Dovetail Router bit

[Coldcut]

I have just bought a dovetail jig(1/2") and need a 1/2" bit with a bearing so it dosen't foul the fingers.
I have a 1/2" diameter bit which has a 1/4"shank but no bearing,so no good,is it possible to buy a cutter and remove the bearing,as toolstation have got bits with bearings from as little as £3.24.
If its not possible i will have to buy one which will cost £12.20

 

[marcros]

do you definitely need a cutter with a bearing? on the ones that I have seen you usually use a guide bush on the router. That may not be the case for all jigs though. The dovetail cutter angle is usually critical too.

What make and model is it?

 

[MikeJhn]

As marcros has pointed out, most dovetail jigs use a guide bush not bearings, if this is the case with your purchase I suggest you get the Leigh e-Bush, its adjustable to get a tighter or looser fit of the joint which is very useful when refining your joints.

Mike

EDIT: to add link: https://www.leighjigs.com/ugs.php, it does not show it on that page, but the leigh bush is elliptical when turned in one direction or the other it tightens or loosens the joint.

 

[Coldcut]

do you definitely need a cutter with a bearing? on the ones that I have seen you usually use a guide bush on the router. That may not be the case for all jigs though. The dovetail cutter angle is usually critical too.

What make and model is it?

lumberjack dtj300 jig
My router guide bush is 30mm as in pic so no good as the router bit will hit the fingers.

 

[MikeJhn]

Your 30mm bush is not suitable for use in a jig. With a bearing on a dovetail router bit you are restricting your depth of joint to the thickness of the jig, this would in turn restrict the thickness of the timber you can joint, using a bush allows more or less depth to be used on the bit to allow a greater use of different thickness's of timber.

No diss-respect meant, but I think you need to read up on how a dovetail jig is used, the basics are shown in chapter one of the Leigh Jig document and the bush use on page 9: https://www.leighjigs.com/data/%20D4R%2 ... er%207.pdf

Use this link to go to the Leigh web site and download the D4R manual: https://www.leighjigs.com/support.php#rs27 you will not regret it, without fear of contradiction the Leigh jigs and manuals are the best out there, even if you don't buy a Leigh jig, the manual will give you a much better understanding of how dovetail jigs are used.

Mike

 

[Seiken]

MikeJhn, Sorry to contradict but on this type of jig you dont have the luxury of setting the depth of the cutter much. You set it to 15-16mm from router base to end of cutter (this may vary depending on the comb thickness but most chinese jigs seem to be the same), you then adjust this to tighten or looosen the joint.
Again most of these jigs use a 7/16" (12mm) bush although the instructions for the lumberjack jig say it comes with a bearing guided cutter.
I have a screwfix jig of this type and have looked at the instructions of a number of suppliers on the web and they are all pretty well identical.
The instructions for the Screwfix jig are on their website which may be of help. You cannot expect much variation to be available on a jig that costs less than £50 compared to a leigh at over £300.
PS As I said I've got the Screwfix jig and used it to make drawer boxes for two kitchens plus sundry other boxes.

 

[Coldcut]

MikeJhn, Sorry to contradict but on this type of jig you dont have the luxury of setting the depth of the cutter much. You set it to 15-16mm from router base to end of cutter (this may vary depending on the comb thickness but most chinese jigs seem to be the same), you then adjust this to tighten or looosen the joint.
Again most of these jigs use a 7/16" (12mm) bush although the instructions for the lumberjack jig say it comes with a bearing guided cutter.
I have a screwfix jig of this type and have looked at the instructions of a number of suppliers on the web and they are all pretty well identical.
The instructions for the Screwfix jig are on their website which may be of help. You cannot expect much variation to be available on a jig that costs less than £50 compared to a leigh at over £300.
PS As I said I've got the Screwfix jig and used it to make drawer boxes for two kitchens plus sundry other boxes.

Your right,
screwfix jig
lumberjack lumberjack dtj300
SIP doveatil jig
Axminster
They are all the same,just different names
All i need to buy is this https://www.trenddirectuk.com/c162x...MIv4_W0PXy1gIVjr3tCh2QgAMfEAQYASABEgLCvvD_BwE

 

[MikeJhn]

MikeJhn, Sorry to contradict but on this type of jig you dont have the luxury of setting the depth of the cutter much. You set it to 15-16mm from router base to end of cutter (this may vary depending on the comb thickness but most chinese jigs seem to be the same), you then adjust this to tighten or looosen the joint.

That's not a contradiction its agreement with what I said, you have a restricted depth of cut with a bearing guided cutter by having to keep the bearing inside the comb.

Mike

 

[Seiken]

As I see it it not just having to keep the bearing within the comb as most use a bush but the actual design of the jig that gives the jig its limits. The leigh jig is more versatile by design.

 

[Eric The Viking]

To answer the bearing question, you can get 1/4" bearings (for the shank of 1/4" cutters) in a range of sizes, but don't forget that the depth of cut directly affects "goodness" of fit, as Selken said.

I've got the SIP jig, and it's pretty nasty, so I bought into the Stots system secondhand (Rutlands sold a knock-off version for a while - don't know if they still do). I think it needs Leigh-spec cutters, which is slightly irritating as they are stupidly expensive. That said (and I've yet to use it) it seems a lot simpler and more flexible in use than the Clamping-frame ones. If you haven't committed,see if Rutlands still have them (can't believe I typed that!). The original Stots seems better, but I think he's moved on to making dovetails in a better place, sadly, and I certainly can't find a supplier of the original now (would love to be corrected on this).

I think both the Stots and the Rutland ones let you make secondary, disposable templates, so if you mess up the jig, it doesn't matter much. And there's no guide bushes necessary.

[edit]It looks like Milescraft in the USA bought the IP, as it used to be available from them. Their web site seems to show out of stock, but it's not clear if that means "discontinued" or just "we've currently run out." Price looks pretty good, too (frustratingly). The reviews are as recent as 2016 though, so there may be hope. It is really good, and I think it's simple to use (or seems so).[/]

 

[Raymond UK]

I bought some guided bearing dovetail cutters from China a while back. They were only about £3 each.

I used to use the SIP cutters but the bearings collapse very quickly especially on their own jig with aluminium comb. The Chinese ones seem a lot better and cheaper.

Also have one router setup with a guide bush and standard dovetail cutter but prefer the bearing cutter as the guide bush restricts the view of the workpiece.

I'll try and find a link for those cutters later.

 

[Raymond UK]

https://www.aliexpress.com/item/1-4x1-2 ... lsrc=aw.ds