Using the Cricut maker for cutting balsa plane parts. (long)

[Mark Mc]

For Christmas I got a Cricut Maker machine for my wife. My wife does quilting, so I figured that it would be great for her.  It just so happens, quite coincidentally mind you, that the Maker can cut 1/16” and 3/32” balsa.  That had nothing, nothing to do with why I bought the Maker…..

I figured this would be great for building my models, so I went to Outerzone and downloaded the plans for the Skybolt 1/2A CL plane and started experimenting with converting the .pdf to the .svg file needed for the Maker.  My initial trials were unsuccessful, so I switched over to using Inkscape (a free program, equivalent to Corel Draw) and started tracing the plans.





Then I sent the .svg files from Inkscape to my Cricut machine and cut the ribs and the upper and lower fuse sheeting from 1/16” balsa.










I had to do some more learning, but then finished up by cutting out the fuselage sides and formers.






As you can see, the ribs are pretty nigh perfect.  I'd never be able to do them that clean with an X-Acto knife and a sander.  Man! I wish I’d had this thing four years ago when I cut out three sets of Skyray 35 ribs individually by hand.

[Mark Mc]

At the local clubhouse, a fellow club member stated that he had a Cricut Air2 that he was looking at using it for modeling.  So I showed him pictures of what I had done.  Since I knew he was into FF models, when I went home that afternoon I decided to see what I could do with a rubber FF plan.  I downloaded a .pdf of a Veron Champ and went to work. 





About four hours of work gave me this:





About another hour and I had this:





I brought it to the club meeting a couple of days later for show-and-tell.  Then, since I’m not much of a FF builder, I went ahead and gave him the parts sheets and plans to build at his leisure.

I was also posting this on RCG, and some guys had questions about what I was doing, so I made up a couple of videos to show how I did the Champ parts.  I have since learned a few new tricks, and I’m going to post another video soon with lessons learned.



Part 1 is here: 





Part 2 is here: 

[Mark Mc]

But, the Skybolt 1/2A CL that I started on wasn’t doing it for me, so I also downloaded the plans for the 1/2A Red Wing, from the December ‘64 Flying Models and I did up a set of files to cut the ribs.  The ribs vary in size from 5.25 inches to 14 inches long.









You can see that the rib pairs are perfectly matched without a lick of sanding.  I couldn’t do that by hand without a lot of slow and careful sanding.






Then I tried to make some jig ribs.  The ribs in my .svg file are dashed along the rib outline, as you can see above.  That way, I can just pop out the L.E., T.E., and spar cutouts and slide the sticks through the holes to jig up the wing while I build.  Then, once the wing is complete, I can just cut along the dashed line and the wing is free and in perfect alignment.  But, even though my .svg file has dashed lines around the rib outlines, the Cricut machine cut them as solid lines:





No biggie.  I’ll just tape the ribs in place in the jig.  That should hold them while I build the wing, and then I can just peel away the tape when I’m done.  I’ll have to do some more experimentation to get the dashed lines to cut like I want instead of the solid lines.







Mark

[Dennis Adamisin]

EXCELLENT! 

I was not aware that you could do anything except Cricut files on a Cricut machine, main reason I've ignored it.  Gonna have to give it another look. THANKS

[Fred Cronenwett]

I just bought a Cricut maker 3 myself, but with full intention of using it for vinyl decals, paint masks and cutting balsa parts.

I have cut the decals (which can become a paint mask) and I also use inkscape, great program

This is the video I posted on how to trace a former shape, I just haven't cut the balsa part yet

Thanks for adding this as a topic!

Fred

[Dave Harmon]

At a club meeting I had those ribs and other parts in my hands that Mark cut using the machine.
I was stunned at the precision of the cut....just incredible!
Thanks Mark for showing us what can be done!!

