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Re-saw attachment, my weekend project!
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Author:  Shane Neifer [ Mon May 17, 2010 1:52 am ]
Post subject:  Re-saw attachment, my weekend project!
I haven't posted a new jig or fixture for a while so I thought I would add this one for those of you who are serious about re-sawing. This idea came from Bruce Crepps of Notable Woods (google him and see his on his website). Bruce did a great write up on his version of this fixture and on setting up a Hitachi B-75 in an issue of American Lutherie.

My saw is a Hitachi B-600, an older (and more sturdy) version of the B-75. It is a great saw, especially for cutting back and side sets. I have another larger saw that I use for cutting spruce and cedar tops sets. Anyway, I have been meaning to build this fixture for as long as I have had the saw (a little over a year and half or so) and I have some nice maple and walnut in the shop that one of our members had delivered to be custom cut so I thought it was time to invest in getting this fixture done. I think I have 10 or 12 hours in the construction of this thing, but my geometry and design is a bit different than Bruce's so I was designing on the fly. I have used it to cut a bit of Mahogany it works great! It is super important to keep your wood tight to the fence when resawing back and side sets to get maximum recovery and although I have had only a couple of small issues in the past this just makes it a fool proof job. This unit is driven by a single air ram which has regulated air pressure (I am using about 35 pounds right now). You can even saw boards that taper or are irregular as the the air pressure can be adjusted to offer a cushion effect to keep the wood against the fence. So here are the pics:

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Open 1.jpg


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Open front.jpg


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Open back.jpg


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Closed.jpg


Hopefully this will give some others the inspiration to add something similar to their rig!

Thanks

Shane
Author:  Robbie O'Brien [ Mon May 17, 2010 8:33 am ]
Post subject:  Re: Re-saw attachment, my weekend project!
Looks like you stayed up overnight thinking about that one Shane! Well done! [clap]
Author:  Chuck [ Mon May 17, 2010 9:15 am ]
Post subject:  Re: Re-saw attachment, my weekend project!
Would the wheels work better than a series of featherboards stacked on top of each other with wood spacers between the featherboards? I had thought of building one using a series of featherboards but the wheels look to me like maybe it is a better way to go.
Chuck
Author:  Shane Neifer [ Mon May 17, 2010 9:31 am ]
Post subject:  Re: Re-saw attachment, my weekend project!
Chuck wrote:
Would the wheels work better than a series of featherboards stacked on top of each other with wood spacers between the featherboards? I had thought of building one using a series of featherboards but the wheels look to me like maybe it is a better way to go.
Chuck


The real beauty of feather boards, is that they allow the wood to move in only one direction. So for a table saw or router there is an added level of safety with their use as they act as anti kickback devices as well. The down side is that they do also add a bit of friction. For bandsaws the force is entirely vertical from the blade so there is no issue of kick back and the wheels add no resistance and also allow some irregularity in the face of the piece of wood that is against the wheels. It is important to note that you do want the pressure as close to in front on the teeth as possible but onto the blade or else the cut will bind. I have incorporated a stop on my jig so that the wheels won't continue their arc into the blade once the wood has passed through.

In summary, wheels work better in this application! Bruce used wheels from a power feed, they are tighter tolerances so are the same size. I used lawn mower wheels, I went to Canadian Tire with my calipers and sorted through the stack until I got three that were within a couple of thou of each other.

Shane
Author:  Shane Neifer [ Mon May 17, 2010 9:59 am ]
Post subject:  Re: Re-saw attachment, my weekend project!
Robbie O'Brien wrote:
Looks like you stayed up overnight thinking about that one Shane! Well done! [clap]


Yup, I have had a picture of Bruce's in the shop for a long time but you know how these things go, you don't really get anything figured out until you start it!

Thanks Robbie

Shane
Author:  Mike OMelia [ Mon May 17, 2010 11:51 am ]
Post subject:  Re: Re-saw attachment, my weekend project!
Shane, I assume you still must pre-adjust for drift, right?

Looks like a cool idea. But I do not think I could build from the pictures. I know you stay busy, but if ever you get some down time, maybe take it apart and trace the pieces and include minimal measurements? I would be willing to pay for such plans...

Mike
Author:  Shane Neifer [ Mon May 17, 2010 12:05 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Mike O'Melia wrote:
Shane, I assume you still must pre-adjust for drift, right?

Looks like a cool idea. But I do not think I could build from the pictures. I know you stay busy, but if ever you get some down time, maybe take it apart and trace the pieces and include minimal measurements? I would be willing to pay for such plans...

Mike


Drift isn't much of an issue with saw Mike. The band is 3" wide and the wheels are steel. It is strickly a re-saw and built for that purpose, super solid for high tension and a very rigid fence. Mine never came with a motor but the original motors are all replaced by those that really use these saws. But the blade drift issue is uneffected by this fixture and if your saw has domed rubber tires on your wheels (as I had done on my larger saw) then adjusting for drift would be important.

