Second Bandsaw Questions/Advice

[Ed Weiser]

Hi Everyone,
In what I'm sure has been discussed before, I'm interested in the current point of view of the SMC membership. I have a Felder FB510 20" inch bandsaw with ceramic guides that has usually been fitted with a 1" Woodmaster CT for ripping and resawing. I generally tension the blade to near maximum and get reasonable performance. I like the large table and ability to add Aigner extension tables easily. I recently sold my Laguna LTSEC which was a Meber-built Italian 16" saw because I thought I needed the extra room in my shop. I'm getting tired of changing the blades on the Felder and am thinking of going back to a 2-bandsaw shop. My question is whether to add a larger dedicated resaw (like a 20" SMC-Minimax) that will better tension the 1" Woodmaster CT (or Trimaster, etc) and use the Felder for smaller blades or continue to use the Felder for resaw and purchase a smaller steel-spined saw that will easily take blades down to 1/8". I want to avoid a much smaller table than the Felder and think that for smaller blades crowned wheels and a higher table to floor height would be nice, perhaps a Grizzly G0514X2: large table, 37" to the floor and 3 hp motor with crowned wheels.
Any thoughts/advice/suggestions/experience?
Thanks.
Ed

[John K Jordan]

Ed,

It would, of course, depend on what you like to make and how you work. In my own case I love having two woodcutting bandsaws for hobby use - one is an 18" Rikon and the other a 14" Delta with riser. I use the larger one a lot for preparing turning blanks and a little resawing and the smaller one is great with a smaller blade. Maybe visit a shop or two and try out the smaller saws - if you get one for use mostly for thinner stock with smaller blades you may find out that even a saw with a much smaller motor will work well.

If I had the shop space, I would LOVE a larger saw like the Minmax. I used a wonderfully huge old iron saw when in the woodworking shop at Berea College and it was a dream.

Hey, while at it get a bandsaw mill for the back yard. I have a Woodmizer behind the barn and it opens an entire new dimension on playing with wood!

JKJ

Hi Everyone,
In what I'm sure has been discussed before, I'm interested in the current point of view of the SMC membership. I have a Felder FB510 20" inch bandsaw with ceramic guides that has usually been fitted with a 1" Woodmaster CT for ripping and resawing. I generally tension the blade to near maximum and get reasonable performance. I like the large table and ability to add Aigner extension tables easily. I recently sold my Laguna LTSEC which was a Meber-built Italian 16" saw because I thought I needed the extra room in my shop. I'm getting tired of changing the blades on the Felder and am thinking of going back to a 2-bandsaw shop. My question is whether to add a larger dedicated resaw (like a 20" SMC-Minimax) that will better tension the 1" Woodmaster CT (or Trimaster, etc) and use the Felder for smaller blades or continue to use the Felder for resaw and purchase a smaller steel-spined saw that will easily take blades down to 1/8". I want to avoid a much smaller table than the Felder and think that for smaller blades crowned wheels and a higher table to floor height would be nice, perhaps a Grizzly G0514X2: large table, 37" to the floor and 3 hp motor with crowned wheels.
Any thoughts/advice/suggestions/experience?
Thanks.
Ed

[John TenEyck]

Are you saying you can't get at least 25K psi on a 1" CT with your Felder? If that's true and resawing is a critical task for you then you could either consider using a 3/4" x 2 tpi CT or a Trimaster or a 1" Resaw King blade in order to get more tension. That would allow you to go with a smaller BS for use with smaller blades. But I think it really depends upon what you intend to cut with the new saw as to how large it needs to be. I get by just fine with a 14" Delta for my smaller saw and rarely wish it had a wider throat, but if your work needs a wider throat then maybe the right decision is to use the Felder with smaller blades and get another 20" or larger saw that can adequately tension a 1" CT. Still find it hard to believe the Felder can't.

John

[andy bessette]

I have a 20" Agazzani with 1" carbide blade and a 14" Delta with riser block and 1/4" blade. Works for me.

[Tom M King]

I have a 24" that stays setup for resawing, an old Delta 14", and a 10". The 14" is the least used saw. If I was only going to have one smaller saw, it would be a 1412, or a 10-326. I put a lot into upgrading the Delta before the 10-326 came out, and sold for 900. I have wished that I had put the money that I put into the Delta into the newer steel framed saw.

