Safe routing of muntin & mullions - help

[Steven Golick]

I have been lurking for a while on SMC, and have learned much. Thanks to all. I have a basic safety question which perhaps someone might be able to answer.

I am making a divided light door (out of 3/4"oak stock)for an entertainment unit. I have just purchased a whiteside 6003 rail and stile bit set, and in the cataolg it says that by the slot cutters together (offset) and the bearings together, you can cut the profile for the glass doors (p28 of the catalog). I think I understand the procedure in connection with the rails and stiles.

What I am not sure of is how to safely route the muntins and mullions. Given that the stock will be much thinner than the rails and stiles, and after cutting one side, there is risk of not being able to hold the blank, I am considering taking an extra piece of oak, routing the mating profile and using it as a backer board.

If this is the safest way of doing this, I would also appreciate any experience on how to attach the blank with mated profile to the muntins/mullions while routing (or is friction sufficient?).

(in case it matters for the responses, I am using a PC 7518 mounted on the right side wing of a Delta unisaw, an Excalibur fence modified to accept dust collection for the router on top, and a jointech digital lift (with housing and dc on bottom, and an infinity coping sled to make the coping cuts)

Many thank in advance.

Steven

[Ray Knight]

I have just gotten started on this. I have just repaired an original 1815-1830 set of sashs, and gearing up to reproduce a set of 15 new windows. On the originals, the muntin end have tenons, that are mortised into the side and top rails, and amazingly enough into the vertical muntins (I may be getting some of my terminology wrong. My first try I just used friction and glue and pin nail. Amazingly enough the originals were tenoned and pegged and not glued at all, and lasted about 180 years. I am using a coping bit (that does the reverse of only the curved relief part, leaving the rectangular center part, the other side is relieved with saw or dado, leaving a 1/4 in thick tenon, the mortise of which is done with a power mortise machine. I was orignally going to pin nail and glue only, but the more I got into, the more I wanted to do it right. The only problem is that most window sash router bit sets do full reverse cuts, and don't have the bit that will cope only the profile, but remove that part that would be the tenon. I just did some drawings of what I need to have just the coping part, and sent them for quote to get what will be a 3 bit window sash set. Ray Knight - new to all of this, but having a ball.

[Daniel Rabinovitz]

A very simplified answer - - -
Use an extra piece of wood on the "goes into" and some of it extending past the "goes out of" part of the bit set.
Clamp the extra piece of wood to the table on both ends.

Use a push stick to get between the "piece of wood" and the fence to push your muntins/mullons through.
Daniel

[Bill Hylton]

The key to safely routing sash bars is to make a pusher to hold the narrow strips when you rout the second edge.

To make a pusher, I prefer use a 3"- to 4"-wide block of stock that's the same thickness and length as the longest sash bar. Using the cope bit, rout one long edge of the block. A sticked piece will nest snugly into the cut. To secure the workpiece for a cut, tack a small scrap of 1/4" plywood to the butt end of the pusher, so it juts beyond the coped edge about 1/2".

To make the sash bars, start with a wide piece of the working stock, crosscut it to final length, then cope both ends. Rout the sticking profile along both edges. Rip the edges from the blank, creating the first two half-completed sash bars. Repeat the process until you have the number of sash bars you need.

Now, one by one, tuck the bars into the pusher and rout the second edge.

The book Bill Hylton's Frame & Panel Magic has a chapter on making windows and glazed doors, and it has a sketch of this type of pusher and photos of it in use.

Bill

[Bill Hylton]

Ray,

I guess I'm somewhat impaired in terms of visualizing what you want the cope cutter to produce. You may find some useful info in the windows and glazed doors chapter of Frame & Panel Magic. Infinity Tool, CMT, and quite a few other bit vendors have sash bit sets that have a cope bit that cuts only the negative of the sticking's profile, be it an ogee, a quarter-round, or whatever. Also, check out Amana Tool's website (www.amanatool.com). Their catalog shows several individual bits and bit sets that may meet your needs.

Good luck,

Bill

[Charles McCracken]

The only problem is that most window sash router bit sets do full reverse cuts, and don't have the bit that will cope only the profile, but remove that part that would be the tenon.

You mean like this?:

[Steven Golick]

Many thanks for the replies.

It seems that one way is to make a second fence (Daniel's suggestion) so that the muntins/mullions are pushed between the main fence and the parallel secondary fence with a push stick.

The second way is Bill's suggestion of taking a 3 or 4 inch wide scrap, routing it with the negative of the muntin/mullion, and using a scrap at the end to act as a push.

I assume using feather boards (and of course a push stick) in the second technique will add some degree of safety. I like the suggestion of having a negative, as it should eliminate the possibility of any twisting of the work piece.

Many thanks for the input. I really appreciate it.

