Baseboard rigidity

User avatar
Julian Roberts
Posts: 1388
Joined: Sat Jan 09, 2010 11:33 pm

Baseboard rigidity

Postby Julian Roberts » Sun Jun 19, 2022 1:38 pm

20+ years ago I set out to make baseboards Barry Norman style. Not following any particular instructions I glued some 150mm wide strips of 6mm ply round the edges of a 4mm ply rectangle. I found it was very floppy. Simply on the spur of the moment I tried glueing a diagonal piece from one corner to the other, also 150mm wide (or deep). The weak floppy baseboard became rigid and strong, and it was the basis of several more, making a 00 layout that was this year just as strong and stable as when it was made.

For my Kyle layout I tried making the larger of the two baseboards required without a diagonal, as I normally see done.
20220317_124056.jpg


Result - floppy baseboard.

The addition of a diagonal makes it completely rigid.

20220328_095002.jpg


For the second board I made it the same way as the very first one all those years ago, simply to show what happens.

Screenshot_20220613-232410_Gallery.jpg






This baseboard is now being kitted out with supports for the surface.
20220619_144525.jpg

I often see or hear it said that baseboard rigidity requires thick wood, say 12mm ply. My conclusion is that this is not necessary.
You do not have the required permissions to view the files attached to this post.

Stephan.wintner
Posts: 109
Joined: Sun Mar 15, 2020 11:04 pm

Re: Baseboard rigidity

Postby Stephan.wintner » Sun Jun 19, 2022 3:35 pm

Speaking as an engineer, you are correct. Rigidity does not require thick stock - triangulation is very effective.

I've built one module using 6mm ply, and then next will be 4 if i can find suitable stock. (The number of plies in the plywood is important.)

A brief glance at any number of latticework structures - bridges, train shed roofs, etc - will reveal many triangles and very few, if any, quadrilaterals in the latticework. There's a reason.

Aircraft employ a semi monocoque structure, where the skins of the wing or fuselage serves the function of the triangulation. The top skin of typical model railroad modules does as well. But the open bottom could do with some triangulation.

Thanks for your post - the photos and videos are very good explanation.

Stephan

User avatar
Julian Roberts
Posts: 1388
Joined: Sat Jan 09, 2010 11:33 pm

Re: Baseboard rigidity

Postby Julian Roberts » Mon Jun 20, 2022 9:57 am

Thanks Stephan

Something else I found worked was that beams can "fly" where there is stuff immediately below the baseboard surface. To keep the beam rigidity I glued on another narrow pit of ply so it became L or T shaped. Zooming in you can see I did that on my first Kyle baseboard where it flies over (i.e. beneath) the point motors area - it's a very narrow offcut. In fact most of the beam is "flying" and it does the job just fine. Looks quite a bit more elegant than the second board! This is the Templot drawing showing where the diagonal goes.
You do not have the required permissions to view the files attached to this post.

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Mon Jun 20, 2022 12:00 pm

Another approach to the diagonal triangulation is to use a cable (or rod) in tension. The cable/rod can be very light (think of the loads applied to a bicycle spoke in tension). The main consideration is adequately anchoring it in the corners so it cannot pull out or distort the corners. There also needs to be a way to apply and adjust the tension. That can be done with standard items - try your local sailing club supplier.

davebradwell
Posts: 1173
Joined: Fri Jan 18, 2019 3:48 pm

Re: Baseboard rigidity

Postby davebradwell » Mon Jun 20, 2022 5:50 pm

......or you could put a flange around the bottom as long as the corners are joined well. Best treated as a bottom skin with a large hole in it. We used to make an instrument optical base like this and it was very stable....in metal, of course.

DaveB

Terry Bendall
Forum Team
Posts: 2416
Joined: Sun Jul 27, 2008 7:46 am

Re: Baseboard rigidity

Postby Terry Bendall » Mon Jun 20, 2022 7:52 pm

I don't claim to be an engineer but I know a litle bit about making things in wood and metal. To be successful this method requires the plywood to be straight on the edges and the edge needs to be in contact with the top along its whole length. The ends need to exactly at 90 degress to the edges and be a close fit. When assembling I would use PVA woodworking glue and hold things with clamps until the glue dries. A glue gun is useful tool but on long joints the glue goes cold quickly and may not held sufficiently. The corner blocks as shown in some of Julian's pictures are useful since they provide additional surface area for the glue.

