# WIP — Traditional Screw Veneer Press



## marcus (4 Jan 2013)

This week I've started working in earnest on my new veneer press. It's going to be of the traditional type with lots of hand screws, and I thought I would do a WIP as there's not that much info about this on the web and it will hopefully be useful to someone.

I'm departing from tradition in that I'm basing it on a torsion box. The reason for this is that I don't have space to have the press set up all the time, so need it to easily dismantle, and I don't want to be shimming and adjusting it every time I assemble it. With a torsion box I will know the platen is flat. As an added bonus it will double as a dead flat assembly table, and by drilling a grid of holes on one side I will be able to flip it over to serve as a base for attaching jigs for steam-bending, laminating etc.

I've started by making this torsion box which is the heart of the whole thing. It is 6' by 3' which is bigger than I need right now, but my intention it to be doing larger work with it in the future, and I only want to make a press once!

The skins are 3/4" BB grade birch ply, the core is 5" deep 12mm mdf. Since torsion box stiffness is mostly related to the thickness of the skins and the depth of the core, this should produce something very rigid. I used mositure resistant mdf, on the basis that it is better quality generally, and most of the things I will be using the press for involve a certain amount of water and heat. 

The long edges of the box need to be drilled to take steel rod which will support the cross bars for the hand screws. In order to support these rods I need thick core sections at the edges. I laminated them up from 3 pieces of 18mm mdf.







I then jointed and planed to width all the mdf for the core as accurately as possible, and drilled eight 22mm holes down each of the laminated pieces for the steel rods.

I needed a flat reference to assemble the box on. I used two saw horses, which I screwed to the floor. To them I attached OSB fins levelled with a spirit level, and laid four lengths of 4x2, accurately jointed and thicknessed on top. With the benefit of hindsight it would have been better to have made the fins out of something thicker or attached them differently — they bent a tiny bit with the weight of the box, and I had to wedge them at the ends to compensate.






On this platform I laid the bottom skin, which is the one drilled with holes for attaching jigs. The holes are 6mm at 50mm centres and I had them CNC drilled because I thought I would struggle to get so many spot on, and they need to be very accurate to work well. I got the company that drilled them to also drill the 2' offcut from the end of the board with the same pattern, so I can use it in future to help set out holes on formers etc that will exactly mate up with the holes on the skin (to which they will then be secured with 6mm metal pins).






I had this bottom skin cut 4mm oversize, so I could easily use it as a guide to set out and assemble the core on. The top skin, which was be glued to the core second, was 20mm over size.

The usual recommendation is to use a nail or staple gun to assemble the core. I don't have either, and also the sides were too thick to nail through, and screws seemed like too much fuss, so I used housings to locate and secure the cross pieces.






The lengthwise core pieces were cut and placed individually between the widthwise ones and secured with hot melt adhesive, again because I don't have a nail gun. There's no question that a nail gun would have been a more convenient choice if I had one. Still the glue held the pieces in well enough, and the strength comes from the bond between the core and the skins — the bond within the core doesn't matter very much. The spacing of the core is not quite regular as I needed to dodge the holes in the bottom skin and the holes for the rods at the edges.

Then it was a question of making sure the core was dead flat using a straightedge and spirit level and a handplane. I was quite obsessive about this and took a good hour on each side. obviously there's no going back once the skins are glued on.






I put a polythene dust sheet on top of one of the skins, laid the core on top and did a final check for wind with a spirit level. I then spread glue over the top of the core and laid the other skin on to it. I then secured it to the core with screws (I pre-drilled clearance holes in the skins). The screws are set below the surface and I filled the holes with filler later on.

Once the glue had gone off I flipped the assembly over and drilled through the 22mm holes along the edge and out through the skin, using one of the 2x4 supports to eliminate breakout. The holes are drilled through the second skin using the same procedure once it is glued on. I was a bit paranoid I would forget to drill through the first skin before glueing on the second which would have left me in a real fix, but fortunately I remembered!

I did the drilling like this (ie drilling the core first, then drilling through the skins once assembled) so that I could take advantage of the accuracy of the pillar drill, which would have been impossible once the box is glued up.






