How do you sand your CNC carvings?

[Jim Underwood]

Gene, I'm familiar with the "machine rest" feature. Unfortunately I've not found it to be worthwhile. It causes more problems than it solves. I'd rather just go back with a smaller bit and recut the whole thing on a bias to the first cut.

Mike, this Komo remains pretty true most of the time. I think the last time I trammed it, I was good to a couple thousands in a 24" circle. And the spoilboard gets resurfaced about 2 or three times a month depending on how badly it gets cut up from running thousands of cabinet parts across it.

I think the solution is to stock sanding mops of some kind and get a Foredom tool to run them.

[Mike Heidrick]

Try one time to run it twice and see if I am crazy.

[Paul Phillips]

Or, if you decide to run it twice and have the time, try using a smaller ball-nose bit with 85-90% overlap.

[Shari Loveless]

Jim,
I've been sanding our carvings for quite a while now and I've used many different tools and done lots of testing of different methods. I always end up using my own homemade sanding mops that fit in my hand machine (hanging mastercarver with a foot control). The foot control is great for varying the speed of the mop rotations. I cut my strips of fabric backed sandpaper the right length, slit the ends, poke a hole in center, and then layer onto mandrel. Layers will vary from 4 to 12. I make some of them soft and long to reach into skinny areas, some short and thick for sanding around the outside edges of inset, and just average size and thickness for overall general sanding of the whole design. When I make the mops, I make six of each grit and size. This way I have enough to sand a couple of projects without interruption. I use 1/8, 1/16, 1/32 bits when we carve our designs. I don't want to lose any of it during sanding and our homemade mops work great. I tried the 3M bristles and didn't care for them that much...they have their own issues. Making my own mops and adjusting my speed and hand pressure gives me precise control over the process. I'm sure everyone has their own likes and dislikes. You'll just have to do some experimenting of your own to find what works the best for you. Each type of wood and carving will dictate it's own needs as well. Success is finding what does a suitable job and makes the process enjoyable.

[Jim Underwood]

Great info! Perhaps this old widebelt sander paper will serve in a second life. They are a little coarse though.
I do think an investment in a rotary tool is in order.

[Shari Loveless]

Just make sure you get one with a big enough motor to go the distance. I burned up 3 good dremels in short order before I got the mastercarver with the 1/2 hp motor. It's pretty much a large motor with a flex shaft attached but it can definitely handle all I've been putting it through. Those old belts should re-purpose nicely into mops.

[Jim Underwood]

I currently have a Dremel that is very lightly used. I understand they are easily burnt up. So I've not let anyone else use it. I've been looking at Foredom tools for the few carvings we do. I'd rather not burn up my personal tool for my employer.
I wish the boss was convinced we could make money carving. He doesn't want to spend money on tools or training/practice time for it. The sad thing is that every time I get a chance to make carvings they want it done quick. If you want it done quick you have to invest in those things beforehand.
When I made the mantel carving for our showroom it took two days for someone to sand it out. It would have been cheaper and quicker to run the 1/16th bit over the entire thing and buy a rotary tool and sanding mops.

[Viktor Zsigrai]

jim

it is very true... people thinking when theyre see the much machine time that by hand migth faster..
machine always cheaper than human workforce..

the restmachining really dont work, because wood is always in movement.

whne i had bad spots i calculated only around that area toolpath with smaller tool..
and set the smaller tool to the already milled surface.. close to the spot..

from gcode i got the x-y-z cordinata

moved the smaller ballend mill over and set manually the z value.. i dont know how it could work on your komo.. they are real big machines..

for your shop migth would be affordable a simpler cheaper machine only for finish machining.. even a machine runs 8-12 hour a small machine just use little power and one ball endmil.. way cheaper than any human workforce..

while your komo migth using 30 or more kw per hour a small machine migth runs with a few kw..

folks cant imagine a few palmsized carving if detailed, takes day to sand out by hand.. and bristles can sand out fine details..

[Russ D Wood]

I use the sanding mops from StockRoom Supply. They work really well. I use them in a powered hand drill so I can vary the speeds. Russ

http://www.stockroomsupply.ca/shop/s...77190b14794593

[bobby milam]

I have tried sanding mops but haven't mastered them yet as I remove more of the carved detail than the problem areas. I really like scrapers and recently bought on of these.

http://www.woodcraft.com/product/202...er-handle.aspx

It tells you on the package that they are useable out of the package but need to be sharpened for best results. They work pretty good for me. I am going to sharpen them this weekend and see how much better they get.

[Mark Smith61]

I was just about to ask if anybody had tried sandblasting. I was thinking a real fine grain sand and being very careful with the settings, but I never thought of using banking soda or walnut shells. I'm not that familiar with sandblasting other than some I did years ago to remove some rust on car parts, is the walnut shell something you can buy that is designed for sand blasters?

[Jim Underwood]

Holy Moly! Just got a look at the pricing for the 3M bristle discs...

They sell 'em by the case for $175:
http://www.shop3m.com/61500151594.ht...=POW_Marine_GS

Fortunately you can buy them by the each from McMaster Carr:
http://www.mcmaster.com/#abrasive-bristle-discs/=nx1ghr

[Bruce Page]

Also available on Amazon: http://www.amazon.com/s/ref=nb_sb_no...Bristle%20Disc

[bobby milam]

Holy Moly! Just got a look at the pricing for the 3M bristle discs...

They sell 'em by the case for $175:
http://www.shop3m.com/61500151594.ht...=POW_Marine_GS

Fortunately you can buy them by the each from McMaster Carr:
http://www.mcmaster.com/#abrasive-bristle-discs/=nx1ghr

Thanks for that link. I definitely need to order some and those prices are just right.

[Bruce Kinney]

Hello Jim, My personal experience with carvings done on my CWs has brought me to three primary aids for the finish sanding.

For step marks I go at the "finished carving" first with 4" diameter stacked sanding mop starting with 180 grit in my hand drill.

Next a set of small diamond coated riffler files about 3/16" wide. A quick internet search should show you several choices. These allow me to concentrate on areas that show heavy fuzzies the mop did not clean up and are more detail orientated than sandpaper alone.

Then back to my mops at 220 and 320m grit in the cordless drill. And finally fine adhesive backed sandpaper on a sanding pad to clean and smooth and large face planes and edges. This has brought my clean up time down to less than 1/2 hour for most plaques even with a high level of detail and routed edges to make them stain and finish ready. My apology in that I'm still rather clumsy learning how to post photos here.

IMG_0033.png.jpg IMG_0044-002.jpg IMG_0074-002.jpg