The Forestry Forum

General Forestry => Sawmills and Milling => Topic started by: blush on November 22, 2020, 09:16:17 AM

Title: Swing mill self build, help with basics needed
Post by: blush on November 22, 2020, 09:16:17 AM
Hello,

I would need some help with the basics of building a swing mill. Now, I'm a total beginner as far as machinery goes, never made anything similar. But, I'm from europe and there is no way you can buy one here, they just don't exist.

I've read old threads on the forum, but still I have a few questions. If the build will be successful, or if it even starts? Who knows, I apologize in advance :)

Here it comes (geez what a greenhorn)

Let's say I go with 3 phase el. motor.

1. Do I make and attach arbor directly on the motor shaft? Or, do I make  pulley and a belt? If the latter, is it about the RPMs that you can adjust with the size of the pulley?

2. Is this second pulley machined out of the same piece as arbor? Or do you somehow couple them?

3. Can you just buy the arbor for the desired saw blade?

4. To really "get wet", not like just in theory, I would need to buy the: motor (let's say 10-12 hp), a saw blade. Then I walk into a machine shop (explain what I need) and the rest I figure along the way. Is this the right way to go?

Thank you in advance.

Blaz  
Title: Re: Swing mill self build, help with basics needed
Post by: mike_belben on November 22, 2020, 09:44:42 AM
Slow down.  I applaud your efforts but you arent ready to purchase yet.  If you start buying parts now youll spend a bunch of money on mostly wrong parts at 100% retail.  


You know what you want to build and youve got internet.  Now study study study what has been done and what works.  Get on youtube and ask the DIY swingmill build guys what hp, what RPM, direct drive or belted ratio etc etc etc.  They have already failed and redesigned and will pour out the info you need.  There are lots of russian and polish swingmills and electric slabbers on youtube actually.  I get suggested vids on them all the time. 


During this study period, peruse junkyards and look constantly at local classifieds .. Just browse anything industrial, knock on doors, leave notes on junk or in mailboxes.  The parts are out there for pennies per pound.  Ive been hoarding junk and building almost free machines for about 20 years using this patient collection method.  You need a big junkpile, some tools and internet. And patience.  


If you have none of that, whip out the credit card and have one shipped from USA. 
Title: Re: Swing mill self build, help with basics needed
Post by: Iwawoodwork on November 22, 2020, 09:56:34 AM
Mike gave very good Info,  I have read/seen pretty well documented swing mill builds on the internet, you just need to search for the sites.  as Mike stated don't jump to fast . patience = $$$ .
Title: Re: Swing mill self build, help with basics needed
Post by: blush on November 22, 2020, 01:09:22 PM
I appreciate the advice. I just spent last two hours browsing russian forums, internet is a bitc*  :D

I will need to research much further. But there are two things I found repeating in all the builds:

1. They are all direct drive. 

2. They all use the more "common" blade design with tooth count like 20 or even more.  It would certainly be cheaper for them and me, compared to importing lucas.


So, there are blades like this going for scrap where I come from. I could start from there.

One more question though, how do you couple the arbor to motor shaft? Do you thread it on, and secure it with a bolt?
Title: Re: Swing mill self build, help with basics needed
Post by: mike_belben on November 22, 2020, 02:15:33 PM
You have a flange adapter hub built.  Say the motor has a 1" standard single key shaft.  Maybe start with a 3 bolt tapered two piece sheave so you dont have to broach in a keyway AND, so that if you switch to a 1-1/8 motor later you dont have to rebuild the whole thing, just buy another taper insert.  Martin is a good common brand of this stuff in america.  China makes tons of it too now of course.


Anyways.. Now you turn, dowel, drill and tap or whatever is needed to create the face mount to put your saw blade on it.  You cant build it until you have the motor and the blade in hand.  Most critical part of the machining will be A.. That it doesnt grenade and make you an amputee, and B, that the saw rim runs concentric and coincident to the shaft centerline.



Consider a VFD speed controller so you can fine tune the RPM a little for different species of wood.
Title: Re: Swing mill self build, help with basics needed
Post by: J D in AUS on November 23, 2020, 04:19:06 AM
Turbosawmill (https://forestryforum.com/board/index.php?PHPSESSID=p7pqmk2cmka1mtga6vvcpf1530&board=96.0)
 (https://forestryforum.com/board/Themes/default/images/rss.png) (https://forestryforum.com/board/index.php?PHPSESSID=p7pqmk2cmka1mtga6vvcpf1530&action=.xml;board=96;type=rss)
Title: Re: Swing mill self build, help with basics needed
Post by: nativewolf on November 23, 2020, 07:44:45 AM
There has been a used peterson for sale in the UK.  Not really Europe though is it  :D.  
Title: Re: Swing mill self build, help with basics needed
Post by: blush on November 23, 2020, 02:39:17 PM
Quote from: mike_belben on November 22, 2020, 02:15:33 PM
You have a flange adapter hub built.  Say the motor has a 1" standard single key shaft.  Maybe start with a 3 bolt tapered two piece sheave so you dont have to broach in a keyway AND, so that if you switch to a 1-1/8 motor later you dont have to rebuild the whole thing, just buy another taper insert.  Martin is a good common brand of this stuff in america.  China makes tons of it too now of course.

