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Discussion Starter · #1 ·
I did some searching on the forums, but didn't see anything that matched this issue so I thought I would bring it up. I am currently restoring a Taiwanese clone of a Rockwell Delta 28- 200 model 14 inch bandsaw and can't seem to get proper tension on the blade. I can get it pretty close but in order to do so I have to crank the tension handle all the way down and this causes the upper wheel to hit the upper housing to the point that the wheel won't spin. If I take off the upper housing and just run the wheel bear and shim the tension rod I can get proper tension in the bandsaw seems to run fine. Any idea what could be causing this? I am using a standard 93 1/2 in blade which is what the manual I found for this saw states should be used. So far during the restoration process I've only changed out the blade guides and replace the old rubber tires with new urethane tires. Could the difference in thickness from the old rubber tires to the new urethane ones cause this? Is this simply a case of the bandsaw blade being too long and needing an off size? I've also noticed that the blade seems to be rubbing on one of the support pens for the housing case which once again makes me wonder if the diameter of the wheel plus the thinness of the urethane belt is causing the issue . I've added some pictures of what I'm seeing. Any help would be appreciated. Ps: forgive the messy shop new homeowner with a 1-year-old means not a lot of time to clean....

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where's my table saw?
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If the only thing that's been changed is the tires on the wheels, there's your answer.
If the same blade was tensioned OK before the tire change, it's the tires.
If it's a new blade, it could be a bit too long.
Depending on the amount of interference, I would just file some slots in the cover holes, enough to clear the wheels.
I'd try a different blade and see how that works.
You may be "stuck" having blades made to a 93" or 92.5" length, not a big deal.
 

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question is the wheel crowned or is the belt crowned.
both wheels do not have to be crowned. if you buy crowned tires and put them on crowned wheels, it will never track.
 

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Discussion Starter · #5 · (Edited)
If the only thing that's been changes is the tires on the wheels, there's your answer.
If the same blade was tensioned OK before the tire change,
If it's a new blade, it could be a bit too long. it's the tires.
Depending on the amount of interference, I would just file some slots in the cover holes, enough to clear the wheels.
I'd try a different blade and see how that works.
You may be "stuck" having blades made to a 93" or 92.5" length, not a big deal.
Unfortunately the saw did not come with a blade so i dont have that to go by as far as previouslength used and if it tensionedproperly. I did find a manual for this model and it states that it should be able to do a minimum of 91 1/2 to a maximum of 94 inches. After work im going to try and take some measurements and use a formula I found online , (R1 x 3.1416) + (R2 x 3.1416) + (2 x C) = Saw blade length, to see if maybe I need a non-standard size

question is the wheel crowned or is the belt crowned.
both wheels do not have to be crowned. if you buy crowned tires and put them on crowned wheels, it will never track.
So funny enough it's tracking fine. When I have the top covers off to allow me to tension the saw correctly it tracks and cuts just fine. Although I do think the new tires are thinner than the old rubber ones. I'm wondering if that loss of thickness is causing clearance issue with the case pin (see Pic above) and then that loss of thickness is also causing me to have to max out the tension which pulls the wheel far enough up to also cause the rubbing on the case (also in a Pic above)
 

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where's my table saw?
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Unfortunately the saw did not come with a blade so i dont have that to go by as far as previous length used and if it tensioned properly. I did find a manual for this model and it states that it should be able to do a minimum of 91 1/2 to a maximum of 94 inches. After work im going to try and take some measurements and use a formula I found online , (R1 x 3.1416) + (R2 x 3.1416) + (2 x C) = Saw blade length, to see if maybe I need a non-standard size

So funny enough it's tracking fine. When I have the top covers off to allow me to tension the saw correctly it tracks and cuts just fine. Although I do think the new tires are thinner than the old rubber ones. I'm wondering if that loss of thickness is causing clearance issue with the case pin (see Pic above) and then that loss of thickness is also causing me to have to max out the tension which pulls the wheel far enough up to also cause the rubbing on the case (also in a Pic above)
Normally, the rubber tires are fairly thin and the urethane tires are slightly thicker, just my observation. If you still have the old tires compare them to the new ones.
An increase of 1/8" in diameter on both wheels that would raise/increase the internal circumference. This would mean that a given length blade would have a shorter distance between centers, the opposite of what you are experiencing.
I would sill recommend trying a new blade at 93.5" and see how it works. You may have received an over spec length blade, and without cutting it apart and measuring the length, we won't know. Any machine shop of note will have a blade welder, even I do, and be able to perform that test and remove a 1/4" or more if needed. Check one out locally and get a new blade regardless.
 

