# Material for Jigs?



## Geofract (19 Feb 2015)

Hello,

I see on you tube that, many people make jigs for their TS/Routers with 18mm Plywood (Birch I think?).

I wonder if there are cheaper materials I can use, such as external hardwood plywood. Or should I aim for Birch ply. Perhaps birch ply is more dimensionally stable, and preferred for that reason?

Aside from Hardwood (which I imagine won't be cheaper), are there other wood materials worth using?


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## marcros (19 Feb 2015)

mdf is a suitable alternative to birch ply- ideally MRMDF


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## condeesteso (19 Feb 2015)

Personally I'd say mdf is generally better than any ply variant, more homogeneous and easier to machine details in if necessary (slots, profiles etc etc). Other favourites are some plastics - UHDPE is widely used (ultra high density polyethylene) and is easy to get in part sheets; delron is excellent, I've used corian before but it takes the edge off tools. Rutlands used to do a jig-making pack of screws, T-bolts, knobs etc (they probably still do it), a very handy thing to have around along with a matching length of ali T-slot extrusion.


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## mouppe (19 Feb 2015)

Scraps are cheapest of all!


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## DennisCA (19 Feb 2015)

I've used MDF to make jigs but I won't be touching that stuff again. PLywood all the way for me. I use baltic birch but of a lower B/BB grade.


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## Graham Orm (19 Feb 2015)

Type 'plastic sheet into ebay, there's masses of stuff. My last jigs were from leftovers from my saw/router table. It's in melamine covered 18mm MDF. Looks good but has to be edged....or not. I think it was about £25 for an 8x4 sheet. I was lucky, there's a supplier local, you may have to travel.


EDIT: If it's for the box joint jig I'd use ply.


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## Geofract (19 Feb 2015)

Thank you for all the replies, much appreciated.

I had planned to make a small TS sled to start, though I'm not sure MDF is ideal for that, since I think it might warp with time. But yes, MDF could be ideal for other things. Melamine faced is a good idea too me thinks!


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## Willy (19 Feb 2015)

Personally I think it depends on:


How long you expect it to last
Will it be used again?; and if so:
How often you will use it

No point in using high-quality materials if you're going to use it once, or just now and then.


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## Graham Orm (19 Feb 2015)

Geofract":w3gx9x11 said:


> Thank you for all the replies, much appreciated.
> 
> I had planned to make a small TS sled to start, though I'm not sure MDF is ideal for that, since I think it might warp with time. But yes, MDF could be ideal for other things. Melamine faced is a good idea too me thinks!



MDF won't warp unless it's in an extremely damp area. That's one of it's advantages over solid wood. It's downside is that it won't hold a screw very well.

MDF comes in many grades and types. Red is for fire protection Green is moisture proof, there are others as well. The green is ideal for workshop stuff. Make sure you wear a proper mask, not a paper one. Keep it on until the job's done and you've swept up and dusted yourself off. The dust is carcinogenic.


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## whittler1507 (19 Feb 2015)

How the heck do you post a new topic with tapatalk?


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## deema (19 Feb 2015)

One material I find cheap, stable for jigs with a nice slippy surface is conti board. Not good for lots of repetitive work as the surface will abrade (no worse than either MDF or ply). However, for small batches / occasional use its excellent stuff.


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## Baldhead (19 Feb 2015)

Steve Maskery designs and makes jigs, why not PM him for advice? If I remember correctly he uses MDF, mind you its a long time since I watched one of his DVD's so I could be wrong!

Baldhead


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## Geofract (20 Feb 2015)

Thank you all, lots for me to think about.

I went to my local timber yard today, and the exterior 18mm Malaysian ply they have looked quite good, though I don't know if it suffers with voids.

Not liking the idea of carcinogenic MDF particularly, but might just have to live with it and stump up for a decent face mask.


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## paulrockliffe (20 Feb 2015)

The masks aren't too expensive and a proper mask is much nicer to wear than the disposable ones.

If you're using MDF you can over come any screwing issues by using bolts and tapping threads into the MDF, works great. Is especially useful if you want to make anything adjustable as things can be bolted on and off, or moved along a threaded rod etc.


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## lurker (20 Feb 2015)

What makes you think mdf is a carcinogen?


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## condeesteso (20 Feb 2015)

I believe mdf contains small amounts of formaldehyde, which is currently classified as 'suspected of causing cancer'. Hasn't formaldehyde also been blamed for causing gender inversion in some river fish? (just recall reading it somewhere).


