PVC Dominos??

[roblg3]

I awaiting receipt of an XL.  I have a project to fab PVC fluted pilaster columns to replace some rotten ones.  I'd like to make the mitered corner alignment easy, i was thinking dominos for alignment.this is 3/8 versatec sheet cut and routed, i was playing with a lock miter bit, but got a little frustrated with the set up and i'll revisit that with thicker material.  I'll be bonding with pvc cement so i don't have a worry about strength as much as getting the corners dead on.  I'm hoping to impress this new client seeing that there's alot of work he needs.  any ideas for the alignment? or dominos to use?
thanks

 

[NiteWalkerGR]

You can use dominos dry for alignment. I'd not go crazy with size. 4 or 5mm tops.
That pvc stuff cuts and routs really easily.

 

[Brice Burrell]

I'm not sure you'll be able to get dominoes in mitered 3/8" material??  I'd just use packing tape.

 

[campbellcraft]

That's the difference between you and I, I'm from the Northside and I'd use duck tape and 16p nails. Of course another difference is you have talents I seem to be lacking.  [big grin]

 

[peter halle]

Whereas you are using the dominos for alignment - PVC dominos aren't going to have any real strength with their cellular construction I would suggest that you try to use wooden dominos instead if they will even work.  If they do you will have to place them so close to the rear of the boards that they won't be doing a lot for you.  The glue fusing the two pieces together will - if done correctly - be the sealant as well as providing the strength to the joint.

Peter

 

[roblg3]

i'm just looking for alignment.  the glue will "weld" and be very strong by itsself. it's just a long run and there isn;t much time to "play" with the pvc glue so i need alignment to be very much there already.  i really wish i wasn't so frustrated with the lock miter bit.  i guess i'll try to buy some set up guides or something.  thanks all

 

[NiteWalkerGR]

I missed the part about it being 3/8" thick material.

A rabbet miter joint would work.

 

[Stoli]

Check these out.

http://www.infinitytools.com/2-Pc-Lock-Miter-Master-Jig-Set-For-3_8-1-3_16-Stock/productinfo/00%2DLMM/

 

[Michael Kellough]

I missed the part where you said the columns would be square.

In that case you should revisit the lock miter bit, though I'm not sure how difficult it will be to get all the charged particles of PVC out of the grooves so the parts fit well...

You do need a smaller lock miter bit for 3/8" stock.

The gauges Stoli linked look very helpful and the description says they work with most brands of bits.

Without using such gauges adjust the height of the cutter so two edge trimmed pieces fit together flush (when one is inverted).
Then re-adjust the fence so the sharp miter edge just contacts the outfeed side of the fence. If the stock is of consistent thickness the parts should fit correctly.

I also don't know how much time you have to clamp the parts before the glue gets too stiff.

Make some clamping aids/edge protector strips by running some narrow scraps of 3/4" ply upright through the lock-miter setup.
The extra thickness will protect the sharp edge of the miter.

Fit one of those strips to the free side of the edge routed piece. You might be able to stand it up with the support of the strip
which will make adding glue much easier.

Then, when both sides of the joint are glued you can hammer it home with the protection of the scrap strip

 

[bigjonh]

Most of the prefab PVC column wraps  I've used have a v groove routed for a solid folded corner. My research for a project led me to believe that lock miters are difficult with a handheld router. In the end my supplier in DC had the columns made for me with lock miters, sent to the  job flat packed and we assembled and glued them

 

[Brice Burrell]

I posted earlier about using tape to align and clamp the miters.  If this was my project I wouldn't go with 3/8" material or miters unless I absolutely had to.  I'd use 3/4" (or 1/2" at a minimum) with butt joints.  I'd glue and screw (or pin) the joints, after the glue is dry I'd fill and sand perfectly flush.  Once you rout flutes in 3/8" you aren't going to have much material left.  I'm guessing the pilasters are something like 8-12" wide, that might be a bit flimsy unless it's well supported behind.  Also, expansion/contraction could crack the 3/8" in the thin parts near the areas where it's fastened.     

 

[monstrol]

Have you ever heard of raptor plastic nails? You need to buy a dedicated nailer but hypothetically you could glue and nail in an efficient manner. Just a thought.

 

[Max Neu]

Do you have a biscuit joiner, or access to one? If so, You could use the corian biscuits made by lamello.

 

[Toolpig]

Use the dominoes (or biscuits) for alignment and Bond-n-Fill for joining PVC to PVC...

http://www.bondfill.com/bond-and-fill-structural

I awaiting receipt of an XL.  I have a project to fab PVC fluted pilaster columns to replace some rotten ones.  I'd like to make the mitered corner alignment easy, i was thinking dominos for alignment.this is 3/8 versatec sheet cut and routed, i was playing with a lock miter bit, but got a little frustrated with the set up and i'll revisit that with thicker material.  I'll be bonding with pvc cement so i don't have a worry about strength as much as getting the corners dead on.  I'm hoping to impress this new client seeing that there's alot of work he needs.  any ideas for the alignment? or dominos to use?
thanks