LumberJocks

Advice on fixing my bad joinery

  • Advertise with us

« back to Woodworking Skill Share forum

Forum topic by groland posted 02-20-2009 01:01 AM 1462 views 0 times favorited 9 replies Add to Favorites Watch
View groland's profile

groland

152 posts in 2875 days


02-20-2009 01:01 AM

I am making some rather large mortise and tenon joints in red oak. My first joint came out way too loose, the part with the tenon just falls out. I know this will result in an unacceptably weak joint. What can I do? Would it make sense to buy a small amount of veneer, laminate it to each side of the tenon and try refitting? Other thoughts?

Many thanks,

George Roland


9 replies so far

View HokieMojo's profile

HokieMojo

2103 posts in 3191 days


#1 posted 02-20-2009 01:16 AM

my solution on one project was to just use lots of glue. Don’t follow my lead. is the piece too large or complex to just recut? you may be able to make your own piece of vener out of scrap lumber. I can get a pretty thin slice (althrough a lot of waste) just using a table saw. I feed the main board through like normal and set the fence so there would be a sliver of “waste”. That waste could possibly by used for what you want. I’d be curious what others suggest.

View teenagewoodworker's profile

teenagewoodworker

2727 posts in 3231 days


#2 posted 02-20-2009 01:30 AM

ya just glue some little pieces of veneer on each side. just make sure to orient the grain in the same direction

View Mark Shymanski's profile

Mark Shymanski

5314 posts in 3175 days


#3 posted 02-20-2009 01:32 AM

And do them a bit oversize so that you can then sneak up by planing the tenon down to the correct dimension….at least that is what I have read that you are supposed to do if you make that kind of error…

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

View shack's profile

shack

114 posts in 3538 days


#4 posted 02-20-2009 02:58 AM

Is it close enough too cut a slot in the center and wedge it

-- JohnShackleford,North Carolina

View Scott Bryan's profile

Scott Bryan

27251 posts in 3285 days


#5 posted 02-20-2009 03:09 AM

Another alternative to using veneer, if the fit is not too bad, is to fit a strip from a brown paper sack around the tenon and glue it up. Let the glue dry and, if the mortise fit is satisfactory, go ahead and glue it up. If it is tight then just sand the tenon until you get a good fit.

-- Challenges are what make life interesting; overcoming them is what makes life meaningful- Joshua Marine

View tenontim's profile

tenontim

2131 posts in 3207 days


#6 posted 02-20-2009 03:53 AM

I usually save the thin slices that are left from cutting tenons with my tenon jig, just for this purpose. I glue them on the unde size tenon, which will make them too thick, then re-cut the tenon to the correct size. The veneer thing will work also, if you have some on hand.

View groland's profile

groland

152 posts in 2875 days


#7 posted 02-20-2009 05:21 AM

Thank you, gents, for these great suggestions. This gives me confidence to go forth with a fix in mind.

I have only made about four of the twelve mortise and tenon joints I must prepare on this project. The third and forth ones seemed to shape up better requiring a firm hand push to seat but without a need for hammering—or much hammering anyway! I’m getting better and faster at the same time. Time is such an interesting companion here.

I am learning to sharpen my chisels, use pencil marks as a guide for paring away waste, using a small gauge recommended by folks on this forum to test for flat, square surfaces on my mortises, planing with a shoulder plane to refine the fit, etc. Much more to learn but it is very gratifying to see progress, even if it is modest.

Fortunately, this is a hobby for me—I am making things for my own use, so I do not have to produce rapidly. In that regard, I have had to learn to work slowly. I need to go very slowly, relish every sliver of wood removed and try the fit once more. If I start tensing up, it’s time to stop and return another day when Im in a better frame of mind.

Good evening,

George Roland

View Karson's profile

Karson

35035 posts in 3863 days


#8 posted 02-20-2009 05:56 AM

Glad you got some great solutions. I was going to say. Make a thin slide of wood, glue it on and then trim it to size again.

-- I've been blessed with a father who liked to tinker in wood, and a wife who lets me tinker in wood. Southern Delaware soon moving to Virginia karsonwm@gmail.com †

View lcurrent's profile

lcurrent

123 posts in 3278 days


#9 posted 09-18-2009 12:20 AM

Using loose tenons or floating tenons stops all the problems started at the mortise machine #1 They take a good amount of pressure to cut the square hole # 2 The holes need to be worked on with a chisel to make sure you get a good fit #3 I found it very hard to make 10 mortises the same #4 Chisels need to be kept sharp #5 When every thing is done right the bottom of the mortise still looks like crap

Now for the tenons #1 You have to allow extra on each end to go in the mortise
  1. 2 Stock thickness must be exact because if not the that is the difference in the tenon
  2. 3 Back to the chisel to tune them in

Now loose tenons #1 Mill and cut all stock to final size mark the center of all mortises in rail stile or whatever cut all the mortises to the size and length and depth #2 Mill the tenon stock Bull nose one side cut to width then bull nose the nemaining side cut just shy of double depth make as many to assemble the entire piece if you are happy with it You can glue up stages

Larry

-- lcurrent ( It's not a mistake till you run out of wood )

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com