Safely cutting lap joins on table saw

[etyekmot]

Hi all,

New member here (I've been lurking for a while).

I'm an aspiring weekend warrior with a few small projects using mostly hand tools under my belt.

I've bought a DeWalt table saw and want to make a cart for it that I've drawn plans for, which is mostly just half laps and cross laps screwed together. My plan is to use the mitre gauge to cut them with a bunch of repeated passes and then to clean them up with a chisel (struggling to find a flat toothed blade).

Now, a lot of my "learning" so far has been from American wood workers, and I know there's plenty they do across the pond which would be considered bad practice over here in our complete-hand loving isles.

So I want to check whether this is considered safe - I've tried some cuts this way, and not experienced issues but don't want to fall in to bad habits.

Some posters I've seen state that it's considered bad practice but I couldn't find recommended alternatives. Just wanting to check if this is safe to do. The saw has the riving knife which moves up & down with the blade, so no need to remove it whatsoever for the non-through cuts.

Also, if there are any recommendations for British wood workers on YouTube or elsewhere, I'd love to hear some

Thanks
Tom

 

[TRITON]

A router is a far safer way to cut lap joins. and if the router has micro adjust, all the better

I'd saw down first with a handsaw(Much like when hand cutting tenons) to reduce the amount of waste the router take off and that will make it quicker.
Plus the small squares you get after are very handy as softeners when clamping up, especially with F clamps
Plus my own jigs i use a board that the piece to be cut lays on rather than one that sits on top of the component. but its all the same really

eg

 

[duke]

Oops deleted response

 

[Yojevol]

A homemade tablesaw sled would be a good addition to your kit at this stage and would be safer than the mitre gauge.
Brian

 

[duke]

A homemade tablesaw sled would be a good addition to your kit at this stage and would be safer than the mitre gauge.
Brian

Agree

 

[johnnyb]

Whilst the danger/ quality aspect of cutting tenons deserves some thought. Any method that uses 2 reference faces relies on the wood being the same thickness and not being bent. The squareness of the shouders relies on the reference faces being parallel as your cutting a single joint from 2 different references. Hence many methods can only be considered roughing out needing some finishing. Often with a router plane that adjusts the tenon cheeks and preserves its co planarity(is that even a word?) A shoulder plane is useful on the tenon shoulders and also the cheeks. But you do need to control the final outcome. If possible imagine what affects the squareness/flatness of the structure your making

 

[johnnyb]

Cutting tenons with a tenoner and mortices with a morticer replicates the hand method(partially) by using a single reference face to cut both edges.

 

[Orraloon]

There are quite a few ways to do it. Three here are an example and also show a tablesaw sled and a tenon jig.
3 Ways To Cut Half Lap Joints - YouTube
As you are new to woodwork it would be good practice for you to do at least a couple of them the hand tool way. Doing them on the tablesaw with a sled or the miter gauge is about as safe as anything else you would do on a tablesaw. Perhaps leave the tenon jig out for now until you get some more experience. I have never liked the idea of long bits of wood on end on a tablesaw. As Brian said a sled for the tablesaw would be a handy addition to your woodworking kit.
Regards
John

 

[Doug71]

I would suggest you do them with hand tools, if you have a mitre saw (that trenches) or a router they could be used to speed things up a bit.

Avoid doing anything on the table saw that involves removing the guard.

 

[niall Y]

I've relied on my radial arm saw, for many years. to do lap joints and tenons. Standing midway along one of the walls of my workshop, it is just so convenient to use at a moments notice. I appreciate that they are no longer in fashion. but using them for tenons or half-laps is just so easy.

I started out in business, using a table saw for this operation, which is perfectly adequate, done the right way. Though I have to confess that I wrecked the bearings on my first saw by cleaning the tenons up, by sliding them sideways across the top of the revolving saw blade. To be clear this is not good practice, either from the point of view of safety, or for ones saw.

I finally graduated to using a spindle spindle moulder , though if I'm just making a few joints I can seldom be bothered with setting it up, so I use the RAS.

 

[guineafowl21]

I've relied on my radial arm saw, for many years. to do lap joints and tenons. Standing midway along one of the walls of my workshop, it is just so convenient to use at a moments notice. I appreciate that they are no longer in fashion. but using them for tenons or half-laps is just so easy.

I started out in business, using a table saw for this operation, which is perfectly adequate, done the right way. Though I have to confess that I wrecked the bearings on my first saw by cleaning the tenons up, by sliding them sideways across the top of the revolving saw blade. To be clear this is not good practice, either from the point of view of safety, or for ones saw.

I finally graduated to using a spindle spindle moulder , though if I'm just making a few joints I can seldom be bothered with setting it up, so I use the RAS.

I do all my tenons and laps on the RAS too. Set up the first tenon to the marks, using a scrap of wood clamped to the fence as a length stop, then zing away through the others.

I do clean up the faces by sliding the wood sideways, but only after breaking off the waste slices with a hammer. It seems like only a very light sideways loading, and I keep my hands a good 12” from the blade, standing on the left of the machine.

For larger runs of tenons, this old Wadkin trenching set works very well (guard removed for clarity!):