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John MacDougall
05-19-2016, 9:35 PM
Hopefully someone has experience close to this. I manufacture a wood baseball bat that I invented and it is made of two woods, "true" hickory and Tanoak. It is laminated in a unique way. If you looked at it from the end it would look like a pie of 12 pieces. If interested you can see it at MacDougallBats.com. The way I mill the triangular pieces starts with 4/4 kd lumber I then plane to spec. I then flat rip ~2" wide strips at 15 dgree angle. This "parallelogram" then gets ripped from short point to short point to create two slightly oversized triangular "staves". The flat ripping is no problem on the table saw with power feeder. The second rip, however, is a pain. We have always used the table saw with the piece up on edge, blade at 30 deg., sacrificial fence, power feeder on top at 15 deg angle, and a jury rig pressure wheel to hold tight against fence. See the rip guide jpg attached. This all works, but it is brutal. Hickory is HARD to say the least.

What I picture (when I have the capital) is a very heavy duty band saw for the angle rip with power feeder. We usually do about 3000 lineal feet at a time and these batches are getting closer together as we are growing. I can picture a time when this could be running almost constantly. Since the angle is 30 degrees, I would either have to tilt the table 30 deg OR tip the table 15 deg and tip the fence the rips run on 15 degrees. I'd like to be able to feed a minimum of 20 fpm but more would be better. The two large faces of the rip are about .030 oversize for final milling which we do to plus/minus .003".

The question! What kind of horsepower would be appropriate for this? I'm picturing 5 hp? Any advice on that and blade size/design would be greatly appreciated at well. Machine recommendation gladly accepted as well! You'd think making little triangles would be straight forward, but NOOOOOOOO. :confused:

Scott T Smith
05-19-2016, 10:49 PM
John, if it were me I would look at using some custom fixtures and a power feeder on a vertical band saw to make these cuts. If you use a Laguna Resaw King band you will have minimal kerf marks (typically around .010).

I think that you need to use a saw that will accept at least a 1" blade for production use or else the blade may deflect. 20FPM is a pretty significant feed rate; I don't think that 5HP will be adequate on a continuous duty basis - more like 7.5 - 10 hp.

Matthew Hills
05-19-2016, 11:18 PM
I don't have a good feel for production feed rates. Is 20fpm crazy high for ~2" thick?

John Erickson
05-20-2016, 6:37 AM
Do you cut the pieces from one piece boards or glued panels?
Do you dress the stock before you make the first cut or are you dressing the three sides after the pieces are cut.
My thoughts 5 hp is more then sufficient. Contact Lenox or equivalent for proper blade suggestions.
I'd glue up panels for the pieces so you have the least waste and have larger panels to hold while cutting.
I'd fabricate two power fed sliding table fixtures with position stops holding the panels while performing the cutting.
First remove the band saw table so you have the least amount of blade exposed from the guides and the fixtures are mounted as close as possible to the blade.
Mount the first table close to the bottom guide at the appropriate angle to cut the shortest angle.
Then mount the second table above the first cutting the longest angle piece having something to catch the piece being cut.

David Kumm
05-20-2016, 7:30 AM
I agree you should get a blade recommendation from Lenox. The RK will be too slow and you want a heavier band when operating a feeder. The saw will need to be stout for production work as a bandsaw feeder is heavy- 200+ lbs. The table trunnions will need to support the feeder and tilt at the same time. A saw heavy enough to handle the feeder will likely come with a motor large enough to handle the cut. Dave

Tom M King
05-20-2016, 7:45 AM
20fpm at 2" is not at all too fast for at least a 24" saw. I'd say 5hp would be plenty, but not sure about all day-maybe go up a step or two for safety. The Woodmaster CT is a great resaw blade, but the highest tooth count is 2 TPI in a 1" blade. That would be the blade I'd try first, as I don't know of a faster resaw blade. The tooth count is kind of low, but it cuts so fast and smooth that it would probably work.

Ideally, I'd say an even larger saw with wider blade and a few more teeth, but that's out of the range of anything I know about.

Rick Alexander
05-20-2016, 7:50 AM
I've toured a shop that makes staves for wine barrels in Missouri out of white oak - also a pretty hard wood - and they use a cnc controlled shaper to accomplish those crazy angles and shapes. The shop I visited was near Macon Missouri http://www.independentstavecompany.com/manufacturing. Wonder if a standard shaper with an angled bit in it might be a better bet to make that second cut? Or even a multi head molder to do all of it from the 4/4 stock? Seems like it would be less of a chore to set up and would be more reliably accurate and a smoother cut.

Robby Tacheny
05-20-2016, 10:06 AM
It seems like you should be able to find something like a multirip saw or gang saw that can run on a tilt or with a tilting table. Have you considered that?

Otherwise, the shaper does seem like an interesting prospect if you can deal with the waste.