[David Kumm]

The FB510 won't tension a 1" carbide blade anywhere close to 25000. so if you want to do serious resawing with carbide, the second saw needs to be larger or the blades on the 510 need to work with lower tension. Dave

[Van Huskey]

You are pretty wide on your budget (514 to Formula SP500, the current name for a MM20). If the 510 is not meeting your expectations and it seems to be tension related there are a couple of things to look at. First, are you truly close to max tension (very small gaps left on the spring) or just max tension on the saw scale, the X10 series doesn't have as much leeway but Euro saws tend to have a lot more tension than the top of the scale. Second, if you are seeing lots saw marks (not hesitation marks which are feedrate variations) those are mainly due to harmonic vibrations which can be reduced* with tension. You can either reduce the cross-section of the blade as John mentioned by going to a more narrow and/or thinner blade or switch to a variable pitch blade. Those options may prevent the need to go to a heavier saw. You should be able to get acceptable results from the 510. You are not going to get 30K psi with that saw, but since you have it you should maximize your results before moving on.

If you do go the "smaller" second saw route you seem to have set a budget of ~2k as the 514 will be about $1950 shipped. At the 2K mark I prefer the Laguna 18BX and the Rikon 10-347 (though I haven't priced it since Rikon increased prices due to tariff recently). For years Grizzly owned the 1K-2K value market but the recent Laguna and Rikon models have jumped them IMO. I do also really like a larger table for contour and frankly, prefer a larger table for curves than resawing.

My suggestion would be to ferret out if you are indeed at max safe tension and if not try adding tension. If that doesn't work I would try a 1" RK before jumping to a bigger saw. I suggest an RK over a Trimaster since the 3/4" Trimaster is not available in variable TPI IIRC.

If those work then you can save a lot of money with a "smaller" second saw. If not then you can go on to plan B.



* I said you can reduce the saw marks by reducing harmonic vibrations, what you will actually do is increase the frequency and reduce the amplitude (so there will be more but more shallow, which is preferable).

[Randy Heinemann]

Since you want to put more tension on the Felder 20" blade, is there something wrong with the resaw results you have been getting with your 20" saw? If not, there is no good reason to tension the blade more. Maybe it's the blade rather than the saw or some other setup issue. Anyway, if I bought a second bandsaw, it would be for cutting curves and smaller pieces which doesn't require anything bigger than a 14" (maybe not even that but it depends on your projects). It would be great to have a second saw and avoid changing blades on the large saw but, for me, there would be no good reason to buy another large saw. Think of all the other tools you could buy with the money you'd save buying a smaller saw.

[Ed Weiser]

Thanks to all for some insight. Additional info: Here is a photo of 14" wide walnut that I just cut 1/4" thick. The blade is a 1.3T Woodmaster CT. The saw is maxed out on tension (extent to which wheel will turn before bottoming out) minus one half turn. The cut was easy and uniform, hand fed. I still get the feeling that the blade could have more tension though. Could the blade be a little long? Felder specs 170" and that's what bandsawbladesdirect was asked to provide. When I detension the blades completely, there is about 1.5" of gap of blade above the top wheel of the saw. Any thoughts?
I will spend for another saw what it takes to get the right combination. I just don't want to duplicate what I already have.
7BxgWIblTGytAsTvCaVUhQ.jpg

[Tom M King]

Isn't the range of blade lengths on the machine somewhere-like inside the top door? I never order one at the maximum length.

[Van Huskey]

Thanks to all for some insight. Additional info: Here is a photo of 14" wide walnut that I just cut 1/4" thick. The blade is a 1.3T Woodmaster CT. The saw is maxed out on tension (extent to which wheel will turn before bottoming out) minus one half turn. The cut was easy and uniform, hand fed. I still get the feeling that the blade could have more tension though. Could the blade be a little long? Felder specs 170" and that's what bandsawbladesdirect was asked to provide. When I detension the blades completely, there is about 1.5" of gap of blade above the top wheel of the saw. Any thoughts?
I will spend for another saw what it takes to get the right combination. I just don't want to duplicate what I already have.

Regarding blade length if you are almost maxing out your spring then the blade is short enough for full tension, so no need to fret there.

If you are not seeing a lot of barreling in the cut (the center of the veneer being significantly thinner or thicker than the top and bottom edges) then the only thing you can gain with higher tension is better finish. If your hesitation marks are deeper than the vibration induced saw marks then better finish from the saw will not decrease the amount of material you need to remove to have a good finish. Make sense?

It appears from the picture that you have a reasonably good cut quality but the picture doesn't have enough detail to comment on how much better it could be by spending more money. I pretty much guarantee the saw marks will be less obvious moving to a Resaw King and that is a much cheaper option than buying a new "big" saw.

