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Stock guides for a 20” bandsaw

rimcanyon

Diamond
Joined
Sep 28, 2002
Location
Salinas, CA USA
I’m looking to buy or make stock guides that I can install on a 20” bandsaw. I’’m familiar with commercial bandsaw stock feeders, but I really don’ t have the room or budget to go that direction, and I have too many projects to think about making my own feeder. I was thinking about using a set of vertically aligned rollers to apply pressure towards the fence, just in front of the blade. I did some internet searching, but have not found anything like I have in mind. It is easy to find stock guides for a table saw or shaper, but not for a bandsaw.

This is for cutting large beams into smaller stock for door-making, not for cutting veneer. KD VG DF 3X6’S are not commercially available (except by special order), so milling my own lumber is my best option. I usually buy 20’ 6x12 Select Struct DF green at the local lumberyard, then cut off 8’ so I have an 8’ and a 12’ beam to resaw into (4) 3x6’s. If I am careful selecting lumber, I can usually find boards that will work. Almost always they are face-sawn, so slicing into 3x6’s yields quarter-sawn boards (VG). Occasionally I find a VG 6x8 or 6x10 -then I can get some VG 3x8’s, or 3x10’s, so both fence and guide need to hanleup to 10”. However, its hard to feed the beams and get an accurate cut (the beams weigh 150-250 pounds), so the idea is to add a stock guide that will make it easier to get a consistent thickness. I need to make (12) 2 1/4” 8’ doors, which requires about 290’ of 3x6’s.The 3x6’s and 3x8’s get kiln dried over at Jekyl Hardwoods in Santa Cruz.

The bandsaw is a 20” Rockwell with a Reeves drive and a 3HP motor that has roller infeed and outfeed tables. The fence is a 1” steel vertical bar welded to a plate that gets clamped to the table. I was thinking of making the stock guide the same way, but since the shaft for the rollers would be smaller, I would add a triangular support. The drawback for this system is that there is no way to automatically advance the guide rollers after each cut, the plate will need to be unclamped shifted and reclamped.
 
Pushing 250 pound beams thru a bandsaw sounds like a real chore! My experience with band re-sawing is with veneers, but the concepts are not that different at all. I used to use a cobbled up gizmo with my 36" Tannewitz that got me great results, +/- .005" with .060" veneers. Somewhere I have a photo, but I can't find anything since I moved, so I'll describe what I did as clearly as I can, maybe it will give you some ideas.

To keep the stock on the fence, I used 3 maple pressure "fingers" contacting the board just in front of the cut, at the top, middle and bottom of the board. They were levers, pivoting on a vertical shaft, and the force came from cables attached to the outboard ends, going by pulleys, to a weight (bucket of scrap metal). If I can;'t find the photos I'll try to draw it for you.

My fence was nothing special, just wood, but I covered it with self adhesive UHMW tape to reduce friction. The more force you have pushing the stock into the fence, the more important this becomes.

I used a hand operated winch to pull the stock thru the cut in a very controlled fashion. Winch mounted on the table, cable going to a pulley mounted on a very long outfeed table, back to a carrier made of masonite. The masonite had to be a bit longer than the stock, had bolted on attachement in front for the cable, and a cleat to catch the wood at the back. Easy to just crank and get a smooth feed without taxing my strength.

It was kludged prototype, all sorts of patches and mods drywall screwed/5 min epoxied on, but it worked. Only expense was cheap Grainger winch and some aircraft cable. I always intended to remake it properly with a power drive, but never got around to it while I was still making furniture. I got the accuracy I needed, and resawed all sorts of really expensive highly figured and exotic boards, up to 22" wide!

I've since built a much more sophisticated version for resawing 3" wide banjo rim laminations. Roller fence w/ oilite bushings, powered by a variable speed dc motor, with rubber feed roll and pressure applied by a pneumatic cylinder. I just stand there an feed blanks, and they come out perfect. Gonna make it high enuf to turn my wood stash into guitar sets and retire.

BTW, I'm using a 20" Powermatic for this, works just great when it's tuned up.
 
I found this photo in a Northfield brochure, it sure looks like something that would work on my Rockwell saw:

Screen Shot 2020-10-18 at 6.32.05 PM copy.jpg

Richard, the guide on the left is similar in concept to your design, I think. I like it. The fence on the right, both the single roller and the multiple roller, are also interesting. My fence does not have a roller, it is 1" bar stock and allows the cut to be angled. What puzzles me about the Northfield design is that there is no provision for angling the stock to accommodate the blade set.

Dave
 
I just picked up one of those saws! Mines the 28-654 variant, thought I haven't gotten it up and running yet. I need to find an appropriate FVD since it's 3 phase.

Anyway, I know the power feeders are pretty pricey in general, but if your need is primarily doing the same thing (resawing your boards) you might be able to work up power feeder. (I saw one video of a guy do it for his table saw using a power drill)

Here's another discussion I saw about that idea that seemed more relevant.

Want to make a re-saw power feeder for bandsaw - looking for advice
 
If the table is big/substantial enough, a regular power feeder will work.
Can it be assumed that you have some sort of sturdy auxilliary infeed/outfeed tables set up to support the heavy stock?

I don't use this set up for veneers, which tend to be tall & wide. But it works well for thicker/wider stock so long as the ratio of thickness to height(width) is appropriate. As yours would be. Strips in photo are for bending into arches for outdoor landscape feature.

