Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Wood Care: => Topic started by: Mike0001 on October 20, 2014, 08:05:48 pm

Title: cutting thin plywood
Post by: Mike0001 on October 20, 2014, 08:05:48 pm
1.5 mm ply

so what do I have, well jigsaw with metal cutting blades, also have a dremel ( just a dremel )

What would be best way to cut ply ( Cutting out the main components of plan ) I would guess I would get lots of vibration with a jigsaw but that's what I have

thanks
Title: Re: cutting thin plywood
Post by: Colin Bishop on October 20, 2014, 08:08:15 pm
I think most people would simply use a sharp knife.

Colin
Title: Re: cutting thin plywood
Post by: essex2visuvesi on October 20, 2014, 09:15:03 pm

A jigsaw is a little overkill for thin ply

Always best to have the right tool for the job*:-
http://www.ebay.co.uk/itm/LARGE-HEAVY-DUTY-SAW-OR-6Pc-SET-Wood-Jewellery-Model-Making-Sawing-Cutting-Kit-/310839320950?pt=UK_BOI_Building_Materials_Supplies_Carpentry_Woodwork_ET&var=&hash=item485f77a176


*Other fret saws are available*


You could get a powered one but I and many others find you get better control with a hand saw.
Title: Re: cutting thin plywood
Post by: Capt Podge on October 20, 2014, 09:37:59 pm
I think most people would simply use a sharp knife.

Colin

Stanley Knife. That's all I ever use on thin ply - just ensure the blade is sharp (if  isn't, then change it), keep your hands behind the blade (been there, done that) and use a guide for the blade, preferably metal.
Also, use several light strokes - Don't force the blade - you'll get through the wood eventually. O0
...Oh, beware of what's lying underneath your work piece as well :embarrassed:
 
Regards,
 
Ray.
 
Title: Re: cutting thin plywood
Post by: RAAArtyGunner on October 20, 2014, 09:46:47 pm
A jigsaw is a little overkill for thin ply

Always best to have the right tool for the job*:-
http://www.ebay.co.uk/itm/LARGE-HEAVY-DUTY-SAW-OR-6Pc-SET-Wood-Jewellery-Model-Making-Sawing-Cutting-Kit-/310839320950?pt=UK_BOI_Building_Materials_Supplies_Carpentry_Woodwork_ET&var=&hash=item485f77a176


*Other fret saws are available*


You could get a powered one but I and many others find you get better control with a hand saw.

As Essex says, The deeper the throat the better, which is dictated by how big the sections are that you are cutting out.

For smaller sections though, you could use a coping saw.
Title: Re: cutting thin plywood
Post by: Mike0001 on October 20, 2014, 09:52:03 pm
never even thought of cutting with a knife, not sure if I would trust myself though , one slip and blood everywhere

might try the fret saw , that sounds good as well, can go at my own pace which I like

will report back tomorrow with hopefully some shapes cut out


thanks all a great help  :-))
Title: Re: cutting thin plywood
Post by: Colin Bishop on October 20, 2014, 10:24:14 pm
Always cut away from yourself to preserve your person! A light cut first to guide the blade before exerting pressure.

Colin
Title: Re: cutting thin plywood
Post by: Neil on October 20, 2014, 10:43:07 pm
will report back tomorrow


that's as long as ya still have fingers to type with, lol {-) {-) {-)

and what's a little blood shed in the name of ya hobby............so long as ya haven' got ebola. %% %%
Title: Re: cutting thin plywood
Post by: dreadnought72 on October 21, 2014, 12:46:04 am
I cut thin ply using a Stanley knife against the flat edge of a plaster float - keeps your non-knife fingers well out the way.
Title: Re: cutting thin plywood
Post by: rickles23 on October 21, 2014, 09:29:36 am
Hi,

Safest way is to use a steel rule.

