Joining boards

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Geeze
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Re: Joining boards

Post by Geeze »

Hi Phil,

You're gonna LOVE that sled - I built a small one and Sledzilla which allows a 30" cut front to back. I use it for everything.

Russ
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Phil_S
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Re: Joining boards

Post by Phil_S »

Russ,
I'm not sure I can manage a 30" sledzilla. :roll:

Any advice on the appropriate size? The table on this saw is about 22" square. It's a job site saw, very portable, 45 lbs. I can move it outside where my work table is and then store it inside.

I've been watching a lot of table saw topics on youtube. Last night I watched a guy cut a dovetail joint that had that irregular hand cut spacing. It was precise and fantastic. There are many on building a sled, but there was one that I really liked. The guy showed how to make 5 cuts on a board to determine the amount of out-of-square error on the rear fence and then he corrected it so well it would probably meet aerospace specs. It seems there is no end of what can be done with a table saw. I'm going to love this tool.

Phil
Geeze
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Re: Joining boards

Post by Geeze »

Hi Phil,

Make the right side longer than the left so you can clamp stops for cutting matching lengths. Also have enough on the left side to support the cut off side. I usually clamp a block to hold that side down. I drilled and cut a slot in the rear wall to slide a squeeze clamp through to pull the board tight and hold it while cutting.

Front to back dimension can vary. For my first one I made it 14" as that was as wide of stock for speaker cabs I thought I would need. Since then I did one that was a 21" cube

ALSO - Have a 'safe' or 'no fingers' zone for your hands as there will be times when you can't see the blade. Guitarists are very unhappy with missing fingers!

Russ
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Phil_S
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Re: Joining boards

Post by Phil_S »

Russ:
I'm well aware this is dangerous and appreciate that you thought to mention it. I think that's why I've had it for about 2 months and still haven't tried it out. I've got a couple of books and watched a lot of youtube. Now, I've gotten some sense of what's terrible. I see guys doing whatever and I'm thinking, man, your fingers are too close and why don't you use the guard and anti-kickback gizmos. Where's your featherboard, and you should have grabbed the push stick sooner. I realize why people don't like the safety equipment. I just don't buy into that mentality.

I watched a youtube of a sled with a plexiglass guard running the length of it above the blade. It looked very effective and I'm going to see if I can dothat. It was just 3 sided box that inserts into a pair of slots on the front and rear fences. It rides high enough in the sled to allow for some height to the work piece and can easily be removed for any tall work you might have. It could be made to float down onto the work, but I'm not sure that's needed and might be a bad idea.

Thanks for the pointers on the sled. I'm thinking the first sled will probably be about 14 x 24. That way it won't be running off the table too quickly. I'll probably work out an outfeed system later that will allow the use of a larger sled. For now, I think I'm working with pieces that will end up final size around 10 x 20.
Phil
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TUBEDUDE
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Re: Joining boards

Post by TUBEDUDE »

Greetings Phil,
I don't t know if you have joined your cherry yet, (Nice looking wood), but I've had some good luck drilling holes in the centerline of the.joining faces and using dowel glued in about every 5 inches. It holds the boards from slipping when clamping at glued up.
Tube junkie that aspires to become a tri-state bidirectional buss driver.
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Phil_S
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Re: Joining boards

Post by Phil_S »

Hi! I haven't begun to cut or prep the Cherry wood just yet. I don't have a dowel jig (yet), and no drill press, so I'm concerned the holes will not align well and create more trouble, but thanks for the suggestion.

I've been working on the crosscut sled. It has taken quite a few hours. I'm taking my time. One serious impediment is making that first straight reference cut. Then, I had to make the back fence twice due to a newbie error, failing to consider the round blade cuts more on the face down side ;-(. I used a handsaw the 2nd time! The challenge is setting the rear fence square to the blade. On first shot, I had it off by about .00075" per inch. Over 20", that's an error of .015". I am the type who can't leave well enough alone. I figured (and seen on youtube, so it must be possible) that I could use a feeler gauge and a stopblock to adjust the fence to almost nothing. However, that attempt was futile and I move the fence back to it's original screw hole. When I did that, the error (by the 5 cut method) was only .00023" or about 5 mills over 20" ;-} So, go figure, I did better. I've got to add a rear safety housing for the blade and a plexiglass blade guard. I was able to use the sled to cut the blocks for the rear guard! I put a coat of Minwax paste finish on the bottom to help it slide. Here are a couple of pics.

This guy explains all of it very well. Though a bit long (36:55), it is well worth watching. https://www.youtube.com/watch?v=UbG-n--LFgQ The basic run down is about 14 minutes. Then he shows the right way to build it.
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Phil_S
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Re: Joining boards

Post by Phil_S »

It would be wonderful if I could find a little more advice on working with Cherry. I came to the realization, I've never worked with anything but big box store pine and some old Douglas fir that was removed from my roof when the tree fell on the house.

Slow progress on this head cab. First time around, new working with a table saw, all sorts of things that slow me down. I spent some time building various jigs, with some do-overs. I've now got two for ripping the first edge, one for 24" shorts and one for 48". The longer one is heavy and harder to control. I also built a more appropriate router sled jig so I could plane the lumber with a 1.25" bottom cleaning dado bit.

I've finally got the wood planned to about 13/16", but it was looking very rough. I was reticent to use a hand plane on it since my earlier attempts taught me the grain runs every which way on these boards and I was gouging the wood. I'm sure my technique leaves something to be desired, too. (The blade is properly sharp and works great on pine.) I finally settled on the block plane set very shallow. That removed a great deal of the rough fuzz. Then 220 sandpaper with an electric sander (front-back type that takes 1/3 sheet of paper, not the round disk type) took off more of the fuzz".

