Is a 25mm guide bush ok in my jig?

mattbowman81 · Post by **mattbowman81** » Sat Oct 10, 2015 7:01 pm

I've stupidly come to work away for the weekend, and left my trend universal base and 30mm collet at home. I need to finish the worktops by tomorrow, and no where has anything in stock to fit my makita router.
I have a 25mm guide bush, which will fit on my router. My thoughts are that as long as tho bush keeps to the correct edge of the jig, everything should cut and fit together fine.
Any thoughts?

Thanks :)

Timllfixit · Post by **Timllfixit** » Sat Oct 10, 2015 7:54 pm

You would have the problem of the bush being loose in the slot, so you would have to go steady and keep it over to one side or the other. Don't forget the cut will be 2.5mm out compared to usual.

mattbowman81 · Post by **mattbowman81** » Sat Oct 10, 2015 8:00 pm

Thanks for the quick reply. I thought it'd be a couple of mm out, but as long at they're all cut the same, it should be ok. I think I may have found a B&Q about 20 miles away that has a trend universal sub base in stock. Fingers crossed come 10am tomorrow morning!

big-all · Post by **big-all** » Sat Oct 10, 2015 8:02 pm

will the cutter fit through the bush center ??
thev radius will also be fractionally smaller

mattbowman81 · Post by **mattbowman81** » Sat Oct 10, 2015 8:04 pm

big-all wrote:will the cutter fit through the bush center ??
thev radius will also be fractionally smaller

Yes, it's only a 12.5mm cutter, so will just go through with enough clearance. Hopefully, I'll manage to get hold of a sub base, and perform the cuts as per the norm.

ayjay · Post by **ayjay** » Sat Oct 10, 2015 8:40 pm

I'm fairly sure it won't work, you need a 30mm guide bush.

It definitely doesn't work with a 16mm guide bush.

Timllfixit · Post by **Timllfixit** » Sat Oct 10, 2015 9:08 pm

Shame you can't find a cardboard tube of the right size to pop over the bush you have..................

big-all · Post by **big-all** » Sat Oct 10, 2015 9:32 pm

Timllfixit wrote:Shame you can't find a cardboard tube of the right size to pop over the bush you have..................

pollypipe

Job and Knock · Post by **Job and Knock** » Sun Oct 11, 2015 6:37 pm

I'm with Ayjay in saying it won't work. The relationship between the jig, the cutter (incidentally 12.7mm or 1/2in and not 12.5mm which would leave a gap in the corner) and the guide bush is absolutely critical, especially as the mason's mitre joint includes a curve. I've had to work this out in the past in CADCAM and changing the size of any element by even 0.5mm can reult in a "gappy" joint - even using a cheap slightly undersize guide bush can introduce a noticeable gap in the finished joint

Is a 25mm guide bush ok in my jig?

Is a 25mm guide bush ok in my jig?

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Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?

Re: Is a 25mm guide bush ok in my jig?