Homemade CSM, first post

[cruckshank87]

Hello my name is Lindsay Cruckshank, or "Crankshaft" as my friends call me. I have been perusing this site for quite a while and would like to thank everyone for all the information you have posted over the years, it has been extremely useful . I first learned of chainsaw milling after reading the Jacqueline Tresl article almost two years ago, and have been addicted to CS milling ever since even though I still have yet to mill a board . I finally got an 088 a couple weeks ago and have been building a CSM with scraps of angle iron and other materials I had lying around. I drilled out the center of the nose and drilled two holes on the saw side to attach the mill to the bar. I still have work to do, like adding at least one handle and fabricating an aux oiler, but this is what I have so far. Any comments and advice are much appreciated!

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[rarefish383]

Welcome, I like it. Simple and sturdy. With the pre drilled struts all you have to do is change the bolt holes and you are dead level on every cut, no worry about being off by a 1/16 on one end or the other. now let the boards fly, Joe.

 

[Hank Chinaski]

nice and simple. Repped.

 

[Talltom]

I assume you have washers between the bar and mill since the chain is thicker than the bar? Chainsaws generate a lot of vibration & fasteners will tend to shake loose. Spring washers will help keep things tight.

 

[cruckshank87]

Yes, I have one washer in between the bracket and the bar on each of those 3 bolts so it elevates the mill about 1/8" above the bar. I also used lock washers on all of the bolts on the mill and got them pretty tight.
I wasn't sure how much torque I could put on the bar so I didn't tighten those 3 bolts too tight for fear of crushing the bar. Anyone have any thoughts or experiences with that?

 

[KiwiBro]

 

[Daninvan]

Good work, when are you going to put it to the test??

I like that you have drilled the nose to get maximum width.

I would suggest removing the dogs at some point if you can easily do so, you may find they tend to get hung up on the upper half of the log, more so on irregularly shaped logs.

It looks like the rails and the diagonal pieces are made from pretty sturdy angle iron. I'll be interested to see if the predrilled pieces can stand up, they look a bit thin to me.

Post some pics of it in action!

Dan

 

[BobL]

I like the "mechanno" look of your mill.

As you are relying on single bolts connections (and the bar) to stop the mill from racking lengthwise, one thing I would recommend for long term use is either extra bolts, or adding a cross (or length) wise diagonal to the mill frame. Relying on the bar to prevent racking will stress the metal surrounds of the bolts connected to the bar and could eventually damage the metal at these points.

Looking forward to seeing it in action.

 

[cruckshank87]

I probably will remove the dogs which would also give me a few more inches of cutting width as well. Hoping the metal holds up, might need to beef it up, we'll see. And Bob, I think I understand what you're saying, although I'm not exactly sure what racking means :monkey: I'll try to shore it up with some more diagonal members. Will definitely posts pics when I get it going, but might be a week or two.

 

[BobL]

.
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And Bob, I think I understand what you're saying, although I'm not exactly sure what racking means :monkey: I'll try to shore it up with some more diagonal members. Will definitely posts pics when I get it going, but might be a week or two.

Racking refers to the sideways distortion of a frame or structure like this.

The reason your mill will tend to do this is because the mill frame is only fixed to itself using single bolts.
What happens during milling is the saw continually slams itself and the bar into the cut which generates a reaction force that will tend to rack the mill (the racking direction will be opposite to what I have shown in the diagram). This will squeeze the mill rails close to the bar which places unnecessary friction onto the mill as well as stressing the bolts attaching the mill to the bar.
Using two bolts instead of one to connect the mill rails to the mill end frames, or a lengthwise diagonal on the millwill reduce this problem.

 

[cruckshank87]

Thank you Bob, excellent diagram!!!:msp_thumbup: I will install some lengthwise diagonal pieces to help shore it up & post some pics afterwards.

 

[glennschumann]

Additional Horizontals

Welcome!

I would add a horizontal (or two) in the areas that I show in this horribly crude editing of your photo. If the guide board you are using to keep your cuts flat is not much longer than your log, these will allow you to "level out" the mill before you engage the saw in the log.

Hope that helps

Schumann
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[cruckshank87]

Welcome!

I would add a horizontal (or two) in the areas that I show in this horribly crude editing of your photo. If the guide board you are using to keep your cuts flat is not much longer than your log, these will allow you to "level out" the mill before you engage the saw in the log.

Hope that helps

Schumann
View attachment 228346

Hi Schumann, if I understand correctly, the bottom of these horizontal sections would be even with the bottom of the rails so as to allow the mill to slide evenly onto the guide board. That way my guide board would not need to extend past the log to the other side rail. I like this idea, now I have to toy with the design part of it!

 

[glennschumann]

Yup!

Yes, you have it exactly! Again, regrets for the crude graphics. This also helps if you decide to cut your second, third etc cuts without the top guide rail, you can just start the mill on the top surface of the now cut log. I don't recommend that for any but the most rough cuts. If you get a little bit of twist, or a dip, rise or some roughness, that gets telegraphed onto the next board, and can be amplified if the gods are working against you. I always put a guide board on top for each cut to keep the smoothest cut, and this also allows for minor corrections as needed.

Hope that is helpful.

Schumann

 

[mad murdock]

simple and straight forward. Can't wait to see how you make out testing it on a log. One question/observation; The hole you drilled in the bar tip, how did you miss the nose sprocket bearing?

 

[BobL]

simple and straight forward. Can't wait to see how you make out testing it on a log. One question/observation; The hole you drilled in the bar tip, how did you miss the nose sprocket bearing?

The hole actually goes through a hardened steel disc which is the inner bearing race. Provided you go thru the middle it is no problem.

 

[cruckshank87]

Drilling hole in nose

The hole actually goes through a hardened steel disc which is the inner bearing race. Provided you go thru the middle it is no problem.

I have searched for and found threads in the past regarding this issue, Bob. You and others have posted a lot of useful info on the topic. I used a bit for hardened steel, lots of cutting oil, and was somewhat successful for a bit and then I ended up work hardening the steel by not maintaining constant cutting at a low enough speed (I think). So then I had to do most of it with a dremel and a few grinding stone attachments. I drilled/grinded a 5/16" hole in the center of the tip.
I've been slammed busy lately, but hopefully will have some time this weekend to work on it. Will definitely let everybody know how it works once it's up and running.