When only one skin is attached the structure is not very stiff at all. However as soon as the second skin is glued on (using the same procedure as for the first) it immediately becomes enormously rigid. 

Then it was just a question of trimming round the slightly oversized skins with a router using a straight bit with a bearing, chamfering the edges, and generally neatening things up.






I was originally planning to paint the skins with epoxy paint, but had visions of the paint getting into the small holes on the drilled side and being a nightmare to clean out. So I have decided just to give it a couple of coats of wiped varnish/oil and to wax the platen side now and then.

The holes at each end are handles to help with moving it about. It's quite heavy.

I haven't made a torsion box before, but having done one I'm quite impressed. If I ever need a new workbench I will definitely consider using torsion box construction.

So that's a start. There is still the press assembly and the legs/frame to make. And 32 hand-screws to fit....


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## riclepp (4 Jan 2013)

Sounds a really interesting project,the only snag is; I cannot see any of the wip pictures


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## marcus (4 Jan 2013)

Sorry, bit of technical difficulty. Now fixed I hope....


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## AndyT (4 Jan 2013)

I was impressed by the amount of thought and planning that must have gone into this, and then the careful attention to detail. Then I looked at your website and it all seems to fit into place! Do please give us the whole story and show us it in use as well.


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## riclepp (5 Jan 2013)

Very nice, I do hope you continue the wip


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## Tierney (6 Jan 2013)

Very interesting, I'm thinking of doing a bit of veneering soon, so will be watching this with interest!

DT


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## marcus (7 Jan 2013)

Thanks for the interest! I've some more bits and bobs to be delivered in the next few days, so should be more coming soon I hope....


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## marcus (18 Jan 2013)

I've been spending the last few evenings making the steel rods for the cross bars. This involved threading 20mm steel rod at each end to make 16 assemblies with wing nuts, washers and shaft collars. 






They were made from 20mm steel rod. The holes they go through are 22mm, as I wasn't convinced I would get the holes all exactly perpendicular to the face of the torsion box. Having the rods a little bit smaller means they locate by reference to the face of the box rather than relative to the hole.

I threaded the rods by hand which was hard work. It would probably have been better to have out-sourced this job to a proper engineer! I also realised that it would have been better to have used tube rather than rod. The rods are much heavier than they need to be and tube would have been more than strong enough.

The bottom of the rods is threaded for 5 inches which will enable me to adjust their height. I used standard shaft collars as stops for the rods, which seemed simplest given my lack of metal working skills. Most of them were the cheap ones which have a grub screw that tightens onto the shaft:






I found that that the grub screws were marking the rod, to the extent that the marks then interfered with the movement of the collar when I was changing its position (which I will need to do now and again when setting the height of the rods). I tried to source some brass tipped grub screws to solve this, but couldn't find any in the right size, so I just filed the sharp cone off the bottom of each screw and put a tiny bit of brass sheet under each one. Seems to work OK.

4 of the rods are longer and will be used to attach two trestles to the bottom of the press as well as supporting the cross bar above. On these I used split shaft collars as stops because the trestles will be held on with nuts tightened with a spanner (instead of wing nuts like the rest of them) and so will need to resist a larger tightening force. I only used these split collars for these four because they're a lot more expensive, and the collars on the other rods are really just stops which won't be stressed very much — when the press is tightened the stress will be taken by the wing nuts.






And speaking of the trestles that's the next bit I'm making — next week hope.


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## Tierney (19 Jan 2013)

You're a glutton for punishment, I would have bought threaded rod. Good idea to attach the trestles with the rod.

DT


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## marcus (19 Jan 2013)

> You're a glutton for punishment, I would have bought threaded rod.



I was tempted! I didn't for two reasons — 1) because when veneering one is often working fast and it seemed to me that threaded rod is likely to do more damage to a component if given a careless knock; 2) aesthetics — which is a bit silly with workshop equipment, but I'm putting so much effort and resources into this thing anyway I didn't want to compromise!


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## deema (19 Jan 2013)

Looks brilliant, well done


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## Tierney (20 Jan 2013)

marcus":2h17yr5g said:


> > You're a glutton for punishment, I would have bought threaded rod.
> 
> 
> 
> I was tempted! I didn't for two reasons — 1) because when veneering one is often working fast and it seemed to me that threaded rod is likely to do more damage to a component if given a careless knock!



