First go at making a mini/rail mill

[BobL]

But the biggest problem I see is clearance on the bottom. I rarely have enough room under the log and often I sacrificially cut the log mounting timbers for convenience. Other times vertical blade does not even cut through the log entirely due to the size of the log.

Yep I agree that is a problem but The benefit of not spraying sawdust all over the place comes with some limitations.


In addition I realise that the RiveJig would have problems in squaring the sides of logs, because,
- the variation in depth along the length of many logs would be too great to handle and I'd be continually having to adjusting the roller depths from underneath and it could even be outside the range of any spring.
- The slope of the side of the log would also ride the rollers underneath upwards and bend the blade away from the centre of the log.

The intention is to use the RiveJig on slabs and cants that already have a flat bottom and can be supported well above the ground. Slabs and some cants can just overhang a set of heavy duty saw horses. For square cants that are too big and have to be left sitting firmly on supports it would not be too hard to make a set of supports that have a notch in them to allow the bottom wheels thru the notch. It would then be a matter of using a crow bar to lever the cant over to allow the bottom wheels to match up with and pass thru the notch.

All good ideas folks - keep em coming.

 

[excess650]

Bob you do good work.
So tell me how did you get the wife
to leave you alone so you could build it?

The answer is quite obvious. Bob's been slippin' 'er some wood!:hmm3grin2orange:

Bob,
What kind of wood is that beside the blue beer bottle?

 

[BobL]

The answer is quite obvious. Bob's been slippin' 'er some wood!:hmm3grin2orange:

Bob,
What kind of wood is that beside the blue beer bottle?

It's called Banksia, it's stunning wood and has a funny Nut/fruit that looks like this

It's very hard to get in big logs, all logs split like crazy. I know a guy who lives in a banksia forest - he is a bit of a greeny but boy does he have some nice trees on his property!

 

[BobL]

Mini-Mill part 2

Here is another CS mount for the mini-mill. It uses the bar bolt mount mechanism - stronger than the clamp method but is unbalanced in the current form - will work better once the rest of the trolley is made.





Im also working on a 3rd bar mount .

 

[stipes]

Nice Bob!!!

I like that design!!!!

 

[BobL]

Minimill - more CS clamp mechanisms

Here is another Minimill clamp mount mechanism. I think this is the one I'll be working with. I like this one. Its strong, more adjustable and better balanced of the two bar bolt mounts I've made.



The CS is held primarily by allen bolts at A & B.


Bolts E&F hold the 2" x 1/4" vertical steel plate that can be replaced to suit different CS bar mounts.

Bolts C&C1 and D&D1 can be used to grip the bar. As well as providing extra bracing these bolts can be used to adjust the twist of the blade so the blade cuts parallel to the beam. This may be needed because there are quite a few bits of metal between the rail and CS. The way this is done is to loosen allen bolts at mount point A&B and then C&C1 and D&D1are used to adjust the blade twist, Then A&B are retightened. the amount of adjustment needed is small but it all helps.





If I was to make it again I would probably use 30 instead of 40 mm angle.

Now for the rest of the carriage

 

[Brmorgan]

I like it. My only concern is that the lower bolts might be close enough to the bar rail grooves to pinch a bit and cause some extra friction. Of course I'm only looking at a little picture here so it might not look as close in person. Just wondering because one time my Alaskan mount loosened up during a cut, and crept too close to the bar rails and pinched a bit. I was still able to cut, but it just felt like the chain suddenly got dull. After not noticing the problem for a couple minutes, the extra friction caused the bar steel to overheat & blue for a couple inches around the clamp. I soon noticed the smoke. No real long-term harm done, fortunately.

 

[BobL]

I like it. My only concern is that the lower bolts might be close enough to the bar rail grooves to pinch a bit and cause some extra friction. Of course I'm only looking at a little picture here so it might not look as close in person.

The blade twist adjust bolts are very close (< 1/16" from) but not over any part of the bar groove for a standard 2 ft Stihl bar so should work on all bars bigger than this. I wanted maximum leverage so I wanted them as far out as possible. Unfortunately this feature will not work on my 050 20" blade for my 50 cc Homelite but then again this blade is so narrow it is less important like it is for wider blades

 

[Raymond]

Damn Bob you just keep making these while we sleep or what?
Like I said Bob you do some good work.