There is a slight downward bias of the rollers.
OTOH for balks the size you describe, the feeder could even be horizontal, with a heavier bias toward the fence.
If your table is not large enough to bolt the base somewhere, it is relatively easy to make a table extension lip out of 4 x 6 x 1/2" angle, ground/milled/or planed to bolt on one side or the other of the existing table. Bolt the feeder to that. It adds a convenient lip for clamping the fence, too.

https://www.practicalmachinist.com/...t-lam-arches-282845/?highlight=redwood+arches

Some pix from above post.

smt_bentarch3.jpg


smt_bentarch4.jpg


smt_bentarch2.jpg


smt
 
If the table is big/substantial enough, a regular power feeder will work.
Can it be assumed that you have some sort of sturdy auxilliary infeed/outfeed tables set up to support the heavy stock?

I have been considering a regular power feeder. I don’t have one for the 8” jointer either, so it could be put to additional use. The issue I can see is feed rate. Resawing feed rates need to be a lot slower for deep cuts, especially with green douglas fir. The gullets just can’t clear the sawdust fast enough, and there is a lot of resin build up. Even when cutting by hand, I find I have to slow down the cut or I run into problems. I’ve ordered a new 2tpi Lennox carbide blade, hopefully that will work better than the Wood Slicer blades I have been using.

I have 18” x 7.5’ roller infeed and outfeed tables on the saw. They are new, haven’t tried them yet; once I get the edge guide sorted I will be doing a run. I am also going to slow the blade speed down, it is currently on the “wood” setting, which I think is 3000 fps. I’m away from the shop this weekend, so that number is from memory, I could have the actual value off or the units off.
 
The issue I can see is feed rate. Resawing feed rates need to be a lot slower for deep cuts, especially with green douglas fir.

I used to resaw doug fir, but it is not commonly available on the east coast anymore.
You didn't mention any deep cuttting? (6" was the deepest for your project?)

If you feel you have to go slower than the 8' or so on many feeders and actually plan to use it a lot, then get one that is 3ph, which tend to be cheaper anyway, and put a cheap vfd on it. (My personal attack might be be to change the gear ratio - most feeders have interchangeable gears to change the speed ranges, and exposed chain final drive that could be modified. But overall, a sub-$150 VFD would be a more convenient solution. )

I have 18” x 7.5’ roller infeed and outfeed tables on the saw. They are new, haven’t tried them yet; once I get the edge guide sorted I will be doing a run.

I've tried various roller supports for long/heavy materials.
The most reliable i've found is one or another versions of what is shown in the photos: a long, thick, flat plank well waxed. Roller supports could be made to work well if you can bolt them to the table or contrive a system to bolt them in place when in use. Roller bias is a factor for directing the board, can be stronger than expected. Of course that can be used as a positive factor.


I am also going to slow the blade speed down, it is currently on the “wood” setting, which I think is 3000 fps.

(Assuming you meant FPM) I don't think that will help you. You seemed to imply that gullet fill was your current limit on feed speed. Band speed should probably be around 4,000 fpm or a little higher. Maybe the saw needs a larger motor if you plan to power feed it.

That said, i don't really know if anyone has explored the lower limit of feed and cut efficiency? Knocking what, 30% off the band speed to increase torque the same amount and then slowing the feed until the gullets are not quite overwhelmed?

I guess what i am saying is that there is probably a lower limit for the band speed to be efficient and the only purpose to lower it below somewhere in the 4 - 5,000 sfm range is because you can't feed fast enough to fill the gullets so the teeth are rubbing more than cutting. Or, the saw does not have enough power to pull it at those speeds and fill the gullets (same problem from different causes). At which point slowing the band speed to get more torque to pull it through the cut makes sense, down to a point.

smt
 
I agree with Stephen, I can't see any reason to slow the blade down, would just increase chip load per tooth. Unless you want to reduce heat and then perhaps resin buildup. But a better way to reduce heat and buildup is to use a lubricant.

I used a Lenox Micronizer with their lube, worked really well with resinous and oily exotics like rosewood and ebony. And this was with a 36" saw running at 8,000 fpm. Got better cuts and better blade life. I think you could cobble something up with an airline lubricator and some tubing, if you don't want to invest in a minimum quantity lubrication (MQL) system. Or just brush/spray on some WD40 periodically.

As to the feeder, I used a vfd on my 3ph Elu continuously variable speed unit. Worked just fine, used it on the shaper too for really curly hard maple.

The Lenox 2tpi carbide blade should work great, reduce clogging, and last forever. Might take a bigger kerf, but if you have the stock to spare, no problem.

Also, +1 for Stephen's concern about in-feed and out-feed roller supports having a bias. I've had that happen when ripping long stock, the roller can lead the wood away from the fence, that's a pretty long moment arm. I'd prefer to have a ball bearing outfeed and infeed support, , planning to make one some day. Till then a waxed or UHMW covered surface works better for me.
 
Regarding the bias of the roller supports, I see your point. I will try it and report back. At this point the machining is pretty much done, the roller tables are ready for use except the diagonal bracing, which will get done tomorrow. The roller bias could be designed as a feature, if the rollers were able to pivot to align to the blade bias. Right now I have it designed so that the roller frames attach to the table in two places, so there is no ability to swivel, but I have been thinking of alternate mounts if this does not work out. I made a pair of hooks that are attached to each corner of the roller frame. The hooks slip over the fence guide bars, and the roller frame has legs about 5' from the saw. Both the infeed and outfeed roller tables are 7.5' long.

I also acquired one of the Northfield resaw roller guides, and I am redoing my fence, so it may be a few days until I get it all finished and make a test run. The carbide toothed Lennox blade arrived and it will also be part of the setup.
 








 
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