Is finding a mill that can make you the blanks an option? Paying a little more per blank without having to invest the up front capital makes business sense.

Robby

Anthony Whitesell
05-20-2016, 10:21 AM
I think the key is achieving the 20 fpm feed rate. What type of tooth and band will it take to accomplish this? Based on the tooth profile, you will be able to see how big of a bite the blade will be taking and from that you can determine the horsepower required to pull the blade (teeth) through the cut. Based on the the thickness of the cuts (0.9" and 1.6") you may need two blades. With that said, I would also investigate a bandsaw setup for each cut no one has to keep adjusting the tables, power feeder, blades, etc. to switch from one cut to another.

Rod Sheridan
05-20-2016, 7:13 PM
Hi, watch this video...........Rod.

https://www.youtube.com/watch?v=SksCR69lhuQ

Kevin L. Waldron
05-20-2016, 11:23 PM
Enclosing a manual for our Northtect Vertical bandsaw...... very capable of obtaining speeds even faster than you request.......We have the larger saw and the pneumatic feeder.... ( We also have a horizontal saw by the same company that is computer controlled but it would not allow cutting on an angle without modifications. It is 30HP) Note the HP of the Vertical saw....20HP.....

I would also recommend a shaper or molder for faster cleanup....

kevin337783337784337785

Patrick Curry
05-21-2016, 3:10 PM
Super cool. Glad you've found market success.

If you haven't spent much time ripping or resawing on a large bandsaw you might want to approach a few local woodworking shops before making any equipment investments. I have a 4hp 18" Bandsaw with Resaw King blade and I'm just not sure this is the direction you want to go (feed rate and finish). I'm wonder if one of the larger sliders (sliding table saws) wouldn't be a better solution but I don't know that I'm picturing your 'difficult' cut.

Anyway, my suggestion is to find a well equipped local woodshop for a consultation. Let them figure out the most efficient way to meet your production runs. There's a good chance you'll find a shop that wold love to have something to keep their equipment running in between their more lucrative projects. And now that you'll have a little extra time on your hands spend it marketing the bat.

You can always bring production back in house later, and you'll know for sure which piece of equipment is needed.

michael foster
05-24-2016, 7:10 AM
sweet post, I had to to do something a while back making and gluing up wedges. I cut rectangles and cut the triangles out of the rectangles, diagonal cut. I glued them together and then cut off the outside edges to make it into a circle. More work on the lathe but less headaches on the saw. Just a thought. Improving production processes is good for the brain. Looking for the bats in the pro leagues. .
Michael

Martin Wasner
05-25-2016, 12:17 PM
A bandsaw isn't a good tool for ripping large amounts of material quickly. Somebody said 20 feet per minute, that's painfully slow. The cut quality dowon't be enough to go directly to glue up either. 4/4 in a straight line rip should be close top 100 fpm for a feed rate depending on the machine and the amount of power it has.

Making wedges would be a horrible pain in the rear. I'd think a having a dedicated insert cutter made to cut both of the angles in one pass would be the ticket, but you'll be turning large amounts of lumber into chips. You'd also have to have something on the outfeed side of the cutter to support it and ride on after the material has been removed. It all depends on what's worth more to you, more waste or more time wasted. Once setup, it should be just rip, machine, and straight to glue up.

Jim German
05-25-2016, 2:34 PM
I think a bit more business case analysis would make sense before selecting a machine for production work. You've got to weigh the operator cost, vs material cost, consumables(aka blades) and even power cost, in the end machine costs will probably be a very small portion of the overall manufacturing cost. If material is cheap you're probably better off going with a shaper or moulder as others have mentioned that will take raw material and spit out parts ready to be glued all in one shot. Where did the 20fpm come from? Is that what you think you will need running 8 hours a day all day to meet expected demand? There are plenty of industrial sized machines that could hit that easily with a good carbide blade, but it might make sense to look for a machine that can do two or three times than to save on operator cost.

Bradley Gray
05-25-2016, 3:40 PM
I think the OP has checked out. This was his one and only post and he hasn't commented.

John MacDougall
12-31-2016, 12:09 AM
I think the OP has checked out. This was his one and only post and he hasn't commented.
Sorry. I did check back on this but for some reason I did not get notifications. At that time I was also a one legged man at a butt kicking contest. Baseball season and all. My apologies.
Im still figuring this out as I'm still waiting on capital for new machinery. Starting a national sporting goods manufacturing business seems to be expensive. Go figure!

I do have to split the piece on the angle as using a moulder to do the initial shape would cut yield in half which would be WAY too expensive.

I have seen the Felder machines - very nice but VERY expensive. I have to build modifications anyway (as usual) so I think I will go as big as I can. Minimum 5 hp but perhaps 7.5. Also at least 1.375" blade capacity.

Thank you you all for the valuable input. No one else makes a bat like mine and not many people seem to have the machining requirements I do. I guess that keeps it more interesting! 😄
Cheers and Happy New Year!

