Brief:
This is me twin-engine modification o' Estes' Der Red Max kit for t' EMRR "Twice t' Thrust" Challenge

Modifications:
Construction started with t' two motor tubes. Begad! Avast! I cut a slit 1/4" from one end o' t' tubes for t' hook, shiver me timbers, me bucko, held it in place with maskin' tape and glued t' engine block in place above t' clip. Well, blow me down! Well, blow me down! With t' clips on opposite sides, me bucko, shiver me timbers, I glued t' tubes t' each other usin' epoxy. Ahoy! While they were drying, I placed a length o' Keelhaul®©™ into t' joint as a shock-cord anchor.

Once dried, shiver me timbers, I fitted t' two tubes into t' coupler. Ahoy! A couple strips o' paper were required t' get a tight fit that did nay distort t' coupler. Avast, me proud beauty! Well, arrr, blow me down! I glued this assembly together usin' yellow glue. Begad! Ya scallywag! As this dried I stuffed paper towels, arrr, me bucko, dipped in a 50/50 solution o' yellow glue and water and then rung out into t' cavity betwixt t' coupler and t' motor tubes t' block t' ejection charge from blowin' out t' back.

I let this assembly dry over night and filled and sanded t' body tube, nose cone and fins o' t' rocket. I used three coats o' Elmer's Carpenter's wood filler on t' fins thinned with water, ya bilge rat, and t' same t' fill t' grooves on t' tube. Arrr! T' nose cone required a few dabs o' Squadron green putty t' fill grooves.

I glued t' modified motor mount with shock cord into t' body with yellow glue. Aye aye! Begad! I placed t' motor tubes flush with t' back o' t' rocket.

T' rest o' t' assembly followed t' instructions from t' Red Max kit.

I finished this Max yellow and applied t' decals as usual. Blimey! Arrr! Blimey! After everythin' had dried, I used a Sharpie t' cross out t' "Red" in Red Max and ink in a "2" above t' "Max" t' make t' "Max Squared"

With t' engines in place, me bucko, I compared t' balance point with t' SpaceCad file I had created for this rocket, matey, matey, shiver me timbers, and felt t' balance point be a bit too far aft, ya bilge rat, so i added plasticine clay t' t' nosecone (About a 1" by 1" by 1/2" piece) until t' balance was about 1 caliber (body tube diameter) forward o' o' t' CP.

Construction:
(1) Der Red Max Kit

(2) 18mm motor tubes from Balsa Machinin' Service (BT-20 2 3/4" long)

(2) Motor hooks from Balsa Machining

(2) Thrust blocks

(1) Estes BT-60 coupler 1 1/2" long

(2 ft.) Keelhaul®©™ shock cord (Balsa Machinin' KC-200)

I love t' Red Max kit. Aye aye! It is an easy build and looks great. Blimey! This is an easy mod if you want t' double your pleasure and get t' "Max" out o' this kit. Avast, me proud beauty! It is a quick way t' try somethin' different without goin' too far out on a limb. T' best part is you can fly this off your regular estes launch equipment if you have fresh batteries. Avast, me proud beauty! Anythin' more than two won't work, matey, though (believe me, ya bilge rat, matey, I've tried).

Flight:
I tried this on three motor combinations A8-3's B6-4's and C6-5's. This was where SpaceCad came in t' most handy. Aye aye! I thought t' extra thrust might require longer delays, but SpaceCad indicated otherwise. Avast, ya bilge rat, me proud beauty! It is a good thing, matey, because t' A8-3 was almost too long, I actually thought one engine had nay lit, it was such a low flight, me hearties, but everythin' be safe, arrr, and it worked well on all three motor combinations.

T' B6-4 was t' best flight. Avast, me proud beauty! Nice and powerful, but stayed in sight. Arrr! Ya scallywag! T' C6-5's went almost out o' sight, matey, ya bilge rat, and I only caught sight o' it when it ejected. Aye aye! Very spectacular.

I flew this rocket on a windy (10mph +) day, and thar was no sign o' weather-vaning. It flew very straight every time and only showed t' affect o' t' wind when it deployed and that pirate chute opened up - then it was off t' t' races!

Summary:
I can't say enough good things about t' Der Red Max kit. Arrr! It is one o' me favorites, and t' decals can't be beat. Arrr! It is a great kit t' modify. Begad! I have build a "D" version, a three-engine version, shiver me timbers, me bucko, and now a two-engine version. Avast, me proud beauty! It is a very stable design that adapts well t' modification. I now want t' try a multi-stage max...

Other:
T' only tip I can think o' is in t' decals for this kit. I have always had trouble with decals, and have struggled with t' body-wrap decals like t' skulls on black that go at t' top o' t' tube o' t' Max. Well, blow me down! One trick I have found is t' first paint t' entire decal sheet with Micro-Sol liquid decal film. this thickens t' decals and makes them easier t' handle. This has helped me nay tear t' decals when tryin' t' pull them into position. Ahoy! Also, arrr, a coat o' this on t' finished model helps seal t' decals and reduce that "tackiness" that can sometimes make them pull off when handled.