# DIY solution to guide bush size issue



## charlesb (Jun 15, 2011)

I purchased two secondhand Hafele jigs, but of very recent manufacture, including a drainage jig, and found that the size of all the guides was approx 31mm. Using a 30mm guide bush, the router tended to go from one side to the other, a drift of about 1mm, which was unacceptable for perfectly straight lines, e.g. with the drainage jig. Also when using a large cutter to cut a 40mm solid wooden worktop, the router was very difficult to control because of the sideways movement, leading to damage to the side of one of the guides, which I will now have to repair. :angry::angry::angry:

No-one sells 31mm guide bushes. In order to get a closely fitting guide-bush, I had to adapt a 32mm steel bush. I fitted it over the end of a hole-saw of appropriate size, bound with tape to make a closer fit, and spun it on a drill. At the same time I used an angle grinder to grind it down to 31mm, to produce a snug fit in the guides.:happy:

Did I miss something? Why don't they make bushes of the right size to fit the jig guides?


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## harrysin (Jan 15, 2007)

How about gluing strips of Laminex to the inside edges of the template to take up the play with the 30mm guide/


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## Phil P (Jul 25, 2010)

charlesb said:


> I purchased two secondhand Hafele jigs, but of very recent manufacture, including a drainage jig, and found that the size of all the guides was approx 31mm. Using a 30mm guide bush, the router tended to go from one side to the other, a drift of about 1mm, which was unacceptable for perfectly straight lines, e.g. with the drainage jig. Also when using a large cutter to cut a 40mm solid wooden worktop, the router was very difficult to control because of the sideways movement, leading to damage to the side of one of the guides, which I will now have to repair.
> 
> Did I miss something? Why don't they make bushes of the right size to fit the jig guides?


Hi Charles

That is actually correct, you _did_ miss something. If the slots were 30mm then the guide bush would probably jam in the slot at some time. The extra 1mm or so allows for a bit of slack to make sure this doesn't happen - this is exactly how a kitchen worktop mason's mitre jig works. If the router is going from side to side then I'm afraid it is you who is to blame. The cut running away from you, the first cut, needs to be made with the router pressed firmly against the left hand side of the slot. The return cut, the cut coming back to you, is made with the router pressed firmly against the right hand side. At the end of making the cuts the drain slots are sanded out to smooth them off and remove any machining marks. It is really very straightforward and I've done this task quite a few times with both solid wood and Corian worktops. If you are having difficulty controlling the router then I suggest that you make a couple of lighter passes before going to a full depth pass as ball nose (cove) cutters used in these jigs do tend to deflect when plunged in to full depth. The jigs are designed for use with a plunge router only and are unsuitable fot fixed base routers and to avoid further damage I'd suggest that you retract the cutter at the end of a cut before lifting the router off the jig (the most common mistake made by people when using worktop mitre template jigs, for example). 

BTW these jigs are manufactured from HPL (high pressure laminate, or a form of phenolic plastic) and can be easily repaired using Araldite (epoxy) which is filed and sanded after it has set (at least 24 hours). Even us pros get it wrong sometimes!

PS Another tip: Wax your guide bush with a little bit of candle wax before making a series of cuts and you'll find it all works a lot smoother and it will be easier to make that perfect cut

Regards

Phil


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## charlesb (Jun 15, 2011)

harrysin said:


> How about gluing strips of Laminex to the inside edges of the template to take up the play with the 30mm guide/


Far too much effort, especially with the curved guides!! My solution works pretty well for my purpose. The nice tight fit stops the router from moving around.


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## charlesb (Jun 15, 2011)

Phil P said:


> Hi Charles
> 
> That is actually correct, you _did_ miss something.


I thought I had.



> If the slots were 30mm then the guide bush would probably jam in the slot at some time. The extra 1mm or so allows for a bit of slack to make sure this doesn't happen - this is exactly how a kitchen worktop mason's mitre jig works. If the router is going from side to side then I'm afraid it is you who is to blame. The cut running away from you, the first cut, needs to be made with the router pressed firmly against the left hand side of the slot. The return cut, the cut coming back to you, is made with the router pressed firmly against the right hand side. At the end of making the cuts the drain slots are sanded out to smooth them off and remove any machining marks.
> 
> It is really very straightforward and I've done this task quite a few times with both solid wood and Corian worktops. If you are having difficulty controlling the router then I suggest that you make a couple of lighter passes before going to a full depth pass as ball nose (cove) cutters used in these jigs do tend to deflect when plunged in to full depth.


