Pattern Maker's Dowels

[Ray H]

I am endeavouring to construct some baseboards for my new layout.

 

I have:

1. taken the two proposed mating ends of adjacent boards

2. clamped them together so that the top edges are flush

3. drilled 2mm pilot holes through both where I want the dowels to be fitted

4. enlarged those holes to 26mm on the mating sides deep enough (plus a little) to accept the dowels

5. enlarged the pilot holes to 9mm

6. screwed the male dowel into position

7. applied epoxy to the rear of the female dowel which I then placed into the relevant recess

8. clamped the two mating surfaces together to allow the epoxy to set

9. tried to separate the two ends so that I could screw the female dowel in place without it moving

10. found that the expoxy has stuck the female dowel to the relevant end but surplus glue has seeped out and also stuck the two dowels together and, thus, the two ends together

 

Luckily, I was quite conservative with the epoxy and have managed to separate the ends and have cleaned the epoxy off the dowels ready to try again.

 

Should I have screwed the female dowel in place and then applied the epoxy to the back of the male dowel or have I gone about things completely wrong and should have . . . . . . .

 

?

[AndrewC]

I find that if you've drilled the pilot holes accurately you can insert a 9mm bit into the hole and use that to align the female dowel plate and screw it in place. You shouldn't need to muck about with glue. Your biggest alignment problem is ensuring the dowels are not in their holes at an angle. As long as the countersunk hole is even you should be ok.

[Ray H]

I used a bench drill for the main holes, only the fixing holes are drilled with a battery drill.

[gordon s]

I agree, there is no need for epoxy at all as the countersunk screws will hold it firmly in place provided you have sufficient thickness to wood to accept 1/2" screws. If not, glue a block in place behind the baseboard frame. Steps 1, 2 and 3 are fine and I then use a Forstner bit to cut the recess on both sides. It doesn't matter which half you fit first, but I fit the female half and then drill out the clearance hole for the male with the female plate in place and use the hole in the female as the guide.

 

As Andrew says, the key is accurate drilling and I would recommend a pillar drill if available, to ensure the holes are perpendicular to the work frames.

[AndrewC]

I did 4 modules for the club layout with dowels a couple of years ago. they have a steel jig and I used one of the member's pillar drill. Absolute perfection in the alignment. When it came time for my own layout I just made a quickie wooden jig to create the pilot holes and then carefully enlarged with a forstner bit. I didn't have the luxury of a pillar drill so I had to do it by hand. They all aligned pretty well but a couple required some fettling. After doing 33 module ends I never ever want to see another one again.

 

 

 

 

edit: added pic

[Ray H]

I think that I may have discovered where I could have done differently.

 

Having used the Forstner bit to cut the recess on both sides individually, I also drilled the 9mm holes individually. I think, perhaps, that I should have clamped the boards together again before opening the holes out to 9mm. That said, I've just checked the males and they're only 8mm and the dowels themselves are 25mm not 26mm.

 

Is the initial 2mm hole too large to ensure that the centre pin of the Forstner bit aligns accurately before the outer part of the bit starts to cut the hole? Could I be applying too much force to the bench drill arm and thus forcing the centre point into the relatively soft plywood slightly out of line rather than allowing the bit to find the centre naturally?

 

One "problem" that I see is that the varying diameter of the three drill bits also affects the length of those bits which means that the table has to be raised and lowered repeatedly. This means that the fence on the false table keeps being re-positioned. Perhaps I should ignore the fence rather than try to use the bit pressed into the hole as the means of attempting to restore it to its former position and not getting that position quite right.

 

Probably down to laziness on my part as I was trying to avoid having to mark the position of the (two) holes on the twelve separate end pieces.

[Donw]

In order to avoid problems marking out I cut strips of 4mm ply to match the baseboard ends clamped two together making sure that one end marked as top was aligned spot on then drilled two holes to suit the dowels. I then fixed the ply strips to the basedboards one either side of the join carefully aligning the top edges. I could then fit the dowels into the holes drilling out clearance where needed. Thus avoiding any need to measure and mark up two matching ends.

Don

[Ray H]

Don

 

I like that idea - I hasten to add that the baseboards are still in their component piece stage at present which I had hoped would make the job of fitting the dowels easier.

 

I had another try yesterday and was immediately thwarted by the fact that of the two packets of dowels that I had open - both were from the same supplier - one would fit a 25mm recess and the other (just) wouldn't. Likewise, one would accommodate an 8mm drill through the centre hole of the female, the other (just) wouldn't (and a 7.5mm drill was far too loose).

 

That's part of my problem. Alignment can't be guaranteed as soon as there's any play in either the recess or the centre hole.

[RedgateModels]

Do you not use the "pip" on the reverse of the male part to mark where to drill for the female half?

