DIY bench anchors

[Mgildersleeve]

This is a video of bench anchors I use to hold jig bases down to my assembly table, etc. They are omnidirectional expanding bench dogs that I’ve shown before. They are basically self centering, depending on one’s ability to drill holes in the center of dowels. I don’t have a lathe. I used Matthias Wandel’s horizontal routing machine for the center bores. It’s not perfect allignment,  but it gets the job done real close. This is just a video I made while I made the latest batch. They are handy and cheap to make.

 

[Dick Mahany]

You have done a fine job on those dogs and thanks for sharing.  I have been using a similar technique for years, derived from the expanding miter slot runner flexure joints with great success. I did make a few lathe turned/ bandsaw sliced flexure joints a while back, but your execution of undercutting the base of the fingers is brilliant, thanks for posting and NICE JOB !

BTW your manufacturing technique is well documented and can be expected to be replicated many times over.  Very practical.

 

[Z48LT1]

What dowels do you start with?

 

[Corwin]

Nice job on your bench anchors. And a great video showing your process.  [thumbs up]

I use Cam Clamps on my expanding dogs. You may like these much better than those knobs.

 

[Mgildersleeve]

Corwin,  thanks for the cam clamp advice. I have one sitting on my shelf waiting for me to test it out. It seems like a nice piece. I just haven’t gotten around to trying it out. Good to hear good things about it. Maybe I’m getting stuck on using known proven things and not expanding my horizons.

Dick, I wish I had a lathe and lathe knowledge. From what I’ve seen, that’s the proper way to center bore a dowel. I’d love to hear about any other ideas on the matter. It bugs me that I can’t get it down more exact.

Z48, I use 3/4” dowels. I looked for 20mm dowels online and couldn’t find any. I made a full sheet of mdf with the hole system bored into them with 3/4” holes. I have a routing template described on a previous post that makes this exact and simple and very quick. Then, I cut off pieces from that sheet as I need them for bases for jigs.

 

[Dongar]

What I have done in the past is clamp a board to the drill press table,drill a hole the size of the dowel, replace the drill bit with one the size of the hole you want, put the dowel in the previously drilled hole and drill the centered hole in it. This gives a hole pretty close to centered.

 

[FastEasySmartTOOL]

Seriously clever! Great design [thumbs up]

Thanks for the video.

 

[Mgildersleeve]

Seriously clever! Great design [thumbs up]

Thanks for the video.

Thanks, man.  I love your work, by the way.

 

[Mgildersleeve]

What I have done in the past is clamp a board to the drill press table,drill a hole the size of the dowel, replace the drill bit with one the size of the hole you want, put the dowel in the previously drilled hole and drill the centered hole in it. This gives a hole pretty close to centered.

Thanks.  I tried this last time with poor success.  Maybe I should try it with a forstner bit next time.

 

[fritter63]

Cool design, I was just thinking about how to do this last night.

Have you considered 3D printing them? I think they'd work good in laser sintered nylon from Shapeways.com. If you don't mind, I think I might take a gander at drawing up them up in CAD and try it out.

 

[Svar]

Cool design, I was just thinking about how to do this last night.
Have you considered 3D printing them? I think they'd work good in laser sintered nylon from Shapeways.com. If you don't mind, I think I might take a gander at drawing up them up in CAD and try it out.

I'd rather machine them just like the OP did, but from delrin/acetal rod.
Machining is much faster than 3D printing when it comes to simple symmetric forms. Not to mention the choice of materials.

 

[fritter63]

I'd rather machine them just like the OP did, but from delrin/acetal rod.
Machining is much faster than 3D printing when it comes to simple symmetric forms. Not to mention the choice of materials.

That may be true for FDM "home" printing, but the laser sintering approach is much faster esp when you just hit "buy" and wait for it to arrive...

Here is my initial design. I sized this one for 20mm holes and a 5/16 bolt since I have a bunch of female knobs in that size already. It is fully parameterized though so I can customize it in seconds.

Uploaded to Shapeways, it's $6.97 per in any of the nylon colors but white (one dollar more for some reason). Compare that to $14 for a similar part from Lee Valley (http://www.leevalley.com/us/Wood/page.aspx?p=59754&cat=1,41637) so I think that is pretty good.

Could also print it in aluminum for $95... ;-)

I may just have one printed to see how it works.

[member=66433]Mgildersleeve[/member] being sure to honor you and your original design, I won't try to sell these or anything but if you're open to it I can make these available for purchase directly from Shapeways with no markup.

 

[Vondawg]

The Lee Valley ones use a big honking 1/2” bolt  [sad]
@Fritter... can you help out an old fart out who has no idea what Shapways is or where to find it....I’d like to try these
Thx

 

[fritter63]

The Lee Valley ones use a big honking 1/2” bolt  [sad]
@Fritter... can you help out an old fart out who has no idea what Shapways is or where to find it....I’d like to try these
Thx

Ah, I didn't notice that!
http://www.shapeways.com is a 3D printing service that allows you to upload 3D cad files (created with something like Sketchup or Fusion 360) to their site and submit them for printing. They have a TON of materials available in laser sintering (a laser heats and fuses powder one tiny layer at a time to form a solid). Laser sintered nylon is mostly what I use, as they call it "Strong, light, and flexible.

I've printed things from the RO-90 "disk mounter" tool (helps line up the holes when using the foam interface pad), to spacers (so I can use my festool table clamps on a 1/2" thick surface), to hooks and such (mounted on my boom arm).

They also offer more traditional FDM (Fused Deposition Modeling) in PLA (like you do with a home 3D printer.

As I mentioned, they also offer metal printing, so can you do aluminum if you want. (obviously, not the same finish as a billet CNC'd part). I've also used it to 3D print parts for my CNC machine ("Machines making machines? How perverse!").

The coolest thing is that you can upload your models and  make them available for purchase online (you create your own store front), you don't have to do a thing except specify the markup.

here is the link to my store:https://www.shapeways.com/shops/smartjigs

As I said, will have to print a prototype and wait to hear from [member=66433]Mgildersleeve[/member] before I make it available.

 

[Vondawg]

Many thanks!

 

[fritter63]

Bump to point out the 3D printed versions of these [member=66433]Mgildersleeve[/member] and I have developed:
http://festoolownersgroup.com/festo...inted-self-clamping-bench-dogs-available-now/