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3ps
05-10-2009, 10:03 AM
Hi, I have a buddy 32 and I am doing a job for a city park doing buisness names on 6' park benches made of trex type material. I figure I am limited to 2'of lettering per slat as I do not really want to index. What would be the best way to do this, V carve, just flat pocket, or flat bottom pocket with ball nose bit? What would be a good font for this job? Do you think the plastic type spray paint would be ok for fill? I am also looking for a hold down method? Man thats a lot to ask!! I just have not done a job this big and do not want to mess up any benches if the material moves. Thanks and Sorry for the amount of questions, Doug

mikek
05-10-2009, 10:50 AM
Doug, I think I would V-Carve it if the letters are small. The results will be very smooth in this material.* I have machined small test fixtures out of it with very good results.* There might be some fuzz around the edges when done, but very light sanding with 220 grit removes it.* Practise on some cutoffs first and see what looks good to you.* Don't know what kind of paint would stick to that stuff. It is recycled plastic.* Remember when V-Carving that the larger the letter, the deeper it will cut.* Trex is not very strong to begin with and needs support every 12 inches when used as decking. You may want to use a simple "cut profile " toolpath with an endill or ball endmill for this reason and limit the depth.

dakers
05-10-2009, 12:26 PM
No paint really sticks to High Density Polyethylene. you can do a resin pour but i would not color the letters at all. these benches can last 50 years and you can read them fine without a resin pour to color the letters. the resin pour will have to be maintained over the years. You can search resin pour on this forum. for resin pour you would use flat bottom bit.

cnc_works
05-10-2009, 12:51 PM
The other issue you might encounter using V-carve is that the Trex is often not flat. So depending on the font you use, you can get variations in cutting depth that will affect the appearance of the font from character to character. The smaller the font, the worse it is. I did some large park signs with Trex and could see the variation even with them so I chose a flat bottom cut with a 1/8" Onsrud 0-flute.

And while I certainly don't have the experience to disagree with Dick, the guy that subbed the job to me painted the letters white and now, three years later, they still look OK. Don't know what he used though and don't know what they might look like in 5 years.

Lotsa luck!

Donn

greatzak
07-06-2009, 03:09 PM
Doug, i was wondering what design you used for those benches? Are they made just out of trex, im trying to do my eagle project but im having trouble finding a bench design to build out of trex for my project.