Regards
Title: Re: cutting thin plywood
Post by: tigertiger on October 21, 2014, 10:17:40 am
One thing I found out about knives.
A good full size Stanley knife (or similar heavy knife) cuts much better than lighter knives, even those with the same blade.
The knives with the snap off blades are never as good.
Title: Re: cutting thin plywood
Post by: dougal99 on October 21, 2014, 10:48:47 am


and what's a little blood shed in the name of ya hobby............so long as ya haven' got ebola. %% %%


Any blood on the work piece can ruin the finish. Make sure it drips on the bench or floor  8)
Title: Re: cutting thin plywood
Post by: grendel on October 21, 2014, 01:11:55 pm
You really don't want a standard steel rule for cutting, generally if you slip the blade will skid across the rule to where you are applying the pressure, you need a proper cutting rule, with grooves to trap the blade if it slips, similar to the attached image.
where I worked once Stanley knives were banned totally, I was the one exception as there was no other safer knife to cut the foam mounting boards I used in the drawing office, (the only thing we found able to cut them was over £4000) so when cutting I had to use the relevant cutting rule and wear a pair of Kevlar cut resistant gloves.
Grendel
Title: Re: cutting thin plywood
Post by: essex2visuvesi on October 21, 2014, 09:59:27 pm
The knives with the snap off blades are never as good.
And dangerous if used for cutting inappropriate materials
Title: Re: cutting thin plywood
Post by: Colin Bishop on October 21, 2014, 10:08:30 pm
No modeller is worthy of the name unless they have a good selection of lethal instruments in their toolbox including modelling knives, scalpels, razor saws and other sharp and pointed implements.

Plus glues and other liquid substances which give off toxic fumes.

It's what the hobby is all about.

Colin
Title: Re: cutting thin plywood
Post by: radiojoe on October 21, 2014, 11:30:06 pm
I agree with Colin, I'm a retired carpenter in a carpenters tool box you'll find more sharp edged tools than anywhere else, I worked with them for over 50 years and still have all my fingers,  you just have to respect them and use them responsibly, I always cut thin ply with a Stanley knife, it leaves a nice clean edge.
Title: Re: cutting thin plywood
Post by: derekwarner on October 22, 2014, 01:51:46 am
 :-)) once cut 5/8"wide planking from a 5' x 3' x 1/16" thick sheet of marine ply

I found buy using a 6' straight edge clamped down on each end of the ply sheet greatly enhanced the cutting procedure without my left hand needing to secure  the straight edge & keep it in line

The cutting surface was a redundant internal door  O0 ....the cutting instrument was a standard Stanley single blade knife  :-)) Derek
Title: Re: cutting thin plywood
Post by: Flundle (Speedline Models) on October 22, 2014, 03:10:09 pm
Use a laser-cutter!
If you have them as an electronic file send them to me and Ill cut out the parts for you.
If not then send them anyway and I see what can be done.


Title: Re: cutting thin plywood
Post by: Flundle (Speedline Models) on October 22, 2014, 03:12:22 pm
That should have gone on to say that I will cut them for you. If not then send them anyway and Ill see what I can do.

Title: Re: cutting thin plywood
Post by: Neil on October 22, 2014, 07:37:41 pm

Any blood on the work piece can ruin the finish. Make sure it drips on the bench or floor  8)

unless yer building a fire boat......then it's well camouflaged :} :} :} :} :} :} :}
Title: Re: cutting thin plywood
Post by: missyd on February 24, 2017, 06:43:21 pm
I use my Proxxon bandsaw to cut any wood (incl. plywood) thicker than 1mm.
Title: Re: cutting thin plywood
Post by: LJ Crew on February 24, 2017, 08:58:42 pm
During my spell as CDT Technician we insisted that students cutting paper, thin wood etc. with a knife, use a "safety Ruler" normal length and width but with a groove down the middle. It either protected the ends of fingers, or channeled the blood away!
Title: Re: cutting thin plywood
Post by: RAAArtyGunner on February 24, 2017, 11:05:26 pm
During my spell as CDT Technician we insisted that students cutting paper, thin wood etc. with a knife, use a "safety Ruler" normal length and width but with a groove down the middle. It either protected the ends of fingers, or channeled the blood away!

It was for the later so you could see to keep cutting till finished.
Title: Re: cutting thin plywood
Post by: sparkey on February 25, 2017, 09:57:51 am
 :-)) Steel rule and a Stanley knife,just keep scoring till through or snaps clean :-)) 
Title: Re: cutting thin plywood
Post by: tonyH on February 25, 2017, 01:51:12 pm
If you use an old steel rule and stick medium grade sandpaper on one face with d/s tape, it doesn't slip on the work.
Even better, using a single carpet edge I.e. the one with a 'J' profile (WITHOUT spikes!), again with the sandpaper, you get a 3ft rule with built-in finger guard.


