Finally Tried Routing Some Corian with Engraver - Excellent Results

[Ross Moshinsky]

Today I had a bad day where I customer brought back an IkonMetal plaque that I spent way way way too much time on. Between all the time it took to engrave, to color filling, to the laser sandblasting mask that Ikonic swore would work and did not work at all; the whole job sucked. To cap it off, it wouldn't take to clear coat and began to peal off immediately once it hit the sun. The board also warped during the 30 minute install and a corner broke on the installer. In the end, I decided never again. Simply not worth the effort. If the customer wants that look in the future, it's bronze or bronze. I'll take some of the blame, but the product is far too finicky and fragile to ever be considered worth while. I'd strongly suggest that anyone stay away from IkonMetal.

So, now that that is out of my system; we were talking to the same customer and I was throwing out different materials they could use. Once again, they shot down using granite and Corian(my second suggestions behind bronze). Honestly, I typically push bronze and that is what the customer ended up ordering. I don't push Corian very often simply because I'm not very experienced with it and the did one plaque in Corian I previously did was a bit of a pain. After doing some research I realized I didn't follow the instructions on a few things, but none-the-less it left a sour taste in my mouth. (Hours cleaning up color fill makes me angry. Same reason I will never touch IkonMetal again).

I decided to try it messing around with Corian again because everyone on here says it's a great product. I got a sample piece a few days ago and decided to throw it on my IS 6000(fairly large rotary engraver) and began to cut out a heart shape with a .125" endmill. In the end, my results were fantastic. It will take probably 5 passes to get through .5" material, but I can keep everything in house and cut any shape I want. Well worth the extra minutes on the machine. I'm really happy with the result. I'll do all the edging with a hand held router and any bits I want. Granted, it's not as streamline as a router table, but frankly, my IS 6000 is my least used engraver and I'd rather it do something than nothing. I wouldn't trust a router table to do some of the work I do on the IS6000 and at this point, I'm not ready for another $6000+ investment on a router table.

Quite frankly, I'm excited to see how I can integrate this product into my sales. For a few hundred bucks between a new router, bits, and orbital sander, I think I should be able to see a nice return over the next few months.

I do have a few quick questions for the Corian guru's on here.

1) Do you clear coat the piece after you are done to protect the paint fill?

2) Is there any issue with heat? I was talking with a supplier and said Corian can be heated and bent or heated and sublimated. I do not want to offer this as an outside product and then have issues with heat. I doubt I would, but after this last project, I can't be too safe.

3) Are there any efficiency tricks with lasering this? I only have a 30W laser and frankly, I always find on stuff like this it takes forever to do a simple design, especially if I add a decent border.

4) On larger pieces I'll need to engrave it on the IS 6000 as well. I ASSume that a regular plastic engraving bit is the correct bit, but would a small end mill be a wiser and more efficient choice?

[Scott Shepherd]

No clear coat needed, no problem being outside it takes a lot of heat to get it soft (over 300 degrees), it lasers slow unless you have plenty of power, you can cut it with anything you want on the IS, it cuts like butter with anything that has a cutting edge.

[David Harvey]

Corian is great and very easy to work with. I route it using standard colbalt router bits...nothing special as all that I have used so far work equally well. I don't know about formig Corian as I haven't had any jobs that would require that, but I have heard that it can be bent after heating. I'm sure there are other folks here that have experience in this area with Corian and maybe they will chime in.
Usually, I do add a clear coat to the finish product. I use a gloss spray called 'ClearJet' that does an excellent job. It's easy to apply, dries fast and does a good job of blocking UV. Its available in both gloss and matte.
Corian can be tough to laser and you definitely aren't going to cut through it successfully (at least not in a productive sense). With a 75W laser, I use a setting of 85 speed, 50% power @ 600 DPI to engrave it. This will give me a ~1/32" or so deep recess for the next step of color fill. We use standard Acrylic paint, brush it on and allow to dry. After the drying, I use an orbital sander and sand off the surface, leaving a nice crisp engraving behind. Corian sands very well and it takes no time at all to produce professional looking results.
After the sanding, I spray it with the ClearJet to seal and protect it from the weather and handling.
The pic here is a gun grip I recently created a model of and machined on the CNC router. After routing, I did a quick sanding to get a smooth surface, then laser engraved the logo, paint filled it, then sanded it again with the orbital. A final spraying with the clearjet finished it off giving it a high gloss and crisp look....the customer was very impressed.

Hope this helps you some. As you work more with the material you will come to love it and you'll find yourself looking for ways to use it.

