I use whatever is required to best make the project. Yes, that means sometimes using blades of various sizes, brands, and even both flat and spiral all on one project. I have been at this for over 20 years. It is something you learn over time and not everyone does the same thing and that is all well and good.
Just amazing. Truly an art treasure for your family. For the record your grandfather might have actually used a scroll saw. They have been around a lot longer than most of realize. Check out this article.
http://scrollsawer.com/2010/10/14/the-early-history-of-the-scroll-saw/
Ask 10 scrollers and you will get 15 different answers. A lot of that is driven by the type of wood they use and the type of projects they like to work on. Personally I prefer Pegas for 80% of the work I do. The other 20% I use various Flying Dutchman blades. I have tries Olson and was not impressed. I know others that will only use Olson. My suggestion to you or any one else is try different brands, different sizes and different style teeth to see what works best for you.
I do not put tape or shelving paper on plywood. I glue the pattern directly to the wood with spray adhesive and remove it with mineral spirits. I have tried all the different tapes and shelving paper and all will lift off wood fibers. Some worse than others.
Nice score. If you are just going to use it to just cut down stock almost any blade will do. If you seriously plan do a lot of finish work like cutting molding or making miters for picture frames you really need a blade made specifically for a sliding miter saw. It has to do with the angle of the teeth. You also want a blade with more vs less teeth to get a nice clean edge. Pay the extra and get a carbide or at least carbide tipped blade. I have this blade on mine and I really like it.
https://www.woodworkingshop.com/product/ka12106/
Congrats on the new toy tool. Just a word of warning, voice of experience. When using a product like Johnson's Paste Wax make sure to buff off all the excess wax or some will transfer to the wood and "will" mess with whatever wood finish you might apply. Been there.
Sorry for your issues. Can you post a picture of the project and let us know what blade and type as well as what wood and thickness so we can better advise you.
I think I got me EX-21 in early 2017. Like January. On the motor there is a tag/label that should say where made and a serial. Mine was made in Taiwan. Also on the unit itself there is a tag/label that says: General International. The first batch of clones did not say General International.
Woodwiser just understand that any Dewalt Type 1 is over 20 years old. If you are not mechanically inclined or have a friend/relative who is, it might not be the way to go.
While I have not made any of these boxes I have made numerous Sue Mey projects and I find her instructions pretty complete and straight forward. Were there no instructions included? You might also consider contacting her via here website. https://www.scrollsawartist.com/contact-me....html
I seldom cut only a single piece of 1/8" (3mm) Baltic Birch but when I do I use a #1 or even a 2/0 reverse tooth blade. Unlike many others I slow the saw speed down again only when cutting a single piece.
Don't fret (pun intended) about the back.
Nice job Carl. Scrolling does take practice. You develop a feel. Just keep at. Don't be afraid to experiment (woods, blade sizes, blade types, different type projects,...... ).
BTW I would probably have used a #3 blade.
Ike got the new Chinese made Excalibur. They are being sold under the General International label. Makes no sense to me. General International marketed the old Excalibur saws that were made in Taiwan. Why they stopped production and then brought them back after a couple years is beyond my understanding.