Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: rmaddock on July 29, 2011, 06:19:35 pm

Title: Manly advice required please.
Post by: rmaddock on July 29, 2011, 06:19:35 pm
Hello chaps!

I'm hoping that some of you mature, men of the world types can give me some manly advice.  :embarrassed:

How do I get my electric jigsaw to cut straight?  {-)

When I cut stuff....and I always get what seems the right blade....no matter how thick, I seem to end up with the blade twisting to almost 45 degrees. I cut along my lines but the edges are unintentionally chamfered  <:( I even tried buying a new saw and it didn't help.  >>:-(

Am I doing something obviously wrong? Is there a technique I don't know about? Am I simply incompetent?

Cheers!

Robert.
Title: Re: Manly advice required please.
Post by: DickyD on July 29, 2011, 06:39:28 pm
Do not force the saw to turn. Let the saw do the work at its own speed. :-))
Title: Re: Manly advice required please.
Post by: rmaddock on July 29, 2011, 06:54:44 pm
I've tried using the force  %)
I'm sure it must be something like that but the last thing I cut was very thin fibre board. The saw was ripping through it and still cutting sideways.
Is it really just me?
Title: Re: Manly advice required please.
Post by: Colin Bishop on July 29, 2011, 07:03:56 pm
If the blade is properly mounted and the supporting platen is flat on the job then the cut should be vertical. Something, somewhere, is moving!

Colin
Title: Re: Manly advice required please.
Post by: Corposant on July 29, 2011, 07:11:20 pm
Robert

The only things I can think of are:

If the angle of the baseplate is adjustable, does it form a 90deg angle with the blade?

Is there any lateral play in the actuating mechanism? (Unlikely in the case of a new saw!)

Are you pushing it too hard horizontally? If the blade is set vertical to the work and the teeth have removed all they can before being moved forward, then the cut ought to stay vertical - that's the theory anyway!

In my experience thick chipboard (e.g. kitchen worktop) is particularly vulnerable to the problem you describe. It needs very firm pressure to keep the baseplate flat against the surface and if the cut starts to wander from the vertical, it's virtually impossible to correct. With thick materials also it's more difficult to refrain from pushing hard horizontally (the job seems as if it's never going to end!).

I'm sure you'll get lots more advice soon!

Mike
Title: Re: Manly advice required please.
Post by: Corposant on July 29, 2011, 07:19:43 pm
Robert

From your reply to Richard, it appears you might benefit from using a fence - i.e. clamp a straight strip of wood to the work before you start.

Mike
Title: Re: Manly advice required please.
Post by: Tug-Kenny RIP on July 29, 2011, 07:51:06 pm

I assume the cut is not vertical at 90 degrees to the surface, from what you say, rather than it wandering from the line.

I snap the blade off  (with heavy pliers) at a depth suitable to the timber I'm cutting as a long blade does  'flap about'  at speed.  The number of teeth per inch also has a bearing on the ease of cut.

Hope this helps

Ken

Title: Re: Manly advice required please.
Post by: rmaddock on July 29, 2011, 07:56:57 pm
I assume the cut is not vertical at 90 degrees to the surface, from what you say, rather than it wandering from the line.

Yes Ken, that's the problem.

Perhaps I should try using a fence, as Mike suggests.

I'm asking 'cause any day now I want to cut out a stand for the Nobby and I'm worried that I'll make a mess. Of course, if I could get the chamfer right, it'd fit the hull perfectly.  {-)
Title: Re: Manly advice required please.
Post by: john s 2 on July 29, 2011, 07:59:59 pm
No doubt you know that there are a lot of different blades avaliable. This may help John.
Title: Re: Manly advice required please.
Post by: rmaddock on July 29, 2011, 08:09:27 pm
No doubt you know that there are a lot of different blades avaliable. This may help John.
Yes, thanks John. I seem to spend a fortune on just the right blade every time.
Title: Re: Manly advice required please.
Post by: Shipmate60 on July 29, 2011, 11:22:31 pm
Is it a cheap make or expensive make.
I have 1 which does the same whatever I do to it, (Yes I do know how to set it up), but borrowed a more expensive one today for cutting out worktops and it was fine!!!

Bob
Title: Re: Manly advice required please.
Post by: essex2visuvesi on July 29, 2011, 11:33:41 pm
Is it a cheap make or expensive make.
I have 1 which does the same whatever I do to it, (Yes I do know how to set it up), but borrowed a more expensive one today for cutting out worktops and it was fine!!!

Bob

Yep I had one of those as well... has never made a successful 90deg cut since i had it.  The problem with mine was the saw base.  It had was adjustable but being cheap it wasnt able to set itself at 90deg so I did the same as you and bought a dewalt as they were on special offer. and never had a problem since.

