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View Full Version : Intersection of TR3 D7 D9


TheArf
25th September 2010, 03:47 PM
I think I know the answer already but how important is it for this intersection to line up as per the book. I have been on this all morning but I cant get them to line up. I have taken them apart three times, checked all of the cut angles with combination set protractor, and all check out correct. I have marked out the 491.5 line on BR5 & BR6 so that D7 & D8 are pitched together. For some reason I cant get D7 to be in the right place and keep the 151 mm overhang at the very back. Bet when I go back tomorrow with fresh eyes it will jump out at me Grrrrrrrrrr

Talonmotorsport
25th September 2010, 06:48 PM
Ah this bugged me for ages when I built my first one. Have you welded the double SB1's to BR12 and SB2 yet or just tacked them? The trick to getting SB1 SB2 and all the top rails in place is to start at the front.
1. Tack the front frame in place making sure it leans back the required 75mm and is square with the base rails. Then tack 2 braces from BR8+9 in place to keep it there.
2. Tack SB1's to SB2 and D7+8 not forgetting they need an extra angle cutting on the 40' end!
3. Add U3-8 and all the Top Rails.
4. Now this is where making sure your build table is square and leveled up using a spirt level across it's width and length will make life alot easier in the next part. Run a tape across from the rear corner of SB2 to the opposite front corner of the front frame, then repeat. When these two measurements are within 1-3mm pat your self on the back as you've done very well indeed!
The spirt level will help you get SB1and SB2 square to the base rails or square left to right, if in dought get a step ladder to look at it from the top to give you an idea of where your going wrong.

TheArf
25th September 2010, 07:15 PM
Everything is just tacked into place so far. The front frame is in place with the 75mm lean towards the back. I have then tacked in the SB1 & SB2 into place with the top rail linking the two sides. From the front rail working back I have tacked in all the uprights from front to rear and also TR1,TR2,TR5,TR6,TR7,TR8 & TR9. All of which are just tacked in and so far everything has lined up well, it's just frustrating not to be able to see the wood for the trees, might have to get some beer goggles on tonight then my head might work properly tomorrow.

leroybrown911
25th September 2010, 08:56 PM
Not sure if this helps your issue, but with ref to the 151mm overhang. I hadnt spooted this dimension in the book so calculated it myself. When I did realise the dimension was in the book I had calculated it to be different for some reason. not sure if I have cocked up here as not in the amendments but I make the overhang 154.5mm. Calcs I used are:

sin17 x 528=154.5mm (or as near as damn it)

Anyway 3.5mm isnt the end of the world, I dont think?!?

Cheers

Talonmotorsport
25th September 2010, 09:49 PM
Oh yeah and did I mention you can cut 2-3mm off TR1+2 to make things fit, auto CAD is good for doing drawings but the average car builder can only cut to 0.5-1mm accurately. A little over here and there and it soon adds up.

TheArf
26th September 2010, 07:20 AM
Thanks guys, get a fresh outlook on the problem later today, got to go out with swmbo as she collected her new car yesterday so we are going for a spin, got to allocate some quality time with her this morning