# Making dovetailed runners?



## DennisCA (17 Sep 2015)

My saw has non standard slots for dovetail runners. I'd love a plain 3/4" or 19mm slot instead of this german "uniqueness" as buying a guide bar from the manufacturer is 82 euros + shipping & handling. But here I am.







Anyone know a way I could accurately grind down a metal bar to properly fit these slots? I was thinking of ways to regrind the slots themselves but modifying the a bar is probably easier and no risk of messing up the saw. I could go at it with an angle grinder I guess, but it'd be difficult to get a proper fit.


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## flh801978 (17 Sep 2015)

It will be quite easy to do
just start with a bar the max width and grind the sides down at the required angle untill it fits in the slot
Just go slow

I'll mil you one for 30 euros and post at cost if you let me have accuurate dimensions


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## damo8604 (17 Sep 2015)

flh801978":9tkkc7g5 said:


> It will be quite easy to do
> just start with a bar the max width and grind the sides down at the required angle untill it fits in the slot
> Just go slow
> 
> I'll mil you one for 30 euros and post at cost if you let me have accuurate dimensions


Result! =D>


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## DennisCA (17 Sep 2015)

30 euros is much more than I am willing to pay as well. I'll go look at the scrap yard some day to see what I can find and try angle grinding.


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## DennisCA (18 Sep 2015)

This is giving me ideas, probably bad ones
milling-cast-iron-with-a-hand-held-router-t75735.html


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## Retire2004 (18 Sep 2015)

Hi Dennis,
The solution is actually starring you in the face! Mount a metal cutting disc (angle grinder disc) in place of your saw blade, using appropriate spacing washers etc. Tilt the disc to the dovetail angle and slowly feed the metal strip past the rotating disc. Turn end for end and repeat using fine adjustment on your rip fence (or shimming) until you have a good fit in the dovetail slot. (Take appropriate health and safety measures). Some people grind planer blades in this way!
Kind regards,
Tudor


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## beech1948 (18 Sep 2015)

An angle grinder should work to remove 90 percent of the excess if you can make a jig to hold it at a fixed angle to pass the metal against. Then finish the last 10 percent on coarse wet and dry going finer as you get close to final dimentions.

A jig could be made flexible if you incorporate an M12 screeched as an adjuster to alter the angle if it needs fine tuning.


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## DennisCA (18 Sep 2015)

Retire2004":htgzn7p0 said:


> Hi Dennis,
> The solution is actually starring you in the face! Mount a metal cutting disc (angle grinder disc) in place of your saw blade, using appropriate spacing washers etc. Tilt the disc to the dovetail angle and slowly feed the metal strip past the rotating disc. Turn end for end and repeat using fine adjustment on your rip fence (or shimming) until you have a good fit in the dovetail slot. (Take appropriate health and safety measures). Some people grind planer blades in this way!
> Kind regards,
> Tudor



Running into a bit of the same problem as when I tried to make wooden ones, right tilt blade, tilts toward a fence that cannot be put on the other side of the blade. Quite dangerous a cut to make on such a small piece and on the 2nd cut I have the angled edge towards the face of the fence giving me an extremely slim bearing area. I don't think I ever finished a cut when trying this with wood.


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## Retire2004 (18 Sep 2015)

OK Dennis, I appreciate your safety concerns. So how about if you cut a recess in a hardwood batten and clamp (or screw) your metal blank to that. You could angle the side of the recess for the second cut to give more support to the narrow edge.
Tudor


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## Droogs (18 Sep 2015)

Have you thought about using UHMW (Ultra high Molecular wieght) platic which can be worked with a router to the desired size/shape and has the added bonus of being an ultra low friction surface.

you can see some here:

https://www.youtube.com/watch?v=nl8EZtbhxQs


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## DennisCA (19 Sep 2015)

Not UHMW but I have thought about a router to shape the material but I don't have anything for the proper angle and with my new router I cannot yet use my homebuilt tilting lift. TBH I am thinking of removing just the tiniest bit of material from the top of the runners (it is worn and uneven anyway and unusable) to see if I can get an slightly better bearing surface. I wouldn't need much to allow for a simple rectangular runner, and I could still use the dovetail style as well.


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## pcb1962 (29 Sep 2015)

DennisCA":1fts3u57 said:


> Running into a bit of the same problem as when I tried to make wooden ones, right tilt blade, tilts toward a fence that cannot be put on the other side of the blade



Can't you just clamp a piece of wood or metal bar to the table the other side of the blade to act as a temporary fence?


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## MusicMan (19 Oct 2015)

The cheapest would be to file it by hand. Good technical exercise, too.


Keith


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