Another tip always check your blade is straight by laying it on a flat surface
Title: Re: Manly advice required please.
Post by: Peter Fitness on July 30, 2011, 12:11:59 am
Try the fence idea first. If you are unintentionally applying lateral force to the saw, the fence should stop it.

Peter.
Title: Re: Manly advice required please.
Post by: rmaddock on July 30, 2011, 05:38:06 pm
Thanks all.
Yes, It was a cheap one...but not as cheap as the first one. As far as I can tell, the sole plate is at 90 degrees. I'll try a fence as it probably is me pushing sideways.
However, that's not going to help much when I want to saw curve to fit the boat hull.
Perhaps I'll go old school and use the fret saw. I can do that.
R.
Title: Re: Manly advice required please.
Post by: john s 2 on July 30, 2011, 08:43:45 pm
I use a small set square to ensure blade is 90 degree to baseplate. John.
Title: Re: Manly advice required please.
Post by: rmaddock on July 30, 2011, 08:47:43 pm
I use a small set square to ensure blade is 90 degree to baseplate. John.
It wouldn't have occurred to me that that level of accuracy was required. I shall give it a go.
Title: Re: Manly advice required please.
Post by: John W E on July 30, 2011, 08:58:29 pm
Hi rmaddock
Can you tell us what make the jig saw it is ? also how are the blades located into the jig saw

aye
john
Title: Re: Manly advice required please.
Post by: rmaddock on July 30, 2011, 09:09:40 pm
Hi rmaddock
Can you tell us what make the jig saw it is ? also how are the blades located into the jig saw

aye
john

Off the top of my head I can't remember what make it is, and it's far to late and dark to venture into the dark and scary cellar. However, I suspect it was B&Q's premium budget line.....if that makes sense. :embarrassed:

The blades have a bayonet fitting and there's a roller sits against the back edge of the blade. It also has speed and pendulum settings which are beyond me......especially as I've filed the instruction manual somewhere. >>:-(
Title: Re: Manly advice required please.
Post by: Colin Bishop on July 30, 2011, 09:15:50 pm
It always helps to read the instructions....
Title: Re: Manly advice required please.
Post by: nemesis on July 30, 2011, 09:17:11 pm
Hello, It is an obvious thing but keep you waste side to the right. nemesis
Title: Re: Manly advice required please.
Post by: nhp651 on July 30, 2011, 10:20:30 pm
you might also find that keeping your "leed eye" the one you site with directly over the blade and cutting line will help.
if you watch the cutting process and the line you are following from a side aspect, you will tend to push away from that line and then re compensate for your deviation by pulling back on the saw, the blade will flex and you'll end up with that obtuse angle of cut that you are finding you have.
i have both cheep and very expensive jig saws, and like any cut you make, be it with a craft knife, chisel or a saw, power or hand, unless your siting eye is directly over the cutting blade, you'll ALWAYS  end up with an angled cut.

don't change your saw, just change your cutting technique. :-))

neil.
Title: Re: Manly advice required please.
Post by: Korky on July 30, 2011, 10:24:43 pm
Sounds to me like you need to get the missis to have a stern word with this wayward saw....simples   innit ?
Title: Re: Manly advice required please.
Post by: dodgy geezer on July 30, 2011, 10:36:15 pm
No doubt you know that there are a lot of different blades avaliable. This may help John.

I second that.

I have a few expensive blades, and a lot of cheap ones. The cheap ones are quite thin, and flex a lot. When I cut through wood much thicker than about 3/8", they wander off-line.

The expensive ones are thicker, and much stiffer. When I cut through 1" wood, they stay in line....
Title: Re: Manly advice required please.
Post by: DickyD on July 30, 2011, 10:43:45 pm
Off the top of my head I can't remember what make it is, and it's far to late and dark to venture into the dark and scary cellar. However, I suspect it was B&Q's premium budget line.....if that makes sense. :embarrassed:

The blades have a bayonet fitting and there's a roller sits against the back edge of the blade. It also has speed and pendulum settings which are beyond me......especially as I've filed the instruction manual somewhere. >>:-(
Try cutting at a slow speed.
Title: Re: Manly advice required please.
Post by: RaaArtyGunner on July 30, 2011, 11:19:06 pm
Mate,           

Using a fence will not help as the blade is "bending" under load and not cutting "vertical" that is, it is not straight up and down.

It is important to take time when setting the blade vertical to the base and making sure it contacts with the rear blade support, usually a roller bearing/wheel, when under load.

