Micro-Edge Sander

[wefalck]

Although I recently constructed a micro-grinder and –sander (http://www.maritima-et-mechanika.org/tools/microgrinder/microgrinder.html), I found that some hand-sanding device would be desirable for very delicate operations. Sometimes just a few strokes would be sufficient and the process would be difficult to control with a motor-driven machine. A guided sanding block allows to achieve flat and square edges.

 

 

After some rummaging in my collected stocks I found a piece of aluminium rail with a T-slot at one end (I don't remember its original purpose), a piece of thick aluminium sheet, some square aluminium stock, and a well-seasoned piece of pinewood of just the right dimensions (5 cm x 8 cm x 2 cm).

 

 

Holes were marked out, drilled and countersunk for the pieces to be screwed down onto the wooden block. The four sides of the wooden block were squared off in the milling machine with the aluminium pieces in place. The wooden block then was carefully levelled in the machine-vise and a slot milled into the aluminium as a guide for the sanding block. Finally the surface was evened with some light cuts with a fly-cutter.

 

 

A mitre-guide was fashioned from a piece of flat steel. It can be mounted left or right and in different configurations.

 

 

The sanding block is fashioned from some 8 mm x 8 mm square aluminium stock. It has shallow recesses milled into both sides to allow for the thickness of the sanding paper. A knurled screw M3 serves as handle. to begin with a glued a strip of 600 grit wet-'n'-dry paper onto one side and a strip of plastic coated with abrasives as used by dentists for grinding and polishing teeth onto the other side.

 

[WackoWolf]

Excellent work, this would come in handy for our hobby.

[Mark P]

Thank wefalck for posting this.  An ingenious little device,  with its construction clearly described.

 

All the best,

 

Mark p

[BANYAN]

Hi Wefalck, some very nice machining; but, we have become accustomed to that from you

 

This is a well designed and made compact tool for the precise sanding of small pieces/parts.  One question though, if I may?  How do you secure the piece be sanded so that it does not move while sanding.  The mitre will assist, but even the slightest movement can have disasterous results on very small pieces.  Do you intend fitting hold-downs or such or do you use a non-slip under-pad with the part?

 

cheers

 

Pat

[wefalck]

You are right about holding down pieces. In many instances I found my fingers the most versatile clamps, actually 

 

I have been thinking about this, but left it to the actual practical experience, to see what is needed. For very thin strips and wires I made a little holding device for the micro-grinder a while ago, that I can also use on this contreivance here:

 

 

If I was to make this gadget again, I think I would change the design sligtly. Rather than having the sanding block moving in a channel, I would make some sort of rail and cut a slot into the sanding block that engages with the rail. This would give more flexibility in the kind of sanding tools to be used. For instance, I am thinking of adapting a fine diamond nail-file for the purpose. I have used such nail-files for decades in my workshop as they give a very smooth finish. However, I am not sure how cut the files to size and drill them without ruining my tools 

 

Anyway, this is a first attempt at miniaturising a gadget I saw somewhere and adapt it to my small-scale work.

[Bill Tuttle]

Wefalck,

 

Great idea and nice picture.  Think I should get to work on one of these.  What is the diameter of the disc?  Just trying to bring the size into perspective.  Also really like your new guided sanding block.

[wefalck]

The sanding disc has a diameter of 50 mm (2"). More details on the micro-grinder can be found here: http://www.maritima-et-mechanika.org/tools/microgrinder/microgrinder.html

[Bill Tuttle]

wefalck,

 

WOW great website and excellent instructions as usual, will put this on my growing list of things to do.  I appreciate your help.