While the grass on the other side of the fence might be a little tastier the cost of getting to the other side is certainly not insignificant especially when you can green up what you have with some high nitrogen fertilizer in the form of a Laguna RK. That said if you want to spend more money we are more than happy to help you.

[John K Jordan]

Ed,

Perhaps you can measure the actual tension which might help decide what to do next. The gauges provided on bandsaws are notoriously inaccurate so you probably need to measure it with a bandsaw blade tension gauge.

I use a Starrett gauge and I was surprised at how much below the recommended tension my blades were. Instead of buying a tension gauge, you can use a digital caliper to measure the tension. John TenEyck once posted instructions which I've copied below, or read the whole thread:http://www.sawmillcreek.org/showthre...33#post2640833

-------------------------------------------------------------------------------------------------------------------------
HOW TO MAKE AN ACCURATE TENSION GAUGE for free or cheap
Needed: digital caliper, small clamps, math

By John TenEyck

(Measuring tension with digital calipers)
...the blade guides are removed or at least backed away from the blade. Clamp the vernier with about a 5" gage length so that each jaw is on the flat of the blade, between two teeth. On really narrow blades it's best to face the vernier towards the back of the saw in order to avoid the teeth altogether.

The basic calculation is Young's Modulus = Stress/Strain, where:

1) The Young's Modulus of steel is about 30 x 10^6 psi.
2) Stress, the value you are after - the tension in the blade in psi.
3) Strain = Deflection / gage length. The vernier measures deflection, and the gage length is the starting distance between the jaws under zero load.

So, you rewrite the equation as Stress = Young's Modulus x Strain = 30 X 10^6 x deflection/gage length

The gage length I started with was 4.768", so when I measured a deflection of 0.003" that was equal to a blade tension of 30 X 10^ x 0.003/4.768 = 18,876 psi.

My little Delta was more than maxed out with the 1/2" blade I was using. The Iturra spring was nearly fully compressed, the frame was distorted by nearly 0.010" and that pulled the upper guide completely out of alignment. The data showed that I can't really run more than about 12K psi on a 1/2" blade. But with a 1/4" blade I can run at nearly 25K psi w/o over stressing the saw. The 1/2" blade will still cut OK at 12K psi, but I have to run more slowly than I would if I could apply higher tension to avoid blade deflection.

John TenEyck's photo:
bandsaw_tensioning_TenEyck.jpg
-------------------------------------------------------------------------------------------------------------------------

Thanks to all for some insight. Additional info: Here is a photo of 14" wide walnut that I just cut 1/4" thick. The blade is a 1.3T Woodmaster CT. The saw is maxed out on tension (extent to which wheel will turn before bottoming out) minus one half turn. The cut was easy and uniform, hand fed. I still get the feeling that the blade could have more tension though. Could the blade be a little long? Felder specs 170" and that's what bandsawbladesdirect was asked to provide. When I detension the blades completely, there is about 1.5" of gap of blade above the top wheel of the saw. Any thoughts?
I will spend for another saw what it takes to get the right combination. I just don't want to duplicate what I already have.

[David Kumm]

Looks like a pretty good cut but a 1/4" slice isn't a great way to test as there is enough stock on either side of the blade to help keep it in line. Slice a similar piece at 1/16 or less. If that stays uniform within .01 over the entire 14", you are golden and should just look for the smaller saw. If the thin veneer causes problems, you have a different decision. Dave

[Ed Weiser]

Thanks Van, I kinda thought the blade length was not an issue but thought I'd ask since it's very difficult to accurately measure a blade that's already welded for length. The RK is about 1/3 less band cross section area (in a 1" wide blade) than the Woodmaster CT so I think the resaw results can only improve. Most of the lines on my cut piece of walnut were hesitation marks (I think) so I will probably order an RK in 170" length, 1" wide with variable tooth spacing--it's certainly less expensive than a new resaw. My memory of wide blade tension was based upon a 30" cast iron saw my dad had when I was a youngster--it was the first bandsaw I ever used. Bands on that saw were rock solid with nearly no deflection on lateral pressure. I'm surprised we never broke bands from overtensioning.
John, I remember the thread from John TenEyck describing the method using a digital caliper. I appreciate you refreshing my memory of the technique. I'm almost afraid to try it with the Woodmaster CT--perhaps I'll wait for the RK to arrive and compare the two.
I think I'll wait on the second band saw for now until the RK arrives.
Happy Holidays everyone and thanks.

[Van Huskey]

Good overview of using a caliper to determine strain:

https://woodgears.ca/bandsaw/tension.html