Bandsaw Questions

[radhak]

It's been 2 weeks since I got my BS (G1148) but have yet to cut a piece with it .

Received my parts order from Grizzly on friday, and have a problem still.

A. According to the parts list (below), I needed the 'set screws' (#62) for the lower guide blocks. I ordered and received these:



Funnily, the upper blocks also seems to need these (according to the parts list), but what mine currently has are these ('twist knob'?) :

.

And now, I find that the new set screws don't fit the hole (blue arrow). The hole seems to be a shade too small !

I tried and find they do fit the hole in the upper part (red arrow). Dunno what the problem could be.
To remedy, I want to get to HD and find a smaller screw/twist knob that fits. But how do I determine the size? According to the parts list, #62 is "SETSCREW 1/4"-20 x 1/4". Which of these 1/4" is the thickness and which is the length/height? And what does the '20' convey? (Just trying to see if I could get the right size bolt/screw/whatever in a single trip).

B. And while I got your attention, looks like I need to shim the left trunnion by 1/16". (I judged this with the help of a steel square against the blade and the table).
So what can I use as a shim, keeping in mind it will have to curve between the trunnion (#74, green arrow) and the table-bracket (#76)?

Parts list here:

[Knottscott]

"20" is the thread rate, 1/4" is the diameter and length. A washer should work as a shim.

[poolhound]

As scott says washers are good shims. if a standard size doesnt work or you only need a small amount shimmed I find cut up soda cans work well.

Beer cans would also work but you must make sure you have plenty of empty ones on hand

[toolguy1000]

i wouldn't shim between 74 and 76. if you want to raise that side of the table, either shim between 74 nad the underside of the table or shim between 76 and the saw's frame.

[LCHIEN]

1/4-20 x 1/4
says 1/4" diameter with 20 threads per inch and 1/4" long.

It's strikes me as highly unlikely it will fit one place 62 on the upper guide and not the same place on the lower guide. You might Try taking a 1/4-20 tap and gently cleaning out the lower guide's hole.

A set screw and a thumb screw can serve the same prupose, to lock the support bearing in place. A set screw requires an allen wrench /hey key to turn and set it while a thumb screw can be turned by hand without any tools. Of course the set screw is hidden and neater and is not in the way whereas the thumbscrew is larger and may interfere with things. ANy 1/4-20 threaded fastener could be used at this location including slotted or phillips head machine screws, hex head bolts, allen head screws , etc.

agree with toolguy about shimming not in the curved place but in the support locations. won't fall out, shims in one axis only, flat mount.

[SARGE..g-47]

Just a suggestion Rad.. what Loring said about using thumb screws on both upper and lower bearings. The first time you have to drag out a flashlight to attempt to find the set-screw head to tighten or loosen it... you will also know why I reccomended set screws top and bottom. Those thrumb screws are easy to find and turn under the table.

A case of: even an old blind squirrel finds a set screw head every once in awhile but... a blind squirrel can find a thumb screw about every time without any fret. ha.. ha... ha..ha..ha..

Good luck...

[radhak]

Update

Loring, I have to commend you on your faith in the machining process : I was able to extract a sliver of an earlier set-screw from that socket with the help of WD-40, a strong light-source and magnetized screwdrivers . And I only went looking because you were doubtful the upper and lower guides would have different measurements. Thanks! Now the same set screw fits, but I shall try and find thumb-screws for ease of use.

And as toolguy pointed out, the underside of the table is a better place for the shims (also mentioned in the user-manual which of course I read last). Seems like I should get 'electrical washers' for their thinness.

Thanks guys, for now. I'm sure to have more questions pretty soon when I start using the Bandsaw!

[LCHIEN]

Loring, I have to commend you on your faith in the machining process : I was able to extract a sliver of an earlier set-screw from that socket with the help of WD-40, a strong light-source and magnetized screwdrivers . And I only went looking because you were doubtful the upper and lower guides would have different measurements. Thanks! Now the same set screw fits, but I shall try and find thumb-screws for ease of use.

And as toolguy pointed out, the underside of the table is a better place for the shims (also mentioned in the user-manual which of course I read last). Seems like I should get 'electrical washers' for their thinness.

Thanks guys, for now. I'm sure to have more questions pretty soon when I start using the Bandsaw!

I was sure the upper and lower guides were quite similar. Engineers are a frugal bunch, generally, especially those making things for mass production. We tend to reuse designs because it saves time and money and if the parts are correctly sized, redesigning will just come up with the same size screws for the same load inputs. Changing drills and taps is expensive. Using the same part two times instead of two different parts once each is also cheaper to inventory and stage for manufacturing and assemble (need fewer tools and tool changes).

As far as your shim goes, I did something similar, shimming under the table above the trunion on my Delta BS. Rather than trial and error, I measured the amount of elevation change over the length the blade of my engineer's square, using a feeler gauge (or you can measure over the width of the table using an engineer's square). tHE following relationship will hold:

Elevation change = E (mils)
Baseline of that change = B (inches)
Trunion spacing = T (inches)
Shim height = S (mils)

E/B = S/T
or rearranging,
S= T * E / B

using a larger baseline (Than the trunion spacing) should give you a smaller shim size than the elevation change.

You just have to find shims that add up to the desired thickness. Washers, coke can slices, brass shim stock in .005 and .010 etc from the hardwares store youc an cut with tin snips, all will work. I'd avoid plastic or other material which can or might cold flow under pressure.

this fit immediately and perfectly.