[Larry Bratton]

"..the customer was very impressed." Rightfully so, beautiful job David

[Chuck Stone]

you can also get a high gloss on Corian using micro mesh with no finish.

.. I'm just sayin..

[Keith Outten]

I can't say that I have ever sprayed a finish on Corian but I have polished a truck load of projects.

For exterior use if you want 50 years of zero maintenance use Dupont adhesive as your color fill. No UV protection is required either, wash with soap and water if it gets dirty.

Just for comparison's sake it takes me 25 minutes to laser engrave (0.032" deep) the average 6" by 8" Corian ADA door sign with my Epilog 35 watt laser engraver. The same job takes about 12 minutes with a Xenetech 60 watt machine.

I own a 24" by 30" heat press and I cook Corian for 20 minutes at 320 degrees F to get is soft for bending projects. I use the same time and temp for dye-sublimating color pictures onto Corian.

David, beautiful job on the gun grips!!!
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[Belinda Barfield]

Welcome to the world of Corian, Ross!

I've never applied a clear coat. Yes, you can obtain a high gloss with micro mesh but it doesn't hold up to wear and tear. I always go with a matte finish. As Keith said, for the ultimate in durability color fill with Coran adhesive. Using the adhesive, in my very humble opinion, also gives a more professional look as the surface of the project is completely smooth. Having said that, I typically work with only one or two colors for fill, nothing fancy around here.

[David Harvey]

....Thanks!

The use of the Corian adhesive is a great idea and one that I haven't tried yet. I bet that would work well.

On my next corian purchase I'm getting some of the adhesive.

Great idea Keith! Thanks again.

[Mike Chance in Iowa]

Ross,

Care to share a photo of your project with us? I don't recall anyone showing a corian project they made on a rotary. It's always interesting to see what people accomplish with different machines.

[Ross Moshinsky]

Thanks for all the great advice. The adhesive is a great idea. If you are a bit sloppy with it, is there any issue sanding it down?

For the clear coat, I wasn't really thinking of clear coating the Corian per say, but doing color, clear, and sanding. Really just to protect the painted areas.

I didn't think the heat would be an issue, but I needed to confirm after the last project.

As for finishing, I was planning on going with a "standard" semi-gloss. I figured semi-gloss is always the safe bet when it comes to durability, finger prints, and overall appearance. From what I've read simply going up the chain with sand paper and wet sanding at the higher grits is the way to go. Maybe on the last step, using some automotive polishing compound if you want to take it one further step.

I'm going to have to experiment with ways to be efficient as far as the engraving goes. A 6x8 piece of brass or plastic probably takes 10 minutes to laser with a logo, border, and reasonable amount of text. Using Keith's average of 25 minutes I'll have to carefully choose designs/borders to eliminate the amount of time it takes to engrave. I'm sure going with a simple offset border is most efficient as I can just run it on the rotary and it will take no time at all vs the laser which will take hours.

[Ross Moshinsky]

Update:

I went into the shop today to do a little more Corian work since its too hot to work outside and I just got some nice sized Corian pieces from a local shop for FREEEEEEEEEEEEEE.

Overall, things went fairly well. I did everything on the router today to get those settings squared away. Pretty much figured out all the settings as far as speed, rpm, feed rate, ect. It took a while, but I'm pretty sure I can get these produced in a reasonable amount of time.

I did have an issue. My end mill will only cut about 3/8". Does anyone have a source for 11/64" shank end mills that will cut at least 1/2"? Man I wish I won that Stinger this weekend. I'd be able to cut this stuff out in a pass or two instead of 6.....

[Mike Null]

So---did you take any pictures? What feed rate and rpm did you use?

[Ross Moshinsky]

I can't find my camera cable so I didn't bother taking pics as I went. I'll take some pictures once it is paint filled. Sorry.....

As for my machining process/review/ramblings:

Giving you actual feed rate/RPM is kind of tricky because I use Gravostyle and it is really a poor routing software. To change RPM and feedrate accurately, you need to do it in a long about manner which is a pain when tweaking things. I also think the end mill bit is not that great. I contacted 2 companies last night (2linc & bitsbits) to get a better bit for the job, or at least one that will cut down .5"

In Gravostyle, there is a default feed rate of low, medium, & high. High is .31in/sec I believe. medium is .18in/sec. Low is .09 in/sec. As for RPM, I really don't remember. I can adjust the rpm on the controller for the engraver and I was 17/20. I think the max RPM is 10,000, but I'm not 100% sure that is accurate.

