Cutting/routing/finishing HIMACS Acrylic

[Deadeye]

I'm meandering towards mounting a router in my saw table and have been given a largish offcut of HIMACS 20mm acrylic that will fit nicely.
This website HIMACS | LX Hausys UK says it can be worked as wood, but Lathams HIMACS | Solid Surface Material | Commercial | Residential | Latham Timber say some specialised techniques needed.
Do I just stick it on my table saw and cut the end off? Will it pipper my blade (60% mineral is a worry)? Routing a T track? Sanding the edges?

 

[Distinterior]

Considering what you are planning on using the offcut for, there would be no specialised techniques needed.

Ideally, a negative rake saw tooth blade would be best to cut it with, but you would get away with a decent fine tooth blade.
If it were me, I would cut it on the saw about 1 or 2 overlength and take it down to final dimension by means of a router as you will get a far superior finish this way.

Drilling holes in this type of material is, fairly straightforward. Again, you will get a cleaner, crisper finish on your cutouts & holes if you use Tungsten tipped tools.

Normal sanding & machining practices will suffice but dust extraction really is a necessity .....

 

[Deadeye]

Considering what you are planning on using the offcut for, there would be no specialised techniques needed.

Ideally, a negative rake saw tooth blade would be best to cut it with, but you would get away with a decent fine tooth blade.
If it were me, I would cut it on the saw about 1 or 2 overlength and take it down to final dimension by means of a router as you will get a far superior finish this way.

Drilling holes in this type of material is, fairly straightforward. Again, you will get a cleaner, crisper finish on your cutouts & holes if you use Tungsten tipped tools.

Normal sanding & machining practices will suffice but dust extraction really is a necessity .....

Many thanks. I need to attach some bolts. Can I just drill and tap?

 

[Distinterior]

...... I need to attach some bolts. Can I just drill and tap?

You could, but the belt & braces approach would be to fix threaded inserts into the Himacs and screw the bolts into them.....Especially, if you are planning on using those bolts to hang the router from.

 

[Deadeye]

You could, but the belt & braces approach would be to fix threaded inserts into the Himacs and screw the bolts into them.....Especially, if you are planning on using those bolts to hang the router from.

I can do that for the insert...but I need them in the end edges to fix to the table saw rails. It's 20mm thick and I was planning on using M8 or M10 bolts

 

[Distinterior]

I can do that for the insert...but I need them in the end edges to fix to the table saw rails. It's 20mm thick and I was planning on using M8 or M10 bolts

M8 or M10 tapped directly into the end thickness of a 20mm section of solid surface material?.....I think you will be setting yourself up for disappointment.....It may be okay initially, but I think over a relatively short period of time, you will get stress cracking in the area of those bolts.

Edit.
I would suggest you try and find a way of gluing a non expanding threaded insert into the " end grain".

 

[ChaiLatte]

I would suggest you try and find a way of gluing a non expanding threaded insert into the " end grain".

Another option might be a barrel nut, beloved of Ikea beds everywhere.

It is possible to buy or modify them so the thread is not in the centre of the barrel, meaning it is possible to insert them into a blind hole if the top of the sheet needs to be unblemished.

Even M8 seems overkill for this. Colin Chapman was noted for saying that you could suspend a London bus from a 1/4" bolt.

Edit:

Please look at (and maybe price) commercial solutions as they might provide some inspiration for a home-brew alternative.

https://www.theinsertcompany.com/self_anchoring_inserts.phphttp://www.npfasteners.com/composites/keep-nut.htmhttps://squirrels-uk.com/

 

[MikeJhn]

All of the holes in this overhead guard where self tapped into the edge, none have cracked or failed in quite a few years of use, M4 into 10mm mostly.

 

[Distinterior]

@MikeJhn With all due respect, a few small self tappers into the edge of what I assume is a Perspex type material, is not the same as threading bolts into the end of Solid Surface material.
The weight of the material itself is substantial, then add to that the weight of a decent router hanging in the middle of the panel, then add downward pressure of the material being pushed past the router cutter.

Obviously, I dont know the exact setup that @Deadeye was planning on,or how many fixings he was planning on using to fix the Solid Surface to his front & rear saw rails but with my experience of this type of material, I would advise not to just drill and tap a thread directly into the end of 20mm material.

 

[MikeJhn]

They are not self tapper, but bolts, if you look at the end of the Kantilever (only got a K on my Keyboard) the bolts are through the perspex to the other side and bolted.

 

[Distinterior]

They are not self tapper, but bolts, if you look at the end of the Kantilever (only got a K on my Keyboard) the bolts are through the perspex to the other side and bolted.

Sorry Mike, I read " self tapped" as meaning self tapper screws.

Even so, the stress on your blade guard is nothing like the stress that would be placed upon the solid surface panel that the OP is planning on using.