Good point, didn't think about the risk of damage.

DT


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## mn pete (21 Jan 2013)

Wow. That's a serious press. This is mine!


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## marcus (22 Jan 2013)

> This is mine!


Damn I should have thought of that  

I've managed to get the trestles done in the last two days. I used 3 x 4 ash. I was ordering a load of ash anyway for the cross bars, so I decided to make the trestles from the same stuff.






I cut a load of 'quick and dirty' twin mortise and tenons,






chamfered the edges of each component with a router using chamfer cutter and bearing, then sanded to P180,






then glued up with a bit of help from the end vise on my bench (picture taken just before I drove in the tenon wedges). 

You can see that the holes at each end of the top rail are deeply countersunk (again with router and chamfer bit with bearing); this is to help locate the steel rods that go through them when assembling the press.






Then once the glue had gone off I planed the tenons flush and screwed some double locking casters to the bottom rail. These look a bit flimsy but have a max loading of 100KG each which should be enough. The double locking bit is important — when you apply the brake the wheel locks and also the spindle is prevented from rotating which makes the whole thing a lot more solid for working. Without doubt the secret of working in a small workshop is good wheels!






Then a coat of oil and put it together:






The plan seems to be working! One of the useful things about a torsion box for this sort of thing is that it is stiff and stable enough for you to be able to just bolt two trestles to it — no need for longitudinal rails. Makes it all very simple to take apart and put together, and also more compact to store when it is disassembled.






Tomorrow I hope to get the cross bars done, then it's almost there.


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## marcus (7 Feb 2013)

Sorry it's been a while, I got distracted by other jobs and had to solve a few teething problems but have now finished it!

I realised that I had made an error of judgment with my original plan to have the trestles secured using the same steel rods that hold the beams (see previous post). It seemed a good idea when I thought it up but was too clever by half. It made changing the configuration of the press a PITA. It also meant that when the torsion box was being used as an assembly table there was no way to attach the trestles without having the head of a bolt protruding from the table top. This was far from ideal. I therefore abandoned my original plan and drilled some separate holes between the others with which to secure the trestles. I inset the bolt heads so that the top is now completely unobstructed when in assembly table mode:











I then started work on the press-screw beams, which are made from 3" x 4" ash. I relieved them a bit at each end using the bandsaw and the RAS. 






This was for neatness, to help keep the wing nuts that secure the beams to the rods away from the press-screw handles. This should become clear in the later pictures....

I neatened up with a block plane:






Then I drilled holes to take the rods and the press screws. I chamfered the edges of the beams with a router using a chamfer bit with bearing, and sanded to p180.






The sockets for the press screws are driven into 1 1/8" holes with a mallet and block of wood. This feels a bit 'edgy' as they are not that substantial and take a lot of force to drive in. I was worried one might break, but they were fine.






Then they are secured with screws in the indents on the lugs at either side.







I had a local fabricator make me some steel beams to spread the load from the press screws (which is considerable) across the underside of the torsion box and add further to the stiffness of the structure. They are made of 80mm x 40mm steel box section (4mm thick). The holes are generously oversized to make assembly easier and compensate for any inaccuracies in the holes I drilled in the torsion box. In an ideal world 'I' beams would have been better still, but it would not have been possible to drill the holes where they were needed.











Here it is assembled at last!






And here it is with the aluminium plates for heating. This is the biggest reason for making the press - to do traditional hide glue veneering with heated plates. I have three large ones at 2' by 3' which covers the entire surface of the press. There are also some smaller ones which I already had that fit in the oven; these will be simpler for smaller workpieces.






Here's the press in action with a small test piece. You may remember that in the first post I showed four 2" x 4" battens which I used as a base for assembling the torsion box. These I now cut in half producing 8 spreaders, one for each beam. These help to even out the pressure of the screws, and protect the workpiece from the point loads the screws produce.






One of the main intentions behind the design was to have something that would be very adaptable. This has been born out in practice, and I'm well pleased with the possibilities it has opened up, not just for veneering but for assembly and clamping. 

