Making hardwood DG sashes - Advice on how to cut rebates

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

RichD1

Established Member
Joined
18 Nov 2013
Messages
111
Reaction score
5
Location
Weymouth
I'm replacing the sashes on my bay window with hardwood (sapele) ones to take DGU's. I've sawn and thicknesses the stock material down to size and now need to rebate them all to take the DG.

The sticks are 53mm x 43mm Qty 13 and 92mm x 43mm Qty 4. The rebates need to be 34mm x 12mm and the sticks are about 950mm long.

I have a router table and a table saw but can't decide which is the better machine to use taking into account the number of sticks I have to machine.

The table saw would be much quicker but a tad more risky and I would need to make some holding jigs. The table saw does have a side sliding table which would be less risky but probably more difficult to set up and hold due to the length of the sticks.

I do have various rebate cutters on 1/2" shanks or is there a better cutter to use like a slotting cutter to replicate what the saw blade would do?

Richard
 
Last edited:
I would use the router table, mark all the workpieces clearly and take light cuts, running all pieces through before increasing depth and repeat. Also need to move fence unless you can go wider, 38mm Standard Series

These will give 21mm in a pass Small Series so two passes to get your 34mm. They leave a nice finish and cut well.
 
You will need jigs / pressure bars for which ever method you go for. For me, the thought of passing by hand material through a router table is a good way to an appointment with a hand surgeon.
Of the two methods, for me the quickest, best and simplistic solution would be to run them through the table saw. Depending on the rebate size you can often get the beading from the waste you’ve cut out.
 
Yes table saw - really easy as long as you have proper rock-solid set-up with hold-in feathers on in and out tables, and hold-down feathers on fence. And of course, use two push sticks.
No need to buy daft gadget feathers they are very easy to make (search this forum) and do a few trial runs with some offcuts.
PS and watch out for the waste being flung out like an arrow, but it won't do much damage!
Might need to clamp or prop the end of the fence to stop it wandering off e.g. a G clamp and a lath
 
You will need jigs / pressure bars for which ever method you go for. For me, the thought of passing by hand material through a router table is a good way to an appointment with a hand surgeon.

I already have feather boards for the router table.

Might need to clamp or prop the end of the fence to stop it wandering off e.g. a G clamp and a lath

Do you mean clamping the far end of the main fence?

How would you pass the 2nd cut through? With the waste piece against the fence or on the other side of the blade?

Richard
 
I already have feather boards for the router table.



Do you mean clamping the far end of the main fence?

How would you pass the 2nd cut through? With the waste piece against the fence or on the other side of the blade?

Richard
Waste against the fence. It can get slung out - not desirable but generally not a prob.
This way around any wobbly mistake will be a cut into the waste, the other way you'd cut into the workpiece
Or you can add a spacer to the fence above the highest part of the rebate, so leaving a safe drop-out space for the waste with no risk of it being picked up and shot out.
Apologies for crude sketch - just trying out back of envelope and the computers own camera! Quite handy, must do this more often!

Yes - clamp far end of fence - or clamping a bit of scrap against it so it won't get pushed out of line

safespace.jpg
 
Last edited:
This sounds like a fairly painful way to do it but If I remember rightly cmt used to do a router bit that would do the mould and rebate, like a spindle moulder would. I have one somewhere.

If using what you have I would do a rough cut on the table saw, then just take of 1mm on the router to clean it up nicely.

This is why I bought a spindle moulder, try it you won't regret it.

Ollie
 
This sounds like a fairly painful way to do it but If I remember rightly cmt used to do a router bit that would do the mould and rebate, like a spindle moulder would. I have one somewhere.

If using what you have I would do a rough cut on the table saw, then just take of 1mm on the router to clean it up nicely.

This is why I bought a spindle moulder, try it you won't regret it.

Ollie
Not painful at all - really quick and easy, if set up carefully. But yes spindle much better, perfect cut in one pass every time.
 
The table saw method requires the crown guard to be removed from the saw which is perhaps not great advice for someone who isn't that experienced with woodworking machinery. If you're using a piece of kit and have to start removing safety features, then you might be using the wrong piece of kit.

Spindle moulder is the answer from a production workshop point of view, but I see no reason why the same results couldn't be achieved on a decent router table. The main issue is stabilising the work piece on the outfeed section of the fence.


1613872428973.png
 
The table saw method requires the crown guard to be removed from the saw which is perhaps not great advice for someone who isn't that experienced with woodworking machinery. If you're using a piece of kit and have to start removing safety features, then you might be using the wrong piece of kit.
.......
Yes I but if he hasn't got a spindle moulder then that isn't an option in the first place.
However he is looking at the TS as an option.
We never know what our man will decide to do, nor how competent or risk averse he is, so you just have to point out the hazards and the additional safety measures, which I did - feather boards, 2 push sticks, safe space for waste fall out, secure the end of the fence.
Better that than have him fiddling about and losing a finger.
Re the false fence and safe space - this becomes essential if you are tilting the saw blade and cutting a bevel. Otherwise the triangular waste piece can get lifted by the blade and wedged in tight between blade and fence - most likely to be shot out forcefully at the rim speed of the blade. I discovered this early on and the off-cut penetrated the plaster board of the wall opposite, about 6 ft away.
 
Last edited:
..... The main issue is stabilising the work piece on the outfeed section of the fence......
No prob if the workpiece has a large enough flat face left to be pressed against the outfeed - by powerfeed or featherboards carefully placed. In fact your outfeed add-on fence could be problematic in that any wobble in the cut, or chipping getting in between, could force the workpiece out - a blip to be followed by the cutter so it wouldn't go back in, thereby magnifying the error.
It's supported by the in feed table all the way anyway, until the last inch or so goes past the end of it
 
Last edited:
Better that than have him fiddling about and losing a finger.