 

[ChaiLatte]

Even so, the stress on your blade guard is nothing like the stress that would be placed upon the solid surface panel

The other issue to consider is the frequency of use of the thread. The blade guard has been assembled and would stay assembled for the rest of its life.

On the router contraption, some of the bolts will be removed and inserted on a reasonably regular timescale.

What might work is to drill and tap the thread, then screw in a piece of threaded rod smeared with JB Weld. However, the piece then resembles a hedgehog. Hence, the suggestion above of female glue-in anchors is good for both engineering and ergonomic reasons.

 

[Sideways]

I would be minded to buy some heavy L section aluminium to attach to the saw sideways then the composite can sit on the flanges and be packed from below to level it. Look on ebay. It is readily available in many gauges (say 5mm) and dimensions (say 50mm x20 or 30mm). Affordable esp. if you got the worktop free or cheap.

I note that the stuff you have is a mineral loaded thermoplastic, so wear resistance against timber sliding across it could be good, but I would be wary of sagging over time and personally would add a couple of stiffeners below.
I bought an offcut of trespa high pressure laminate 30mm thick thinking it would be handy for an improvised table and found it to be slightly bent. If 30mm trespa can bend, 20mm thermoplastic surely can.

 

[Distinterior]

I would be minded to buy some heavy L section aluminium to attach to the saw sideways then the composite can sit on the flanges and be packed from below to level it. Look on ebay. It is readily available in many gauges (say 5mm) and dimensions (say 50mm x20 or 30mm). Affordable esp. if you got the worktop free or cheap.

I note that the stuff you have is a mineral loaded thermoplastic, so wear resistance against timber sliding across it could be good, but I would be wary of sagging over time and personally would add a couple of stiffeners below.
I bought an offcut of trespa high pressure laminate 30mm thick thinking it would be handy for an improvised table and found it to be slightly bent. If 30mm trespa can bend, 20mm thermoplastic surely can.

As you say Sideways, even at 20mm thickness, it will need some additional support / bracing underneath to prevent sagging.

 

[Deadeye]

I would be minded to buy some heavy L section aluminium to attach to the saw sideways then the composite can sit on the flanges and be packed from below to level it. Look on ebay. It is readily available in many gauges (say 5mm) and dimensions (say 50mm x20 or 30mm). Affordable esp. if you got the worktop free or cheap.

I note that the stuff you have is a mineral loaded thermoplastic, so wear resistance against timber sliding across it could be good, but I would be wary of sagging over time and personally would add a couple of stiffeners below.
I bought an offcut of trespa high pressure laminate 30mm thick thinking it would be handy for an improvised table and found it to be slightly bent. If 30mm trespa can bend, 20mm thermoplastic surely can.

Thanks. I think I will go this way, not least because of the fine adjustment it will afford

 

[Sideways]

I think @Disinterior summed up exactly how I would approach the machining. Aim to finish with tct cutters on the router, no need for sanding.
TCT saw blade will work. I might spring for a plastic / aluminium cutting blade for the tracksaw to cut it rather than dull a nice freshly sharpened woodcutting blade, but I would get further value from a blade like that for cutting aluminium and other plastic sheet material on the tracksaw.
Personally, I would probably use M6 machine screws to hold everything down. 5mm drill and m6 tap to cut a thread in the composite. As long as you aren't using the thread a lot, I think it will last a fair while and the holes will be small enough that you just drill them out and fit the brass inserts if the threads ever wear out.
I like stainless machine screws with countersunk torx heads for special little jobs like this. Very neat, never rust, and the torx gives a super positive engagement with minimal risk of rounding off like a hex socket for allen key.
Buy 10,20,50 off from people like boltbase on ebay.

 

[Fergie 307]

You could, but the belt & braces approach would be to fix threaded inserts into the Himacs and screw the bolts into them.....Especially, if you are planning on using those bolts to hang the router from.

Another way that might work would be to helicoil the holes. That way the thread is actually metal, but without having to secure an insert. Used to be a common practice in racing motorcycles etc to helicoil all holes in aluminium castings that would be taken apart regularly, to avoid the threads wearing out.

 

[Distinterior]

Another way that might work would be to helicoil the holes. That way the thread is actually metal, but without having to secure an insert. Used to be a common practice in racing motorcycles etc to helicoil all holes in aluminium castings that would be taken apart regularly, to avoid the threads wearing out.

Depending on how the OP's choice of router is mounted, a lot of the Dewalt, Elu & Festool routers I own have 6mm holes/ threads already tapped into the base of them, so it would just be a case of working out the PCD of the holes and then drilling corresponding countersunk clearance holes in the Himacs and you could fix the router from above rather than trying to tap or fit an insert into the material itself....? All depends on your choice of router of course!