If I was doing the job I would fix the corner blocks with PVA glue and panel pins to one piece and then apply glue to the other and clamp until dry. Where possible I would fit some panel pins or wood screws as well. I would want to use more vertical supports to stop the top sagging between the cross members - probably supports at 300mm spacing.

Stephan.wintner wrote:I've built one module using 6mm ply, and then next will be 4 if i can find suitable stock. (The number of plies in the plywood is important.)


A decent timber merchant (not a DIY store) should have 4mm thick birch plywood which is much better than plywood made from one of the types of timber found in some tropical countries - sometimes a timber called meranti is used. Birch plywood has the layers (the veneers) of equal thickness, whereas plywood made from some tropical timbers does not. Normally plywood of that thickness will have three veneers.

Provided it is used correctly, PVA glue is very strong but to be successful the joints do need clamping and for a job like this a lot of clamps would be needed. Sometimes when I have taken things apart that have been glued the wood will split rather then the glue give way but that is usually on thicker pieces of timber. For applications such as fixing the ends to the sides and the pockets for the legs I would use screws through into the blocks. Glue by itself will work but may fail over time. Belts and braces, :) but then I prefet thicker playwood all round. each to his or her own of course.

Terry Bendall

Stephan.wintner
Posts: 109
Joined: Sun Mar 15, 2020 11:04 pm

Re: Baseboard rigidity

Postby Stephan.wintner » Tue Jun 21, 2022 6:13 am

Terry, I'd agree with just about all of that except your choice of thicker plywood - and as you say, to each his own, there is definitely more than one way to build a sound baseboard. David Bradwells suggestion of a flange round the bottom is another effective way to approach it.

(I found a table saw gave me straight cuts when i built mine, but a track saw or laser cutter should serve as well. I'd have doubts about a circular saw or bandsaw, but maybe.)

(And I'm sorry if my "speaking as an engineer" came off as arrogant.)

Stephan

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Tue Jun 21, 2022 9:20 am

Terry Bendall wrote:.....

A decent timber merchant (not a DIY store) should have 4mm thick birch plywood which is much better than plywood made from one of the types of timber found in some tropical countries - sometimes a timber called meranti is used. Birch plywood has the layers (the veneers) of equal thickness, whereas plywood made from some tropical timbers does not. Normally plywood of that thickness will have three veneers.



Depends where you live... I've not yet found a timber merchant who would normally stock what I'd call decent quality birch ply(*).

And, there is a war in Ukraine with the UK imposing sanctions on Russian goods. Russia was a major supplier of birch ply. Don't expect to get stuff easily even at a good timber merchant for a while.



(* Glasgow, Edinburgh, and Newcastle are inside that search area. But I may have missed the magic key supplier in my searches. Best I've found are suppliers into laser-cutting services. )


- Nigel

User avatar
Julian Roberts
Posts: 1388
Joined: Sat Jan 09, 2010 11:33 pm

Re: Baseboard rigidity

Postby Julian Roberts » Tue Jun 21, 2022 10:43 am

Thanks - I can see the slots for the legs need further reinforcement.

I have got the ply from a supplier that cuts very accurately. So I get the main rectangle cut to size, the rest of the sheet is cut into perfectly straight strips of various widths. 150mm for the sides, which protects the point motors - not sure that depth is necessary for the rigidity. As you say Terry the glueing must make the strips flush along the edge of the baseboard top which thus is flat. The hot glue gun isn't perfect, but if held for 10 mins the join sets. Photos show clamps in operation, I've forgotten what the four were doing here.

The boards weigh 4kg each so far.
You do not have the required permissions to view the files attached to this post.

User avatar
Julian Roberts
Posts: 1388
Joined: Sat Jan 09, 2010 11:33 pm

Re: Baseboard rigidity

Postby Julian Roberts » Tue Jun 21, 2022 10:50 am

Can't seem to upload more than 2 photos per post this morning. Two boards joined together.
You do not have the required permissions to view the files attached to this post.

User avatar
Winander
Posts: 842
Joined: Thu Mar 20, 2014 12:19 pm

Re: Baseboard rigidity

Postby Winander » Tue Jun 21, 2022 12:26 pm

nigelcliffe wrote:decent quality birch ply

Nigel,
I am a bit confused by this remark. Birch ply comes in different grades defined by different amounts of repaired imperfections (mainly knots). Is this what you refer to above as 'quality'?

