Author Topic: Gonna build a swing mill! (Read 14090 times)

TinMan · « **Reply #20 on:** February 04, 2009, 09:21:00 pm »

Firebass

I was planning to put my gearbox directly above the saw arbor, So the saw shaft and the gearbox output line up. Then use a high torque coupling to tie the two together (2 piece or a chain coupling) Mcmaster Carr sells them. Then I plan to run 3 groove pulleys on motor output and gearbox input....I like the way you built yours, makes sense. Do you think #35 or #40 chain would be big enough. My center unit may be lighter because I plan to go with mostly aluminum.

Tracy

Firebass · « **Reply #21 on:** February 04, 2009, 10:25:39 pm »

I think 35 might be a bit stretchy on my machine but on a light weight machine it could work. I think I could of used #40 on mine with satisfactory results. When I built my swingmill I had no idea of the torque that the blade would transmit to the main shaft so I decided to make the swing frame around a saw drive shaft I felt comfortable with instead of designing the saw drive shaft according to the gearbox. By doing this I feel I never have to worry about a broken saw arbor. Which could be catastrophic. I've heard of a owner of a $%^&* mill breaking a saw arbor before. I think they use about a 1" diameter saw arbor. I use a 1 15/16"... Way overkill but it wont ever break.

Firebass

Radar67 · « **Reply #22 on:** February 04, 2009, 10:37:52 pm »

Firebass, using this picture

Where is the actual rotation point on your design? At the gray areas next to the long rails, or at the outer blue squares?

Did you build an type of adjustment points in to adjust the blade up or down, left or right, or the yaw of the blade?

TinMan · « **Reply #23 on:** February 04, 2009, 10:40:15 pm »

Firebass

You can buy couplings that allow you to mate two different size shafts. I was thinking I would go bigger on the arbor for the same reason you just stated. It would really suck if the arbor ever failed

. Maybe 1.25 or 1.5 inch shaft . Nothing wrong with overbuilding. Now if that DanG gear box would get here i could get started building. Still doing some leg work on blades.

Tracy

Firebass · « **Reply #24 on:** February 04, 2009, 10:47:06 pm »

Those couplings are the best. What are you planing for shaft bearings? I thougt maybe tapered roller bearings would work in your case.

Firebass · « **Reply #25 on:** February 04, 2009, 11:07:59 pm »

Quote from: Radar67 on February 04, 2009, 10:37:52 pm

Firebass, using this picture

(Image hidden from quote, click to view.)

Where is the actual rotation point on your design? At the gray areas next to the long rails, or at the outer blue squares?

Did you build an type of adjustment points in to adjust the blade up or down, left or right, or the yaw of the blade?

All the blue rotates. welded to the blue ends there is a 1 1/2 shaft that is the main trunnion. The gray area is fixed with bronze bushings pressed inside of the steel tube welded to the frame (Grease Zert). I use shims on the cross rollers for left right vertical blade adjustment. I use the up-down chain for adjustment front to rear horizontal plain. Then I have a adjustment on my tilting mechancsim that lets me adjust the 90 degree rotation. Also on the 90 degree rotation I have a adjustment that lets me adjust simotaniously both horizontal and vertical indexes without lossing the exact 90 degree rotation. This works great for setting up to double cut. I started without this adjustment and it was just to difficult to get it tuned up by setting both rotation indexes.
In the picture below the green is the latch, red is the 90 degree swing adjustment and the yellow adjust simotainiously the vertical/horizontal index plain.

TinMan · « **Reply #26 on:** February 04, 2009, 11:15:10 pm »

Firebass

You think tapered roller bearings are the way to go? Was originally thinking just a quality 2 hole mounted flange bearing mounted directly above where the saw bolts on, and then the bearing in the gear box would be the support on the other end. Tapered roller would be more money I assume.

Tracy

Firebass · « **Reply #27 on:** February 04, 2009, 11:50:05 pm »

I'm not a big fan of block bearings for precision use. Just make it hefty enough that your confident your not going to shear off a saw arbor

Your life is at stake.

bandmiller2 · « **Reply #28 on:** February 05, 2009, 07:00:11 am »

Tracy,I like the firebass carrage it seems much more stable than the factory setup,no spring.To move the saw up and down what if you got the setworks off an old handset circular mill.Insted of the gears on the set shaft rap lets say 3/8 wire cable to four corners with an adjustable eye bolt on each corner.Set the pin in the quadrant one pull up an inch or whatever you set it for.Down twist the "D" handle and ratchet down.Have a look at one and you'll see what I'am talking about.Frank C.

TinMan · « **Reply #29 on:** February 07, 2009, 03:13:29 am »

FireBass

If i go with chain couplings I can run a bigger arbor, even though the gearbox shaft is one inch. You can mix and match to a certain degree. 1 inch to 1 5/8, I believe from Mcmaster carr. My buddy on the other side of the wall who has been a machinist for 22 years is gonna help me with the arbor..

Burdens sells the coupling, but they only rate them for 500 rpm?

