Sign up Latest Topics
 
 
 


Reply
  Author   Comment  
Frankg

Avatar / Picture

Registered:
Posts: 208
Reply with quote  #1 
This is an age old problem with me and I do not know how to figure it out. [confused]What is causing my scroll saw to cut like this. I always seem to have this problem when I'm cutting 3/4" stock. In this case it is MDF. If anyone has had this problem and solved it,[idea] I would love to have a solution.[biggrin] I've checked my tension; seems normal tight. If I try to make it any tighter my blade slips out. The blade is a standard #7 flying Dutchman and a fairly new one. I expected a straight 90 deg. angle cut. Thanks for your help on this.  Scroll cut2.jpg   

__________________
Frank Galica
https://www.etsy.com/shop/Franksworld
Ken Martin

Avatar / Picture

Registered:
Posts: 988
Reply with quote  #2 
Frankg

I have had this problem a lot.

Sorry to ask, but the table is 90 degrees to the blade correct?

First check the tension, which it sounds like you did, then change blades (they don't last very long) then be sure you are not pushing the blade to fast through the work, or putting pressure on the blade from the right or left with your hands. Try different cutting speeds if you scroll saw is adjustable.   Also try a different blade company all together.  I like to use Olsen's PGT Skip/Reverse Tooth blades most of the time.  Cutting MDF you should not be having this problem with a number 7 blade.  I use a number 5 blade most of the time on any thing up to 3/4" up to 1" thick before I even start thinking about a bigger blade.

Also, check the height of the bottom of the arm of the saw from the front to the back.  They do get off sometimes and if it is off it can make a difference in how the tension affects the blade.

Seems every time I have the problem I see above it is caused by the little allen set screw to the left side of the slot that holds the blade in.  You know when you put a new blade in, you tighten the blade in with the knob on the right (they say not to over tighten the blade because it will bend it.
If the little allen set screw on the left is to far out the blade will bend into the hole created when you tighten it.  If the little allen set screw on the left is to far in the blade won't sit straight.  This applies to both the top and bottom blade holder.

Before I start a project I always put in a new blade and do three tests.
1.  Check to see the tension is right and the blade is 90 degrees to the table with a square
2.  Start a cut (very shallow) then stop and turn the piece around to the back of the blade and if it is true 90 degrees it will slip right into the cut you just made.  If it does not something is wrong.  Usually the table and blade are not lined up.
3.  I like to make a U-shaped cut in a scrap section of the material and look to see if all the edges are straight.  If one edge of your sample cut is flat lay it on the table and you will see real quickly if you have any deflection of the blade around the cut.  If so check and adjust everything and check everything again, because it won't get better by itself.

I hope some of the above helps.  I am just a beginner myself so I don't have many of the answers.

I know there are some great scrollers out there, so lets hear how you solve this problem when it happens to you.

__________________
Kenneth W Martin
http://FuzzyDuckCreations.com/
https://www.etsy.com/shop/FuzzyDuckCreations
Udie

Avatar / Picture

Registered:
Posts: 1,179
Reply with quote  #3 
Ken - That's great advice, excellent post.
I too hope that some members can offer their observations and solutions.
phantom scroller

Avatar / Picture

Registered:
Posts: 876
Reply with quote  #4 
Frank it good advice from Ken the only issues I've had is tension,blade size, blunt blade, angle and yourself pushing into the blade and not letting the blade do it's job. Double check the angle make yourself a 90 deg small piece of hardwood to press up to the blade a fraction out and you will see the difference on 3/4" wood.
__________________
Roly

https://www.facebook.com/Scrollsaw-Woodworker-578378898839152/
ctowne

Avatar / Picture

Registered:
Posts: 1,054
Reply with quote  #5 

I have had this same problem.  And it is very obvious when cutting a 1.5" piece for a car.  I had done the things that Ken mentioned above but it ended up being the operator (like so many things).  I have slowed down on tight curves.  I was trying to force it too much and like Roly mentioned above, let the blade do the work.  There was an article I read and I cannot find it to post here, about how the top of the piece cuts first and you have to let the blade complete the cut vertically as you are making the turns.  I'm not sure of that but after reading, I adjusted my speed in turns and I can get a 90 degree cut with a fresh blade.
Cindy

Frankg

Avatar / Picture

Registered:
Posts: 208
Reply with quote  #6 
Hey all,

Thanks for your inputs. Lots of good input. As Ken suggested my table top was off a few degrees.[rolleyes] I don't know how that happened but that's what I found. The other thing is I am always rushing to get pieces cut because of high volume needed for craft shows.[crazy] I also struggle with blades being used to long cuz I'm a cheapskate and want them to last as long as possible. [sneaky]
I have  an old 2 speed Dremel Scroll saw and I have to change the blades in the holders that use set screws (no convenient knob). So part of my motive to last longer is it takes time to change the blade. [frown]
I'm not sure at what feed rate I should run at. Is there a chart or table that gives an idea of how fast to cut? For example a # 7 blade cutting 3/4" material (For each type of wood listed) you should be cutting (for example)at a rate of 1 inch per 6 seconds and of course the saw speed would be a factor too. Maybe Udie has some ideas on this?

__________________
Frank Galica
https://www.etsy.com/shop/Franksworld
Udie

Avatar / Picture

Registered:
Posts: 1,179
Reply with quote  #7 
Frankg
Some of what you are looking for is right here on Toymakingplans.com web site.
Go to  the tab on the home page for Wood Toy Workshop.
Then you will see ...
 Blade Selection.jpg
Click on the photo above and it will take you to an article. There is a chart there that recommends scroll saw blade numbers to wood thicknesses.

A chart for feed rate for various wood types - sorry buddy, I have not run across one.
That does not mean it does not exist, just that I have not run across one.
Maybe one of our members can point you in the right direction.

Dremel Scroll Saw - One of my scroll saws is a Dremel Model 1671.
I contacted Dremel and requested them to e-mail me the parts schematic and list for this model.
I then ordered some replacement parts.
One group of parts were the replace components for my pinned blade holder assembly, top and bottom.
At the same time I ordered all the components necessary to convert my scroll saw to a pin less model.
Lucky for me this conversion option was available.
So, my friend, give Dremel a call and see if they can help you also.

Most of my scroll saw work is done using pinned blades, and replacing blades is not a problem.

I just posted a new topic called "Scroll Saw Tune Up - Blade to Table Surface" to this section. I think it will be of interest to you also.

Hope this helps.

Marlowes woodcraft

Avatar / Picture

Registered:
Posts: 10
Reply with quote  #8 
I too have had this problem when scroll sawing. I believe the problem comes from applying some side pressure when rounding a corner.  The feeding pressure should come from directly in front of the blade not from either side. Also the blade must be tight and in good condition (not dull).
Old Texan

Registered:
Posts: 3
Reply with quote  #9 
You have had some good answers to your question, but one thing I have not seen mentioned.  check for 90 degrees front and back as well as left and right.  if off front to back it will show up only on tturns.
it is difficult to correct but can be fixed most often.  sometimes it is worse on specific saws., due to way they are manufactured. sometimes you have to raise or lower the front or back of your table.
good luck
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.