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where's my table saw?
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??????
Absolutely no reason to cut a bandsaw blade, just to measure the length of said bandsaw blade.
With the exception being the damn thing is too long as it is now. I say cut it or (have it cut) take an inch out and reweld it. It ain't workin' now, so fix it.
Get some new ones:
 

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With the exception being the damn thing is too long as it is now. I say cut it or (have it cut) take an inch out and reweld it. It ain't workin' now, so fix it.
You may have received an over spec length blade,
Measure it, if out of spec just return it. Most reputable companies warrant their blades to be in spec. If the blade is such a cheap knockoff, that the company will not replace it for an out of spec condition, it would be questionable at best, to invest additional time and money into said blade.
 

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where's my table saw?
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Unfortunately the saw did not come with a blade so i dont have that to go by as far as previouslength used and if it tensionedproperly. I did find a manual for this model and it states that it should be able to do a minimum of 91 1/2 to a maximum of 94 inches. After work im going to try and take some measurements and use a formula I found online , (R1 x 3.1416) + (R2 x 3.1416) + (2 x C) = Saw blade length, to see if maybe I need a non-standard size


So funny enough it's tracking fine. When I have the top covers off to allow me to tension the saw correctly it tracks and cuts just fine. Although I do think the new tires are thinner than the old rubber ones. I'm wondering if that loss of thickness is causing clearance issue with the case pin (see Pic above) and then that loss of thickness is also causing me to have to max out the tension which pulls the wheel far enough up to also cause the rubbing on the case (also in a Pic above)
I missed this statement above.

Normally, the rubber tires are fairly thin and the urethane tires are slightly thicker, just my observation. If you still have the old tires compare them to the new ones.
An increase of 1/8" in diameter on both wheels that would raise/increase the internal circumference. This would mean that a given length blade would have a shorter distance between centers, the opposite of what you are experiencing.
I would still recommend trying a new blade at 93.5" and see how it works. You may have received an over spec length blade, and without cutting it apart and measuring the length, we won't know. Any machine shop of note will have a blade welder, even I do, and be able to perform that test and remove a 1/4" or more if needed. Check one out locally and get a new blade regardless.
Thinner tires would cause the circumference to be reduced, causing the wheels needing to be further apart! It may be that simple, BUT the manuals range of lengths doesn't fit that scenario. Weird. Back to an out of spec blade, being too long.
 

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Discussion Starter · #16 ·
OK so some updates. One the thickness of the new tires are about half the thickness of the old tires (orange new, black old) see picture
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. So I'm sure that's not helping my situation, especially in regards to the rubbing on the housing pin. As far as the blade length I used the formula above and estimated the working position of the wheels and came up with (R1 x 3.1416) + (R2 x 3.1416) + (2 x C) = Saw blade length, (6.75 x 3.1416)+(6.75 x 3.1416) + (2 x 24)= 90.411. Now I don't know what exactly the correct C (distance between center of wheel hubs) is because they are supposed to be space at working distance and I have no idea what that is since my tension slide has no markings, so I did my best estimate. Even adding another inch to C still only gets me to a blade length of 92.411. So I guess I will try to get a blade some where in that range to try. The two blades I have that are supposed to be 93 1/2.
 

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@qnels001

If I may suggest.
take a standard tape measure using it backwards wraparound the two tires with the current setting. you may want to use a small clamp or masking tape to hold tape measure in place. blade still on.
if you have a tape measure that is Marked on both sides it is easier otherwise a Sharpie or crayon Mark the tape on the back side so you can see what the distance is.

this part will get a little bit more challenging. loosen the tension wheel so you're about halfway down the travel.
re-measure again you may have to use several pieces of masking tape to hold the tape measure in place as you go round the wheels.
do it for third time at the least travel distance and that will give you the minimum blade size.
this should match the owner manual. I have seen where the convert from metric to inches and be wrong.

also if have the model number and share it. may help others with the same problem or others who have the same saw.


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looks like it is at max travel.
 

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If I may suggest.
take a standard tape measure using it backwards wraparound the two tires with the current setting. you may want to use a small clamp or masking tape to hold tape measure in place. blade still on.
if you have a tape measure that is Marked on both sides it is easier otherwise a Sharpie or crayon Mark the tape on the back side so you can see what the distance is.
The other option I have used is to wrap a piece of string around the blade path and then measure the length of your string with a tape measure. The string is flexible enough to handle the radius of the wheels without a problem. Just be sure to put reasonably consistent tension on the string between measurements. Tape like Biotec recommended will hold the end of the string in place on the wheels. This is an easy way to get a blade length.
 

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@qnels001
on page 9 it shows a 93.5 blade length
on page 13 it shows 92.5 blade length
on page 16 it shows 92.5 blade length


i still think you should check mid position and minimum position on the adjustment since the manual does or does not have the correct length listed.
 
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