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Graham Knight
09-30-2005, 08:36 AM
Has anyone used tongue and groove strip planking such as sold by Robbins Timber (http://www.robbins.co.uk/Pdf%20Files/pl1_bs_cedar_and_caulking.pdf) ?
I wonder if it offers any significant advantage over the bead and cove type? They refer to it as "Rapid Strip" implying that it's quicker to use, I'm not convinced of that but it would certainly be easier to machine yourself than bead and cove, as the T&G could easily be cut on a table saw.

paladin
09-30-2005, 12:13 PM
The Rapid strip material does not have a square tongue or groove as does normal flooring...it's rather a sloppy fit to allow the material to "sag" or bend when placed around groove a curved hull....then you plane or sand the material to a "round" configuration...personnally I think it's more work than bead and cove. With bead and cove there's less filling the grooves that result from the sloppy fit. They also claim that you don't need to scarph the joints....but I would never butt material like that and expect to have no problems later...personal opinion.

JimConlin
09-30-2005, 01:04 PM
I'd think that both strip styles would take the same effort to mill. I'd do 'em both on a router table or shaper. I've made a guide jig for the router table that I can feed strips through continuously. It has four springy fingers that press the strip against the table and the fence before and after the cutter. The process takes two passes, first the bead edge, then the cove edge. Quite quick, really. Has anyone done a two-router jig to do both sides at once? I Might try that one day.

I'd think that there's only a structural reason to scarph strips if the strips are quite wide, say over 5x the thickness. Absent that, scarphed strips certainly look better if finished bright and if most of the boat's strips are the same length, it'd save labor to scarph up the planks of stock before slicing the strips.

Graham Knight
09-30-2005, 02:00 PM
I think I agree with you paladin, finishing bead and cove should be a lot less work as the strips will fit together better. Overall it should be quicker, and in my opinion better without all the filling, so I wonder what they think is so "rapid" about their Rapid Strip?
I would like to machine my own bead and cove strip, using the same method as Jim suggests using a router table and finger boards to guide the strips. The problem I'm having is finding suitable cutters to machine the radius I need to make 15mm (approx 5/8") thick strips, I can easily get cutters to make 6mm strip, OK if I was making a canoe maybe, but I can't find anything suitable for machining thicker strips.
With the cost of bead and cove strip I could easily afford to buy a top quality router and table and still make a huge saving. Someone suggested I'd probably burn out the router motor making the quantity I need, but that doesn't worry me as I could simply get a replacement under warranty if that happened!

Bob Smalser
09-30-2005, 03:16 PM
Originally posted by Graham Knight:
...Someone suggested I'd probably burn out the router motor making the quantity I need, but that doesn't worry me as I could simply get a replacement under warranty if that happened!Likely me. If I remember correctly, this is a much larger boat than whut most storebought bead and cove is made for and the linear feet of machining required is in the thousands?

To me that means a torquey, 3hp shaper, a power feeder, and several work days with an offbearer....not all-rpm-no-torque routers and fingerboards.

Shaper knives can be ground to any profile you like.

And remember that while T&G takes two passes thru the shaper, it takes 3 thru the TS unless you have a molding head....something I haven't seen in a long time.

No router is made to do that level of production work, and breaking off a half-inch bit at 20k rpm wouldn't be any fun at all.

Shapers aren't expensive, but the knives certainly are compared to router bits.

If you can find an old-fashioned molding head with detachable knives for a torquey TS, you can grind the bead and cove profiles yourself (or have a blackmith do it), and make your TS perform like a router table only edge up using the stock fence.

