Radius thousand of cubes

[scottp55]

We're doing kids blocks and using 1.75" hard maple blocks. We'll be doing thousands of these. I've been doing them with the small PorterCable router with the 3/16" roundover. We need to come up with the safest, easiest, faster solution as the people who will be doing this have a wide range of handicaps. I was going to make a 1.75 jig to hold 26, with enough space up top for the guide bearing and through cut with big dogbones on the corners with a downdraft table and a large offset base on the router, but the powers that be would like to eliminate the router. I might have posted some of this before, but if anybody has seen a unique approach,or a commercial method not to expensive. I would be very grateful. Thanks, scott:confused:

[gc3]

if...a true 3/16 radius is not needed, tumble sanding...an old dryer with heating element disconnected, strips of sand paper...

[scottp55]

Thanks Gene, I should have posted pics. Some of the graphics and letters are kind of delicate(never mind the Braille face). Could do before hand but jigging 130 of the little suckers is a challenge anyways and I'd like to keep edges square for that(never mind silica embedding itself in the wood?). Good idea for our uncarved building blocks.

[scottp55]

Oops, forgot to crop out my custom screws. Darn

[steve_g]

Scott...
Those screws are nothing special. I have some just like them!

SG

[scottp55]

I couldn't have hit those screw more dead if I had miked them. Just goes to show,don't embellish on the fly after a 12 hour day. Those screws are tricky little suckers, quick too!:)

[jerry_stanek]

You just have to train them not to jump in the way of the cutter

[curtiss]

You might want to use a laundry mat "tumble sander" rather than your home unit.

I would suppose it is a bit noisy so a midnight visit might be in order.

[feinddj]

I think the tumble sand is worth the experiment. I have been thinking about making some blocks and that is how i would finish the edges. I am going to use a five gallon bucket and sandpaper thrown in. Of course I will make a stand with rollers and a handle on the bot to make it more fun

[adrianm]

Saw a program the other night where they were tumbling hardwood handles with polishing pyramids.

Might get around the sand embedding itself?

[scottp55]

Well that was interesting, I now know all about laundromats. There was a link to this old house about tumble sanding small maple parts, the guy had tried several mediums and it wasn't working and he was asking advice too.
Would like a good clean radius, we did protos and went from 1/8 to 3/8" radius and did tests with dozen's of people and a clear opinion by almost everyone was larger had better feel.Went down to 3/16" because we need the room for graphics and touch readable fonts for blind. DID the ASTM drop test and then to put my mind at ease ran a dozen blocks in my dryer for two hours, checking at 5 minute increments for chips and splinters. LOUD! The larger the radius the better they held up(the drop test is a killer and the small radius fared worst.
As far as training people about tricky bits.......Let's put it this way, I'm in a wheelchair and have two nice scars on both knees from sawing "alittlebit" off the end(japanese pull saws are almost surgical compared to american). And I now wear a leather apron around the 'bot after 2 cutters "disappeared"during bit changes(I was sitting on them). Thanks for the suggestions,keep em coming:)

[scottp55]

Thanks Adrian, page 5 google search looks interesting saw your "pyramids" but also saw ceramic and ceramilite? angled rods that look interesting as well as triangles. We'd been thinking vibratory tumblers for the fuzzies on wood buttons but hadn't gotten to the purchasing stage(were going to use walnut shell until reminded about nut allergies in toddlers, that's why we're not using tung on those.may try home experiment on a couple of these on maple. https://www.ishor.com/TumblingMedia.php

[myxpykalix]

It would seem to me that tumble drying would cause way more nicks and "bruises" in a large dryer so you might try this.....

Firstly this is just an idea that came to mind i've never tried this but since i'm cheap i'd try this.
See if you can find and old, cheap vibrating type sander. Get a small metal bucket (not a plastic one). Remove the sanding head from the sander (usually 2 or 3 screws). Then drill the corresponding screw pattern in the bottom of the bucket and place a thin piece of gasket or rubber material and attach the bucket to the sander.

Get some type of rough material (maybe coal??) or something to act as your sanding medium. Then you have a cheap vibrating sander that might be more gentle to your parts.:eek::confused::D

[gc3]

we have an old dryer with no "fins" on the barrel...parts stay on the bottom...no dings and dust is exhausted out the back vent...works well and it's great to hear clients come to the shop asking "what's the dryer for?"...

[scottp55]

Gene, what are you using for a medium? May try paint can on two boat trailer rollers and a motor for a test trial for our plain blocks. maybe Jacks method with an old makita. Will make router jig with bigger plexi base plate two require two hands and run the actual set up by them. Thought somebody might come up with something where you fill the hopper at night, flick a switch and BINGO finished in the morning. Maybe if I left the blocks out with milk and cookies the Brownies would do them. :)