I am looking for advice regarding cutting out an elliptical shaped piece of 3/4″ MDO using as my final step a flush trim bit, router and router table. Do people find it works best to use bit with bearing on top and have the template on the top or template on bottom of the MDO with bearing on the bottom of the bit? Any recoomendations on substrate that makes a good template? Any advice appreciated. Kieran
PS: Still waiting to hear on best filler to use on nail holes in exterior trim and clapboards.
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I like the table method with a bottom bearing ( shank) so that I can secure the work to the template with DeStaCo clamps and see the cutter ( and my fingers) as it works.
Leave "ears" for mounting the clamps or registration blocks on the template in an area that is "lead in" or "run out" of the cut so the bearing is engaged before actually cutting stock.
Alternatively you can brad nail or pin nail the template in an area that will later be trimmed away or covered.
MDF makes good , seldom used templates, but really, any void-less material , PVC trim, TREX, etc. will do.
Glazing putty, water putty, or ext. spackle are all used for nail hole filling..I use ext.spackle often.
Spheramid Enterprises Architectural Woodworks
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"If Brains was lard, you couldn't grease much of a pan"
Jed Clampitt
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Thanks for the quick response. I am working on some clapboards that have gaps btween the butt joints. Do you think the glazing putty would be a good filler for these areas?Kieran
Edited 7/22/2009 12:53 pm ET by ktkamm
No. You want Big Stretch caulk for that. It stays flexible and is quicker to get paint on.
Everyone has a "go to" caulk, some like Polyurethanes, some Painters type DAP Alex or Top Gun, and some like the fortified Vulkums and such, so you can expect others to disagree with me and each other.
I have found Big Stretch, Geocel, Lexel and PL Premium Polyurethane adhesive to be the mainly used in my work, and carry all in the van for just about any occaision.
In the shop I keep Phenoseal in addition to the other forementioned, I almost NEVER use any silicone product, except for some I got from a buddy that is used on the cooling towers in Nuke plants, but its crazy bad stuff.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
"If Brains was lard, you couldn't grease much of a pan"Jed Clampitt
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highjack.....
Sphere,
What exactly is Lexel, I've been using it for a couple years now and I always thought it was some kind of souped-up silicone. Good stuff.
Ditto on the Big Stretch also, but I only discovered it last year.
dug
It's not a silicone, because you can go over silicone and paint what was impossible. Silicone won't do that.
I don't know the exact make up, like Geocel being a TRI-Polymer, but as an adhesive and caulk, Lexel behaves similar, albeit it cures a bit harder than Geo.
I'll dig up a tube and look if it says, but often it's propriatary.
BTW , IIRC BigS. is made by the same co. as Lexel, Sashco.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
"If Brains was lard, you couldn't grease much of a pan"Jed Clampitt
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I like Lexel as well. It is much more clear than silicone and it is paintable. A PDF on Lexel is attached.Chuck Slive, work, build, ...better with wood
It's pretty tough to cut 3/4" MDO in one full depth pass. A plunge router with a template guide, rather than a bearing flush bit would be my choice. In this case, the template would go on top. You either need a template that is thick enough for the template guide or a short template guide. I've cut some template guides down for 1/4" template material. MDF 1/4" ply, etc. is fine if the template guide fits and you don't have hundreds to do.
Exterior wood shrinks and swells to some extent, filler doesn't. If you are filling a crack in Southern yellow pine, which moves a lot, expect some filler to crack or fall out. There are plenty of good fillers for nail holes. I don't like wood dough types or water putty. Famowood, bondo and other solvent type fillers are tough but you have to take a dip and get the lid right back on or they will dry up in minutes. Bondo types have to be mixed and you have limited time to get them in place. Something like Zar woodpatch is latex. Sands easy, good for vertical surfaces but not horizontal where water can collect. Must be covered with paint. Famowood is the "best" I have used, good adhesion and doesn't shrink. It can't be stained, though.
Beat it to fit / Paint it to match
I can agree with your template advice, I had envisioned trimming after a rough cut away from the final line..I for get that some do full template cut outs. I rarely do that due to bit chatter or multiple passes. A jig saw or bandsaw leaving a 1/16" is my method.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
"If Brains was lard, you couldn't grease much of a pan"Jed Clampitt
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Thanks for the info. I was planning on cutting close to the line with bandsaw and then using the template/router set-up.
Kieran