My dad was a metal fabricator before he died. Doing all kinds of odd stuff. He was also a perfectionist. One day he had a friend of a friend come to see him with two old style mechanical arms. Somehow the guy lost both arms and wanted my dad to see if he could help him dial his arms in for him. I guess it was full of little cables and pulleys with many adjustments.

The guy had both arms laying on his bench with my dad studying them for a few minute. The guy started getting restless and told my dad he needed to hurry. Dad got pissed and said hey DUDE I've never worked on mechanical arms before, if I ain't quick enough for ya take'em somewhere else.

The guy went to apologize and said no that's not it..I just have to pee.
Dad give him back an arm, so he could piss. Then an hour or so later he give him back both arm and the guy was so happy said they never worked so good.

 

[BobL]

Damn Bob you just keep making these while we sleep or what?
Like I said Bob you do some good work. .

Thanks Ray. I actually lay in bed awake and spend a lot of times in meetings at work rolling these ideas around in my head and dreaming up variation and improvements. I get a little frustrated that I have WAY more ideas than I every can build or ever write down and spend way too much time in my shed on fiddling around with how to make these. Anyway - I can do this or go to therapy - and this is cheaper and more effective

Cheers

 

[dallasm1]

I really like this last mount of yours Bobl. These looks easy to fabricate and would add some serious stability to the whole rig. On my minimill with superstrut, the mounting is flimsy and I am using bracing arms on the saw. Even so the structure is not as strong as I would like and there are some vibrational issues.
I really envy the length of your days down under. What is the metric conversion for hours? 2.54 of ours to one of yours? Otherwise how could you get all of this fabrication done, mill the lumber, AND post detailed pics and notes on AS. Keep up the great work and try to find some time for

 

[BobL]

Whole Carriage : WIP

I really like this last mount of yours Bobl. These looks easy to fabricate and would add some serious stability to the whole rig. On my minimill with superstrut, the mounting is flimsy and I am using bracing arms on the saw. Even so the structure is not as strong as I would like and there are some vibrational issues.

I first saw a minimill about 2 years ago and I thought immediately of a number of ways it could be improved. I made some sketches in my books but this is the first chance I've had of working in it.

I really envy the length of your days down under. What is the metric conversion for hours? 2.54 of ours to one of yours? Otherwise how could you get all of this fabrication done, mill the lumber, AND post detailed pics and notes on AS. Keep up the great work and try to find some time for

Cheers Dallas! I have to say I have a very understanding other half. She goes horse riding as much as she like and I get to hang out in my shed. A pity works gets in the way

Remember this?

When here is the 3/4 made carriage


Top view


Side view, The whole carriage can expand to fit different side planks/beams.


Underneath view so that it can sit on top of another beam.


And one for luck.


Right now I'm making the teflon bearings for the bottom 4 wheels of the carriage. Even without the bearings it runs fairly smoothly.

Cheers

 

[BIG JAKE]

I thought I'd posted on the sawdust buildup on the wheels with the rigid mounts. I like your Rive jig I think that will work. If one spring(i'm thinking valve spring too) isn't enough you could put two on and make the second with adjustable tension if necessary so you can minimize friction. Might not be an issue though. Nice work Bob are you doing this with a stick welder? Looks pretty smooth. I've been thinking of a possible carriage down the road for my Ripsaw so I can bring smaller logs home in event of mechanical issues up in the mountains. That way I won't waste a trip. Or if I don't get as much cutting done as I'd like I can bring a few home too. Anyway I'm watching with interest and again, nice job on the mill and the nice projects for your wife! opcorn:

 

[BobL]

I thought I'd posted on the sawdust buildup on the wheels with the rigid mounts. I like your Rive jig I think that will work. If one spring(i'm thinking valve spring too) isn't enough you could put two on and make the second with adjustable tension if necessary so you can minimize friction. Might not be an issue though.

I'd like to work on this one right away but I gotta stop and do some chores next.

Nice work Bob are you doing this with a stick welder? Looks pretty smooth.