I expect that for a lot of the time the press will sit in the corner of the workshop with only five of the beams attached. By a bit of serendipity my saw horses fit neatly underneath, which saves a bit of space elsewhere:






This setup gives me an extra surface in the workshop for assembly (or just for putting things on!) while also having enough press space available for the majority of the veneering I need to do. In this configuration the assembly space is also ideal for laying out veneer and substrate before they go in the press. Then you just slide them under the beams and tighten the screws. It makes for a very easy and natural process, really enjoyable to do. 

If I need to do a large bit of veneering I can pull the press out and attach the extra beams. If I want a large, dead flat assembly table then I take all the beams off. If I need the floor space for something else I can disassemble the whole thing and put it away: it takes up surprisingly little space leaned against the wall.

So there it is, finished at last, thanks for watching!


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## AndyT (8 Feb 2013)

I can't find the picture where you put the sheet of slate on the top, with the green baize and six pockets! ;-)

It does look really sturdy and useful.


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## JonnyD (8 Feb 2013)

Looks a great end result enjoyed the thread. I hope to use some torsion boxes for some workbench tops soon and have picked up some tips. It hasn't converted me to hide glue for veneering though  

Cheers

Jon


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## Tierney (8 Feb 2013)

Great thread, thanks for posting.

DT


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## marcus (9 Feb 2013)

Thanks chaps,



> I can't find the picture where you put the sheet of slate on the top, with the green baize and six pockets!



Should have thought of that — perhaps that should be on the reverse side, so I just flip it over during tea breaks....



> I hope to use some torsion boxes for some workbench tops soon and have picked up some tips.



My top tip — don't do what I did, use a nail gun for the the core!


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## mtr1 (10 Feb 2013)

Good thread, very informative, and good end result. Will you be heating the alu platens with an electric blanket, or have you devised another way? They look very large, or do they just look like that and fit in an oven? I use an electric blanket with a bagpress and use various glues, but have done quite a bit of traditional hammer veneering in the past using hide glues, its very underrated and quick to use.


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## marcus (11 Feb 2013)

I'm going to heat the large plates with a paraffin heater as recommended by Patrick Edwards http://wpatrickedwards.blogspot.co.uk, who seems to know what he's doing! He puts the plates on saw horses puts the heater under them and boxes it in with scraps. Haven't tried it yet though so it's a bit of a step into the unknown.... They need to be quite hot with this method and I don't think a blanket would be powerful enough.

I like hammer veneering, for me the problem is that I'm often using thick veneers, and it gets quite tricky with a hammer once you get over 1mm thick or so. Also for more complicated patterns it's good to be able to assemble the pieces beforehand and put the whole lot into the press together rather than cutting and fitting the veneers in situ....


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## woodaxed (11 Feb 2013)

interesting post although i know nothing about veneering was enjoyable to read with clear pics, I ask thought using paraffin heaters
doesnt sound to safe as i know they give off a lot of water vapour


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## giantbeat (12 Feb 2013)

good lord that is a beautiful piece of kit, so well done!!

i have a decent home made veneer cold press we made for making veneer ply laminations for my day job, its no where near as nice as yours & i never found a source for those press handles, we used thread bar with nuts welded to the top using driver guns to screw them down... i will try and dig out some pictures, its been used most weeks for just over 8 years now

once again, that is an amazing bit of tooling you have made.


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## otisluxton (4 Mar 2013)

marcus":101yckps said:


> Sorry it's been a while, I got distracted by other jobs and had to solve a few teething problems but have now finished it!



Hi Marcus - where did you manage to get your press screws? I have searched high and low for them and cannot seem to find them anywhere but the US - any advice?

Looks great,
Thanks, Otis.


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## dazzer (4 Mar 2013)

otisluxton":2at5jc8q said:


> marcus":2at5jc8q said:
> 
> 
> > Sorry it's been a while, I got distracted by other jobs and had to solve a few teething problems but have now finished it!
> ...




