Sash

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Bill Ebner

New member
I have an opportunity to make a 6 over 6 and a 9 over 6 window for a period house in my area. Although I've done a little such work in furniture, I don't have a strong background in sash work. Would anyone care to comment about estimating the time involved in making one window?

Thanks,

Bill
 
Bill,

Are you using only hand tools, and if power tools, which ones do you own ?


I would expect that if you have a shaper or router table, that will have a tremendous impact on the manhours required.

Karl
 
Bill,

Here is my suggestion:

Build the sash in your mind; start with the rough sawn stock you intend to use and walk though the steps to get rip and plane toget  finished raw  stock, and then the time to do each step like the joints and the moulded edges and rebates. Make yourself a list of the steps, and associate your best guess of your manhours for each. It should be pretty detailed, and be sure to think of the molded shape of the edges that slide in something. Some recommend that you build a simple jig in which to assemble the sash on your benchtop ot table; allow time for that.  Allow time for a dry assembly at each step, and don't forget the matters of priming,painting, and glazing which could take as long as building the wood frame.  I can imagine breaking the job into as many as 50 steps when you are doing this for the first time.

Next add the hours together and multiply by a factor for unknowns.  I would start with 20-30%, but it might end up being 100% the first time you do this, and almost never less than 15% even for the most experienced workman doing repeat work.

Let us know what you come up with and then individuals can give you feedback on the various steps.

There are some useful videos on You Tube about building window sashes to help you make sure you have every step included in your mental process.

If you do the project, keep track of the actual hours agaist your list to help in future estimates.

BTW, if you are tempted not to do this much thinking I can only say I did shop estimating in a former life, and any thing short of actually figuring out how you wil build  it is high risk of a low estimate.

Karl


 
I can see that Karl speaks from experience!

I have built a number of replacement window sashes for two period homes I have owned.

I cannot comment how long it will take you to build your sash. I will say the first time I did this it took a while because I had to learn a number of things.

Here are a few points you may want to consider:

I have always used a router to make the "sticking" (Rails/Stiles and Mullions). But after the initial stock preparation phase, I don't find power tools are much of a help. What is *very*time consuming is the glazing of the glass, all the priming, installation, caulking, and final painting. I also pre-prime and caulk all joints on the frame before assembly to maximize weather proof-ness.

I have found using the router bits to do the coping (where the mullions meet the rails/stiles for instance) to be only a small time saver over just simply doing it  by hand using traditional techniques. In fact, I pretty much prefer to do them by hand because it saves all that ditzy setup w/ the router, w/ I find very error prone. The only time I bother to setup the "coping" bit is if I have to do lots of mullions.

I have found open mortise and tenons cut on a bandsaw to be the fastest/best solution for where the rails meet the stiles on the window frame. Mullions have to go into deep mortise holes.

If you intend to hollow out the mortises by hand, then you should pay close attention to how long that will take since it will probably take a significant portion of the overall time. After trying to do it a number of different ways, I found that a hollow chisel mortiser (simple attachment on my drill press w/ quality bits) was the best approach for reproducing traditional mill work efficiently.

I have learned (the hard way) to always make a full sized drawing of the mullioned sashes(s), and use that to size and locate everything accurately. Given that I've made a number of windows at this point, I get away w/ a story stick. But I found it very confusing the first time I made a window. For the first window I made I tried to do it w/o plans and I think literally spent 1/2 the time puzzling out the joints and what the length of each piece should be. That's NOT the way to do it!

I have found it best to use 2 hour two part Epoxy to glue everything together. The main reason it works best is that it will fill and completely seal everything. I believe this gives you the best chance that it will survive the weather. I pay particular attention where the glazing will go. The glazing eventually cracks and leaks so I want to make sure the window will stand up to leaks under the glazing for a long time so that it wont rot while it waits for someone to get around to fixing it. That's where the Epoxy shines. It produces a waterproof seal at all the joint interfaces. I also prime the rabbet the glass slips into *before* glazing. Another precaution against the inevitable when the glazing starts to leak.

Weatherstripping the window is an important consideration. I could speak volumes about that, but will consider it out of scope.

Typically, making the window frame takes only a small fraction of the time it takes to make the sashes. But milling the matching period trim, oh well, that can be another big job in itself. I assume you won't be doing that.

How will the sashes stay open / closed. Will it include sash weights or is it a casement style? Making something that moves is more difficult than making something stationary. So you will need to factor some extra time for that.

Whew - lots more I could say but I'll show some mercy and stop here. Now, to try and help you w/ your question:

I recently made 4 replacement sashes for two windows in my Victorian house. These particular windows had no mullions. I have done sash work about 12-14 times at this point. The time broke down as follows

1 hour to make drawings and plan (remember, I've made a number of these at this point, so most everything I need is already in hand)

2-3 hours stock prep and to mill it into "sticking" (I already had the lumber on hand). I used a router setup to create the profiles along the lengths of the rails/stiles.

2 hours to make the open tenons where the rails/stiles meet.

1-2 hours to glue all the sashes together. For some  reason this always takes longer than I think it should

2 hours to measure and procure glass.

6 hours to clean up the sashes the next day after the glue dries and to trim them to the right size so that they will operate properly in the out of square opening in my home. This also included time to make the slots where the sash cords go, etc... Lots of running up/down steps etc... Not sure how applicable all this is to your task at hand.

1 hour for first coat of oil primer on ALL sides of everything, especially the rabbets where the glazing will go. "Hang" the sashes up on something to dry. Requires overnight dry.

2+ hours install glass and glazing for four large panes. If there were mullions and small panes, then I would estimate 20 minutes / pane. This is *highly* dependent on how skilled you are at this.

Let the windows sit a few days so that the glazing will set a bit.

1/2 hour prime the glazing. Again, I had no mullions to work around. Each window pane adds considerable effort.

1/2 hour finish coat inside of windows. Clean brush, put windows aside and wait to dry.

1/2 hour finish coat outside of windows w/ Exterior paint. Clean brush and wait to dry.

2-3 hours to install, touch up paint, install hardware, wash windows, etc.... Maybe even longer. Forgot really.


What I really wanted to point out here is that *most* of the time is waiting for stuff to dry. The actual woodwork  is really only a small part of the overall task, and the work has to proceed in small steps w/ long wait times in between. Hope this helps,

JB
 
Let me comment on JBs very valuable inputs.

He states he has made sash about 12-14 times, and his estimate to do one works out to about  20 hours give or take to do one using his tools and methods. If I work that backwards using an 80% learning curve, I would guess the first try probably took him about 45 manhours.  Just for yucks, I had guessed 40 hours off the top of my head before he provided hard data, but I would NEVER go with a guess if the answer matters.

Note that his estimate of glazing and painting is about 1/3 of the total manhours.

Karl
 
Bill, 20 hours per is a pretty good estimate for a 6 x 6. A little more for the 9 x 6.  If I can be of assistance at all, let me know. I make this by hand quite often. In fact, I just demonstrated sash making at the LN tool show with the SAPFM Ohio River Valley chapter.

Zach
 
Perhaps a dumb question, but does the cope go on the tenoned part or the mortised part (rail = tenoned part; stile = mortised part)?.  It seems pretty obvious to me which way I would instinctively do it, but I saw an article where the copes were on the stiles and couldn't figure out why you'd want to do that.  Seems to me one ought to cope the rails.

JD
 
The stiles get coped to except the rail's molding. We offer a simple layout tool which will also work for cutting cog (Cock)beading for drawer fronts.  

 
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