Thanks

Shane
Author:  Daniel Minard [ Mon May 17, 2010 12:06 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Good one Shane!
I've been thinking of something similar for my new Laguna.
I was thinking of springs, but your air ram is a better idea. Completely adjustable.
It's not high on my to do list, 'cause I don't cut that much hardwood. But one day...
Author:  Bobc [ Mon May 17, 2010 6:22 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Shane it looks good but I'm not sure what you mean by this "You can even saw boards that taper or are irregular as the the air pressure can be adjusted to offer a cushion effect to keep the wood against the fence"
Author:  JohnAbercrombie [ Mon May 17, 2010 6:34 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Shane-
I've never worked much with pneumatics - are the hardware items (ram, controller valve, etc?) expensive?
Sources?

Neat idea- after 'pushing' stock against the fence for a while, I can sure see the advantage of something like this!

Cheers
John
Author:  Shane Neifer [ Mon May 17, 2010 8:16 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Bobc wrote:
Shane it looks good but I'm not sure what you mean by this "You can even saw boards that taper or are irregular as the the air pressure can be adjusted to offer a cushion effect to keep the wood against the fence"


Hey Bob, The air ram is controlled by air pressure (I am sure you know that duh ) so you can adjust it to what ever resistance you want from like 5 psi to your compressors or components limits, like 150 psi. So if you have a board that is 2 inches thick at one end and 3 inches thick at the other the wheels will stay in contact at the same pressure, unlike a featherboard would.

Hope that is clearer than mud!

Shane
Author:  Shane Neifer [ Mon May 17, 2010 8:19 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
JohnAbercrombie wrote:
Shane-
I've never worked much with pneumatics - are the hardware items (ram, controller valve, etc?) expensive?
Sources?

Neat idea- after 'pushing' stock against the fence for a while, I can sure see the advantage of something like this!

Cheers
John


Hey John,
Princess Auto is my source for these. The ram was probably $28 and the valve (switch) was $20 and the regulator $40 or so. Then just some bits and pieces. You can run a bunch of things off one regulator and valve if you wanted to get elaborate with valve banks and stuff. I use these rams on the cnc table as well so have another regulator on the other side. I will be using this on almost every time I use the re-saw so I made it dedicated.

Shane
Author:  Mike OMelia [ Mon May 17, 2010 8:26 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Pneumatics are cheap on eBay. I hope we can talk Shane into making some tracings! ;-)
Author:  Mike OMelia [ Mon May 17, 2010 8:26 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Oops , double post
Author:  JohnAbercrombie [ Mon May 17, 2010 9:24 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Mike O'Melia wrote:
Pneumatics are cheap on eBay. I hope we can talk Shane into making some tracings! ;-)


Just a bunch of close-up pics might do the trick, and the ram size. Doing drawings can be time-consuming- and I'm waiting for Shane to get some top sets done! (He is busy!) [:Y:]

Cheers
John
Author:  Kent Chasson [ Mon May 17, 2010 10:05 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Thanks for posting that Shane. Yesterday I sanded down a set of walnut I got from Bruce and I can attest that his setup is worthy of looking at. The set I got was straight off his saw and I sanded about .005" per side to clean up all the saw marks. I think he's made more improvements since that article too.

I went the other direction with my saw. Instead of something to hold it to the fence, I eliminated the fence. I posted the prototype for this a couple of years ago and this is the final version. Basically just an XY table. Vacuum holds the board to the jig. Bump it against the adjustable stop to the right of the blade and lock down the X axis (vacuum also). Push it through and repeat. It makes for smooth feeding with hands well away from the blade.

I mostly cut dry wood which means some case hardening in 90% of it. I built this to avoid the slices pushing the stock away from the fence as they cup coming off the saw. Looks like yours may do the same thing with a little more simplicity. How much pressure can you get before you start to deflect your fence or something else?
Author:  Shane Neifer [ Tue May 18, 2010 8:29 pm ]
Post subject:  Re: Re-saw attachment, my weekend project!
Hey Kent,
I remember you posting your prototype and it is a good system that has a proven track record. That is the slicing off away from the fence. I am not all that familiar with the vacuum hold but I like it (and use it on my CNC and other places, all home made as well). But with the system I posted one is not restricted to length of board. On my other resaw I have a sliding carriage that I use to square split spruce billets and that is limited to about a 28" long piece (clamp fixture and carriage travel length). I used to have to make some modifications to do harp guitar sets (48") and then I bought a bandmill for them instead. On fence deflection, well it will deflect but one has to REALLY push on it. These hitachi resaws (especially the older ones) are not shy on steel so the fence locks like a "T" fence and all of the pressure from this holding device is right where the the fence is designed to take it. Anyway, this is just another design that I thought people could play with if they were so inclined.

Thanks Kent

Shane
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