OK thanks for the tips. Whatever you do, you need to be strong to control the router with big cutters and 40mm worktop even doing it the correct way. The forces exerted by the cutter are quite large. Exacerbating the problems was the matter that I wasn't cutting the whole depth but gouging out about 3/4 of it.

With the Imm gap, the router can easily tip from the vertical, if you decrease the force on it even slightly. And that worktop is expensive, even the bits I bought off ebay. With my tight-fit solution, the router doesn't tip nearly so easily in the guide. In fact I think it is a good innovation.



> The jigs are designed for use with a plunge router only and are unsuitable fot fixed base routers and to avoid further damage I'd suggest that you retract the cutter at the end of a cut before lifting the router off the jig (the most common mistake made by people when using worktop mitre template jigs, for example).


Good ideas. Thanks.



> BTW these jigs are manufactured from HPL (high pressure laminate, or a form of phenolic plastic) and can be easily repaired using Araldite (epoxy) which is filed and sanded after it has set (at least 24 hours). Even us pros get it wrong sometimes!


I was going to use high strength plastic-metal i.e. car body filler. I guess its a similar sort of thing. 



> PS Another tip: Wax your guide bush with a little bit of candle wax before making a series of cuts and you'll find it all works a lot smoother and it will be easier to make that perfect cut
> 
> Regards
> 
> Phil


Thanks.


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## harrysin (Jan 15, 2007)

Phil P said:


> Hi Charles
> 
> That is actually correct, you _did_ miss something. If the slots were 30mm then the guide bush would probably jam in the slot at some time. The extra 1mm or so allows for a bit of slack to make sure this doesn't happen - this is exactly how a kitchen worktop mason's mitre jig works. If the router is going from side to side then I'm afraid it is you who is to blame. The cut running away from you, the first cut, needs to be made with the router pressed firmly against the left hand side of the slot. The return cut, the cut coming back to you, is made with the router pressed firmly against the right hand side. At the end of making the cuts the drain slots are sanded out to smooth them off and remove any machining marks. It is really very straightforward and I've done this task quite a few times with both solid wood and Corian worktops. If you are having difficulty controlling the router then I suggest that you make a couple of lighter passes before going to a full depth pass as ball nose (cove) cutters used in these jigs do tend to deflect when plunged in to full depth. The jigs are designed for use with a plunge router only and are unsuitable fot fixed base routers and to avoid further damage I'd suggest that you retract the cutter at the end of a cut before lifting the router off the jig (the most common mistake made by people when using worktop mitre template jigs, for example).
> 
> ...


You are so right Phil., I must have been having a seniors moment when I made that post. In several of my photo-shoots I've shown the template to be about 1mm wider than the guide in order to make a final light cut.


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## Phil P (Jul 25, 2010)

charlesb said:


> With the Imm gap, the router can easily tip from the vertical, if you decrease the force on it even slightly. And that worktop is expensive, even the bits I bought off ebay. With my tight-fit solution, the router doesn't tip nearly so easily in the guide. In fact I think it is a good innovation.


I think that there's the issue. If you can tip the router easily then you aren't pressing the guide bush against the left side of the slot and/or supplying sufficient downwards pressure. Using jigs like these does take a reasonable amount of force, but it's hardly in the same league as mortising door locks with the door hung in the casing. I suspect that may also be taking too deep a pass and possibly that your cutters may not be ideal for the task. Are the carbide tips vertical or do they have an angled "set" to them? The latter type work far, far better, but generally cost more. Another approach might be to make a first cut with a smaller diameter bit before using the full size cutter; by hogging away some of the bulk the final cuts will take less effort. 

I've done this sort of task on Corian worktops (which can be a lot more difficult to rout than hardwood) using Trend Craft Pro cutters (hardly industrial quality, but better than cheap bottom of the barrel cutters) without any of the problems you have had, hence my comments

Innovation or no I still can't see many real tradesmen queueing up to use your solution. 



charlesb said:


> I was going to use high strength plastic-metal i.e. car body filler. I guess its a similar sort of thing.


Well, no it isn't, actually. Epoxy is rigid, car body fillers are a two-pack compound with a large amount of bodying compound (mineral fillers) and are designed to have an amount of flex or "give" in them. They are softer and may not adhere properly to HPL. At the end of the day Araldite costs under a tenner ($15) which is nothing to pay to repair a £60+ ($100) jig

Regards

Phil


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