I am totally risk adverse as I recently lost the top 8mm off my index finger on the left hand whilst using my bandsaw. I was rough size the sticks ready for thicknessing. The height of the workpiece was 100mm so quite a lot of blade exposed. I think it was complacency as it was on the last cut of 20 odd sticks. Strange, never felt a thing until I noticed the workpiece was covered in blood!!!! I consider myself very lucky that it wasn't more of the finger.

At the moment I'm favouring the router option but need to find something to support the wood on the outfeed side. I do have several fingerboards so this may be enough Just measured the table and it has about 40cm on both sides of the cutter.

Richard
 
Waste against the fence. It can get slung out - not desirable but generally not a prob.
This way around any wobbly mistake will be a cut into the waste, the other way you'd cut into the workpiece
Or you can add a spacer to the fence above the highest part of the rebate, so leaving a safe drop-out space for the waste with no risk of it being picked up and shot out.
Apologies for crude sketch - just trying out back of envelope and the computers own camera! Quite handy, must do this more often!

Yes - clamp far end of fence - or clamping a bit of scrap against it so it won't get pushed out of line

View attachment 104072


If I had a lot to do it would be pretty much as Jacob does except being a barbarian I would use a dado blade. Then there is no leftovers to kick back since it is all turned into sawdust. I would however add a "shelf" to his Packing Piece that would cover the top of the blade by several inches out and front and back to keep the hands out of the blade area between cuts. The Packing Piece can then be solid to the table with the dado blade raised up into it. Full contact of the work against the fence until after the blade.

Posted to show a different take of the same problem, not necessarily advocating its use by the OP.

I don't like router tables for this kind of cut unless doing non thru cuts.

Pete
 
I am totally risk adverse as I recently lost the top 8mm off my index finger on the left hand whilst using my bandsaw. I was rough size the sticks ready for thicknessing. The height of the workpiece was 100mm so quite a lot of blade exposed. I think it was complacency as it was on the last cut of 20 odd sticks. Strange, never felt a thing until I noticed the workpiece was covered in blood!!!! I consider myself very lucky that it wasn't more of the finger.

At the moment I'm favouring the router option but need to find something to support the wood on the outfeed side. I do have several fingerboards so this may be enough Just measured the table and it has about 40cm on both sides of the cutter.

Richard
It's repetitive work where slips are most likely to happen and safe procedures most need setting up.
2 push sticks being the simplest - if you get it wrong you just lose a bit of push stick. If you get into the habit your fingers are never nearer than 6 inches or so to a moving blade or cutter and the chance of accident is vanishingly small.
The standard push stick is cleverer than it looks - you can very the pressure from the mouth to the tip, or to both, with a lot of control. Make copies from mdf or ply - they are consumables, your fingers are not!

pushstick.jpg


PS and they are not called "sticks" they are stiles, rails, glazing bars, pulley stiles, linings, staff beads....etc etc
 
Last edited:
Blimey Richard! You think the saw is risky?? Last week you were going to tenon and mould everything on a spindle moulder even though you had zero experience with using one?? :LOL:
 
Hi

Now I can see what you are looking to achieve, you have the same issue with using a table saw or the router. It is something that took me a while to get to grips with but think I now have got it. You need to look at what comes out of the router cutter, is there sufficient material to support the workpiece following the cut.

This comes down to forward planing, think how you are going to perform the task before just going for it, something I did not do and would end up with the last section of profile a mess because as it left the cutter there was nothing supporting it, now I apply forward planing. In your task you have a few options.

1) Make several support pieces that you can use double sided tape to hold to the fence just past the cutter, set cutter height to the support piece and make your first passes on all the workpieces.

2) Change the support piece for the next one, and raise the cutter to the new height and again make your passes on all the workpieces.

3) Continue until at final size

Another method I have used is to remove all the material except leaving an edge of material to act as the support. Last task is then to just remove this remaining edge.
 
......... I recently lost the top 8mm off my index finger on the left hand whilst using my bandsaw. ......
Hi

Now I can see what you are looking to achieve, you have the same issue with using a table saw or the router. It is something that took me a while to get to grips with but think I now have got it. You need to look at what comes out of the router cutter, is there sufficient material to support the workpiece following the cut.

This comes down to forward planing, think how you are going to perform the task before just going for it, something I did not do and would end up with the last section of profile a mess because as it left the cutter there was nothing supporting it, now I apply forward planing. In your task you have a few options.

1) Make several support pieces that you can use double sided tape to hold to the fence just past the cutter, set cutter height to the support piece and make your first passes on all the workpieces.

2) Change the support piece for the next one, and raise the cutter to the new height and again make your passes on all the workpieces.

3) Continue until at final size

Another method I have used is to remove all the material except leaving an edge of material to act as the support. Last task is then to just remove this remaining edge.
You don't need support pieces of any sort as long as there is enough flat face left on the workpiece to keep it straight against the out-feed fence.
In fact "support pieces" can screw up the job - if there's any error or wobble then the support piece picks this up and replicates it along the whole length
If not enough flat then you last suggestion would work better.
 
If you go with the router table this is the kind of thing people mean by a support piece attached to the fence, it fills the rebate so the timber doesn't "wobble".

shaw guard 2.jpg
 
If you go with the router table this is the kind of thing people mean by a support piece attached to the fence, it fills the rebate so the timber doesn't "wobble".

View attachment 104272
But it won't wobble until the last few mm go past the in-feed fence and it won't wobble then either if the feather-board, shaw-guard whatever, bears firmly on the flat part of the moulding
But if it does wobble at all for whatever reason your support piece will pick up on the wobble and set the remaining length off line too. Bin there dunnit!
 
Back
Top