Dovetail Log Cabin

[fred in montana]

Here are some photos of a cabin I built a couple of years ago. The one we will build during the workshop in June will be a similar size. There are details about the workshop in the services category.

In this first picture you can see the wavy edge. I moved the saw head up and down as I went along cutting the top and bottom edges of the log. This way the chink joints were not all a constant width. I think it looks less manufactured this way.



 

[fred in montana]

 

[Jeff]

Love it.  There is a very nice, and considerably larger dovetail cabin just around the corner from our place. I admire it every time I go by.

[fred in montana]

 

 




 

 

[tule peak timber]

WOW, cute as heck.....Rob

[beenthere]

Looks cozy, and a welcome camp to come back to after a hike or a hunt.

You should treat yourself to a Logrite cant hook to replace the wood handled one shown. You won't regret it, and the 30" model would be real handy for logs around the mill and the cabin build. Just sayin...

[justallan1]

That's my next dream. Possibly a bit bigger.

Allan

[Magicman]

I love it.  A log cabin bunkhouse is in my dreams.  Hopefully these ole bones will allow me to fulfill that dream.  I looked at trees yesterday.

[Peter Drouin]

I like it, But to move the blade up and down to get the [look] Why not use a dull blade, Or did you? :D

[fred in montana]

The idea with moving the blade up and down was to vary the vertical dimension.

[beenthere]

Seems the same effect could be gained by just randomly easing off some of the corners with a draw knife, and not compromise the fit between "logs" with a wavy pattern.

[fred in montana]

I think the draw knife would work too.

[Jeff]

Is there a way to create the dove tails and have the logs flat against each other, with no chinking space?  I'm having to do some serious rethinking on the cabin I want to build due to the building inspectors requirements.  I have about 180 8-9" average diameter 8ft logs on site. I could build conventional horizontal log. I'd like to flatten the logs on two sides with the woodmizer, and use flat foam compressed between them and log screws to hold them together. Can you still do that with a dove tail corner?

[woodworker9]

Is there a way to create the dove tails and have the logs flat against each other, with no chinking space?  I'm having to do some serious rethinking on the cabin I want to build due to the building inspectors requirements.  I have about 180 8-9" average diameter 8ft logs on site. I could build conventional horizontal log. I'd like to flatten the logs on two sides with the woodmizer, and use flat foam compressed between them and log screws to hold them together. Can you still do that with a dove tail corner?

The short answer is "YES", you can.  You just have to be very accurate with your joinery, cutting the dovetails.  A close friend of mine built his cabin this way in Idaho, and he routed spline grooves between each log for a 1" thick spline.  This spline acts as an alignment aid, as well as keeping the "outside" outside.  He insulated between each layer and over the spline with foam rolled insulation.  The cabin is beautiful, and pretty efficient, too.

Being a professional woodworker, and not a log builder, he took his time, and cut the dovetails by hand with a hand saw, not a chainsaw.  I am personally in awe of seeing dovetails cut accurately with a chainsaw.  I do not think of a chainsaw as an accurate joinery tool, but there are those who are great with one.  I'm more of a handtool guy.

Jeff

[1938farmall]

seems like you could save yourself endless heartache by just using a simple "butt & pass" corner with foam & logscrews.

[Jeff]

I totally agree. Problem is I have to conform to materials and methods the county inspector will allow. I would much rather do butt and pass as I understand the joint and it would be much easier for me.

[cbla]

fred in montana that looks amazing!

[Magicman]

Here is a LINK to Fred's website discussing chink gap size.

I mentioned to him in a PM about using ¼" and he said OK.  My plan is to use 6X8 Red Oak.

[fred in montana]

About 25% of my customers build with zero gap. Some even use factory milled logs having a tongue and groove.

When using any dovetail jig, every cut is precise so it works fine.

[fred in montana]

 

  

  

 

[shelbycharger400]

Yes, i know of a jig that clamps to the log, and stops are built in so you dont cut into it. Ill have to do some digging. I cant remember the maker. But it was $300-500, .

[4x4American]

 looks awesome!