Rollie Kelly
12-31-2016, 9:44 AM
If you are not going the way of resaw specific machines, I would start looking for Tannewitz or better bandsaws.
Go to the OWWM.org site and ask about recommended machines.
Hope this helps, good luck,
Rollie

Darcy Warner
12-31-2016, 10:00 AM
My 30" Yates Y30 will walk though anything I shove through it. It's only 3hp, but never been an issue. My old #16 Oliver us only 3hp and does almost as good as the Yates.

John MacDougall
12-31-2016, 1:36 PM
If you are not going the way of resaw specific machines, I would start looking for Tannewitz or better bandsaws.
Go to the OWWM.org site and ask about recommended machines.
Hope this helps, good luck,
Rollie
No problem with re-saw specific machines per se, just have to be able to tilt table and feeder. I just have to get "creative" with it. I will check out that site. Thanks.

Kevin Jenness
01-01-2017, 8:51 AM
For serious production you may want to look at something like this http://www.lobomachine.com/shop/item.aspx/12-x-12-hor-band-resaw/420/

peter gagliardi
01-01-2017, 9:31 AM
This is Basic Milling 101 for the most part. If your process is good until the splitting of the parallelogram pieces in half, all you need is a good 3-5 hp bandsaw of probably a 30-36" size with a 2 tpi x about an .030-.035 thickness carbide tipped band. Since all your stock is milled to one thickness, and you are doing only one rip, a regular 3 or 4 wheel stockfeeder is all you need.
Don't get talked into spending a ton of capital on a "new" old technology! Bandsaws haven't changed hardly at all in a hundred or more years.
A good U.S. made Tanny, Yates American, Crescent, Oliver, Moak, or Fay and Egan cast iron machine, or a good quality Italian or German machine- bigger Centauro or Meber type is all you need.

Here is the part that matters the very most-
Make a special fence or cradle out of wear resistant material - steel, or?? that leans ideally to the left at the 30 degree angle with a 15 degree base angle to hold the bottom edge. It can stop about 1/4-1/2" before the face of the blade teeth, and then maybe another piece just after the blade to catch the offcuts.
If you have a capable bandsaw already, and a feeder, it will be a few hundred dollars to make the cradle at a fab or machine shop.
If you are starting with nothing, you could get it all for probably $3-4k with just a tiny bit of looking.
This is easy, don't overthink it.

John MacDougall
01-01-2017, 5:52 PM
This is Basic Milling 101 for the most part. If your process is good until the splitting of the parallelogram pieces in half, all you need is a good 3-5 hp bandsaw of probably a 30-36" size with a 2 tpi x about an .030-.035 thickness carbide tipped band. Since all your stock is milled to one thickness, and you are doing only one rip, a regular 3 or 4 wheel stockfeeder is all you need.
Don't get talked into spending a ton of capital on a "new" old technology! Bandsaws haven't changed hardly at all in a hundred or more years.
A good U.S. made Tanny, Yates American, Crescent, Oliver, Moak, or Fay and Egan cast iron machine, or a good quality Italian or German machine- bigger Centauro or Meber type is all you need.

Here is the part that matters the very most-
Make a special fence or cradle out of wear resistant material - steel, or?? that leans ideally to the left at the 30 degree angle with a 15 degree base angle to hold the bottom edge. It can stop about 1/4-1/2" before the face of the blade teeth, and then maybe another piece just after the blade to catch the offcuts.
If you have a capable bandsaw already, and a feeder, it will be a few hundred dollars to make the cradle at a fab or machine shop.
If you are starting with nothing, you could get it all for probably $3-4k with just a tiny bit of looking.
This is easy, don't overthink it.
Peter, you're onto what I'm doing. I just need a machine I can set up and leave to do the same thing continuously. I had similar thoughts on the fence but was thinking to build it at 15 degrees and tilt the table for the other 15. Is there a reason the fence should be (lean) on the left of the blade?
I did find a Comatic DC30 3 wheel feed that is fully variable speed that looks like it may be perfect for this.

peter gagliardi
01-01-2017, 6:41 PM
John, no special reason for sled tilting to the left, except most saws have the main support to the left, and when the table is at rest against the 90 degree stop underneath, you can mount the feeder on the left of the blade, and extend the arm over the work, pushing the work left into the sled, leaving the weight of the feeder also at rest, rather than cantilevered out on the trunnion if u mount on the right.
If I have to do it, I would always choose to setup the sled to do all the tilting. That takes the possibility of table creep off your desired angle out of the equation.

John MacDougall
01-02-2017, 12:30 AM
Peter, thanks for the great information. That all sounds perfectly logical to me! I was thinking of some sort of "permanent" steel fence anyway so just making it as a cradle sled at the full angle makes sense. The "vintage" world of saws looks like it would take up way more time than I have for something like that. Any opinions on the Minimax S600p?