# Homemade Katsu Jointer Jig



## Rorschach (5 Dec 2017)

Following on from my homemade router table post;

my-first-router-table-t108628.html

I wanted to see if I could come up with a jointer style setup that was also super simple and easy to use. Because of the design of my fence I was able to simple turn the fence end for end and use the reverse side as the jointer fence. It was trued up by hand at the bench and the area for the cutter was nibbled away in a few passes. I then used a strip of worktop edging that was in my scrap bin as my offset on the outfeed side. Not only was it a nice thickness of 0.5mm, it is also smooth and flat. It was glued onto the outfeed side and the edges were rounded to stop it catching anywhere.
The cutter is a cheap chinese 10mm x 75mm bit which I trimmed down with an angle grinder as it was too long for my needs and the thought of spinning it up was terrifying. 
There is a theoretical material capacity of 45mm though I highly doubt I would ever do that and I am not sure it would handle it anyway but the test cut on a piece of 20mm stock went very well and it is shown in the pictures. It's very easy to setup just using a straight edge, takes seconds and the small depth of cut of only 0.5mm means it doesn't seem to stress or even slow down the katsu at all in use. 
Dust extraction near perfect as well.


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## galleywood (5 Dec 2017)

Sorry if this sounds harsh but your pics don't do your efforts justice.
Could you post some more so that we can appreciate what you have done.
Regards


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## Rorschach (5 Dec 2017)

I'll sort something out tomorrow. I thought it might be rather self explanatory using the pics from the first thread but I guess you are right.

FWIW I did a test on 45mm stock and it does actually have the power to make the cut however there is too much compounded error between the router, base plate, jig and cutter for it to be useful unfortunately. The cut is almost 0.5mm out of square at the top edge of a piece of 45mm stock. Considering it is a 1/4" cheap router in a homemade jig, I am surprised it isn't worse. I only ever expected to use this on materials of 25mm or less and for that the cut is plenty square enough for my needs as I was really intending it more to get an edge straight rather than square as my hand planing technique is poor to say the least lol.


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## sunnybob (5 Dec 2017)

I think youll find most of the error is in your "It was trued up by hand at the bench" stage. 
I've made three adjustable offset fences by hand, using all sorts including melamine faced stock and even an architectural aluminium post as a backing. None of them worked well despite many hours of "truing up".
I finally gave up and bought a UJK pro router fence this summer. Why oh why didnt i do that 18 months ago? 
It takes very fine tuning adjustments to stop end snipe, but now the wood is as clean as factory cut and I've cut 30mm thickness.


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## Rorschach (5 Dec 2017)

sunnybob":3fatd3k0 said:


> I think youll find most of the error is in your "It was trued up by hand at the bench" stage.
> I've made three adjustable offset fences by hand, using all sorts including melamine faced stock and even an architectural aluminium post as a backing. None of them worked well despite many hours of "truing up".
> I finally gave up and bought a UJK pro router fence this summer. Why oh why didnt i do that 18 months ago?
> It takes very fine tuning adjustments to stop end snipe, but now the wood is as clean as factory cut and I've cut 30mm thickness.



No the fence is fine, checked perfectly square against the table. The router spindle however is not perfectly square in it's base and there there is some error in the grinding of the blades on the cutter, these compound together so that it cuts more at the top than at the bottom. Using a better cutter will help and I may be able to shim the base slightly to compensate also but I am not sure if I am going to do that yet, first I need to see how much I will use this jig and if those errors cause any trouble in the work I do.


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## drewdt3 (6 Dec 2017)

Cracking idea! On a side note, I have Katsu router and it is incredibly loud and gets very at the tool holder. Is this just mine or is yours the same?

Drew


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## Rorschach (6 Dec 2017)

drewdt3":35xjzz2e said:


> Cracking idea! On a side note, I have Katsu router and it is incredibly loud and gets very at the tool holder. Is this just mine or is yours the same?
> 
> Drew



I have nothing really to compare it to but I don't find it overly loud. I always wear hearing protection with using any power tool anyway, and quite a few hand tools as well. The only exception being the metal lathe which is quieter than the radio lol.


Did some more testing this morning, the router is definitely slightly out of plumb in the body but only a fraction, not enough to cause any trouble for most things. The router, table and fence are all about as perfectly square as I can manage/measure. There is some error in the cutter and I think that the cutter may also be flexing a tiny amount since it is so long and thin. Have improved the results slightly but the jointed edge while flat, is not square except on thinner stock.

I think I will mark this down as a partial success. There are limits in the router and I am pushing it to the edge (get it) in regards to jointing. I think honestly it just is never going to handle more than 1/2" maybe 3/4" stock for this job, but that's fine, it was an experiment, it cost me a few hours of tinkering and a couple of quid. No damage was done to the original table and fence and that setup works really great.


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