[shelbycharger400]

Guess i was way off on $.  Dream dovetail jig .   $800

[fred in montana]

I built mine for about $50 in about 2 hours and have built three cabins with this set.

[Magicman]

If/when I build, it will be with Fred's jigs. 

My first priority is finishing the bedroom on the Cabin Addition, and then hosting a "Chickin Crispin".

[Jeff]

Fred, how uniform do the logs have to be for your jig to work and will it work on two sided logs with the curves on the outside and inside? 

[fred in montana]

If you are planning to have zero gap then the log dimensions have to be very consistent. I prefer a chink joint myself. If the logs are to be chinked then the log dimensions can vary a lot. You could also go with two sided logs (flat on the inside and outside).

If you want the flat sides to be on the top and the bottom and want to use my jig system, you have two options:

1. Cut a third side to make a D log. The jigs need to attach to a flat face. They attach to the side of the log that is the interior face.
2. Instead ofcutting the interior face full length, you could flatten an area about 2 feet long at each of the log. This will be enough space to attach the jig. The two flat areas would need to be in the same plane.This would be a pain to do I think.

[Jeff]

If I cut my logs on three sides, I'm afraid they will fall under the required dimensions to meet code. My logs are mostly 9" or slightly bigger in diameter

[jwilly3879]

Jeff, where is the inspector getting the the required dimensions from? Or is it an energy code thing? Lincoln Logs uses a butt and pass system and they are solid all over. There is also another home company that uses 4x8" timbers for their packages with 4" thick walls.

[D L Bahler]

You can make a gapless/chinkless cabin without having consistent dimensions in the logs. People do it all the time.

'Verzinkter Block' or dovetailed log cabins built in eastern Switzerland and Austria do this all the time with no problem -these being the ancestor of our American dovetailed log cabins which are something of a simplified Austrian style.

The thing is when doing this, you have to figure the sizing and location of the top and bottom of the joint on each log separately.

What I do -I use interlocking corners, but the same idea will work with dovetails- is this:

Starting with a staggered joint, you measure from the point where the top log will come on the bottom log (which is perpendicular) Then you measure the distance from the bottom point up to the top of the bottom log. The center of the slope of your dovetail must come to exactly half of this measurement, then you cut a corresponding joint on the bottom of the adjoining log.

When you do this, you will create a joint that fits tight, and allows your logs to fit tight along their entire length.

This though requires that the top and bottom faces of our logs be milled and planed very flat.

If you don't have very accurate faces, you must instead lay out each wall on the ground with the logs butted against each other as they would be in the wall once assembled. This way, any inconsistencies and deviations from perfection are accounted for.
So now, instead of measuring to the top and bottom of our logs we have to go by reference lines that are chalked down the middle. We go up the walls, transferring information from adjoining walls so that each joint is unique and accurate.

This is how the Swiss have done it for several thousand years. It is, more or less, a method of log scribing. It's done this way even if the logs are planed to super accurate dimensions, as they tend to do, because you should never trust wood to be perfect. 

[Jeff]

I don't want to spend an entire summer trying to learn how to cut joints and probably ruin several logs in the process. I need the kiss method.

[D L Bahler]

In that case, the American appalachian style is the right thing. This is exactly why it exists, being an adaptation of the more complicated European methods to a situation where it was more important to get a house up fast than it was to build a super nice building. Pretty much, they just eliminated the most complicated parts of the process.
It's the rough, rugged pioneer house, and as  such the style has a certain rustic charm.

[D L Bahler]

I recommend the Appalachian method to people who want a good DIY project without having to master a difficult concept, and who don't have the luxury of a lot of time to do it. The trade off is, it will keep you busy down the road with maintenance, adjustment, etc. 

I recommend the European methods for people who can put more time and effort into it (or pay me to do it,  8)) and who want a building that once it's up, you don't have to worry about it any more. The trade off here is, if you are doing it yourself then it is a lot more complicated and you are more likely to make a mistake learning it.

[Roger Nair]

In my area, the Appalachian (with earthen chink) style log house that have survived the best with simple maintenance are the ones that have been sided or brick veneered.

