Looking at trying to make my own tapered cores. I know several of you fellows are light years ahead of me on this one.

Spent the day in the shop yesterday and built a sled out of partical board and did mange to make some tapers at 0025/1 for a recurve I'm wanting to build. I used a mini drum sander from grizzly I bought several years ago to build dulcimers with. It worked "sort of" and I'm going to try'em.

Any of you bowyers care to share your set ups for doing this. This set up just ain't as accurate as I would like to have for cores!

Y'all take care, Old

I cut mine with taper jig on a table saw. Then touch 'em up with a block sander.

This is my sled I used a already tapered taper. Used it to make my sled from. So I used the taper as my sled to grind a thicker piece. I then glued a thin stop at one end for my lamination to butt a against. Jeff F

What issues did you have?

Several Jeff!

My sled is not level is one of them. I actually built 2 yesterday. First one the same so " I leveled it". Done a damn fine fob of it was making perfect parallels! OOP's! managed to pull the top piece off before the glue fully set and put another piece over my tapers. I had made a sandwich with the partical board with an 0025/1 taper between them. 2nd one worse! Managed to level the cores by flipping twice before I changed the height of the drum. But ended up get my butts thinner than I wanted. In the morning going to put a taper under the sled "opposite" direction of the one in the sled. See if I can't level it "correctly" this time! LMAO!

I think the rest of the problems just plain ignorance in trying to do this. Kept feeding the thin end "into the drum" and noticed several times that the cores were buckling against the stop. Part of that problem also was maybe trying to take to much off at a time. Fellow might want to feed the thick end in once the cores start getting thinner. Dad always said you learn more from your mistakes! Turned a whole lot of figured Shedua into saw dust and BTU's yesterday!

Will make the adjustments to the sled tomorrow and see what I got laying around other than my good stuff to run through it!

Y'all take care, Old

We're going at this a little differently. Your sander is vertical and mine is horizontal... but a lot of folks successfully do it the way you're doing it. Maybe one of them will stop in and offer more advice.

My sled is aluminum, but wooden ones work fine too. I have no 'stop' to keep the lams in place, instead, I stuck a piece of adhesive backed non-skid stair tread material on my sled's surface. The lams usually don't move, but I grip them and the sled together slightly with my hand as it's going in and coming out just to be certain. I'm using a horizontal thickness sander and it has two spring loaded rollers, one on either side of the sanding drum, that help push the lams down against my sled... this also helps the non-skid surface grip the lams and keep them from slipping.

Once they're parallel and ground all over, I grind the taper and as I'm doing so, generally feed the thin end of the lams in first.

http://www.buildyourownbow.com/how-to-make-a-simple-thickness- sander-for-bow-laminations/

I made one of these. It works but I find grinding lams a pain. I use both a stop block and sandpaper on my sleds.

I swear I'd build more bows if I had a performax

Mine is so simple to use it feels like I'm cheating :^) I have one sled that is hinged and fully adjustable and my lams are as accurate as any I've ever bought.

I also use it for double tapers, wedges, and backings and lams for all-wooden backed bows, tri-lams and such. Now if I could just figure out how to adequately thin and taper raw bamboo splits while leaving the outside as-is.

"I swear I'd build more bows if I had a performax"

I doubt it, if you are doing high amateur numbers. You spend most of your time playing with the performax. Every time you change something, you run the risk of blowing a whole belt, and they are time consuming to change. I had one of the orginals, and the owner couldn't tell me how to adjust it for parallel, so I just jigged it. When they work perfectly they do a good job, but the main reason I had one was guitars, where a lot of the wood is crap. In bows, a lot of the is, or should be, really really good, though a lot of people like fancy un-bow woods also. Point being, you can cut clean wood almost any way you like but a 1K set of rosewood for a guitar that is half rotten and the other half burl, that calls for a sander. Not trying to tell you you are wrong, just maybe you should be happy. If you aren't you could check out the cheapest Grizz the OP has they are around 400.

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As far as the OP's problem:

- is your belt new, the correct grit for the passes you are taking (err towards coarse), are you running feed and speed correctly.

- If the base board of your jig is run through the sander first, it will then come out with the built-in taper the sander, or your process may have. This nets to zero the error.

- How is your taper secured to the jig, and which way are you feeding it. And what is the grain slope in your strip.

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There are easy jigs to use for hand planing if you prefer that approach. If you don't know how to sharpen or plane, it is a relatively long road though.

I made a jig out of aluminum,that hinges as well. works for any taper, and easy to make.

make sure your sander is square with your table or you will give yourself fit's. You used the term "level" i'm assuming you meant square. Level don't mean a thing, as long as your sanding surface and table are square with each other.