Tracy

Captain · « **Reply #30 on:** February 07, 2009, 03:59:18 pm »

I just knew Tracy would be back in swing sometime

In reference to the arbor size, Steve's (Firebass) design allows a more substantial arbor size than simply adapting the outshaft of an existing gearbox.

When I build my NEW swingmill (hopefully this summer/fall, need a building to put in in first

) I am going to use Steve's design principles and separate the gearbox and the saw arbor. I had the concept in mind before he built his mill, but he beat me to it

Good luck on your design and I'll help any way that I can. Now to just convince the wife to let me buy and endmill and lathe with some tax return money.

Captain

TinMan · « **Reply #31 on:** February 07, 2009, 06:11:31 pm »

Captain

How are ya? You knew I would come back?

Still trying to round up a blade, funds are in short supply these days so Im trying to shop around some. Got any smokin deals on 8 or 10 inch blades (Used?) Been eye balling baileys selection of Lucas blades. Seems to me there was some talk about Lucas blade not being able to take full depth cuts in harder woods?

I got a local guy here in Grants Pass that may be able to get me a tipped blade for a reasonable price, although he hasnt yet called me back..

Tracy

aburge · « **Reply #32 on:** February 09, 2009, 12:32:06 am »

Tinman, been away from the computer but it has 79 hrs now only 71 when I picked it up. Working on putting some pics
up but seems that I am a little challanged when it comes to computers.

Albert

TinMan · « **Reply #33 on:** February 09, 2009, 08:25:10 pm »

Hey Albert

That's still pretty low hours. I think it only had around 30 when I sold it to Steve. Cant wait to see pics of what your doing with it.

Here is a picture of the gearbox for my mill, just got it in the mail today. It is supposed to be a 1:1 buts its actually 1:1.5
Should work fine anyhow.

Tracy

Firebass · « **Reply #34 on:** February 10, 2009, 12:30:48 am »

Nice looking gearbox. I used a 1 .35 : 1 Gear box. Heres a spread sheet that I came up with when I was in your shoes that might be some help. You can change the numbers according to your specs. Because you have a 1.15:1 Gearbox you will be over speed on the saw blade unless you put a larger driven pulley on the input to the gearbox. Check that you have clearance for the pulley and belt when your in the "blade Vertical position" Nothing should be above in the area the blade cut depth (8 1/2"). In the data I change the pulley from what I used (3.95") to a 5" (what you would need), it could be to big. Take a look at the previously posted colored picture. On the Grey gearbox input pulley you'll see what I mean. I Suggest using a Jackshaft then you can change the ratio there. I run around 2000 Blade RPM . Captain has some good input on recommending RPM. Depending on what you get.

Below is the clutch I use.

PM me if you would like this in a excel spread sheet where you can change numbers to see results.
Motor RPM   2800   RPM
Motor Pully   3.95   Outside Diameter
Gear Box Input Pully   5   Outside Diameter
Gear Box Reduction   1.15   :1 Ratio
Gear Box Out Pully To JACKSHAFT   24   Teeth 2" TIMING BELT
Saw Arbor Pully JACKSHFT   24   Teeth 2" TIMING BELT
saw diameter   21.5   Inchs
Saw circumfrence    5.6287   Feet
Saw RPM   1923.478261   RPM
Rim Speed   10826.68209   Feet Per Minute
Saw Shaft Torque   68.26175407   Foot Lbs

Firebass

Captain · « **Reply #35 on:** February 10, 2009, 06:23:17 pm »

I can't find any fault with those numbers....

Captain

TinMan · « **Reply #36 on:** February 10, 2009, 09:14:14 pm »

Firebass

Im going electric to start with. The motor turns at 1725 rpm. It should be pretty easy to gear since the motor rpm is close to the blade rpm...

Firebass · « **Reply #37 on:** February 10, 2009, 09:36:45 pm »

Quote from: TinMan on February 10, 2009, 09:14:14 pm

Firebass

Im going electric to start with. The motor turns at 1725 rpm. It should be pretty easy to gear since the motor rpm is close to the blade rpm...

I forgot you were going electric. sounds good.

Burlkraft · « **Reply #38 on:** February 10, 2009, 10:05:05 pm »

Looks like ya got a good start Tracy

Keep the pic comin'

TinMan · « **Reply #39 on:** February 12, 2009, 10:23:03 pm »

Got some new pics

This is my prototype swing unit. Once I get all the bugs worked out it will probably end being made out of 1/4 or 3/8 steel, this one is .160 aluminum. These pieces were all cut on our CNC plasma cutter. It took me about four hours to draw the parts on Cad, cut bend and weld. If all goes well, I wont have to redraw anything when I go to make the finished one. there is plenty of room behind and in front of the blade to mount riving knives. Im thinkin this bad boy will swing both ways, hence the cutout around the input on the gearbox. I plan to mount the motor directly above the pivot point, maybe 12 inches up and have vertical guards on either side.

News:

Author Topic: Gonna build a swing mill! (Read 14090 times)