Those old molding heads were the cat's meow for large runs of straight beading....better than the big shaper....and if anybody finds a commercial-grade one, I want one too.

http://www.angelfire.com/mn/tomfelten/molding.jpg

http://cgi.ebay.com/ws/eBayISAPI.d ll?ViewItem&item=7549486184&fromMakeTrack=true (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7549486184&fromMakeTrack=true)

[ 09-30-2005, 05:00 PM: Message edited by: Bob Smalser ]

Keith Wilson
09-30-2005, 03:42 PM
AFAIK Delta and Ridgid still make them: Delta part #34-813, around $135 Amazon lists them (although I can;t get the link to work) or you could look here. (http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=34-813&go=5261) Ridgid part number AC-2008; look here about halfway down (http://www.ridgidparts.com/accessories/woodacc.phtml)

http://media.ptg-online.com/media/dm/Products/Accessories/ExtraLarge/20021129200000_34-813_72dpi_400.jpg

[ 09-30-2005, 04:49 PM: Message edited by: Keith Wilson ]

JimConlin
09-30-2005, 03:54 PM
I've certainly had a couple of 'Come to Jesus' moments with a molding head on a radial arm saw.

For 5/8" stock, i haven't found a side-cutting cove bit and i've had to use a core-box bit for the job. In cedar, this might work better with two cuts. The depth of the cove should be a touch less than deep enough to leave a feather edge.
5/8" core-box (http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_core.html) and bull-nose (http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_bull.html) bits are available from MLCS (http://www.mlcswoodworking.com/) and many other suppliers.

Bob Smalser
09-30-2005, 04:04 PM
Radial arm saw? Like Dad's big old DeWalt?

Crosscutting with it only for me, thanks. That's all we did with them in commercial shops.

Wuz always afraid of those things....and from my experience, once you get them to cut perfectly square you better leave them that way, because they don't easily repeat it. ;)

But like I've said.....IMO, relying on the router for 10,000 linear feet of machining is setting yourself up for failure.

[ 09-30-2005, 05:08 PM: Message edited by: Bob Smalser ]

JimConlin
09-30-2005, 04:40 PM
In 1970, the RAS was sold by Sears as good for everything. We learned otherwise .

I didn't hear what size boat was contemplated and had maybe 1500 LF in the back of my head. 10,000 LF would take some hours and chew up some gear. I might look for alternatives.

John Meachen
09-30-2005, 05:53 PM
I think it would be a good idea to find a traditional joinery business in your part of the world and ask them to quote for producing the strips .It might seem expensive,but have you costed the purchase of the machinery to do the job plus cutters,extraction and personal safety equipment?You are also more likely to reach the end of the project with a full compliment of fingers.Not that routers are particularly dangerous,but spindle moulders,referred to by our American friends as shapers can be.

Ellis Rowe
09-30-2005, 08:00 PM
I use t&g strips as the first layer in cold moulding. I find them to be a little quicker than cove and bead, and easier to keep fair and clean. Brooklin Boat Yard and Brion Rieff use them for the same reasons. I'm not familiar with the rapid strips. I just have my supplier mill the strips.
Jim, I have set up two routers to mill both sides of cove and bead strips. One of the routers has to be inverted for proper feed. It worked fairly well, but took a lot of fiddling with to get it right. I use a shaper with a power feed for most work of this type. Not only are the cuts more consistant with a power feed, but there is the added safety of having that shaper head under the feed.

Graham Knight
10-01-2005, 05:05 AM
Likely me. If I remember correctly, this is a much larger boat than whut most storebought bead and cove is made for and the linear feet of machining required is in the thousands? Yes I think it was you Bob. The boat is a Selway Fisher Edwardian 21 requiring approx 600 metres (2000 ft) of strip.

I was looking at using a Festool 2000E/1-Plus (http://www.axminster.co.uk/product.asp?pf_id=19824&recno=15) router for machining the strip. It's industrially rated and with a 2kW motor it ought to be up to the job.
It's an expensive bit of kit, but I've done my sums and I'd still save more than 50% over the cost of ready machined strip. There's also an advantage that I could buy the timber for the strip in two lots as I need it, saving storage space and spreading the cost.
I already have the neccessary extraction and safety equipment in my workshop, in fact I already have two router tables but I'm not sure the DeWalt routers would be up to the job. I suppose I could always try one and budget for a replacement if I wreck it!

There's still the option of simply using square cut strip of course, that would be the easiest and by far the cheapest way, and probably quite quick with the saving in machining time offsetting all the filling work afterwards.
I suppose it might be possible to machine at least some of the strip with a slight bevel for a better fit?