Machining profiled plinth block
6/29/15
We need to provide several plinth blocks matching the one in the photo, for a fire restoration job. We have a W& H molder. Getting a knife ground is no problem, but I'm almost certain we will have substantial tear-out. How are these 'normally' machined? How would you do it? Thanks.
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6/29/15 #2: Machining profiled plinth block ...
I would just do that on a shaper. Make a quick carrier jig. They also make shaper heads that accept W&H knives.
6/29/15 #3: Machining profiled plinth block ...
We have a couple of corrugated heads we can have knives ground for. Thought of the shaper, but was a little leery of projectiles. I'm sure we can come up with a way to hold the stock and feed with light passes.
Thanks,
6/29/15 #4: Machining profiled plinth block ...
Clamp all your blanks together to run the two edge profiles on a shaper then run face cuts.
6/29/15 #5: Machining profiled plinth block ...
I wondered about that. Will the shaper want to pull the ones in the middle out? Can one get enough clamp pressure? Or leave them long and run some kind of rod or pc down the middle to keep that from happening? Some where in my subconscious I this recollection of this happening.
6/29/15 #6: Machining profiled plinth block ...
I like to use high quality double sided masking tape. stick them together.
6/29/15 #7: Machining profiled plinth block ...
Bob,
When I first saw your post this morning, I immediately thought of this, but it took me a while to find it.
Watch 0:40-1:40
Mark
Henige's Custom Woodworking
6/30/15 #8: Machining profiled plinth block ...
We would also do these on the shaper. Clamp up a stack and run the edges, Like in the video posted the cutout in the fence is important to reduce tearout. It is made by pivoting the fence assembly into the running cutter, one end secured. I recommend putting travel limiting spacer blocks on the table to prevent it from getting away from you. Those same blocks can be left inplace so you can advance the process in smaller steps. Requires a heavy shaper. We've got a profile grinder but you can also grind a set of corrugated knives by hand. Balance the knives before use.
6/30/15 #9: Machining profiled plinth block ...
All of this is very helpful. I think we can handle it. Thanks for your time and expertise.