[frank williams]

Absolutely Incredible ..... Yes thank goodness for the little ole lady scrapbookers .... but I have a Silhouette machine ..... I'll have to see if they have something similar for the geared head cutter

[Fred Cronenwett]

What I like is that you can cut your own custom vinyl decals, paint masks - I am not sure all machines can cut balsa, the Maker 3 will cut balsa

[Mark Mc]

Fred,

Thanks for the video.  It made me go back and do some playing around with the Inkscape program.  I don't paint, so I won't be making masks, but I might do some vinyl graphics.  Also, I need to do more playing around with layers/colors.  I want to figure out how to do Stars and Bars and the like with this.

What I really was looking for is information on cutting Monokote with the Cricut machine.  I've seen references to it, but not many specifics.  I have a couple of projects awaiting finish trim with Monokote to be ready to go, once I get them out of storage.  Anyone have experience with cutting Monokote that wants to chip in?

Mark

[Mark Mc]

Hmmm...  I wonder if I'm ambitious enough to make this an article for Model Aviation?  Unless you were planning on doing that, Fred?

[kevin king]

Make the article Mark. I use the Brother Scan n Cut 2 but have only made paint masks. This is a topic that needs more exploration.

[Fred Cronenwett]

It's worth writing the article, everytime I look thru a Cricut facebook page it has lots of great projects that people are working that are all totally different when compared to model airplane projects.

I haven't considered looking into how to cut monokote since I don't use a lot of that. I wonder if you put monokote on the purple mat so that it doesn't move and see if that works using the std sharp point. maybe tape all of the edges so that it does not lift up and move.

Fred

[Fred Cronenwett]

Mark - I do have a topic in the May 2022 CL scale column with the Cricut but it only covers a small portion of what is possible. The topic really needs a full article

Fred

[pmackenzie]

I have a 22" x 43" CNC router, works really well for F2B sized ribs, and thicker parts.
But this looks like a great idea for smaller ribs, like in FF models.
Add in the ability to do Vinyl trim and masks, and other things like that, and it is hard not to buy one

[pmackenzie]

Which model are we talking about?  I went on Amazon and there must be at least 10 of them, all sized and shapes.

Ken

From what I was able to find, Cricut Maker or Maker3 are the ones that will do balsa.
3 can do really long rolled media, and is faster than the Maker for some jobs.
For doing balsa, I think the maker will do just as well as the Maker 3.
You will also need the cutter head and the cutting mats.

https://www.imore.com/cricut-maker-vs-cricut-maker-3

[Fred Cronenwett]

The Cricut Maker 3 that I have I bought for myself to use for the model airplanes: Balsa, vinyl decals and masks!

[Peter in Fairfax, VA]

Is there any special method to make sure the radius of the cuts in the ribs for the 1/4" square spars are square cuts, not rounded?

[Mark Mc]

Is there any special method to make sure the radius of the cuts in the ribs for the 1/4" square spars are square cuts, not rounded?

That's the great thing about the geared cutting blade, the cuts are started and stopped at each point of the square.  Just like if you were cutting the ribs for square spars by hand with an X-Acto knife.   If the .svg file has square 90 degree cuts, you get square 90 degree cuts.  See the third and sixth photos of the first post to see how sharp the cuts are.

Mark

[Peter in Fairfax, VA]

Thanks for mentioning the geared cutting head suitable for the Cricut Maker or Cricut Maker 3.  Precisely what is the geared cutting head, technically?  Is this an item which is included in the box with the standard offering, or something purchased later?

Also, are you doing single pass, or multiple passes until the mat itself is getting cut?  Ever get stuck blade scenarios?

thanks, there is some enthusiasm from some fellow club members.