As Dickey has Said go slow take your time and adjust the speed to suit. The faster the motor speed and cutting the hotter the blade gets causing it to bend from the vertical.
Title: Re: Manly advice required please.
Post by: derekwarner on July 31, 2011, 03:30:30 am
 :D...just another thought of misconception  {-) ..a jigsaw cut finish is not really intended to be a final/finished   surface of a finished    product  :P

Scroll saw cuts  are also subject to wander >:-o >>:-( <*< .....

As others have suggested...patience, lower speed, lower force/pressure, blade selection, blade alignment & a fence....... :-)) ....all good points Derek
Title: Re: Manly advice required please.
Post by: Tug-Kenny RIP on July 31, 2011, 04:28:40 pm
Off the top of my head I can't remember what make it is, and it's far to late and dark to venture into the dark and scary cellar. However, I suspect it was B&Q's premium budget line.....if that makes sense. :embarrassed:

The blades have a bayonet fitting and there's a roller sits against the back edge of the blade. It also has speed and pendulum settings which are beyond me......especially as I've filed the instruction manual somewhere. >>:-(

Saw this and my heart stopped.    :o

Are we fighting a computer control wizard. What does this mean --- 'pendulum'.  Do you reckon the machine is doing it's thing ?

ken

Title: Re: Manly advice required please.
Post by: rmaddock on August 02, 2011, 02:39:51 pm
Okay, thanks everybody.
I bought some new blades this morning.....no choice except "proper" brands in our local B&Q. I did discover that the one I had were very short...designed for fretwork etc. That wont have helped.

Anyway, I took my new blades and all your advice and did some zen sawing of old Ikea units today. Lovely results. I've now got a boat stand for the Nobby to be (reasonably) proud of. You can see the results HERE (http://www.modelboatmayhem.co.uk/forum/index.php?topic=30888.msg314105#msg314105).
Title: Re: Manly advice required please.
Post by: RaaArtyGunner on August 03, 2011, 03:43:58 am
Okay, thanks everybody.
I bought some new blades this morning.....no choice except "proper" brands in our local B&Q. I did discover that the one I had were very short...designed for fretwork etc. That wont have helped.

Anyway, I took my new blades and all your advice and did some zen sawing of old Ikea units today. Lovely results. I've now got a boat stand for the Nobby to be (reasonably) proud of. You can see the results HERE (http://www.modelboatmayhem.co.uk/forum/index.php?topic=30888.msg314105#msg314105).

Well done :-)) :-))
Title: Re: Manly advice required please.
Post by: Nordsee on September 07, 2011, 08:34:30 pm
Off the top of my head I can't remember what make it is, and it's far to late and dark to venture into the dark and scary cellar. However, I suspect it was B&Q's premium budget line.....if that makes sense. :embarrassed:

The blades have a bayonet fitting and there's a roller sits against the back edge of the blade. It also has speed and pendulum settings which are beyond me......especially as I've filed the instruction manual somewhere. >>:-(
Speed controls are used for various thicknesses of wood, Pendulum is for when you cut straight , no pendulum when cutting curves. Fine teeth blade, high speed, coarse teeth , slow speed. Buy good blades, that is the begin and end all. Cheap blades are mostly a waste of cash.Do not push too hard, let the saw do the work. If you are cutting laminates you need a special blade for them.
Title: Re: Manly advice required please.
Post by: irishcarguy on September 08, 2011, 07:00:12 am
NEVER buy cheap tools they always break or go wrong at key moments, people ask me why I use expensive Snapon tools, the short answer is I lose fewer knuckles.Mick B.
Title: Re: Manly advice required please.
Post by: essex2visuvesi on September 08, 2011, 10:06:58 am
Agreed on the tools front

tho some of my tools are cheapies the ones in regular use are all either snap on or draper
Title: Re: Manly advice required please.
Post by: catengineman on September 08, 2011, 10:14:55 am
I loaned out some tools once.
The chap saying they were "cr8p" so he left them in his garden shed and why did I not loan him my snap-on stuff?
.
now let me see?
nope can't think of a reason why I would loan out MY tools
Title: Re: Manly advice required please.
Post by: treeboa on September 08, 2011, 10:41:36 am
anyone wanting to borrow my snap on gear is told to go forth and procreate  O0, i came to this decision many years ago when i lent someone my black impacts, got them back 2 weeks later  covered in surface rust, his attitude was its only a bit of rust --wire wool will sort it, got a bit shirty a few weeks later when i refused to lend him  my mig
Title: Re: Manly advice required please.
Post by: essex2visuvesi on September 08, 2011, 10:42:03 am
I used to with a 500 quid deposit  :D