Yeah it's just a $60 elcheapo stick welder. I need a lot of flush surfaces to make this carriage work properly and I can't do those nice recessed welds with this welder so I pre-bevel all the joins/seams and then over weld and grind off the excess with a flap sander - that's why it looks so smooth. I reckon about every third welding rod ends up on the floor of my shed. I could take it around to BILs and use the TIG but I want to save that for the really hard jobs. I wouldn't mind a TIG tho' they are sooo . . cool!.

 

[stipes]

Looks great!!!!

I was wondering about the square tube vers. I beam ...Looks solid,,and liked the last mount you posted... Gotta make me one when I get time,,and the funds... Thanks for sharing!!!!!

 

[Kicker_92]

Right now I'm making the teflon bearings for the bottom 4 wheels of the carriage. Even without the bearings it runs fairly smoothly.

Have you considered eliminating the wheels and all movint parts and just make them sliders with UHMWPE or Teflon?

I'd picture a box around the tube, with low friction glides on all four sides and no clearance for sawdust to accumlate. With a ball end endmill, you could even install some graseless ball bearings inside to roll along the track like excavator turntables do.

 

[dallasm1]

Here is another Minimill clamp mount mechanism. I think this is the one I'll be working with. I like this one. Its strong, more adjustable and better balanced of the two bar bolt mounts I've made.

I love this mount. I have been thinking of an efficient way to quarter saw logs and I think your mount provides a solution. Have a look at this and let me know what you think:

This is from the end view, please imagine the picture rotated about 22.5 degrees to the right. (paint would not let me rotate the pic) The blue things are wheels. I am not sure if the wheels are necessary or not. A smooth sliding surface might average out any irregularities better.

And from the side view:

This borrows heavily from your designs. The beauty about this is that after you make a pass, you just pick it up, turn it around and go back the other way. No Rails.....

Pardon my clumsy attempts at the drawings, but I hope you get the general idea. What do you'all think?

View attachment 96146


[/ATTACH]

 

[BobL]

Have you considered eliminating the wheels and all movint parts and just make them sliders with UHMWPE or Teflon?

I'd picture a box around the tube, with low friction glides on all four sides and no clearance for sawdust to accumlate. With a ball end endmill, you could even install some graseless ball bearings inside to roll along the track like excavator turntables do.

Yep I have considered this approach several times but I am worried it would not be as steady or firm, as hard metal on metal contact. I even have some pieces of UHMPE and teflon in my shed where I half started this approach and I may well make one like that some time. I think UHMPE and teflon will be fine for a little saw but that stuff does flow and wear under pressure and it will need more adjustment and replacement over time if it is used with a bigger saw. The thing about my design is the wide range of correction possible to keep the saw vertical will compensate for any wear due to saw tilt.

RE: with low friction glides on all four sides
As I want my beam to be T shaped for extra strength the carriage can't go all the way around the 4 sides.

Cheers

 

[BobL]

Hi dallas,

Some good ideas there.

When I quarter sawed (I have only done it once!) I found rolling the quarter so that one of the flat surfaces was at about 22º to the horizontal allowed me to use my BIL mill (which has 4 wheels on the inboard side of the mill so that the mill) so easily to peel off boards it would not be worth making something special for this.

However, some improvements to your design could be



Rotate the log 22º and rotate the power head 180º so it was better balanced and add an extra (blue) wheel.
I would prefer to have the whole base sittin on wheels rather than hard metal to wood contact which although the wood surface is already fairly flat will add to the effort required - at least for us old pharts anyway!

Cheers

 

[dallasm1]

Hi dallas,

Some good ideas there.

When I quarter sawed (I have only done it once!) I found rolling the quarter so that one of the flat surfaces was at about 22º to the horizontal allowed me to use my BIL mill (which has 4 wheels on the inboard side of the mill so that the mill) so easily to peel off boards it would not be worth making something special for this.

However, some improvements to your design could be

Rotate the log 22º and rotate the power head 180º so it was better balanced and add an extra (blue) wheel.
I would prefer to have the whole base sittin on wheels rather than hard metal to wood contact which although the wood surface is already fairly flat will add to the effort required - at least for us old pharts anyway!

Cheers

There I go! Over thinking it again! I could probably easily modify a smaller alaskan with wheels to do as you suggest. Most of the stuff that i will be quarter sawing is only about 6 - 16 in after it is quartered. Thanks for your valued input.