance at a job that requires using a bunch of floorboards (3/8" MDO) as templates to cut new floorboards. The spec calls for everything to be within 1/16 of the existing panels. We have a digital probe, but haven't really had the call to use it - as least for something this big. The total # of parts we would need to replicate is about 100 per job, total of about 700 SF. The client does NOT have drawings, and we wouldn't know specific profile or edge complexity until we had the panels in hand. The individual panels are mostly angular, with a few holes in them, and range from just under full sheet size (~40 x 80) down to about 8" square.

I'd appreciate any input and some way of figuring out how to estimate "copy machine" time. I am already figuring I'd better be on the high side...

OTOH, have any of you ever had any dealings with using a FARO arm Coordinate Measuring Machine or their cost? It seems like overkill in this application, but was suggested as a possibility.

TIA,

John Moorhead

[Brady Watson]

John,
For this type of job, I would price it per piece. If I were doing it, I would charge between $25-50 each panel depending on size & complexity. Nobody else is going to beat that price.

In terms of time, keep in mind that while the 2D probing routines are good, you will still have some software work to do to cleanup the corners (which will be rounded & not square) & you will have to manually digitize the holes depending on how big they are, by moving the tool to the center of the hole & recording the X,Y position in a notebook. I find a vbit most helpful for finding the center of holes rather than using the probe as a locator. If you are doing 100 panels, I would allocate a full week to digitizing & a couple days to clean them up & insert the holes in CAD.

Another option, and this depends on your speed & efficiency in your CAD program, is to take a bird's eye view with a camera & pull the photo into CAD. Then trace out the outline & check dimensions against your template. If you accurately trace the outline, you can get really good results.

Faro arms typically go for about $8-20k used depending on model. I think that they are between $15-40k new, depending on what you get. A more affordable version is made by Immersion called a MicroScribe, and that runs between $4-18k depending on model. You can find them used sometimes on Ebay for around $1,000 to $2500. The MicroScribe takes some coordination to use.

-B

[bill.young]

Hey John,

I did some digitizing of paper plans a while back using a downward-facing webcam mounted on my ShopBot's Y car and the Record function in the Keypad. I converted it to a dxf file that could be brought into Part Wizard to create the toolpath, and it worked well for finding keypoints of angular shapes. You could use the same process with a v-bit as a pointer and just eyeball when you were over a corner, but it's pretty tough to get a good angle that way.

If you're feeling adventuresome drop me an email and I'll see what I can dig up on the process.

Bill