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## porker (20 Feb 2015)

I recently read up on the hazards from the MRMDF I bought from the data sheet on the website as I had also heard previously rumours about carcinogens and specifically formaldehyde. It appears that when identifying the ingredients there are "no materials identified for this purpose as specified in section 5(3) of ‘The Chemicals (Hazard Information and Packaging for Supply) Regulations 2002" and they don't use this in my board and that where it is used in boards, it is emitted in very small quantities. (Norbord Caberwood MDF)

It appears that they use a non hazardous binder and the main danger is the wood dust that it can emit (which carries its own risks). 

I use extraction on my TS55 and a mask and must admit I use it a fair but albeit for DIY projects.


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## Graham Orm (20 Feb 2015)

condeesteso":2jmizh0h said:


> I believe mdf contains small amounts of formaldehyde, which is currently classified as 'suspected of causing cancer'. Hasn't formaldehyde also been blamed for causing gender inversion in some river fish? (just recall reading it somewhere).



What he said.


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## lurker (20 Feb 2015)

Your info is 10 -20 years old or American!
MDF legally sold in the UK has been clear for a long while

There is of course the dust hazard and mdf kicks up a fine ( respirable) dust.
But it is no worse than any wood dust of the same size.

Porker offers good advice.

Just a bit of trivia : did you know that coffee is classified as carcinogenic?
Particularly hazardous is any dry particles from fresh ground coffee


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## dejaa (20 Feb 2015)

Because it contains formaldehyde which is considered a carcinogen. However EU manufactured MDF should contain levels below that considered harmful. Some boards may also contain a percentage of hardwood, the dust from which is more harmful.
remember, it's the dust you dont see that's the most dangerous so always wear an appropriate grade mask


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## Graham Orm (21 Feb 2015)

lurker":3463al0t said:


> Your info is 10 -20 years old or American!
> MDF legally sold in the UK has been clear for a long while
> 
> There is of course the dust hazard and mdf kicks up a fine ( respirable) dust.
> ...



Fair enough, thanks for the info. It's good to know, even so, all dust is to be avoided.


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## dc_ni (21 Feb 2015)

Here is what the HSE has to say about MDF:

http://www.hse.gov.uk/woodworking/faq-mdf.htm


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## Graham Orm (21 Feb 2015)

Quote from the HSE document in the link added by dc_ni above :-

"What are the dangers of working with MDF compared with softwoods, hardwoods or other panel products?
The atmosphere created by machining or sanding MDF board contains a mixture of softwood dust and hardwood dust (if it is present). In addition, there will also be free formaldehyde, dust particles onto which formaldehyde is adsorbed and potentially, the resin binder itself and its derivatives. However, the levels of free formaldehyde in boards made within the EU at levels of formaldehyde class E1 are thought to be insignificant. This is because at these levels the resin is fully reacted (polymerised) – see Q.4 & Q.5 for information on standards and classes.

Under current legislation softwood dust, hardwood dust and formaldehyde are considered to be hazardous to health. Both softwood and hardwood dusts are known to be respiratory sensitisers and may cause asthma and other respiratory problems. Hardwood dust can also cause a rare form of nasal cancer.

Formaldehyde is classified in the UK, and in the European Union as a carcinogen and it carries the hazard statement ‘suspected of causing cancer’."


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## DennisCA (21 Feb 2015)

I've used MDF and I found the dust atrocious and the jigs I made with it sagged or got bent, including two table saw sleds, both got warped as bananas. Fortunately I have access to cheap birch plywood via my work, 3x12mm and 3x18mm full sheets for 100 euros isn't bad. Only B/BB grade with patches, and IIRC I might have found a cavity once or twice, but it has as many laminations as proper baltic birch plywood.


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## lurker (21 Feb 2015)

I was trying to get this in context. The cancer thing is very unlikely.
COPD ( look it up) from respirable dust is of a far greater magnitude , I'd guess a thousand fold
So..........if you take the same precautions with mdf as you ought to be doing with other woods the risk is not significantly different
Believe me cancer should be very low on our , as woodworkers, list of concerns.
There are people on this forum who have become so sensitised to certain wood they have had to pack it in.

And before anyone mentions the high Wycome throat cancer clusters yes I am aware, as they formed part of my thesis


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## Stu_2 (21 Feb 2015)

I''ve got a few jigs made from 12mm and 18mm MDF, all made from off-cuts. They work a treat.