I would also abandon the partical board. never was a fan of the stuff.

forgot to add...i use my taper jig with a drum sander, or a sanding disc on the table saw, both seem to work ok, but i prefer the drum sander, the rpm's are not as fast.

Jeff & shade I'd like to see pics of these hinged sleds. The adjustment screw must be flush or recessed? Thanks!

Me too. I'd like to see your setup Jeff

A pic from the salt mine.I always use this kind of a setup,even when i was at morrison

No adjustment screws in mine. I use shims. Quick and easy. I'll post pictures when I get home this afternoon.

Just got out of shop, damn its cold out there. Here is a shot of my set up before I ran the sled through to see if I could true it up.

I am going to build an aluminum one Jeff but wanted to go cheap with the partical board. 3.25! Found a place where I can get what I want about 90 bucks +shipping. Going with 1/2" plate and I like your hinge idea to make it more versatile. Shoot it ain't rocket science to get different tapers, just a little math on how much to raise the other end of it! Will probably do that with set screws myself, maybe shims. Also thinking about maybe putting a DRO on the sander. Might do a build along might help some other fellow trying this!

Picture of the sled did not come out, but the sled did!! It's now +/- .001 from side to side and exactly .090 difference from end to end. Checked the Master Crafters core that I had taped under it and its an exact match of the core! Can't wait to run some lumber through the sander, see how this new sled works.

I don't plan on making a habit of making my own cores. Hoping that Belcher will come through with what he's doing. But it would be very handy to have an accurate taper set up if I need something in a pinch!

Many Thanks to Y'all for your help!!! Old

Here's mine.

Hinge end.

I also added supports on the sides to eliminate deflexion as the drum sander exerts some downward pressure... and they can be seen along the side. There are two on each side.

They're slotted to work with any taper. Once the appropriate shims are in and the unit is closed, the keeper bolts are snugged and griding ensues.

Shim assortment. I have way more and a bigger variety than I'll ever use... overkill ya know :^)

Well Jeff as friend use to say to me "anything worth killing was worth overkilling" LMAO!

Brother that's one hell of an FN set up! light years ahead of what I was thinking. I was planning on a center support for my sled also, but never thought of just using bolts on the side.

Gotta ask, you got a machine shop and built this or did you have someone else build it? Damn that's a hell of good looking sled!

I had a machinist weight-relieve the bottom and make the hinge. I drilled and tapped holes for the shim pins and side supports, made them, made the shims, etc... the peripheral stuff.

I have access to an industrial thickness sander and use a sled. This allows me to grind in the hundreds. Then to finish I use the grinder that Black Cheetah recommended that I built from Buildyourownbow for thousands. These grinders work great and can be very accurate with practice and a bit of tweaking.

That's cool! Definitely brainstorming some cheaper diy hinged sleds. Thanks And yes the byob grinder I referenced above works very well

That's a nice sled Jeff. Just like a sine plate. What is the overall length? How important are the lightening holes in the lower plate? Did you have the shims made too? What shim thicknesses do you recommend for good versatility without overkill? Thanks a lot. - John

It's 40" long.

Skeletonizing the bottom plate removed some serious weight. I would like it even lighter... so I'd say yeah, it's important.

I made the shims.

I have shims from .005 to .125 and may have made too many of each size, but wouldn't want to be without any one size in particular. I use it for a wide variety of tapers for different types of bows, but if a fella only needed to make a couple different tapers, he could quickly do the math and only have to make a couple of shims.

How thick of a plate are you using? I was going to go with 1/2" 6061 but that "looks" thicker in your photos. How wide is it?

Do you suppose a fellow could drill out the top piece "side to side". make like tunnels through it to lighten it up more? I too think the lighter the better for this. A heavy sled could cause some problems.

I put my question on a couple other sites to see what would come up. Hands down Jeff you got the best one out there that I've seen! Its clean and its simple.

Thank you so much for sharing it! And thank all of you for your inputs! Old

Todd, I wouldn't drill through the width to lighten. It's too likely to weaken the plate lengthwise. If you really need it lighter, I'd mill "compartments" out of the bottom of the top plate. Without a CNC mill, this would be time consuming. You could also waterjet a thinner plate through (like the bottom plate), then screw or weld a thin solid plate to the top of it. A lot of work either way. - John

John, you mean like this? :^)

We probably could have taken more, but I didn't have the side supports installed at the time, so the machinist didn't want to get too carried away removing material for fear of flexing.

Todd, the bottom is 1" thick and the top is 3/4" thick. It's rock solid. Sturdy means accuracy, but it's possible it would be just as rigid with thinner material. I would like to make one with 1/2" plates top and bottom, skeletonize the bottom and see how it does.

