Thread: Tufnoll {sp?} or Perspex for router table insert?

Dingo, from my reading on the subject LEXAN would be best. Perspex has a tendency to shatter under stress whereas Lexan retains its itegrity. I don't know about tufnol but one of the benefits of lexan is that it is clear and I believe tufnol is opaque /brown. I found it easy to mark holes etc in a clear material for fastening the router base and for the attachments into the table.

Shane

From your post it seems like you have pretty much made up your mind.

Most commercial inserts are non see through, like alli or black plastic. It is not imperative to see your router while you are routing!

Half inch of anything is really overkill and you'll have to rout it thinner otherwise you'll loose too much of the cutter height. Perspex is fairly brittle, especially if routed to 6 mm and drilled. Tufnol is tuff, but a lot of effort to get the area where the router is mounted down to about 6 mm. Sort of defeats the object of using half inch. Try and get 6 mm Lexan ( expensive ) or 4, 5 or 6 mm alli...as cheap as chips and it works for 99% of router tables. Make the table top a tilt up top and that will solve the problems. There are marathon threads on here about router tables, just do a search.

Shane, unsure about exact composition of "tufnol" but a quick google and educated guess seems to flag it as phenolic, a strong engineering plastic. Of the two, I'd be more inclined to use this, you primarily want the plate to be rigid & strong, where the phenolic excels.

Having said this, I made my router table with a phenolic insert about 2 years ago, and am about to make a steel insert (about 3mm or so), the only reason being depth of plunge that you lose by using the 1/2" plastic. Wasn't a factor with most bits but have one with a shank mounted bearing, and the loss of plunge depth is an issue here.

Aluminium would be good too with the advantage of being easier to machine.

Perspex (or acrylic, the actual material) would need to be at least 1/2" thick to get the rigidity and strength you need. Lexan (polycarbonate) is less brittle than acrylic but isn't quite as rigid and 6mm would be way too thin IMO, 1/2" would be min. thickness again.


HTH........cheers.........Sean

Hi,

Unless you are making a drop-in plate complete with router attached, a piece of 5-6mm perspex is more than strong enough to use. Especially when its screwed in four places to the router base and sit in a rebate in the table.
My table insert is only 180mm square.

Beware of using aluminium plate (and probably steel) if they have been cut in a guillo. Thicker sections tend to get a slight 'bow' due to the guillo blade stretching the metal as its cut. Its only slight, but be aware it may not be perfectly flat.

If you use the phenolic sheet use a good quality respirator, the dust is REAL BAD.

Good Luck.

Glen.

When I worked at hawker de Havilland we used Tufnol inserts in the manufacture of carbon fibre components. They would be inserted in the honeycomb core of landing gear doors where you wanted bolts etc to fasten the component to the aircraft. I remember the stuff being very heavy, dense and waaaaaaay strong. Injured myself several times thumping them into place

Hey Dingo, I have used 6mm Perspex for my router insert with the router attached to the perspex and I do have a drama with it flexing slightly when routing the edges of my work. I will be tying a smaller peice of perpex in the neare future to hopefully get rid of this problem.

hope this sheds a bit of light on the matter

PS happy mining

Heh groovers, on my desk I have a laminated piece of acrylic- polycarb- acrylic (12mm-25mm-12mm) inserted in this lamination is a 30-06 projectile (100m) & 44 mag projectile (25m). So I think 12mm polycarb is sufficient for a router insert.

"Tufnol" is a trade name for SRBF (Synthetic Resin Bonded Fibre) (cotton) it comes in various grades of fabric weave and density.
Very tough, should be fine for insert plate, have used it extensively over the years in Aircraft and Radar research environments.
Some router manufactures "Trend" for one use it for base plates.
Ideal for long life templates, expensive!

WWW.trendmachinery.co.uk

You may also see "Paxolin" (? spell) as a trade name, this is SRBP (synthetic resin bonded paper).
tough and rigid. more likely to shatter round the edges if dropped, than tufnol.