Shaping Small parts using AIR hold down.

Boys and Girls,

 

I posted this gizmo in a review of what I call Air Dogs, however, I feel that my adaptation has egged me into posting this as a project… not as any “item created” but more so as a procedure of how I tried using the dogs on small parts.

 

For the Aussies out there … It’s not a Review… no it’s not an everyday Review… NO, there’s no Review, no Review, just a  Project, an everyday Project!... and I won’t repeat this for a Blog.  

 

In my review, I just tried to,

now I’ll try to go one step further,

 

Not bragging about our standard males’ 159mm (6 incher), I know my limitations, and am into pursuing miniaturisation… how low small can I go?  

 In pursuit of my optimum goal, I was prepared to play around… with… different small sized packers that support/pack the wood above the air dog placement.

 

My first cut (lasered)

was 25mmOD x 19mm ID,

and just about got sucked into that black hole. Upped the ante 

to 30mm OD and 19mm ID,

and it seemed OK to hold this little test piece of 24mm x 22mm x 16mm,.

Let’s see how good the Mirka is?

flipped it once (across the room), however, probably due to non-horizontal ROS application (makes sense if you’ve read the review and if not go and read it), after re-mounting and ROS zapping,

… smooth as a… hmm for political correctness, shaved cats fur… hell that sounds worse than my first Philistine intention.

 

Was not gruntled with the results and I put on my antartic intarsia hat and wondered if it could handle a modicum of abuse. Dragged out my Foredom, which was still mounted with my rifle stock carving bit 

and gave it a bit of punishment,

OK, the Foredom did a Cape Canaveral impersonation and launched that little sucker 5 times into the stratosphere and had me on all 4rs ferreting it down. The last launching had me pissed, thinking I couldn’t find it to report/photograph on its progress… I found it,

Not pretty and lots of sawdust/Foredom_fodder around it… when you consider that sawdust (most cleaned away for the photo shoot) and the scars on that little bugga, I feel that the pressures exerted met with reasonable resistance to be of benefit in future small parts projects. 

Analysing the results, I started off gently, but as I got complacent, exerted more and more pressure with the Foredom, which is what created the missiles every time. 

 

I made a video 

of the operation and you may notice (and I also heralded it) that pressure on one edge of that small piece with the sander, broke the seal and dislodged the hold… so keep the bloody ROS horizontal… also had issues holding a piece that was cut straight off the bandsaw without any cleanup… but then again that is what I’m trying to do… initially I would tidy up one side with my air cups on the upside down ROS. 

 

On later experiments, I found that larger ODs minimised the uneven pressure on the perimeter… minimise, not necessarily eliminate, and the perimeter of the packer extending past the object served my purpose better.

I made a pad 40mm OD and 20mm ID

and tried a 32mm diameter LBD $1 coin (legal tender in my house) for holding,

and was quite surprised at the holding power through the porous 3mm MDF.  Expose it to my Mirka,

 

No, no one wiped the smirk of my dial, but it was the reverse face with leftover laser char marks. Hit it with the Mirka (240G) and if my face (obverse side) was on it, it would be clean shaved,

I did push my luck with a 23mm diameter piece,

 

Not much luck with the ROS, though the added height may have played with the equilibrium, however, I blasted it with full power of my Ryobi blower, 

which would have sent the blue Rockler mat flying,

if not for the weight of the Mirka… and it stayed put. What does that prove?… bugga all.

 

As a final pitch, I made up a 40mm OD x 16mm ID packer and continued to abuse that small piece with my Foredom. The holding power increase significantly.  Launched it once, but this picture may give an indication of the extremes I went to,

and was not surprised when the burr accidentally got dug in… just ignore my carving prowess. 

That attempt was amateurish even for me so I decided to push it a tad further.  Back in the workshop, I set up a configuration that could get the job better into focus and positioning for the Foredom, 

You can get a better impression of the procedure I tried through this quick video,

however, to fast track, this is how it finished up after more “burring” and 240G sanding,

Also consider the size of the sacrificial pieces I used in the videos as compared to my $1,000 coin, 

 

 

Would I buy more? I feel the two I have are enough… even though I love convenience, they are easy to move and being “single streamed”, it’s just as easy to move the dog as I would have to move the cabling and the vacuum pump… furthermore, if I needed a bigger holding footprint, I would use my Fe$tool VAC-SYS or a combination of my Rockler air pods.

I started drafting this yesterday, but after editing the video for posting, I said bugga it, get 2 more for convenience… tried to place am order this morning and they no longer ship to Aussieland.

 

For all you other foreigners, the dogs are available from here, and you will need  a vacuum pump and many accoutrements, so carefully consider whether you want a life of ease or struggle with workarounds. 

 

Ugh!!! Just realised… bloody metric… if I went imperial, ¾” dogs would permit me to mount a 1mm x 1mm smaller item… BAH-HUMBUG!