I have seen Latvian birch ply listed alongside Russian, but on the two sites I saw that, the 3mm I was seeking was Russian. IIRC at least 6mm and up was additionally listed as Latvian, so the supply problem may not be as bad as expected, although it is still going to be affected.
Richard Hodgson
Organiser Scalefour Virtual Group. Our meeting invitation is here.

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Tue Jun 21, 2022 1:02 pm

Winander wrote:
nigelcliffe wrote:decent quality birch ply

Nigel,
I am a bit confused by this remark. Birch ply comes in different grades defined by different amounts of repaired imperfections (mainly knots). Is this what you refer to above as 'quality'?


I've often approached suppliers seeking birch ply, and what is offered as "birch ply" is birch outer facing, and the inner layers are something else (typically red, slightly spongy, and often with lots of filler).

To me, quality birch ply is thin layers of birch throughout, typically alternates light/dark/light. I have made baseboards, machine tool frameworks, and furniture from it. I find it is difficult to source.


Yes, there are grades covering the number of knots in the surface, that's secondary to the basic structure of the ply.


- Nigel

Alan Turner
Posts: 643
Joined: Sun Jul 20, 2008 4:24 pm

Re: Baseboard rigidity

Postby Alan Turner » Tue Jun 21, 2022 2:25 pm

nigelcliffe wrote:
Winander wrote:
nigelcliffe wrote:decent quality birch ply


To me, quality birch ply is thin layers of birch throughout, typically alternates light/dark/light. I have made baseboards, machine tool frameworks, and furniture from it. I find it is difficult to source.


- Nigel


You can get it from here: https://www.woodshopdirect.co.uk/blog/w ... op-direct/

Good service and they cut to exactly your dimensions.

Good delivery too.

regards

Alan

Terry Bendall
Forum Team
Posts: 2416
Joined: Sun Jul 27, 2008 7:46 am

Re: Baseboard rigidity

Postby Terry Bendall » Tue Jun 21, 2022 4:01 pm

nigelcliffe wrote:Depends where you live...


Yes of course although most large towns normally have a suitable supplier.

Birch Plywood comes in different grades as below:

"Baltic, Russian and other European birch plywood faces are graded by the letters B (best), BB, CP and C (worst) for both the face and the back. These plywoods usually have a consistent void-free core of the same species as the face. Generally B/BB is the best grade that is available"

The web site https://www.trada.co.uk/media/3819/birc ... 013_lr.pdf gives some more information about the specifications for grades of birch plywood.

The timber and sheet material supplier James Latham Ltd have a very informative web site about all sorts of timber based materials. See
https://www.lathamtimber.co.uk/products ... ch-plywood They are more of a wholesale supplier but when I used to make thr sleepers for the Society I got the plywood from them.

Stephan.wintner wrote:I found a table saw gave me straight cuts when i built mine, but a track saw or laser cutter should serve as well. I'd have doubts about a circular saw or bandsaw, but maybe.


Yes a table saw or circular saw bench will do a good job.. I usually use a portable electic saw and then plane the edges straight but then I am old fashioned, :)

Stephan.wintner wrote:(And I'm sorry if my "speaking as an engineer" came off as arrogant.)


Not at all :) You are giving people the benefit of your experience as I was from a different perspective.

Terry Bendall

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Tue Jun 21, 2022 5:09 pm

Terry Bendall wrote:
nigelcliffe wrote:Depends where you live...


Yes of course although most large towns normally have a suitable supplier.

...


In all seriousness, its not "most large towns". Unless I'm really bad at finding them.
When I lived in East Anglia, there used to be one supplier in Norwich until they closed. Then I couldn't find anything in Suffolk or Norfolk, though clearly the up-market boat builders had sources. Now I live in Kelso (south east Scotland) and I've searched and can't find anything in the whole of Scottish Borders or Northumberland, or the Edinburgh area.

( Yes, I have Latham's on my possible sources list ).


- Nigel

davebradwell
Posts: 1173
Joined: Fri Jan 18, 2019 3:48 pm

Re: Baseboard rigidity

Postby davebradwell » Tue Jun 21, 2022 5:54 pm

Some years ago I helped a friend cut some strips for baseboard members. We used the edge of a sheet of the material as a guide for a portable hand held circular saw and cut off 8ft lengths dead straight with no need to trim or plane. It mimics the guided saws used by suppliers. I think you'd have to be very skilled to use a saw bench and fence to get consistent straight cuts and a curve would try and develop which would get worse with each subsequent cut.

