Half lapped joints

[Barry Burgess]

I have 30 half lapped joints to make - which means cutting 60 joints - it would be easy using a stacked dado( watching Norn). Without one, how can I do these joints with the least amount of work
Thanks for the help
I have a table saw, bandsaw and a mitre saw plus circular saws.
Thanks in advance

 

[AndyG]

Can you not use the table saw, using some kind of cross cut carriage? Cut each extreme of the joint, then a few cuts between. You'll probably have to do a bit of cleaning with a chisel, but at least the width and depth of the joint will be clear.
With some stops on the carriage you could more easily repeat the cuts, so each joint is the same.
Andy

 

[OPJ]

You could also use the router table in a very similar fashion. If you're concerned about blunting the cutter, why not just buy a cheap one and throw it away after?

A sliding mitre saw with the 'trenching' facility is another option.
Or a radial arm saw, with the blade raised to half thickness of the timber.

Then, of course, there's the bandsaw. Set it up accuractely enough and you'll fly through the rip cuts. Trouble is, you may have to add a little care and attention when it comes to the final crosscut to create the shoulder.

It all depends on what you have access to really.

All the best, anyway.

 

[Philly]

Barry
How about a jig to hold the piece and for a router to run over the top. The jig controls the width of the dado and the router the depth (half the timber thickness).
Or come round my place for a dado-fest! :wink:
Cheers
Philly

 

[LyNx]

Is this for a torsion base?? I used my table saw with a crosscut sled.

What material are you using, did you opt for MDF


Andy

 

[Wanlock Dod]

I've regularly used the method that Andy suggests, and all I can say is that even I find it easy

I'm sure that there are quicker methods, but that one is certainly simple (although I've never done it for such a large batch of joints).

Cheers,

Dod

 

[Barry Burgess]

Barry
How about a jig to hold the piece and for a router to run over the top. The jig controls the width of the dado and the router the depth (half the timber thickness).
Or come round my place for a dado-fest! :wink:
Cheers
Philly

Philly I have a triton router and table so I could try that option but I was worried about tear out and was looking to clamp say 4 pieces together to ease the work load.
A table saw with a dado looks one of the easier options.

 

[Barry Burgess]

Can you not use the table saw, using some kind of cross cut carriage? Cut each extreme of the joint, then a few cuts between. You'll probably have to do a bit of cleaning with a chisel, but at least the width and depth of the joint will be clear.
With some stops on the carriage you could more easily repeat the cuts, so each joint is the same.
Andy

Andy to me the table saw would be slower but possibly better than the router but the saw blade is 3mm and the router bit could be up to 25mm and thats why I asked.

 

[Barry Burgess]

Is this for a torsion base?? I used my table saw with a crosscut sled.

What material are you using, did you opt for MDF


Andy

I am considering my optons at present - I am using 18mm ply in the current design and am making a frame out of 2X4. - but not finalised yet.

 

[Philly]

Barry
To speed up the router method you could remove majority of the waste with a hand saw and chisel. I know what you're thinking-that will take ages! :roll:
But it doesnt take long to make two saw cuts near the edge and then chisel out most of the waste. You could then clean up with the router in one pass, probably eliminating tearout as you will be removing so little material.
Or you will have to pop round and we'll get ther dado out :lol:
Hope this helps
Philly

 

[Anonymous]

Barry

As my saw won't take a dado cutter, I usually cut most of the waste on the bandsaw and then run it over the router table to remove the last mm or 2. Gives a quick and accurate joint.
Alternatively, if great accuracy is not paramount, I would run it against the fence on my bandsaw with a dure edge blade in

 

[AndyG]

After a little more thought, I'd probably go for the router method, this is probably biased because I've not actually got table saw!!
Can you hold all 30 pieces together with a couple of sash clamps joint face upwards (with a waste piece at each end). Then on top, clamp a couple of straightedges. It would then be a simple case of running the router between the straignt edges up and down the stack of timber.
The tear-out would be very minimal as each piece would support the previous and the waste pieces at each end would support the end pieces.
Setup time would be very low, cutting time wouldn't be too bad, especially if you'ce got a decent width router bit. Just cut down to the required depth in small steps.
Hope that all makes sense.
Andy

 

[Barry Burgess]

I was looking to clamp a number together and do the edge cut on the table saw and remove the rest on the router with a 25mm cutter in the table rather than from above.
Thanks to all for all the ideas - I am going to try a number before finalizing the bulk