[landscraper]

Jeff could you use a log corner connection like this? 



I drew it with square logs but I think it could be "2 sided" logs (top&bottom milled, sides still round) too.  I got this idea from another post somewhere, the guy mentioned putting a few squared up logs at a time on the deck of his mill and cutting in at 3" so that there would be good consistency in notch height.  It uses a cheater log on the bottom and top courses to finish out the odd 3" interval.  It could be scaled to whatever size logs you are working with.  When I drew it I had 6" square logs in mind for a little hunting cabin in the woods, not a full time residence.  Probably still some chinking involved.

I can't speak to the merits of this type of notch vs another as I've built exactly zero log cabins.  It just looks like a simple system of joining logs at corners. 

[Jeff]

I'm thinking with smallish logs that might not be the strongest for me. Looks to me like lots of places for moisture to lurk though.

[landscraper]

Yeah that's a concern for sure - I think only the dovetailed or coped joints really "shed" water, even butt & pass has a vertical seam that coincides with an inside corner every other course that I wondered if it would be an infiltration point.   Back to sketchup.

[D L Bahler]

Have you considered a passed lap joint, like:


 

It's really quite simple and very fast to do, far less complicated to lay out than a dovetail joint
It also locks the timbers against twisting and creates a tight joint.

Roger,
in Indiana all the log cabins were immediately clad with siding. The pioneers would bring a barrel of nails and a wagon of wood siding with them into the forest, lay up a cabin and put siding on it.
Quite a few of these are still standing today, often surrounded by an expanded structure as the original house was built onto over the years.

They used a modified v-notch that I'm rather fond of, which made a good secure and tight joint.

[fred in montana]

The (half) dovetail jig method is KISS.

Snap a chalkline down the center of the log. Attach jigs to each end, at the correct distance apart.

Saw all of the notches in less than 5 minutes.

Each log in a wall is interchangeable.

When the logs are stacked, the distance from chalkline to chalkline is always a constant. Each chalkline is level.

This is true even if the logs have varying heights or if they are just sawn on the inside and outside face.

[Jeff]

But I need to saw on the top and bottom face to keep my wall thickness up.  If I put my sawn sides in and out, because of my available log size, they become to narrow to meet the code. Doesn't that leave me out?

[fred in montana]

Can you ask them for a variance? It is not a safety issue after all.

[Remle]

I think this is what you are looking for;

Fred, how uniform do the logs have to be for your jig to work and will it work on two sided logs with the curves on the outside and inside?

Here are pictures of a set of jigs that I made last summer to notch and point 2 sided logs. Feel free to copy them if you want.

Point jig


Notch jig


Checking the notch


Cutoff jig


UHMW spacers on chain saw bar



I hope this helps.

[Jeff]

What are the typical costs if a guy was to leave the gaps and chink?

[fred in montana]

I had about $450 in materials for chinking the 11x15 cabin. That was with gaps that average around 2.5 inches. If the gap was kept to 1 inch I think it would have been about $150.

[Magicman]

I am planning for ¼" so my chinking cost should be minimal.

[mrector]

Awesome  cabin Fred!  I like what your doing with your website, I will be ordering plans for a jig. I have a couple questions.  First is when you leave chink gaps, you just screw in ends on dovetail?  Or do you put in some sort of small spacer that chinking would hide so that beams possibly wouldnt sag over time?  Second is did you insulate floor or just ply, then flooring?
Mikey

Ps if I ordered plans I would never accept a refund. But id send in pics.

[fred in montana]

Thanks Mrector. If the span from end to end is long enough that sag is a concern then I put spacers between the logs at midspan. The spacers are hidden behind the chinking.

In this case I just wanted to give extra support to the log supporting the rafters:



 

You could insert spacers between every course where needed.

I normally don't use screws or nails at the notches. They interlock.

I did insulate the floor from underneath.

[Magicman]

I normally don't use screws or nails at the notches. They interlock.

I have been wondering about that.  I understand the interlocking at the corners, but there is nothing tying the roof to the foundation.  Maybe I am just being overly concerned.