Peter

[Mark Mc]

The Maker and Maker3 have a geared drive for a couple of different types of knife blade.  The knife we use for balsa is just like the tip of a #11 blade.  As the head moves around the wood, the gear keeps the sharp angle of the blade facing into the cut so that it is a clean cut.  This type of blade is not included with the Maker, you have to buy it separately.  I do not know about the Maker3.  I do not see that you can get a stuck blade scenario.  I have read that on the replacement blades, several people have complained about the blade snapping.  I have already dulled one blade and bought a replacement blade.  Cricut would like you to buy the whole blade assembly for $23 (on Amazon) to $33 (at the local Hobby Lobby), but you can also buy the individual blade for $12.00 on Amazon.  I have already dulled one blade and replaced it with a second assembly, since I figured it'd be good to have two drive housings for quick swaps.  I have looked online to see if anyone has good instructions for sharpening a dull knife blade, but I haven't found anything about sharpening them.  Everyone just seems to replace them.  I have an idea on how I want to sharpen my dull blade, but haven't had time to give it a go.





When starting the cut, you specify what material you are going to cut and the software determines how many passes it will take.  1/16" balsa is set for four passes.  Once those four are done, the program prompts you to check to see if the cut went all the way through.  If the cuts are complete, you press the load/unload button to eject the mat.  If the cut isn't complete, you hit the "start" button again and it will do one more pass.  You can keep pushing the start button as many times as needed to cut completely through the material.  When I was using contest grade 1/16" balsa for the FF model parts, I hit the pause button on the Maker after three passes and checked to see if the parts were cut all the way through.  They were, so I just hit the unload button and finished the cut early.

Mark

[Mark Mc]

Oh, I was asked if I could cut 1/32" ply for another club member's project, so I tried it.  No good.  The lower lamination just separates, and the knife blade just pushes it into the mat without cutting the wood fibers, so it just messes up the mat.

[Bruce Shipp]

How small diameter hole do you think it would cut? Would it cut 1/4” or 5/16” diameter for wing night rod holes?

Thanks.

Bruce

[Mark Mc]

The smallest hole I've cut so far in 1/16" balsa is about 1/8" diameter.

[pmackenzie]

FWIW, my Cricut arrived today. (It was on sale online at Costco)

First impressions:
   Bigger than I thought it would be.
  "Heavy with goodness"
  Very nice and clean design, seems well made.

No chance to actually power it up yet, and still waiting for the knife blade. It comes with the regular blade, and the roller cutter.
Tomorrow I will get the software installed, and play around with the regular blade and some of the materials it came with.

I think/hope the blade will be delivered on Friday.

[Bruce Shipp]

For those of you with experience using the Cricut to cut balsa, what do you think is the thickest balsa that can be successfully cut?

[Mark Mc]

For those of you with experience using the Cricut to cut balsa, what do you think is the thickest balsa that can be successfully cut?

Cricut says 3/32".  Also, they say the thickes material you can use in a Maker is 2.4mm.  I just bought some 1/8" balsa to try when I get a chance.  If that doesn't work well, I was thinking of putting a 1/32" shim under the knife blade shoulder to raise the blade a bit.

Mark

[pmackenzie]

The issue will not be the knife.
The rubber feed rollers on each side are only ~2.5mm larger in radius than the cross bar, so that limits the material thickness.

[pmackenzie]

Played around a bit with mine, mainly trying to figure out a workflow to go from CAD to parts. A work in progress
I have to figure out two new-tome programs: Inkscape and Design Space.

-Importing DXF directly into Design Space did not seem to work, I had to go through inkscape.

-Importing DXFs into inkspace I had to scale up by 25.4, despite everything being set to inches.

-SVG import from Inkspace into Design Space totally messes up the scale. Google found a work-around :
  - select everything in Inkspace  (CTRL-A) and it will tell you the bounding box dimensions
  - then in Design Space do the same, and adjust the bounding box to match.

-Design Space is totally geared towards you buying images,fonts, etc from Cricut as a basis for your project, so it is online all the time.
 It insists on saving your work to the cloud, or locally and the cloud. No option for locally only.
 I tried going off-line (turned off WIFI connection), and you can continue to work and save locally, but I was unable to cut anything.
 A bunch of Javascript errors pop up when I tried. Supposedly you can cut while offline, so not sure what the problem is.

-Design Space won't run in XP, which is what is on my shop PC. But I figured that might be the case.

Just cutting paper tests for now , still waiting on the balsa-cutting blade holder.