[Ray H]

This is where I start to get confused - which, I'll admit, isn't too difficult for me!

 

I've drilled a 2mm pilot hole through both (9mm ply) baseboard ends. I've then (as I thought) used this to centre the forstner bit to drill the recess for the dowels. Finally I've used either an 8mm or 9mm drill to open up the pilot hole to accept the male part of the relative dowel. However, because I've had to use a 26mm bit to open out the recess for the dowel which is only a shade over 25mm in diameter, the dowel is no longer a precise fit in the recess so I'm at a loss as to how to ensure that one lines up with the other. Another idea I have had is to screw the male dowel face down onto the reverse side of one of the ends and drill pilot fixing holes right through both ends using the male's fixing holes as a guide.

 

Would the following work?

 

Clamp/screw the two ends together, outer faces outermost. Drill the pilot hole through both ends. Use the Forstner bit to open out and produce the recesses on the outer faces then enlarge the pilot hole to 8 or 8.5mm. Finally, using the female dowel (in its recess) as a template, drill fixing pilot holes right through both end pieces. Finally, separate the two ends, fix the dowels in place and . . . . (Do the same again as often as requried).

 

Previously, I've been clamping the two pieces together face side in and only drilling the 2mm pilot hole with the two ends clamped. All other holes have been drilled with the two ends separated.

[meil]

I had another try yesterday and was immediately thwarted by the fact that of the two packets of dowels that I had open - both were from the same supplier - one would fit a 25mm recess and the other (just) wouldn't. Likewise, one would accommodate an 8mm drill through the centre hole of the female, the other (just) wouldn't (and a 7.5mm drill was far too loose).

 

 

 

 

Seems to me you have been sold a 25mm dowel and a 1" dowel.

 

Clamp the two ends together. Drill your 2mm pilot hole ensuring the drill is at right angles to the end.

 

Separate the two ends and form the 25mm recesses in both ends using your Forstner bit.

 

Put the dowels in the holes and ensuring the dowels are a firm fit in the 25mm recess fix them with screws.

 

When fixed drill the clearance hole for the male dowel.

 

I suggest you practise forming the 25mm recesses in some off-cuts.

[Ray H]

All but the (screw) fixing holes have been drilled using a bench drill.

 

What seems to be happening is that the twist bit that I'm using to drill the 8mm hole is wandering off centre.

 

It looks like I need to speak to the supplier and see what he says about swapping the apparently inch dowels for 25mm ones.

 

I shall have another try tomorrow with some scrap and see how I get on.

[gordon s]

Unless I'm misunderstanding, the 8mm hole is to clear the male. If you fit the female first, it will then act as a guide to drill the 8mm hole and ensure it is central. As Ian suggested earlier, you can then use the female to align the male and the spike on the back will give you the centre mark once you squeeze the frames together.

[Ray H]

Update.

 

I've been in touch with the supplier and he agrees that it is possible that I have a mix of metric and imperial dowels. He has agreed to swap old for new and refund my postage.

 

As I've only opened two packets - apparently one of each, and unaware of the differences - I suspect that part of the problem is that I've unintentionally mixed the pairs. This could explain some of my problems.

 

As I mentioned earlier, I'll experiment again tomorrow and report back. In the meantime thanks for all the suggestions.

[Ray H]

I discovered that I'd got two metric and four imperial pairs when I came to return the imperial ones this morning so I was stuck with just two pair in the short term to make up all the relevant ends. I decided to use those as templates so that all I needed to do when the metric replacements arrive is to screw them in place.

 

I didn't start making my first set of ends until late morning whereupon I immediately hit a further snag which I think suggests that instead of sending back the imperial set that I'd opened (and used), I'd inadvertently kept that set (along with a previously unused metric set) and sent the used metric set back with the three unused imperial sets. It was my own fault for trying to be a bit clever and avoid opening the packaging to check each set. Instead I relied on minor differences in labelling and packaging between imperial and metric sets and must have got confused and slipped the wrong set into the package of returns by mistake. Luckily I managed to overcome the problem but don't ask how in case the Mr. Elfandsafety is watching.

 

Anyway, by the end of the afternoon and with a few minor adjustments to the earlier of today's attempts I've now produced four of the six mating pairs of ends - the missing two pairs await a decision by me about the width of one baseboard. I've also got the first baseboard under construction but a lack of suitable length clamps (and a somewhat full diary) means that assembly of each board will be slightly protracted.

 

I found Gordon's most recent suggestion worked the best for me and I managed to get the holes neatly in line without any further effort once I resisted the urge to press too hard on the point on the rear of the male dowels when using it to mark the centre point of the hole on the male dowel board.

 

Many thanks for all comments and suggestions.