[fred in montana]

 Here is one way of accommodating log settlement at doors and windows:





 

[Magicman]

I liked the illustrations on your website: http://logdovetailjig.com/openings.html

[fred in montana]

Thanks for posting that link. I updated it, adding the newer drawing.

Funny- looking at the older drawings, it is hard to believe that it has been almost 20 years since I drew them.

[fred in montana]

Back in 1997:




 

[Magicman]

Marty and I rode and looked at dead Cherrybark Oak trees yesterday.  There are just too many of them to let go to waste, but I gotta finish the Cabin Addition project first.

[justallan1]

My question is if you want a 24' cabin and only have 16' logs can you join them mid wall? Do you just stagger them and pin them? Is there any particular joint that is best?
My plan would be to saw "D" logs and to build 16x24 with a loft.
Thanks

[D L Bahler]

If you have a chinking gap between log courses, you can't do that.
However, if logs are stacked tight and courses rest atop each other, you can use shorter lengths

The log courses should be pegged together every 2 or 3 feet for strength, even if you have full length logs. Then, you can stagger shorter length logs throughout.

You should have a peg on either side of the splice in the logs above and below to reinforce this joint.

You can use a simple butt joint. I use a butt joint with a spline for both reinforcing the joint and stopping airflow. The spline is also inserted into the log course above and below. This way, my splice joints in my walls are quite strong.

Another way is just to have an upright post in the middle of the wall into which the log ends are set.  This is a very fast way to make longer lengths out of short logs. I also think it is a more attractive approach personally.

[justallan1]

Thank you.

[fred in montana]

You can still splice logs even if you have a chinking gap. Here is one way to do it. You could do this with a D log too.

 

[justallan1]

Thank you.
@fred in montana do you have or know of any place to get a set of building codes and requirements on materials used for the state of Montana or a good place to start. I can ask or figure out how to do most things in life, but dealing with county and state government is a whole new animal.
What books or sites do you guys recommend on a start to finish log cabin?
I've played with the idea of building one and right now have access to most of what I need so am starting to get serious on the idea.

[D L Bahler]

If you can find a copy of the Craft of Log Building by Hermann Phlepps, that's a great book.
It's not an instructional booklet but rather a survey of different European techniques but it will do great things to help you understand the unique requirements and problems one is faced when building log houses.
It will also open you up to an incredibly broad range of techniques and different solutions to the same problems.

[justallan1]

Very cool. Thank you.

[bama20a]

Greeting Fred: Was wondering? The cabin you built in the 1st set of pics- what type of stain or sealer did you use? Sure like the looks of it.Mark,,,,,

[fred in montana]

Not sure about the codes everywhere in the state but I would suggest checking with the county.

As for the stain, there is a technique to that I have described on this page:

http://logdovetailjig.com/11x15build-4.html

[PA_Walnut]

Very interesting thread! If you have larger logs, should one box the heart and use the centers or can you cut multiples from a single log?

[kantuckid]

PA Walnut- when I built my home in 1979-80 (from an even aged stand of CCC planted SYP) I specked the logs at 6" thick, 2 natural sides, 8.5" small end/12" large end. That yields some narrow boards as off cuts but obviously includes the heart which is not an issue now or then. I know a guy locally who did a large A-frame using big yellow poplar roof beams and remember him being displeased with the amount of large cracks to the heart in his home.
A local company sells and builds EWP log homes which are made in the "hewed look" what with larger rectangular cross sectioned cants and I have seen those homes after some years and very few cracks that would matter.
This time around on a smaller cabin, I'm using self sawed, "D" logs, 6" thick and have Fred's plans and will be making my jigs when the weather moderates a bit! I will definitely go for multiple "D" logs on larger trees and smaller one try for two if they get my width spec of ~8". Some of the smaller trees may saw into the first run which will be 6x7" to allow for slabs to cover the floor system and that first run.

It's been too cold to heat my shop of recent or saw outside. CALL ME A WUSS? :'(
  Todays weather for central FL-in the 70's! We leave mid month for some bicycle weather, my hands are chapped and need a break.

[red]

Fred just posted a new video on his YouTube channel On Beaver Creek