[Mark Mc]

The issue will not be the knife.
The rubber feed rollers on each side are only ~2.5mm larger in radius than the cross bar, so that limits the material thickness.

Drat!  You are right.  I just took a piece of 1/8" and tried to get it to fit under the roller bar and it won't.  I had just assumed from other things I had read that it was a knife housing clearance issue.  Guess I'm back to laminating two 1/16" pieces together after they are cut.

Mark

[pmackenzie]

First cuts, some Magician .15 ribs that I already had drawn up.
Results are very nice. The reference rectangle was drawn 1" x 4", it measures 1.002" x 3.999". Close enough to perfect!
The 1/16" wide spar web slot has a half circle at the bottom, the program was clever enough to know that it could not try to cut around it, so it sort of "stabbed" its way around.

It took a while, but in the end the transition from Cad to Inkscape to Design Space is working well.

- Any continuous cut needs to be a LWpolyline. Mine were all old style polylines, they did not work at all. It would end up as a bunch of short segments and be cut that way.
  I lost a lot of time figuring this out, but was determined not to have to do my drawing, or even any editing, in Inkspace.
  There is an Autocad R14 command "convert" that can turn old style polylines into the newer LW ones. If you are using a newer CAD program (and you probably should be ), this might not be an issue.

- As Mark suggested in his video, add a reference object in your CAD file, like the 1" x 4" rectangle. 
When you get into Design space you can use it to scale everything precisely.   Design space totally messes up scaling, no idea why.

-I will make some sort of in-feed/out-feed support rails, so that the mat can't bend under its own weight as it goes back and forth. I worry that the flexing could allow the balsa to come "unstuck" from the mat.  Likely some lexan strips, or just bent 1/4" wire will work.

- Tablet Design space app does not include balsa as a material for some reason   The PC program does.

[Mark Mc]

-I will make some sort of in-feed/out-feed support rails, so that the mat can't bend under its own weight as it goes back and forth. I worry that the flexing could allow the balsa to come "unstuck" from the mat.  Likely some lexan strips, or just bent 1/4" wire will work.

I keep saying I'm going to do that also.  But I just took an empty cardboard box of the right height (just below the level of the slot) and put it at the back, and a couple of binders and put them in front fold down panel of the Maker.  Works good enough for me for right now.

Your ribs look good.  I'm having a ball making ribs.  I just need to stop cutting and start gluing.

Mark

[john e. holliday]

Will you guys be able to cut ribs for somebody?

[Dwayne Donnelly]

Will you guys be able to cut ribs for somebody?

That's a very good question Pat, my new best friend. 

[Mark Mc]

Will you guys be able to cut ribs for somebody?

Tricky question.  No problem for a local club member as I could work with them real time.  Local balsa is expensive and quality is not what I'd wish on anyone else.  Plus, making sure what I was going to cut is what one desired is difficult if I couldn't be provided real time feedback.

Mark

[Bruce Shipp]

Do you see a difference in part quality between contest grade balsa and heavier wood?  Can the balsa be too soft/light?

[Mark Mc]

I haven't seen a difference in the quality of the cut.  Whether contest grade or the average stuff I'm seeing at the hobby shop, the cut is cleanly defined.  It just takes more cuts for the harder stuff.  I suppose that if the knife blade is well used and really dull, it could tear the balsa.

[Brent Williams]

Can it do similarly thin basswood? 
What about 1/32 plywood?

[pmackenzie]

Can it do similarly thin basswood? 
What about 1/32 plywood?

Basswood, yes. Cricut actually sells sheets of it for doing 3D puzzles and similar projects

https://www.amazon.com/Cricut-Basswood/s?k=Cricut+Basswood

Mark mentioned earlier trying 1/32 ply, and did not get it to work.

[Mark Mc]

I tried doing a cut on 1/16" basswood for a club member.  If you're going to do detail work on basswood, you'll probably be disappointed.  If you're just cutting simple shapes, it should be okay.  When I tried doing some grills from 1/16" basswood, the basswood was too brittle and broke between the grill bars.