Steven

[frank shic]

steven, i made my upper kitchen cabinet doors with false divided lights using mullions several years ago. the mullion milling process probably took the LONGEST since i screwd up at least two batches trying to figure out how to get them to fit correctly on the door and with each other. your effort will be rewarded with some of the most BEAUTIFUL cabinet doors you've laid eyes on!

[Ray Knight]

Charles McCracken posted a picture of the type of bit that I was speaking of as "coping bit". The CMT sash window set has the pictured type bit as the negative, most of the others have a full contour negative, which doesn't allow you to leave the end sticking out to do a tenon. The contour I need for my 1813 windows are for sashs only 1.1 inch thick, with muntins only 5/8 wide, and I have found no commercially available bits that have the contour I need, and the right size, and that give me a full negative and what I am calling (and charles showed) a coping bit. Believe me I tryed (week and a half on the internet, reviewed 6 catalogs)I guess I am getting a bit compulsvie on my first major sash building project, but have committed to reproducing my one original sash as completely as I can. My second prototypes are right there constructionally, now just waiting for the bits to make it the right size with the right contour. Thanks for the input. I'll try to post a picture when I get the first one done. Ray Knight

[Josiah Bartlett]

Ray, It sounds like you have a good excuse to either buy a shaper and get some fully custom knives made, or go full neanderthal and use or make a set of mullion planes.

Post some pictures of those sashes, will you?

I'm glad to hear you aren't just ripping them out and putting in vinyl.

[John Lucas]

This is one of several jigs I made to do what you want to do and do it safely.

This is where story starts: http://www.woodshopdemos.com/cmt-sa1.htm

[Steven Golick]

Looks like a great project. Thanks for posting the description and the pics on the web. This was very helpful.

I was confused by one item. You said that the bit height didn't change as you changed between the two bits. I am confused by that. How did you realign the bits. I assume you are not pushing the bits all the way into the collet (most people leave about 1/4 inch or so). Did you use a set up block to realign each time you changed bits so the profiles would match?

Thanks again

Steven

[Ray Knight]

I am still working on gearing up to do eighteen of the 9 over 6 sash windows for our 1820s house. Restoring this house was to be done in time for my retirement. My son pointed out my pace was so slow I would die before I get it done. Bottom line he convinced me to let him buy it and we are restoring it together. My initial job is to rebuild one rotten original window (done, gorgeous, learned a lot) and then repro 18 more. I originally was just going to do reverse router bit cut on end of muntins and glue/pin nail together. After doing the original, I now feel obliged tdo do through tenon/mortise for all the joints, as original. Believe it or not, those original windows were not glued, tenoned and pinned, but not glued.
So with the tenons the bit requirement changed. But I had followed the discussion of how to safely and accurately rout the ends of the thin muntins. I had previously found the wonderfull picture series listed above, and made one of the muntin containing/holding jigs he suggested. But have now tryed a different method. Rather than rout and form each long piece, cut to length and then rout the end. I have cut the wide stock to correct length, routed the end of the safe square larger board, then routed and cut the strips in shorter pieces. Rather than hold with the reverse piece to safely rout, you can clamp the reverse cut piece to the router table, and push each piece through with a push stick. Looks like this may be how I do the volume work on these repros. I have now figured out at least 2 ways to do each joint. Now figuring out which will be easier and more consistent to do the volume. Thanks for all the interest and help. This is all kind of new to me, but sure is fun. Ray

[Steven Golick]

Ray, that sounds like a good system, provided the friction from the mating pieces is not too high.

Well, I finally got my bits from Whiteside, and got into the shop tonight. First step was to check to see if I could make a simple frame out of rail and stiles with the bits (before getting on to the muntins and mullions). I am pleased to report that it worked like a charm. I did waste one small piece of scrap learning how to set up the bits, but after than, it was a easy as falling off a log. The bits cut through the 3/4 oak like a hot knife through butter. Everything was square and tight.

I used a combination of the suggestions by setting up secondary parallel fence (off set from the main fence by the width of the stock) to route the inside edges of the rails and stiles. I used a coping sled for the coping cuts on the rails, with a piece of scrap as a backing board for tear out (there was none). Worked like a charm.

OK, I admit it, I did rush a bit (kid in the candy shop syndrome), and the joints are out maybe 1/64, but that would be easy to sand out. Next time I will be a bit more careful aligning the copes to the template block that I made, and will also (of course) use an extra piece of stock for (scrap) fitting. But I must say, I am very very happy with the Whiteside rail and stile bits.

This weekend I will start on the muntins and mullions. Can't wait!

Many thanks for everyone's input. It has been very helpful.

Steven

[glenn bradley]

This is one of several jigs I made to do what you want to do and do it safely.

This is where story starts: http://www.woodshopdemos.com/cmt-sa1.htm

I'm with John on this one.