The questions:
--Do I bother to try to sand more to rid the board of all the fuzz Pic 2832)? See the picture, I'm pointing to some. What grit? There are spots on the wood where it is silky smooth and very elegant. Just not 100%.
--Does this get better when I apply some finish to the wood? (Note, wiped with a damp rag to show contrast of light sapwood and darker.)
--Should I apply some sort of light stain (what color?) to show off the grain?
--What type of finish? I'm leaning towards paste wax because I have some of that. I'm curious about people's preferences. This amp is for home use, so I can ignore considerations for gigging conditions.
--Cutting. The board in the pic is ~44.5" (pic 2836). I need to get the top (20") and 2 sides (10") out of it. It turns out the boards appear to be from the same tree -- not quite book matched, but pleasant enough at the joint in the middle. So, I want to cut 10-20-10. Should I cut and then sand or sand more and then cut? The bottom will be made from another piece, not shown.
--The joint shows in a few spots (pic 2833). It is imperceptible to the touch. Do I ignore this? Any way to hide it? It's not terrible. Considering I jointed it on the saw, it came out better than I imagined. I had to use clamping force to close a few spots and that seems to have worked, mostly.

Thanks in advance for any help you might offer.
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martin manning
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Re: Joining boards

Post by martin manning »

Cherry is hard and brittle, so it chips easily and burns if you feed too slow. I think what you have there is tear-out caused by the cutter edge getting under the grain, which is running out of the surface (not parallel to it). This can be dealt with by feeding the board through the planer in the opposite direction, or running the hand plane in the opposite direction. Curly boards have varying grain direction though, so one feed direction may be as bad as the other. It cold be that one of the glued-up boards has rising grain while the other has falling when viewed from one end. Sanding will ged rid of it, but you have to remove a lot of material. Drum sanders that are built like a planer are made for that. I would use 150 to take it down quickly without making deep scratches, then 220 and 320.
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Phil_S
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Re: Joining boards

Post by Phil_S »

Reading the grain on this wood proved to be challenging. I finally figured out that the grain pattern is like a topographic map. The concentric circles go up to the high points. The grain runs towards (or is it against) the mountain top.

Needless to say, this has been an eye opening experience. What I found hard to figure is the seller planed it, but that didn't take out the bow/cup or the twist, so what was the point? I'd much rather he'd sold it rough sawn. One thing, though, is that the wood was nice and shiny after he put it through the planer. I want to get it back to shiny.

Since the plainer is a router with a bottom cleaning bit, I can move it in any direction, but now I am done with that because I've glued up the boards and the sled isn't wide enough. Besides, I don't really want to take off another 1/8" or more. Also, it is too easy to leave a burn mark. Due to the bit diameter, I'm running the router at 18K RPM. This is the speed recommended by the outfit that sold me the bit.

What you say is useful helpful information, Martin. And it turns out your diagnosis is correct. (you seem to be well informed on all sorts of stuff, hat's off to you!) I was pulling the router towards me and it seems I should have been pushing it away from me ;-{. I will go with a more coarse paper and see what it does and then I can go back to the 220 and up to 320. I only have to deal with the side that shows ;-}.

Thanks.
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martin manning
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Re: Joining boards

Post by martin manning »

Phil_S wrote:Reading the grain on this wood proved to be challenging. I finally figured out that the grain pattern is like a topographic map. The concentric circles go up to the high points. The grain runs towards (or is it against) the mountain top.
The grain direction depends on whether the loop or arch was created by a hill or a valley. See below.
Phil_S wrote:What I found hard to figure is the seller planed it, but that didn't take out the bow/cup or the twist, so what was the point? I'd much rather he'd sold it rough sawn.
A board can change shape after planing (due to changing moisture content), but it could be that that the planing was not done correctly, and the boards were flattened by feed roller pressure, only to spring back on the way out.
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Phil_S
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Re: Joining boards

Post by Phil_S »

Yup, got more than enough of that going on...particularly at the joint, near the middle of the board, where there are two "mountains" close together, making it difficult, if not impossible to plane. I should have surfaced them better before joining. Sandpaper is clearly the answer. Learning things here. Thanks, Martin!
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Phil_S
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Re: Joining boards

Post by Phil_S »

Looks like a ghost town here...is anyone out there?

Modest progress. The diagram on which way to run the knife helped a great deal. I was able to use a combination of the #4 plane and sand paper. Top and sides are polished to 400 grit. I needed a middle strip for the bottom to make it wide enough and got that when I ripped the top/sides to width. Bottom is glued up and I planed off a good bit of the tear out. The knotty end is a big problem. Since it's the bottom, I won't be quite so picky. Now to sand the bottom and cut to size. Then I get to try out my new half-blind dovetail jig!
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JazzGuitarGimp
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Re: Joining boards

Post by JazzGuitarGimp »

Hey Phil, Great topic - I've learned a lot from all the posts here, as well as William Ng's videos. I am going to have to build a crosscut sled eventually.

Cheers,
Lou
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Phil_S
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Re: Joining boards

Post by Phil_S »

Lou,
My favorite craftsperson on youtube is Paul Sellers. He is strictly old school. I've seen a bunch of his excellent, no nonsense videos. He's articulate and makes his words count. The only power tool I've seen him use is a battery powered drill/screwdriver. Look for him. You'll be glad you did.
Phil
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cbass
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Re: Joining boards

Post by cbass »

Keep an eye on CL for an old craftsman jointer you can find one for next to nothing. new blades are $30 . It's hard to get true glue line rip from r a table saw unless it's well made and tuned good with a high end blade . Your joint looks solid those small gaps are pretty much just a visual defect if you're getting good contact on most of the joint.
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