I appreciate your advice but, if may I ask, is this something like this BearingShopUK - Fitting and Removal of a Taperlock Bush - YouTube (https://www.youtube.com/watch?v=fT4axK3haQ0)  
- the pulley in the video being my adapter hub?
Now for another question, as I sort of a hit a wall in my search for a blade.
Cannot relly find much.

From what I understand about ripping everything depends on basically everything there is, teeth number, RPMs, type of wood, feed rate, .. Making it a bit hit and miss on the first time. Anyway, if somebody would take a look.

Offsite image deleted by Admin, refer to photo posting rules


18 or 24 teeth.

or this mafel blade MAFELL Kreissägeblatt 450x3,8/2,5x30, Z=12 online bestellen - sautershop (https://www.sautershop.de/mafell-kreissaegeblatt-450x3-8/2-5x30-z-12-maf-092537?c=15893)

12 tooth, and mafell screams quality, while the first one seems cheap (maybe because it is).

If none of these cut it (pun intended :)), I will search further. I don't want to base the rest of the build on the wrong blade.


@nativewolf (https://forestryforum.com/board/index.php?action=profile;u=24089)

Atleast for now no charging of customs tax  :D
Title: Re: Swing mill self build, help with basics needed
Post by: Ianab on November 23, 2020, 03:56:28 PM
Important thing to remember is that no part of the blade retaining system can extend past the outside surface of the blade.  As you are cutting in the horizontal plane the blade is skimming a fraction of an inch over the surface of the log, so no protruding nut or shaft will work. 

They usually use countersunk allen key bolts (high grade steel), that screw into a flange on the end of the shaft, then have nylock retaining bolts on the back to stop them working loose.  So an "off the shelf" edger blade like in that picture isn't going to work. 

Also the blade attachment is probably the single most important thing safety wise. If that fails things are going to go bad extremely fast. Think "2 ft sharpened steel Frisbee heading off in a random direction at ~70mph" bad. 
Title: Re: Swing mill self build, help with basics needed
Post by: mike_belben on November 23, 2020, 10:41:15 PM
Yes that is one style of taperlock.  I dont have the experience to help you on blade selection.  Sorry. 
Title: Re: Swing mill self build, help with basics needed
Post by: blush on November 24, 2020, 04:09:49 AM
@Ianab (https://forestryforum.com/board/index.php?action=profile;u=460) 
This I understand, it needs to be flush. So I would have to drill the 5 holes in the blade in a similar fashion to Lucas blade.

And yeah, it would be a killer move if the blade comes loose :D

@mike_belben (https://forestryforum.com/board/index.php?action=profile;u=33722) 
No worries, i'll try to ask the russians about the blade.
Title: Re: Swing mill self build, help with basics needed
Post by: mike_belben on November 24, 2020, 08:33:53 AM
I think you should consider buying a genuine branded swingmill designed blade and match it to the same rpm/hp motor it was built for.  That will probably be the best money you can spend on this project, since they have years in working out best performance.  



I would have a hard time drilling holes in an already heat treated and quenched high speed blade and risk creating stress risers, hot spots and the potential for catastrophic cracking.  And im not a safety oriented, "dont do that" type.  Significantly modding the center of a hardened blade may be very risky. 


If you decide to do it, investigate every single tone change in the cut immediately.  It may be the blade forming a crack.  A swingmill is one of very few machines that forces your body into the path of the blade.
Title: Re: Swing mill self build, help with basics needed
Post by: Don P on November 24, 2020, 09:02:27 AM
With a swingblade the pivot has to intersect the cuts into a corner exactly, that is a tall order.  I'd be tempted to build it with vertical and horizontal fixed blades that have that intersecting corner fixed and then move that assembly up/down, left/right. Then "regular" blades could be used and the precision of that corner isn't depending on a pivot.
Title: Re: Swing mill self build, help with basics needed
Post by: mike_belben on November 24, 2020, 09:17:12 AM
Ive had that exact thought myself don.  I would hafta do a lot of work to build in the adjustments to get that corner aligned perfect, so why not just lay out pillow blocks on a squared frame and run two shafts and 2 fixed blades.  


Then i figured why not just make a bandsaw with a ganged horizontal edger shaft that can be swing down and pinned and the belt walked on. 
Title: Re: Swing mill self build, help with basics needed
Post by: terrifictimbersllc on November 26, 2020, 06:35:16 AM
Did you consider starting with a blade and gearbox from Peterson or Lucas? That would take care of some of the more difficult issues. 

I'm surprised you could not purchase a Peterson anywhere in Europe.  Surely they must distribute them there.  When I purchased a Peterson 10 yrs ago it was built in New Zealand and shipped to me.  There was no distributor then in USA.