Dust Shoe Prototype for the Carvetight

[henry1]

thank you for the reply will wait for your mpc file

[Sallen1215]

Dan this may be where i am going wrong, I use the jog to touch and touch the actual piece of acrylic, where your saying to jog to touch the carrier board and let it essentially air carve the second side of the file for the pipe and main dust shoe file. Unless im reading this information wrong, Would you be opposed to doing a video where you explain the process? You can use my mediafire server if the file is too large

[bergerud]

Dan this may be where i am going wrong, I use the jog to touch and touch the actual piece of acrylic, where your saying to jog to touch the carrier board and let it essentially air carve the second side of the file for the pipe and main dust shoe file. Unless im reading this information wrong, Would you be opposed to doing a video where you explain the process? You can use my mediafire server if the file is too large

If the acrylic was really 1/2 inch thick, touching both sides would be fine. My acrylic is only 12mm and the mpc assumes the thickness is 1/2. If I touched both sides, I would be carving 0.5-(1.2)/(2.54)=0.0275 too deep. You can touch one side but the other side needs a touch that is 1/2 inch from the touch that was on the first side. The carrier board takes care of that second touch since it is 1/2 inch deep. This is a good thing to let the carrier board take care of the depth independent of the actual thickness of the acrylic.

I am working on a new procedure (as I was commuting to work.) to do accurate (small) double sided carving independent of machine calibration. When I test it, I will start a new post.

The idea is this: Put in the carrier board and measure its length and width. Divide those numbers in half and write them down as the approximate coordinates of the center. Drill a hole using these center coordinates. (Use jog to center but plug in the numbers.) Now measure the distances from the hole to the sides of the cavity. Take that difference, divide by 2 and add (or subtract) from the approximate y center number. (Who cares about the x since it is constant when the piece flips.) You now have the y center coordinate required to carve in the center of the cavity. These coordinates can be used to carve many different parts as long as the carrier board stays in the machine. One chooses jog to center and instead keys in the same coordinates for each side of each carve.

It takes a little effort to set up but the results will be consistent and fairly machine independent. Many parts can be made using the same numbers. I will try it tonight.

[Sallen1215]

that explains why my pipes were carving too deep, my acrylic is 12 mm and even with the altered board demensions i still jogged the touch to the actual piece of acrylic, makes sense now also your x and y method seems sound. i need to get that method down and utilize it if it works like you say.

[bergerud]

that explains why my pipes were carving too deep, my acrylic is 12 mm and even with the altered board dimensions i still jogged the touch to the actual piece of acrylic, makes sense now also your x and y method seems sound. i need to get that method down and utilize it if it works like you say.

Did you alter the board dimensions or the depth of the carving? Altering the depth of one side (back was easiest) of the carving should have worked. Anyway make the carrier board as it will be useful to make a run of perfect parts!

I am just carving a part using the coordinate method. The hole was centered so I did not get to try the coordinate tweak. I have done that before with the sphere in the cube so I know it works to fine tune. It feels good when you start a new project, key in the coordinates and the bit goes right back to the hole (slides right in if you push the truck down). One button pushing mistake, however, and you have to start all over again.

[Sallen1215]

be sure to let us know how it goes

[henry1]

I just notice that when you used a board 14 in wide, the arm is in the way when the bit dips for mesearment it can't hit the sliding rail but ok for me , I don't use that wide to often , I cut the board to 13 1/2 wide and work good ,, still like the dust collection ausome

[bergerud]

I just notice that when you used a board 14 in wide, the arm is in the way when the bit dips for mesearment it can't hit the sliding rail but ok for me , I don't use that wide to often , I cut the board to 13 1/2 wide and work good ,, still like the dust collection ausome

I know Henry. I mentioned that a few times before. I thought that we could later make a bit plate which you manually fold up for those wide carves which are not done that often.

[JLT]

Finished my next version of the dust shoe variant, this one using a 0.8" I.D. smooth bore dishwasher hose from Home Depot. Using velcro power cord straps, I snaked the hose around the back of the machine, and sanded down some of the rubber "corrugation" on the hose to make a better fit through the top cover. There is still some rubbing going on with the hose as the truck moves to and fro, but doesn't appear to affect operations. The operation of the shoe during the initialization sequence also introduces manual steps (see http://www.youtube.com/watch?v=WBNHxRaiHSk, but please forgive the director for his first movie ; -) ). When I have more time and less projects, I'll work in a swing arm for the tapping of the bit, in order to minimize the manual intervention. For the time being, it's functional, and my next step is to put together an intermediate cyclone, as although the one gallon mini vac has plenty of power, it lacks capacity to house the vacuumed dust.


It's nice to finally have some dust collection...

[bergerud]

Nice work. Maybe you could use smaller hose if it was shorter. You know, short hose just to get out then a bigger hose.

You only need a small cyclone. See my cyclone for the dust cap made out of a pop bottle. I have been using it ever since I made it. I just looked in the mini vac after months of use and only found some pieces of tape, some large shavings, and a little dust.

I could not see a brush. Does you experience indicate that horse power eliminates the need for a brush? I remember thinking that no air flow from a vacuum could stop chips coming off of a 20,000 rpm bit. It seemed to me that the chips have to be physically stopped before being vacuumed up. (That is why I do not think the overhead type can ever really get all the chips.) Are you seeing any escape under the shoe?