Hi Otis

I had the same problem as you last year when I was looking to buy some veneer press screws - I couldn't find them anywhere or if I did they were really expensive 

I then found some on Amazon - you can find them here at just over £10 ($14:20) http://www.amazon.com/gp/product/B0000DD353/ref=cm_cr_rev_prod_title

I didn't know what to expect as I thought they wouldn't be up to the job but I am really pleased as the press screws are nicely made and quite sturdy

I bought 4 of them and the postage was really cheap for the 4.  

I hope this helps you or anyone else who needs some 

All the best
Dave


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## otisluxton (4 Mar 2013)

Hi Dave,

Thanks alot for the link! Ive just ordered one, so will let you know what I think when i've got it though. I cannot believe there is absolutely no one importing these in to the U.K. I might even make a cider press now I know theyr'e so cheap! The one i've ordered is to make a guitar side bending machine - Looks like the ones ive looked at are using almost identical screws - can't see how they are charging almost £400 for one now I know the press screws are fairly cheap. 

Thanks for the help,
Otis.


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## marcus (4 Mar 2013)

Highland woodworking in the US sell the 12" Jorgensen ones, that are bigger than the ebay ones (which are 12" overall as opposed to 12" shaft), and I think a bit nicer to wind up and down as there is no second handle to get in the way. There are also 18" ones available, or 9".

http://www.highlandwoodworking.com/jorg ... rew12.aspx

If you're shopping around then 'Jorgensen press screw' is a good search term.

Obviously also have to pay shipping, plus uk import tax and VAT. Depends on how much you order but for me I think it worked out at about £25 per screw. 

Agree it's strange no one stocks these in the UK.


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## dazzer (4 Mar 2013)

otisluxton":2eg978l7 said:


> Hi Dave,
> 
> Thanks alot for the link! Ive just ordered one, so will let you know what I think when i've got it though. I cannot believe there is absolutely no one importing these in to the U.K. I might even make a cider press now I know theyr'e so cheap! The one i've ordered is to make a guitar side bending machine - Looks like the ones ive looked at are using almost identical screws - can't see how they are charging almost £400 for one now I know the press screws are fairly cheap.
> 
> ...



Glad to help Otis 

Its nice to see a fellow Luthier  
I bought mine for guitar side bending machine as well  
Do you just build acoustics/classical or do you build electric's as well?
If you don't mind me asking are you building anything at the moment?

All the best
Dave


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## bugbear (5 Mar 2013)

marcus":2qr4arau said:


> The sockets for the press screws are driven into 1 1/8" holes with a mallet and block of wood. This feels a bit 'edgy' as they are not that substantial and take a lot of force to drive in. I was worried one might break, but they were fine.



Too late now, but I'd have used a piece of threaded rod (fine enough to go straight through) and pulled them through from the far side (using suitable washers to spread the load).

Bugbear


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## marcus (5 Mar 2013)

> Too late now, but I'd have used a piece of threaded rod (fine enough to go straight through) and pulled them through from the far side (using suitable washers to spread the load).



Not a bad idea, though I was probably being over-parnoid — I think they're stronger than they look, and driving them in was the approach suggested on the stickers....


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## otisluxton (5 Mar 2013)

dazzer":1q5a034n said:


> Glad to help Otis
> 
> Its nice to see a fellow Luthier
> I bought mine for guitar side bending machine as well
> ...



Ah! Maybe that's the only use for the things apart from actually making veneer presses! - Im totally fed up with using bending irons - they're too inconsistent with their results and simply takes too much time for something that a machine can do whilst I can be doing something more enjoyable! What did you use for your heat lamp bulbs if you don't mind me asking? I've seen these ceramic bulbs that just produce heat and no light which are around 150-250w and was thinking of trying them first? Wondered if you could suggest anything there? Or do you use heat blankets? (another thing that I would have to order from the states)

Im only building acoustic instruments at the moment - mostly guitars and I'm big in to Parlour guitars at the moment so a lot of them. Right now im building a classical parlour guitar pretty much in the style of a Louis Panormo, but with slightly modified bracing - Im using all British, native woods, so there's a lot of experimentation going on with thicknesses and bracing, though its not my first native-wood guitar so its not all new to me. 

How about yourself? I would be interested to hear what you build, and any other projects you are working on? Also, any tips on the side bending machine!