Works for me :-))
Title: Re: cutting thin plywood
Post by: rickles23 on February 25, 2017, 03:02:59 pm
Hi,


If not for the modeling brigade, Band-aids would go broke.


regards
Title: Re: cutting thin plywood
Post by: RAAArtyGunner on February 25, 2017, 10:47:27 pm

Yes, any type of metal profile with finger protection is way to go. :-)) :-))

Not only for plywood but same "tools" for cutting styrene etc.

Fingers are important and much better using above tools than going to emergency spewing blood everywhere. <*< <*<
You need to keep all the blood you have. O0 O0
Title: Re: cutting thin plywood
Post by: Tug-Kenny RIP on February 26, 2017, 11:14:48 am

I would like to see people's pictures of the finger guard cutting rulers please.  How many types and recommendations can the members show and which is the best in your opinion.

I am still looking for the ultimate best tool for the job, as I'm running out of bandages.

Cheers

ken
Title: Re: cutting thin plywood
Post by: Nemo on February 26, 2017, 09:35:09 pm
As others have said, a Stanley knife with a good blade is adequate for thin ply - it has never failed me. As for safety, I use a length of 3/4" light aluminium angle - safe as houses Kenny! :-)) (I have one of those rulers and found them not very good at protection of my digits)
Title: Re: cutting thin plywood
Post by: Tug-Kenny RIP on February 26, 2017, 09:45:49 pm
Thanks Nemo.   I find that aluminium tends to be shaved  (over time) by the blade, so a steel version with a protection shield is the thing to look out for.

ken
Title: Re: cutting thin plywood
Post by: grendel on February 26, 2017, 10:09:48 pm
I have a metre rule, with 2 big grooved for the blade and multiple smaller ones between
Title: Re: cutting thin plywood
Post by: Stavros on February 26, 2017, 10:11:39 pm
Ok has anyone used a Chain mail glove....like the ones the butchers use




Dave
Title: Re: cutting thin plywood
Post by: RAAArtyGunner on February 27, 2017, 12:42:17 am
Thanks Nemo.   I find that aluminium tends to be shaved  (over time) by the blade, so a steel version with a protection shield is the thing to look out for.

ken

Ken,
A Solution.
Lower the blade angle so it "rests" against the guide.
A near vertical angle will tend to "cut into" whatever guide you are using. Instead of drawing the blade across the surface.
The lower angle puts more blade against the guide, straighter cut less effort reduced slippage.

Unless you change the angle, you will still shave the steel guide and blunt your blades more frequently. O0 O0

I use a cutter with a wide adjustable blade, the snap off type, this allows more or less blade to be exposed for the task at hand.
Also I always re-hone the blade after use, until it is past its use by date, before breaking off the "end".
Stanley knives don't give you very good control during use, as they are more suited for harder, less accurate rougher work.
My other knife is a scalpel, but  watch the fingers because it is painless cutting them.

Look closely at a 'Stanley' blade and you see it's cutting edge is 'V' shaped which does not allow accurate cutting along a line or straight edge. The same applies for the adjustable blade knife, however the blade is thinner and you can expose more blade length so that the flat of the blade runs along the straight edge.

My knives are like chisels, different ones for different tasks but the main two used are,
1. Wide break off blade type
2. Scalpel, with several with different blade shapes.

Practice it and see how you go.
Title: Re: cutting thin plywood
Post by: rickles23 on February 27, 2017, 03:33:53 am
Hi,


When cutting always use soft strokes.


I use at least three strokes of the blade to make one cut.


Regards

Title: Re: cutting thin plywood
Post by: Nemo on February 27, 2017, 07:00:00 pm
As Mr Punch would say - 'That's the way to do it!'  :-))
Title: Re: cutting thin plywood
Post by: grendel on February 27, 2017, 08:17:21 pm
Ok has anyone used a Chain mail glove....like the ones the butchers use




Dave
yes, but not for model making. that said I was given a pair of kevlar gloves at work, for use when they banned stanley knives, after finding the alternative to cut the foamboard for the signs I used to make at £30,000 they gave in and let me use the stanley knife - with the gloves (the alternative to cut 3mm foamboard was a powered guillotine).
Title: Re: cutting thin plywood
Post by: Tug-Kenny RIP on February 27, 2017, 08:23:05 pm
 
I knew there must be more to it than I thought.  Thanks for the ideas fellas.    :-))

ken