DaveB

Chris Pendlenton
Posts: 54
Joined: Wed Dec 30, 2009 7:14 pm

Re: Baseboard rigidity

Postby Chris Pendlenton » Tue Jun 21, 2022 10:26 pm

Nigel,
I have been building quite a number of ply baseboards and have sourced my 9 and 12mm birch ply from J Richardsons of Penrith. A wee bit south of the Border but not too far, and a grand run from Kelso. They have a website and are obliging folk. I don't know the official quality code, nor the country of origin but it has even layers of alternatively coloured birch, all absolutely flat, light years away from the rubbish you get from DIY stores, with their undulating layers,fillers of sweepings and voids. A side benefit of using the best ply is the utility of the offcuts. I'd say I've followed Terry's procedures, and his preference for heavier material and have found screwing directly into the edges of the 12mm ply is perfectly ok if pilot holes are drilled though I do have a good number of corner blocks as well. I think another virtue of thicker material is reduced noise.

Chris P

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Wed Jun 22, 2022 7:17 am

Chris Pendlenton wrote:Nigel,
I have been building quite a number of ply baseboards and have sourced my 9 and 12mm birch ply from J Richardsons of Penrith.


Thanks Chris, I'll record them in my supplier list. I agree with the remainder of your comments on using ply of decent quality, I've done similar with jointing, pilot holes, etc..

- Nigel

Terry Bendall
Forum Team
Posts: 2416
Joined: Sun Jul 27, 2008 7:46 am

Re: Baseboard rigidity

Postby Terry Bendall » Wed Jun 22, 2022 7:35 am

Some further work information on plywood grades sourced from the internet may be useful

"Plywood bonds and specifications
Plywood bonds – EN314-2
Plywoods are produced using bonds. The types of bonds used are based on whether the plywood is for use in dry, humid or exterior conditions.

The BS EN 314-2 Plywood bonding quality requirements define three classes on the basis of test requirements that the plywood bond must meet:

Class 1 is dry interior conditions EN636-1
Class 2 is humid interior conditions where there may be doem dampness and limited outdor exposure to moisture as might happen during construction. EN636-2
Class 3 is exterior use. EN636-3

These classes are determined by laboratory tests in which different plywood boards are subjected to simulated weather conditions. The integrity of the plywood bonds after the tests will determine it’s bond class.
Plywood specifications – EN636
Following on from the EN314-2 tests, plywood boards are required to comply with one of the three performance classes within EN636 for use in construction. This takes into account the quality of the bond and the durability of the timber species used.

"
nigelcliffe wrote:Now I live in Kelso (south east Scotland) and I've searched and can't find anything in the whole of Scottish Borders or Northumberland, or the Edinburgh area.


Well that surprises me Nigel. Out of interest I did a web search and found the following which look like they may be useful. You may of course tried them already.

Andersons Ltd.
https://www.andersonslimited.co.uk/shop ... n-showroom
Timber world
https://www.timberworld.co.uk/sco/branch-finder/
MKM Ltd
https://www.mkmbs.co.uk/search/plywood
St Andrews timber supplies
https://www.standrewstimbersupplies.co. ... materials/

Somtimes a supplier will be able to get plywood in as a special order if they dio not keep it in stock

Terry Bendall

nigelcliffe
Posts: 747
Joined: Mon Jul 21, 2008 8:31 am

Re: Baseboard rigidity

Postby nigelcliffe » Wed Jun 22, 2022 9:49 am

Terry Bendall wrote:
"
nigelcliffe wrote:Now I live in Kelso (south east Scotland) and I've searched and can't find anything in the whole of Scottish Borders or Northumberland, or the Edinburgh area.


Well that surprises me Nigel. Out of interest I did a web search and found the following which look like they may be useful. You may of course tried them already.