For cutting the shape with the end mill, I found I could do passes of .07-8in at medium speed at 17/20 rpm and got favorable results. Any deeper and the engraver was getting over loaded. I dropped it down to low for a pass and it did not work at all either. It wasn't really cutting and the bit was being deflected slightly.

Obviously if you do some math .07-.08in for .5" Corian works out to about 7-8 passes to get through. I'm hoping to maybe get a better cutter to bring it down to 6 passes, but I think it's really the HP of the router and the strength of the gantry that is the issue. I'm trying to play it safe and not burn out my engraver cutting the Corian. I'm sure something like the Stinger could cut this out in 1-2 passes and it would take 5 minutes vs the 15 minutes it will take me. The fact the router bit is also very narrow (.125") also plays a roll because I'm sure most people will use a much more substantial bit.

For for the actual engraving. I ended up using standard plastic cutters. I found I could do high speed with 17/20 rpm. I did 2 passes to get an overall depth of 1/32" as Keith suggested. 2 Passes was a little time consuming so I'm going to try to get it down to 1 pass. I'm going to try to play with the feed rate again and maybe lower the feed rate a bit and maybe engrave a little shallower.

Opinions: If someone planned to do production runs of Corian regularly, I would suggest sticking with 1/4" material if possible. Taking 7-8 passes to cut out the material is too time consuming. Even ignoring time, I'm a bit worried about burning out the engraver cutting this regularly. 1/4" material you could do 4 passes at 0.0625 and it would be a lot easier on the engraver. If you want to cut 1/2" a lot, I'd buy a router table.

As far as engraving goes comparing it to a laser, there are some obvious benefits of both. Any simple vector boarder, the rotary is infinitely better. To get .1" vector boarder on a 30-35W laser, I'd expect it to take 45-60 minutes. Rotary will take 5 minutes.

Text is a different story. If you are on a 30-35W laser like me, I'd say big letters will typically be faster on the rotary. When you get down to doing plaques with letters in the .2" range, I'd say laser could be as efficient. I typically don't use less than a 3 line letter with the rotary unless it is a request. 3 line Roman or something similar will take a good bit of time to engrave regardless of cutter. I could do a 1 or 2 line letter with a fatter cutter but I find the results are not as elegant. Since the laser doesn't care about such things, it might be equal or slightly faster than the rotary. A 50-60W laser would probably the best choice for doing smaller letters.

The laser is obviously the best choice for any logo. Between changing tools 2-3 times on certain logos to all the passes, the laser will be faster under almost any circumstance. Obviously things like photos and gray scale images will always better on the laser as you can't achieve those results with a rotary.

[Mike Null]

Ross

I broke an end mill (expensive) trying to go too deep too fast on Trex. Be very careful and sneak up on the rpm. speed and depth. Better an extra pass or two than buying new cutters.

[Ross Moshinsky]

Yeah, I'm just always trying to optimize settings. I'm a bit of an efficiency nut when it comes to engraving/cutting/machining. I always want to find the fasts rate to run the machine to give me the best results. Sadly 7-8 passes is the best I can do comfortably, so it is what it is.

Mike: On a side note, where does Sawmill stand on small group buys? I'm getting some feedback on cutters from a few places and most are saying "custom" ie quantity. I doubt there would be much interest on here, but they aren't talking large quantity (10 pcs) but it's more than I want to buy. Is there a way I can gauge some interest to see if we could get some people for a group buy or is that against the rules?

[Belinda Barfield]

Mike: On a side note, where does Sawmill stand on small group buys? I'm getting some feedback on cutters from a few places and most are saying "custom" ie quantity. I doubt there would be much interest on here, but they aren't talking large quantity (10 pcs) but it's more than I want to buy. Is there a way I can gauge some interest to see if we could get some people for a group buy or is that against the rules?

Ross, there have been some organized group buys. You might try looking in the Community Section and checking to see if there is a social group for your area. One purpose of the social group is to organize and negotiate group buys.

[Dan Hintz]

I believe group buys are considered acceptable as long as the intent is for the person starting to group buy to get one of his own and not to make a serious profit on the deal. Most won't begrudge you for adding a few dollars for your trouble (repackaging for shipping and the like), but walking away with a few hundred $s is a no-no.

[Keith Outten]

Ross,

You can start a Want To Buy ad in the Classifieds Forum here and ask if anyone would like to share in the cost of purchasing cutters.
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[Mike Null]

Ross

In your listing I would be specific as the the size, diameter etc. as I'm pretty sure you won't get a discount for a mixed order.

You might also have a look at this place.

http://www.2linc.com/engraving_tools.htm