Hye Flyer

So today was a good day off from ‘real work’. I finally completed the CNC router build that I started in January of 2021. As many know by now, I tend to jump around projects just a tad. LOL.

so upon completion of that build, i wasted no time in applying its very existence to our love of Control Line airplanes of the past. After zeroing all three axis’s origin points, I loaded up no less than the CG Shoestring fuselage cad file. I had a single 1/2” x 4” sheet of balsa to use on this maiden test run. And of course it turned out to be just about 3/16 too narrow to do a complete cut (and of course not taking the time to learn how to use the machine I made an error in the initial positioning) but I ran the job anyway. Turns out I need to add a bit of balsa to the top front of the fuse and then the canopy will fit. The rest came out just fine. The job took 42 minutes to cut but I think once I learn more of what i am doing i can cut that down by a considerable amount.

AJ Sun

Hey Hye Flyer I would be one that would buy your kit. Never built a Shoestring but bought a $20.00 tracing kit but was not very impressed. I will PM you for detailsAJ

Hye Flyer

So I just ordered a modest supply of 1/2” balsa from National Balsa so it will be a bit of time before I put these short kits together but I have decided to cut the fuselage in one piece. Seems they only had pieces to glue together just to save them money… i figure I’d do the gluing and using the router and 45 seconds to cut an entire fuselage saving time and money for the builders.

AJ Sun

Okay Hye please keep me informed. Best of the holidays. AJ

Hye Flyer

Hi AJ, got an update... I just started cutting the actual balsa parts. waiting on new part for cnc router to cut the one-piece fuselage.

Hye Flyer

To keep the cost down on the 1/2” balsa for the fuselage, I glued two 1/2” x 3” x 24” sheets on edge and then added a bit on the end as the fuse is roughly 25” long. I think i need to tweak it just a bit but all in all, pretty close to original albeit one piece fuse. I am seriously considering using two 1/4” sheets as gluing them flat insures straight and its a bit stronger than a solid 1/2” sheet.

this puts my cost of balsa at 14.00 rather than 29.00 for single 1/2 x 6 x 36 with a lot of waste.

here is the fuse after cnc routing the sheet.

AJ Sun

Well ya Hye a lamination is a lot stronger. Your saying the machine is not long enough to cut a full fuselage. I think I understand. When you get this all figured out, build, cost,shipping to 76049, let me know. AJ

Hye Flyer

AJ, I can cut the full length of the fuselage… the 1/2 I ordered was 3x24”, just shy of the length needed, hence the additional stick on the back end. All glued up then routed. Probably enough 1/2 material to make a dozen 1/2” fuselages. In the future I will probably cut 1/4” full and let the builder laminate them together to insure they are straight and stronger.

Might have the complete short kit (just all original unique parts) ready by end of week. I’ll post an alert.
Pete

AJ Sun

Hye Pete I've been trying to communicate on the message side, but I don't think your getting it. I put funds in the mail at the address you had when I got the postal template. I want your Shoe String stunter. That kit we have been talking about. Sorry about the confusion. Use the address off the funds to ship it. I will let you know how it goes. I had planned on the flying Fool. For my next project but,I will build the shoe string after I finish the winter project. It's about done and ready to cover after I do the pre balance. Planning on Silk and dope finish.AJ

Hye Flyer

looked and don’t have any new messages. Look at your messages and my contact info will be there

mike in SC

Hye Flyer Very nice work: what's the diameter and RPM of your cutter? That makes a super clean looking cut.
Originally leading edge had a groove cut on the back of it to center on the ribs, what are your thoughts on those? Plus looks like these should be about 3/4" leading edge?

thanks for your efforts, these parts look great!
I built and flew one of these around mid-70s
Still have the fox 36x I used on it!

Hye Flyer

hi mike.. so I use 1/8 bit with a makita router as my spindle on full speed. I am surprised it was so clean without having to mess with it. LOL

so based on measurements, the front of the oringal ribs were near 1”.. so i am thinking a 3/4 symmetrical LE with 1/16” backer at 1” then another spaced apart to accommodate the ribs… then its just a matter of punching a small notch in the 1/16” backer to accept the little notch on the front of the rib.

i haven’t built mine yet but have done a bit of work on the LE… will post pics when I get home

mike in SC

Hye Flyer : First your setup is excellent: the diameter of that Makita must be maybe 4"-5"? Then use MDF or some sacrificial board under balsa? Thats a pretty big work surface too, maybe 4'x4'?
What file type to drive the x-y? .dwg? Sorry just curious about the operation. Before I retired, we had a "Crossbow" programmable X-Y table that held a plasma cutter, and we could cut out just about any shape in steel up to 1/2"!
Second: I like the 1/16 attached to 3/4 symmetrical LE... I can't really see anywhere in the Goldberg drawings what the flat front of those ribs measured , but using those plates between ribs will add rigidity!

Hye Flyer

if you look up V1 engineering and look for the MPCNC Primo, that is what I built. I built it bigger than their recommended size and have had no problems to date. Yes, mdf spoil board. I have not ventured into a plasma cnc yet… but I think that might be my next build LOL

AJ Sun

Hi Pete well I think it's my server, on the message side old I pad, but I understand or maybe not. I get funds all the time under my shop name and can deposit. But I will comply with what you suggested. Please void that check and place it in my shipment. New funds are in the system. And let me know when it arrives I am getting your messages I think,but still can not answer. AJ

Hye Flyer

Still making shoestrings