Thanks,
Otis.


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## dazzer (6 Mar 2013)

otisluxton":erz59vs5 said:


> dazzer":erz59vs5 said:
> 
> 
> > Glad to help Otis
> ...



Hi Otis
Nice to hear back from you 

I build acoustics and at the moment I'm building a couple based on the Taylor Grand Auditorium. I have a bending iron which is big enough for Chello's and is ok for touching up sides off the side bender or if I fancy just doing it by hand as I find it relaxing sometimes to do the sides if I'm not in a rush  The side bender I use is with heat blankets. The blankets I bought from a Chinese company which made the to order. I ordered a 36" x 6" 1050watt blanket a 6" x 6" blanket for doing cutaways. The two blankets have built in Thermocouples. The two blankets cost me £90 delivered and were the best value from any supplier I will send you their details through PM

The side bender I have has two veneer screw's one for the waist and another for cutaway!

I've a few more builds to get going soon but need to get these done 

All the best Dave


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## Eric The Viking (10 Mar 2013)

Thank you so much, Marcus, for taking the extra time to write this up. It's been really interesting (just read through it over breakfast!). As a real amateur/novice, I've been wondering about veneering - started reading up about techniques some years ago. It's great to see such a practical design, so well executed.

If I might make a comment, and ask a question: 

I think you're dead right about paraffin heating over electric - those plates are aluminium - electric blankets are notorious for fraying in use and ageing, and to heat a plate you'd be running them much hotter than normal. You _might_ boil them up in a vertical tank. That arrangement might let you do several at once, but they'd probably need small holes drilled near an edge so you could dangle them in the water and pull them out. If they're close to boiling they'd dry in seconds in normal air (at the expense of cooling slightly). 

The other advantage is that the tank might double as a steam source for steam bending. I was wondering how to heat it - possibly the sort of immersion heater used in domestic hot water tanks - long and thin and with a thermostat and a handy, easily sealed flange. If you're going for boiling point though, it would naturally be self-limiting. It couldn't overheat, but it could boil dry!

Do you know what temperature you need - is 95C enough? 

[Later] I've just remembered, incidentally, that RS Components amongst others used to sell stick-on thermometers for checking things like heatsink temperatures in equipment. They come in a range of ranges(!), and some are single-use (they record the all-time maximum reached), but I think some are like normal thermometers and go down as well as up. If you're boiling them you wouldn't need one on every panel, just on a visible edge.[/later]

My question is a real novice one: I noted your neat, CNC-drilled grid of holes. Do you just run long bolts or studding through to hold things down? I assume this is for glue-ups, rather than veneering though.

Thanks once again for posting,

E.

PS: on Press Screws: I see the point about those Amazon twin handled ones being a nuisance. I'm guessing the intention is that you can use a batten for extra leverage, but you might just grind the handle off one side, if it really gets in the way. If you kept the arm it's attached to, you'd keep it almost in balance, so it wouldn't be too bad.


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## custard (11 Mar 2013)

Impressive job, and lots of food for thought. Thanks for posting!


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## marcus (12 Mar 2013)

Thanks Custard!

Eric, Not a bad idea re hot water, though not sure I'd want a tank of boiling water that big in the workshop. Also it still leaves the question of how to heat the water!

I usually heat the plates to 120 degrees in the oven (I've been doing a load this week as it happens but small enough to be able to use my old method of heating several small plates, so still not used the big plates). If they are 120 you have plenty of time to faff around getting everything place and after that there's still enough heat left to get through 2 or 3 mm of veneer.... I have a new plan for heating the big plates but not sure if it will work yet so watch this space!

The idea of the small holes on the back is that they can be used to attach all sorts of clamps, jigs and templates — I can just push a few steel pins through holes in the jigs that match the holes in the table. That's the idea anyway. Should work I hope, but I haven't tried it yet as I haven't got round to sorting out the pins....


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## beech1948 (18 Mar 2014)

Can't see any pictures

Al


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## rspsteve (18 Mar 2014)

me neither , would be nice too.


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## marcus (18 Mar 2014)

I moved the pictures when I was re-doing my website, will try to get them back up soon


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