Andersons Ltd.
https://www.andersonslimited.co.uk/shop ... n-showroom
Timber world
https://www.timberworld.co.uk/sco/branch-finder/
MKM Ltd
https://www.mkmbs.co.uk/search/plywood
St Andrews timber supplies
https://www.standrewstimbersupplies.co. ... materials/

Somtimes a supplier will be able to get plywood in as a special order if they dio not keep it in stock

Terry Bendall


Thanks, two of those listed, Dumfries and St Andrews, are a long way away (both over 2 hours driving each way).
MKM are very helpful (and I use them) but only have the birch faced with fat red filling type. The manager there said he could enquire about other types from their suppliers, but unless I would have to order multiple sheets in one go, as that's how stuff is delivered to them.
Which leaves Timber World/Rembrand as a new one to try, who have a branch in Selkirk.


- Nigel

BrockleyAndrew
Posts: 174
Joined: Wed Jan 30, 2013 12:18 pm

Re: Baseboard rigidity

Postby BrockleyAndrew » Sat Jun 25, 2022 9:55 pm

Just watching a documentary on the Mosquito bomber and its wooden hi-tech design 1930/40s wise.

User avatar
Simon_S
Posts: 134
Joined: Wed Aug 06, 2008 7:32 am

Re: Baseboard rigidity

Postby Simon_S » Mon Jun 27, 2022 12:56 pm

What benefits does the top quality birch ply offer? I haven't had any problems working with DIY store ply and wonder if "better is the enemy of good-enough" applies here.

Stephan.wintner
Posts: 109
Joined: Sun Mar 15, 2020 11:04 pm

Re: Baseboard rigidity

Postby Stephan.wintner » Tue Jun 28, 2022 1:20 am

At least some thin plywood is noticeably more flexible in one direction than the other, because of the (uneven) ply distribution. In general, for a given thickness, the more plies the better, the resulting sheet is sturdier and stronger. But if the facing sheet grain runs in the long direction of the piece, the difference may be small. It's more important on thinner material.

Stephan

User avatar
Julian Roberts
Posts: 1388
Joined: Sat Jan 09, 2010 11:33 pm

Re: Baseboard rigidity

Postby Julian Roberts » Sun Jan 29, 2023 9:32 pm

I'm not quite sure if this will make sense as I haven't fully read up what was written here previously.

It was kindly pointed out to me that the baseboards required more strength where the legs were to slide in. This was done, but I took no pictures of the process. Pictures below may show the overall effect.

I realised the boards would require a completely rigid support so that no twist or other forces were put on them from below, other than the supporting one. So the separate legs end up being just as heavy as the boards, but each is quite portable.

So this is what came out of the process. The main board has four legs. Two of them have a folding arrangement attached:

20220929_165643.jpg


They slide into the board thus, attach with a hook, and then fold out

20220929_170109.jpg


The other pair of legs slides into place attaching with a hook, engage with and bolting to the bracing arrangement.

20220929_170326.jpg


The second board has just two legs.

20221003_172404.jpg


They similarly slide in, hook up, and the folding part engages with a bolt. The arrangement looks like this

20221003_172720.jpg


Together thus

20221003_173232 (1).jpg


I'm not showing every single detail. The main point is that the boards are pretty quick to erect and dismantle, individual parts are easily carried, and there is total rigidity in the fixings so that I can for example pull the coupled pair of baseboards along the floor without any strain on them. Apologies I'm not spending more time editing the pictures to eliminate the ahem surrounding chaos. :o
You do not have the required permissions to view the files attached to this post.

User avatar
Jol Wilkinson
Posts: 1111
Joined: Mon Jul 21, 2008 7:39 pm

Re: Baseboard rigidity

Postby Jol Wilkinson » Mon Jan 30, 2023 8:13 am

Julian,

a practical approach but perhaps a little over complex.

The attached photo shows both the original London Road layout in the background and the additional "extension" under construction which converted it from a terminus to a through station. The extension section in the foreground replaced the RH end terminus board.

In either case a "foundation" board (the ones with two sets of legs, a pair of braces and lower stretchers) provided enough rigidity for the other boards which were "piggy backed" on to the foundation board. Each of the other boards has its own braced pair of legs.

The one major difference to your concept appears to be the thickness of the wood. The legs were from two sections laminated together, the outer section extending up to fit into a slot in the baseboard. All joints were screwed and glued and the resulting ensemble proved strong and rigid enough for exhibition purposes. As this included viewers leaning on the fiddle yard surrounds at either end (until I made them full height) it was clearly up to the job.

AC hall set up 1.jpg
You do not have the required permissions to view the files attached to this post.


Return to “Baseboards and Carpentry”

Who is online

Users browsing this forum: ClaudeBot and 0 guests