[Fred Cronenwett]

I cut a fuselage former tonight with good results using medium density balsa. You do have to pay attention to the overall size of the part when you get into design space. I started with a PDF, traced the scan and got a good SVG file but when I got into design space I didn't notice that the part got enlarged somehow. I used the 1 x 1 square trick that Mark mentioned in his video.

[Mark Mc]

I’m just starting experimenting with Monokote.  I was going to start experimenting by making some roundels and Stars and Bars, but I found I have no white or red Monokote.  So I just found a generic image to use for playing.  A tiger graphic.

I tried using the blue mat, which is the less sticky mat, first.  But it’s still too sticky to be of much good.  All experiments were a fail with Monokote.  I’m trying a different approach with the blue, but it’ll have to wait ‘till tomorrow.

I pulled out the pink mat, which is the fabric mat.  It is the least sticky mat they have.  I just separated some black Monokote from the backing and stuck it to mat.  I made a custom selection for Monokote in the Design Space using a fine cutting blade on the lowest pressure, one pass only.  Then when it went to cut, I lowered pressure even more.







Instead of the normal transfer film that Cricut sells, I placed a sheet of Glad Press N’ Seal over the Monokote and carefully peeled off the Monokote from the mat, using an X-Acto knife tip to help it come up.







Looks good.  I had a slab wing plane next to the work table, so I figured I’d use that to see how well it transfers.  I spritzed the wing with Windex and placed graphic on the wing, squeegeeing the Windex out as I went like I normally do when doing the Press N’ Seal method. 






I’ll let it set overnight and then finish it tomorrow morning.

[Mark Mc]

So it looks pretty good after removing the Press N” Seal.  I really need to get something to polish Monokote, but I don’t feel like paying the price for the official Monokote polish.




So I went back to my experiment with the blue mat again.  Last night I took a sheet of Dollar Tree vinyl and put it on the blue mat.  Then I cut a strip of black Monokote 3” x 12”.  I spritzed the mat with Windex and put the Monokote on, squeegeeing it as I went.  It sat overnight to let the Monokote stick to the vinyl, and then I fed it into the Maker.  I tried the tiger graphic again, as well as some generic shapes.  As you can see, the detailed image didn’t work out so well, but the generic shapes came out just fine.  I think this will work out great for most of the things I’ll use the Cricut for, and do the fabric mat thing for detail work.








Mark

[Dwayne Donnelly]

I’m just starting experimenting with Monokote.  I was going to start experimenting by making some roundels and Stars and Bars, but I found I have no white or red Monokote.  So I just found a generic image to use for playing.  A tiger graphic.

I tried using the blue mat, which is the less sticky mat, first.  But it’s still too sticky to be of much good.  All experiments were a fail with Monokote.  I’m trying a different approach with the blue, but it’ll have to wait ‘till tomorrow.

I pulled out the pink mat, which is the fabric mat.  It is the least sticky mat they have.  I just separated some black Monokote from the backing and stuck it to mat.  I made a custom selection for Monokote in the Design Space using a fine cutting blade on the lowest pressure, one pass only.  Then when it went to cut, I lowered pressure even more.







Instead of the normal transfer film that Cricut sells, I placed a sheet of Glad Press N’ Seal over the Monokote and carefully peeled off the Monokote from the mat, using an X-Acto knife tip to help it come up.







Looks good.  I had a slab wing plane next to the work table, so I figured I’d use that to see how well it transfers.  I spritzed the wing with Windex and placed graphic on the wing, squeegeeing the Windex out as I went like I normally do when doing the Press N’ Seal method. 






I’ll let it set overnight and then finish it tomorrow morning.

Hi Mark, please a question about the press and seal, I did this for the first time recently and the press and seal left residue behind after I peeled it off, did you use the  iron before removing  it or after?
Thanks

[Mark Mc]

Dwayne.  After heating the Press N' Seal with a heat gun to remove it, it does leave the residue.  I iron it down first, then clean off the residue.