Oops, forgot to add... It's 4" wide.

Well Fisher if you did not get to carried away with the dia. of the holes. IMHO it would act like a truss of sorts. But I do see your point.

Anything worth killin is worth over killin. LOL. Yea Jeff that is pretty heavy duty alright. Did not think of fluting the upper plate either. And yes the more solid the better!

Let me throw this idea at y'all. Here is what I'm thinking after all of this. Would build the sled this way (2) 1/2" thick plates 2.5 wide. Skeltonize the bottom in shorter squares say 1.5 x 3. Flute the top plate through the center, one flute only. Use the side bolts to put it together. I've all the MC tapers that I need and can sandwich them between the plates as masters. If I need parallels or veneers, just bolt it together with nothing in between. It would be rock solid and light this way IMHO.

Like I said, not interested in core production but if I need it I need it. The sled would probably spend most of its time making thin stock for overlays and such

So what's y'all 2 cents on that idea? Old

I would make it 4" wide to be able to grind lams in matched pairs.

I have never ground a lam or made a bow, but I'm a Model Maker (Machinist) at a Government R&D Facility, so I have made and used a lot of machine fixtures.

Every improvement comes at a cost of time/money and you have to determine when something is good enough. Jeff's sled looks about as good as it gets in the important ways. Rigidity does result in accuracy and weight usually increases rigidity. Still, it can be detrimental to handling in the shop and might be an issue if it is hanging out of the grinder unsupported.

Old, Rigidity is most important running lengthwise. I believe any amount reduced by drilling horizontally would either weaken it lengthwise, or be insignificant in weight reduction. Think of a jungle suspension bridge versus one made on top of horizontal support beams. I would definitely keep the (metal) shims in place during use, because they then form a continuous triangle of support with nothing acting as an unsupported lever. The more locked down side supports, the better too.

The biggest issue in making one of these is drilling and tapping holes for the hinge (accurately) in the end of a 40" bar. To me, the most practical solution is to drill and tap it by hand as carefully as possible, then attach the hinge block BEFORE machining it into a hinge. Welding it on before machining it into a hinge would probably be even better.

I hope I don't sound like a "know it all." This looks like a very worthwhile project though and I'd like to be helpful. Thanks everyone for sharing. - John

I agree with John, that sled looks great. Gonna build myself one with a few of my own quirks. The sled I now use produces a perfectly tapered lam but HEY, I am bored and need a project.

James

Yes Jeff that's a good idea, would need to build it a little wider maybe for my recurves. I use 2" cores and glass in them. Give the cores a "little" elbow room make sure something is not hanging off the sled. Not to be "bull headed" but for what I want to do the narrower sled should be fine. Agree that yes it will be slower, but as long as I'm paying attention should still make matched cores IMHO. If need be can always "upgrade" later!

No Sir, John, not looking at your comment like you are a know it all. It is obvious you know some things about structure that I don't and your input in this project is most appreciated! Scripture about in the council of the wise is safety! Also light weight and rigidity is a top concern. The cores could very easily get end snipe with a heavy sled, and have problems if it bows in the middle going under the drum! Don't plan on hinging the sled either. Would use Jeff's side bolt idea to lock the sled in place and to clamp down on the master taper. That would make it solid as though I was running a 1" aluminum plate through the sander.

Well James you know the old saying "if ain't broke don't fix it!" LOL. But your going to have to share your sled now!

As a side note prototyping my first ILF riser this wknd. Got the prettiest piece of pine 2x4 you ever seen! LMAO yeah I know sounding a little ADHD. Just another part of the things I'm working on. I work 6 days a week and I seem to be always trying to put 10# of *&^% in a 5# bag. But hopefully all this will come together in a few more months and I will have a lot of things to share with all of you.

Y'all take care, Old

I hear ya on the bag stuffin. I've had one day off work since January. Worked 80 hours this week. We moved in June and I'm still putting my shop together. I need to get some chips on the floor and dust in the air!

YOU GUYS GET BAGS??? We just get "all you can eat!"

Todd, it didn't even occur to me that the hinge is pretty unnecessary. A good wedge or clamping arrangement attached to the top of the bottom plate would be much easier to make and maintain. With a solid stop, it would be plenty repeatable using various shims. - John

Pretty funny John, but yeah does sum some things up LOL

Yeah John it would be a lot like my wood sled just 6061 aluminum instead. The stop would be bolted down so I can take that off for running veneers or parallels on the sled. Or maybe just build another wood sled for those. Wait and see on that one!

Damn Jeff, 80hrs a week! That does suck! You really do need to get to the shop!

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