Why air drill?

[john_l]

I don't think I need one and I know the drill is available and I know many use them. But I don't feel I really understand exactly why.

I recently did a job where I was making cabinet carcasses out of melamine. I had many rows of holes for 1/4" shelf pins in each part. In my design files I just put 1/4" circles where they go, I then toolpathed it all in Vcarve to rout these holes at the depth I wanted along with the rest of the dados and perimeter cutouts. I toolpathed everything to just use a 1/4 end mill as the tool.

I ran the one file, quick and easy, all done with the holes and all.

Would a drill be faster? Keep me from ruining my spindle (if doing this day in and day out)? I know many shelf pins are 5mm and not the 1/4" ones I used.. so is that the reason?.. to save a bit change? Is there some other benefit?

[knight_toolworks]

it is to save wear on the spindle and speed. Plunging is harder on spindle bearings since they are designed for side load. if yi used a smalled bit and ramped it in it would be fine.

[kirkkelsey]

We use the standard 5mm holes for our shelves, and we also drill for the Drawer Slides and Door Hinge Plates. The addition of the holes for the hardware makes it more desirable to use a 5mm bit than 1/4" for shelf holes.

The Air Drill will allow you to cut Cabinets with all the 5mm system holes without having to change bits.

However, we are currently using a second router with a 5mm End Mill to do the 5mm holes rather than a drill. This allows the 5mm End Mill to be used to create a slightly larger hole for shelf hole liners, as well as the second head can have other bits installed instead for chamfering or other special tasks. A lot cheaper than a tool changer.

I have wondered about the wear on the router verses and air drill for doing a lot of holes. Is the greater versatility of using the router worth it? What would be the optimum 2 head configuration for doing cabinetry - Spindle and Router?

If the router is really the way to go for a second head, then I also have the same question - Why an Air Drill?

[Gary Campbell]

John..
We use an air drill along with a spindle to do cabinet components and I will try to answer your questions as they apply to our methods.
1) Quicker? actually I think slower. Drill has less power than spindle and endmills cut faster and cleaner.
2) Damage Spindle? "Official" reccomendations are that drilling be kept to a minimum, however, many out there are drilling both wood products and aluminum with little or no ill effects.
3) Save a tool change? Yes.. that is our main reason for adding the drill. Our best bit for the 3/4 and 1/2 dados is a 3/8" mortise compression bit. We use 5mm drill for shelf and hardware mounting holes. We also use a 1/8 bit for case assembly screw holes.

If I had to choose between a drill or a spindle for a second tool, I will choose the spindle and let the bearings be an expendable item. I will also tell you that we will be adding a second spindle with another drill. This will give us the flexibility to have 4 tools without a bit change and drop our machine time on the side panels from 4 min. 45 sec. per panel pair to under 3 min.
This is based on the way we process our side panels, which include: (for bases)
Top & back (only) single pass profile to size panel.
Blind .75w x .25 deep dado for bottom and top stretchers.
Blind .75w x .25 deep Pocket dado for drawer stretcher.
Full length .50w x .25 deep back dado.
5mm holes for up to 4 drawers.
5mm holes for up to 3 hinges.
10ea .125 assembly screw holes per side (thru)
Our drill is "Z" mounted (like the new SB drill) so we can control or change the hole depth from within the part file. We can also add retracts to clear bit on deeper holes without retoolpathing. (thanks to Mike Richards)
Here a pic.

6624
Gary

[wberminio]

I got an air drill because I don't have room for
a second Z (4x8 PRS Standard)and I wanted to the flexibility to not have to change to 5mm bit.
A second spindle would be ideal if possible.

[kirkkelsey]

What about a router vs. Air Drill as second Z? My understanding is a router bearings are better designed for the plunging involved in doing 5mm holes than a Spindle. Router vs. Air Drill because of the cleaner cut of a 5mm end mill vs. drill bit.

While I have doing designing and coding for others that own ShopBots, I have been listening and learning. Trying to determine that best configuration when I finally take the plunge and have to have a ShopBot of my own. The cost of a Spindle is such that I can probably only afford one, and I am convinced of the productivity improvements with a second Z that I really need to include that as well.

Only two years till my eldest grandson is 18, and I need to make up my mind by then in order get him setup properly to compete in the local cabinet market. This thread struck a chord in my quandary about how to go with my second head. I am fascinated by the reference to more than two heads and that possibility vs. expensive tool changers.

I have been sending designs out to CNC shops for years before I got involved doing coding for a ShopBot, and have to say that when comparing machines for a purchase of my own, that the ShopBot makes the most sense (with this forum and user base being a very strong deciding factor).

[john_l]

All makes sense to me. I think for the little volume I am doing with it for cabinets, I will opt to using a smaller bit and ramping in. At least for a while. If cab work gets to the point that I can justify it, I will look into maybe adding a drill. Thanks for all responses. Happy Thanksgiving.

[dingwall]

Gary, I think I understand the concept of your drill. I'm assuming you have a pneumatic slide that the drill mounts to. Air on causes the drill to drop down and start spinning. Air off powers off the drill and retracts the slide. Is that it? Brilliant!

Any detail shots available?

[Gary Campbell]

Sheldon..
You have mail
Gary

[beacon14]

The air drill is a great tool for those (like me) who have to drill hundreds or thousands of small holes. It's cheaper than buying a second Z-axis with a spindle. Yes it would be nice occasionally to have a second spindle/router but 95% of what I cut can be done with one bit and the air drill.

The air drill works as Sheldon describes, no second Z axis needed. The 5mm holes are cleaner in some materials than others but I've never had any complaints about the holes not being perfect.

I recently re-mounted my air drill on a shop-made mounting bracket. I'll post pictures when I get a chance.

[gene]

Hi
I checked on the air drill and shopbot told me the drill for an prt alpha is no longer available.
If it were i would like one also