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## mseries (21 Feb 2015)

Years ago when I was starting out I made a tenon jig which was basically a box with a 6mm MDF top screwed to two sides which where inturn screwed to a contiboard base. I worked indoors at the time. Years later after I was forced to relocate to the garage I reused the jig and found my tenons were not parallel. The MDF had swelled and bowed. Same thing may have happened with other organic material I suppose . I keep saying I am going to seal 'wooden' jigs somehow but rarely do, I just make another if it goes pear shaped !


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## finish_that (21 Feb 2015)

Commercial grade ie. thick laminate flooring is worth looking for jig material - very tough and slippery faces
plus you can laminate.. it to make thicker stock.


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## Steve Maskery (21 Feb 2015)

It's horses for courses. Do you want it to be slick and slippery (UHMW)? Do you want it to be cheap (MDF)? 
MDF is my first call, and if an idea works I might remake it in MRMDF. A really successful idea might be remade again in phenolic.

I'd like to make my tenon jig in phenolic. But it all depends on how much time/money/effort you want to invest in an idea.

S


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## condeesteso (22 Feb 2015)

Steve Maskery":3ql9os53 said:


> It's horses for courses. Do you want it to be slick and slippery (UHMW)? Do you want it to be cheap (MDF)?
> MDF is my first call, and if an idea works I might remake it in MRMDF. A really successful idea might be remade again in phenolic.
> 
> I'd like to make my tenon jig in phenolic. But it all depends on how much time/money/effort you want to invest in an idea.
> ...



Totally agree, mdf is excellent for most uses - of course we all know it isn't stiff but it's easily braced. It's cheap, fast to work precisely, clean edges etc. Benefits from a quick seal - acrylic is very good for locking the fibres down (edges) and dries in minutes. Obviously ply is stiffer, so it depends on application surely.
And mdf emits a funny smell when machined - something that definitely isn't soft or hardwood, more chemical.


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## custard (24 Feb 2015)

lurker":1aq802wh said:


> What makes you think mdf is a carcinogen?



http://www.hse.gov.uk/woodworking/faq-mdf.htm

Carcinogenic or not, I'd rather not get any in my lungs!


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## custard (24 Feb 2015)

Different jigs may perform better in different materials. 

MDF is stable and has a uniform thickness. It's easily crushed, doesn't take fastenings well (although there are workarounds to this), and sags under its own weight.

Plywood is more stable than solid wood, but it's rarely all that flat and thickness can vary even within a single sheet. It takes fastenings fairly well and is quite a bit more rigid and robust than MDF.

I'll use both materials for jigs, for example the base of my long veneer shooting board is MDF because above all else I want flatness, I just know to treat it carefully to guard against crushing the corners (if it was a jig in a shared workshop I'd put a hardwood lipping on). The base board for the jigs I use to form curves on a spindle moulder are ply, because I'll be screwing holdfast clamps into it and they need to be well secured, the actual master profile that I'll be copying from is MDF because that's more easily shaped to a smooth fair curve.

Think about what you want the jig to do then choose materials accordingly.


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## Job and Knock (27 Feb 2015)

For routing acrylic is better (especially as you can get offcuts for peanuts from signwriters), Tufnol (re-inforced phenolic plastic) better yet and HPL (high pressure laminate - think toilet cubicle walls, changing rooms, etc - another form of phenolic) is best of all IMHO. The dusts off all of these is pretty nasty, though, not good for the lungs

As for MDF - with "E1" the formaldehyde level is less than it is on pine - although the Daily Mail would have folk believe it's the next killer asbestos. The issue with it is the fine dust - and fine dusts can cause all sorts of respiratory problems.


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## stuartpaul (28 Feb 2015)

There is always a need to be careful with such sweeping statements as 'it's carcinogenic'. This can lead to massive and uncalled for over-reaction (e.g. mdf banned in schools).

It's also worth remembering that virtually all HSE limits are based on a time weighted average (TWA) of an 8 hour working day. Thus, most diyers are unlikely to come anywhere near any of the limits. Full timers need to be much more careful and consider the occupational exposure standards.

That said all dusts are an issue and care needs to be exercised.


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## Claymore (9 Mar 2015)

.........


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## iNewbie (3 Apr 2015)

Anybody tried this Panzerholz link


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## Graham Orm (3 Apr 2015)

Expensive I imagine


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