Dunlap 27

[Jeff Torgalski]

This message is directed towards anyone who has built a Dunlap 27, or Jerry Dunlap himself...

I'm building a Dunlap 27, and I'm confused about the building fixture. The frame 1 brace: what are it's dimensions supposed to be?

The bill of material says 1/2" or 3/4" ply, then the drawing says "Frame 1 brace 1/2" x 3/4" ply.

Should I have just started with 1/2" ply to build this? Also, if it's supposed to be 1/2" wide, the drawing looks very disproportional.

My guess is that when you lay the 30" piece flat, when you are viewing from the side, this piece is 1/2" wide, and stands 3/4" tall. Yes or No?

 

[MikeP]

Jeff,

I still have my building jig, I will go check it when I get home from work. I can't answer your question without looking at it.

-MikeP

 

[MikeP]

Jeff,

I have mine here in front of me. My frame 1 is 1/2 " tall 3/4" wide. After seeing how it all is used I don't see that it matters. It needs to be square in all directions, that's what really counts. Here are some Pictures.

www.ad.kengarff.com/mikep/cf90/jig1.jpg

www.ad.kengarff.com/mikep/cf90/jig2.jpg

www.ad.kengarff.com/mikep/cf90/jig3.jpg

-MikeP

 

[Jeff Torgalski]

Fix your fixture!

Jerry Dunlap, the MAN himself just emailed me with the correct numbers.....he wrote:

Jeff,

The photo of the Building Fixture shows the pieces to position the frames in black. The back piece is 1/2" wide and 3/4" high.

Now I hope somebody will FIX THOSE PLANS! so the people who aren't as internet savvy as us will know.

P.S. If anyone has a Dunlap 27, let us know what kind of motor and servos you have or setup tips, etc. Of course, we won't get the notoriety of the Villian S1's "owner's forum", but we can compromise with this thread, y'know?

 

[Jerry Dunlap]

Jeff,

I have run D27s with K&B 3.5ss, O.S. Max 21, and Thunder Tiger. About three years ago, I won the Spangler Memorial back in Illinois with a D27 and piped O.S. Max 21. I also tried running a piped Rossi on one and it didn't seem to like the extra hp. The motor that worked best on the boat was a K&B 3.5ss. Actually, it ran pretty well with that piped O.S . I didn't spend much time attempting to trim the boat for the Rossi. I just prefer to run a larger boat in 3.5 Mod.

The c/l of the prop is 1/4" - 5/16" above the bottom of the sponsons. I've added lead, at least 4 or 5 ounces to the sponson tips of all my D27s.

For steering, I would recommend a servo with at least 75 oz. in of torque. The last D27 I raced in 2001 had a third servo for mixture control.

JD

 

[Jeff Torgalski]

Does anyone have suggestions on the best way to cut 1/16" and 1/32" plywood? I cut a few pieces yesterday and I think I basically wasted ten bucks worth of wood. So far, I have a brand new Sears Craftsman scroll saw that I use, but I heard some people get really good results by scoring the wood with a razor blade over and over.(sorry, I don't and probably will never have access to a laser to cut parts like in my villain kit)

What do the pros do?

 

[Jerry Dunlap]

Jeff,

I cut the 3/32" plywood for the frames with my Dremel jig saw. The 1/16" and 1/32" ply can be cut with a Stanley cutter. I suppose there's a degree of skill that develops over time when using a jig saw.

It does take some amount of time to cut all the parts. That's one reason I build using wood over foam(WOF) - much fewer frames to cut.

JD

 

[Propjockey]

I've had excellent results this way. Score the cut line with an X-acto (or any razor cutter), and then tape over it with heavy duty, clear tape (I use 2" packaging tape). The heavier and stickier the better. Scotch tape don't work. Rub the tape down with the top of your fingernail at the cut line-make sure it's stuck really good. Then use your scroll saw and a very fine blade. Start with the edge away from the cut and peel the tape off TOWARD the cut--you'll be surprized.

 

[Jeff Torgalski]

Prop jockey,

I'm not sure I'm seeing this right.

So what you mean is I'm using the tape as a guide to make it difficult for the blade to cross over the scored line?

Correct?

 

[29tunnel]

Jeff,

This year I built 3 JD WOF's All 3 were cut out with a 9" band saw using a 1/8" blade. The thin 1/32" can be cut with a utility knife.,or the band saw. The band saw is also good for cutting foam. I used 6 min epoxy but be sure everything fits right before you glue, you won't have time to make adj.

 

[Propjockey]

Nope, you'll be cutting right down the middle of the tape. The tape keeps the wood from splintering.

 

[topfuel443]

I use a scroll saw?????

 

[TomMoorehouse]

ive don quite a bit of this stuff..... here are some tips/ideas:

1/32 ply.... get a good pair of scissors! just don't cut with the scissors all the way to the end or it will split.

1/16 ply... use the scroll saw.... it takes practice. better to cut too big and then sand to perfection.

1/8 and bigger (you could do this for all thicknesses) I use my router table with a laminate cutting bit.... use some scrap wood... at lease 1/4" thick.... preferably not plywood as it can have voids in the layers that will cause problems. I use 1/2" pine. use your jig saw to cut the part out in the pine first... cut a little big and sand to shape... then use double face tape to hold your plywood the the pine "jig" you just made and with the laminate cutting bit go around your jig. makes perfect parts with the ability to repete when necessary.... nice clean edges as well!

 

[hg-md]

It is my first scratch construction r/c boat that I am working on currently, but I have found a pocket planer to work well for shaping parts to size and fine tuning parts. its only about 4" long and about 1" wide.

 

[MikeP]

I like to cut with a dremel scroll saw a little big. Sand to fit with 80 grit on a sanding block.

I use carbon paper under the plans and trace the patterns onto the wood, use a straight edge on the straight lines. Works really well on the bulkhead frames with all the notches.

-MikeP